Automatic regulation and regulators. Automatic engine speed regulators

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Ministry of Education and Science of the Republic of Kazakhstan

East Kazakhstan State

Technical University. D. Serikbaeva

Department "Industrial Energy"

abstract

Subject: " Automatic regulators»

Ust-Kamenogorsk 2008

Select the regulatory channel

Main indicators of regulation quality

Typical block diagram of the regulator

Classification of regulators

Positional regulators

Integral regulators

Proportional regulators

Proportional and integral regulators

Differential regulators

Choosing a type of regulator

Formular method for determining the settings of the regulator

Calculation of settings on the frequency characteristics of the object

Experimental adjustment methods

Method of unsuccessful oscillations

Method of fading oscillations

Regulation with noise

Methods for setting up two-joil control systems

Autonomous setting method for regulators

The iterative setting method of regulators

Method of analytical design of regulators

The main task of regulatory systems is to stabilize the parameters of the process at a given level when exposed to external perturbing effects acting on the control object. This is done by automatic stabilization systems. Another equally important task is the task of providing a program transition to new modes of operation. The solution to this problem is carried out using the same stabilization system, the task of which changes from the software master. Controller Automatic Design Analytical

The structural scheme of the single-circuit system AP control is shown in Fig. 1. The main elements of it are: ar - automatic regulator, mind - power amplifier, it is an actuator, RO - adjustable organ, SO - actually an object of control, D - sensor, NP - normalizing converter, health Master, ES - Comparison Element.

Variables: Yz - a Signal Signal, E - Control Error, Up - Regulator Output, U Y - Control Voltage, H - Movement of the Control Organ, Q R - Consumption of Substance or Energy, F - Outrageous Impact, T is an adjustable parameter, Y OS - feedback signal (output voltage or transducer current).

The normalizing converter performs the following functions:

· Converts a non-standard sensor signal to a standard output signal;

· Signal filtering;

· Carries out the linearization of the static sensor characteristics in order to obtain a linear range.

For calculated purposes, the initial scheme is simplified to the scheme shown in Fig. 2, where the AR is a controller, the OU - the control object.

Select the regulatory channel

The same output object parameter can be controlled by different input channels.

When choosing the desired control channel, proceed from the following considerations:

· Of all possible regulatory effects, this flow of the substance or energy supplied to the object or the returned from it is selected, the minimum change of which causes the maximum change in the adjustable value, that is, the gain of the selected channel must be, if possible, maximum. Then, on this channel you can provide the most accurate regulation.

· The range of permissible change in the control signal must be sufficient to fully compensate for the maximum possible perturbations arising in this process, that is, a supply of control power in this channel should be provided.

· The selected channel must have favorable dynamic properties, that is, delay 0 and ratio 0 / T 0, where T 0 is the time constant of the object, should be as smaller. In addition, changing the static and dynamic parameters of the object via the selected channel when the load changes or in time should be insignificant.

Main indicators of regulation quality

Requirements are made to automatic regulatory systems not only on the stability of regulatory processes in the entire load range on the object, but also to ensure certain qualitative indicators of the automatic control process. They are:

· Control error (statistical or rms components).

· Regulation time.

· Operation.

· The oscillating indicator.

Dynamic regulation coefficient R D, which is determined from the formula

where the meaning of the values \u200b\u200by 0 and y 1 is clear from Fig.3.

The value of R D characterizes the degree of influence of the regulator on the process, that is, the degree of reducing the dynamic deviation in the system with the regulator and without it.

The magnitude of the overall depends on the view of the signal being processed. When working out stepped impact on the setting signal, the magnitude of the overall is determined by the formula

where the values \u200b\u200bof x m and x y are shown in Fig.4.

When working out the disturbing effect, the magnitude of the overall is determined from the ratio

where the values \u200b\u200bof x m and x y are shown in Fig. 5

Regulation time - This is the time for which the adjustable value in the transition process begins to differ from the steady value less than a predetermined value, whereby the control accuracy. The regulator settings are selected so as to provide either the minimum possible value of the total regulation time, or the minimum value of the first half-wave of the transition process.

In some systems, Art is observed an error that does not disappear even after a long time interval is static regulation error -- from.

Regulators with an integral component error in the steady state are theoretically equal to zero, but practically minor errors may exist due to the presence of insensitivity zones in the system elements.

The oscillatory indicator M. It characterizes the magnitude of the maximum module of the frequency transfer function of the closed system (at the frequency of the resonance) and, thus, characterizes the oscillatory properties of the system. The oscillativity indicator is clearly illustrated in the graph Fig. 6.

It is conditionally believed that the value M \u003d 1.5 ... 1.6 is optimal for industrial systems, since in this case it is provided in the range from 20 to 40%. With an increase in M, the vibration in the system increases.

In some cases, the bandwidth of the P system n is normal, which corresponds to the gain level in the closed system 0.05. The greater the bandwidth, the greater the speed of the closed system. However, this increases the sensitivity of the system to noise in the measurement channel and the dispersion of the control error increases.

When setting up the regulators, you can get a sufficiently large number of transient processes that meet the specified requirements. Thus, some uncertainty appears in choosing the specific values \u200b\u200bof the parameter settings of the regulator. In order to eliminate this uncertainty and facilitate the calculation of the settings, the concept of optimal typical regulation processes is introduced.

Mix three typical process:

1. Aperiodic process with minimal regulation time (Fig. 7). This typical process assumes that the indignation F (automatic stabilization system) is being implemented. In this case, the settings are selected so that the T P control time is minimal. This type of model process is widely used to configure systems that do not allow oscillations in a closed control system.

2. Process with 20 percent overstate and minimum first half-period time (Fig. 8). Such a process is used to configure most industrial SARs, as it connects to a sufficiently high speed (T1 \u003d MIN) with limited oscillativity (\u003d 20%).

3. A process that provides a minimum of an integral quality criterion (Fig. 9). The integral quality criterion is expressed by the formula

where E is the regulation error.

The advantages of this process include high speed (1st half-wave) with quite significant oscillatibility. In addition, the optimization of this criterion for the parameters of the adjustment setting can be performed analytically, numerically or by modeling (on AVM).

Typical block diagram of the regulator

The automatic regulator (Fig.10) consists of: a zoom-defining device, a comparing device, an amplifying-transform device, BN settings block.

The specifying device must produce a highly stable setting (regulator installation) or change it according to a specific program. A comparing device allows you to match the reference signal with a signal. feedback And thereby form the magnitude of the E P control error. The amplifies-transforming device consists of a block of formation of the control algorithm, the parameter settings block of this algorithm and power amplifier.

Classification Regulators

Automate the regulators are classified according to different features. For example:

· By type of adjustable parameter: Pressure regulators, flow, level, temperature, and so on;

· By the nature of the action: Intermittent regulators and not intermittent;

· According to the method of action: regulators of indirect and direct action.

These types of classification of regulators are not determining, since they do not characterize their properties. The main feature, according to which classifies and regulators, regardless of the belonging to one of the above groups, is the characteristic of the action, that is, the relationship between the change in the adjustable value and the movement of the regulatory body.

According to the characteristic, the regulators are divided into the following:

· Positional (PZ) regulators;

· Integral (and) regulators;

· Proportional (P) regulators;

· Proportional-integral (PI) regulators;

· Differential (D) regulators (proportional-differential (PD), proportional and integral-differential (PID) regulators).

The input value of the regulator is a signal, a proportional difference between the specified and current values \u200b\u200bof the controlled (adjustable) value; The output is the position of the regulatory body.

Positional regulators

Automatic regulators (AR), in which the regulator may occupy a limited number of certain provisions, are called positional. Positional (PZ) Regulators belong to the group of intermittent regulators. Two- or three-position regulators are most often used.

Two-proprietary regulators, depending on the sign of the deviation of the controlled value, the regulating body is either completely open or completely closed. In two-position regulators, in addition to the two extreme, the regulatory authority has another (average) position, which contributes to a smoother change in the controlled value and reduce the number of response of the regulatory body per unit of time.

Fig. 7.2 Schematic diagram (A) and static characteristics (b) PZ regulator:

a) 1 object; 2-10 pipes; 3-regulating valve; 4 core; 5th rod; 6-float; 7-lever contact; 8.9-mobile stops-contacts; 11-spring.

b) I-specified value; II-neutral zone; 1-6 points characteristics.

The principle of the PZ regulator is next. For example, in the control object - the tank 1 by pipe 2 is supplied by a liquid, and along the pipe 10 it is consumed by the consumer (Fig. 7.2a).

Sensitive element of the regulator - Float 6 measures the level in the tank; The current level value is determined by the position of the Stem 5 and the connected lever rigidly with it, which through the spring 11 is connected to the power supply voltage. U.. The specified values \u200b\u200bof the upper and lower levels are determined by the position of mobile stops - contacts 8 and 9 installed manually.

When lifting the level above the given contact 7, it will clone with contact 8 and the winding will turn out to be B. The traction electromagnet, so that the core 4 instantly moves upwards, lead to the closure of the regulating organ 3 (valve). When lowering the level below, a given contact should be closed with contact 9, the winding will be under voltage BUT traction electromagnet, anchor 4 moves down, which will lead to the opening of the regulatory body. The diagram is an example of two-position regulation.

Regulator equations:

m \u003d _-- nrand - dy\u003e --_--and-- m - \u003d 1 - Prand - D - Y

From the static characteristics of the two-position regulator (Fig.7.2, b) it can be seen that increasing the level in the tank corresponds to moving by points 1,2,3,4; Points 2 and 3 correspond to the instantaneous movement of the regulatory body from the "open" position to the "closed" position when the catacates 7 and 8 are closed. The level of level corresponds to the movement by points 4,5,6.1 static characteristics.

Integral regulators

Automatic regulators, in which the same value of the adjustable value may correspond to various positions of the regulatory body, called integral or astatic (astatos. - Unstable, restless).

The speed of moving the regulating organ of these regulators, the greater, the greater the deviation of the adjustable value from the specified value.

Consider the principle of the operation of the regulator on the example of the concept of a hydraulic and regulator of an indirect action (Fig. 7.3). When changing pressure p. The pipeline changes the pressure on the bellows 1, the bottom of which moves, which leads to the rotation of the ABC lever relative to the point A and the movement of the spool's pistons 2 up or down. When p. More given, then the bottom of the bellows will move down, the ABC lever will turn clockwise, the spool pistons will also be released down and the oil under pressure comes from the chamber e. Cylinder of the spool device in the cavity m. Cylinder of the executive mechanism 7. Piston of the executive mechanism (im) linked to the rod with the regulatory body (Sewber) 6 will begin to move upwards by increasing the degree of opening of the chiber; It will lead to a decrease in the pressure p.. As a result of a decrease in pressure, the bellows 1 squeezed, returning the ABC lever in its original position, the spool pistons overlap the oil access to the cylinder, the control action stops.

During the movement of the piston to them up the oil from the cavity n. The cylinder is supplanted through the tube through the chamber d. the cylinder of the spool device and is triggered to drain 5. The oil is cleaned and is re-fed into the chamber e. Special pumping installation.

Fig. 7.3 Circuit diagram and regulator of indirect action:

1-silder; 2-spool; 3-supply oil under pressure; 4,9-valves; 5-plums of oil; 6-regulating body; 7-efficient mechanism; 8 caster.

Assuming that pressure p. It became lower than the predetermined, then the bottom of the bellows 1 will move up, the ABC lever will turn counterclockwise, moving the spool pistons up, and the oil through the half e. will go to the cavity n. Cylinder them. It will lead to the closure of the pair and increase pressure p.. At the same time, the oil from the cavity of the cylinder them through the cavity f. The cylinder of the spool device enters the draining.

The specified value of the adjustable value is installed with the help of the depositter 8. When the force developed by the bellows and the spring of the model is equal to the ABC lever is in a neutral position and the chamber oil e. Does not go to the cylinder them.

In and regulators, there are no feedback, they are simple on the device. The most important feature is that, regardless of the load of the adjustable object, they lead the adjustable value to the specified value. And regulators have some disadvantages due to their dynamic properties. A small deviation of the adjustable value from the specified value, and the regulator continue to move the regulating body up to the position of the full opening or closing. The direction of the RO movement occurs only when the adjustable value passes the specified value.

The law of regulation involves the effect of the regulator at a rate proportional to the deviation of the adjustable value, and is described by the equation

Here S. 0 - Specially calculated adjustment parameter of the regulator. The minus sign means that with a positive deviation of the adjustable value of PO moves towards the closure, and with a negative deviation (the decrease against the specified value) is in the direction of opening.

The equation of the regulator in the integrated form:

The transfer function of the regulator has the form

In Figure 7.4, and the static characteristic of the and regulator is shown. When adjustable value y. Below the specified value regulating ? Located in the extreme lower position. As soon as the adjustable value reaches the specified value, the PO will begin moved towards the opening and can stop at any point of the vertical segment of the characteristics.

Starting from the moment t. 0 when adjustable value y. It has changed abruptly, RO moves at a constant speed, changing the inflow (Fig. 7.4, b).

Fig. 7.4 Characteristics and - regulators:

a- static; b-curve overclocking; Principal process.

As a result of the controller, the adjustable value y. comes to a given value after a while t. r called time regulation; Moreover, the transition process is oscillatory, attenuating (Fig. 7.4, B).

And the regulator is applied only in self-leveling systems, otherwise the system will be unstable.

Fig. 7.5 Schematic diagram (a) and dynamic characteristics (b) and direct actuator:

1-pipe; 2-load; 3 lever; 4 membrane; 5th rod; 6-regulating body; 7-housing; 8-pulse line; 9-valve.

Figure 7.5, and the scheme of the direct action is shown. On pipeline 1 with flange and bolt connections The body has been strengthened Regulator 7. If the adjustable value is pressure p. After the regulator, it will change, the change in pressure through the pulse line 8 and the valve 9 will be transmitted to the membrane 4 of them associated with PO 6 using Stem 5. At the point m. There is a hinge connecting the rod with the lever 3, on which the load 2 is strengthened, which is a master device. Adjustable Davlya p. Depends on the influx of the medium, i.e. on the degree of opening PO 6. When p. Equally a given value, an effort developed by membrane 4 and cargo 2 are equal, and the rod 5 is fixed. With an increase in or reducing the pressure compared to the throat and PO 6, it will be moved, respectively or up. The replacement rate is proportional to the deviation of the actual value of the adjustable pressure from the specified.

As can be seen from the graph (Fig. 7.5, b) when the load changes x. Object at the moment t. 0 Begins to change the adjustable value y. and move the regulator. Changing the movement of the regulatory organ occurs at the moment of change of the sign of the adjustable value (points t. 1 T. 2 ).

Proportional regulators

Automatic regulators in which the deactivation of the adjustable value from the specified value causes the movement of the regulatory body by the value, the proportional value of this deviation, is called proportional, or static (statos. -standing). Each value adjustable parameter It corresponds to one specific position of the regulatory body. This proportional dependence is achieved by the action of a tight feedback, therefore the P-regulators are also called tight feedback regulators. The movement rate of the regulatory body of such regulators of proportionally rate of changes in the adjustable value. P-regulators as integral, can be indirect and direct action.

The P-regulator circuit (Fig.-7.6) differs from the diagram of the and regulator by the fact that the ABC lever does not have a hinge at a point A, and with a row 8 connected to the piston 7. This connection and form a rigid feedback.

As a result of an indignant impact, which leads to an increase in pressure p. In the pipeline, the point with will move to position with ", and the point B to the position in" - and the lever will take the position of AV "C". At the same time, the pistons of the spool 2 are mixed down and the oil will begin to flow into the cavity m.the cylinder of the actuator, moving the piston, and in place with it and the regulating body 6 up. Along with the piston, the position A is changed to the position A "(Up) the left end of the ABC lever, the point B will be returned to the value of the spool 2 return to its original position, connect the oil access to the actuator. This will end in this process.

Fig. 7.6 Concept scheme of an indirect action P-regulator:

1-silder; 2-spool; 3-input of oil under pressure; 4-valve; 5-plums of oil; 6-regulating body; 7-use mechanisms; 8-rod; 9-max.

The measuring unit (siltphone 1) and the feedback mechanism affect the RO almost simultaneously. Therefore, the movement of the RO should be considered as the basis of the measuring system, reduced to some kind of feedback.

The speed of the P-regulator than the regulator, relatively quickly stabilizes the process and leads the system into an equilibrium state.

The simplest static regulator is an amplifying link and is described by the equation

Here S. 1 -stand parameter (amplification coefficient) of the P-regulator.

P-regulator gear ratio

;

Fig. 7.7 Characteristics of the P-Regulator:

a-static; b-curve overclocking; in transient processes;

1-static error is small; 2-static error is somewhat larger; 3-static error big.

Static and dynamic characteristics of the P-regulator are shown in Fig. 7.7. From the static characteristics family (Fig. 7.7, a), it can be seen that RO begins to move only when the adjustable value of the lower limit of proportionality is reached. Suppose that the adjustable value corresponds to 50% of the regulator scale, and the limit of proportionality is 40% configured ( d.\u003d 40%). The regulator occupies the average position ( d.\u003d 50% stroke). This position corresponds to the point A on the characteristic. If now the adjustable value will start increasing, the regulatory body will move towards closing.

The overclocking curve of the P-regulator (Fig. 7.7, b) is similar to an amplifying link. If at the time of time t. 0 Adjustable value y. It will change hype (for example, it will increase), the regulatory body will also be tormented back ( m.) In the closing storage.

On the characteristics of transient processes in the automatic system with a P-regulator, the established limits of proportionality are influenced. With increasing gain coefficient S. 1 , or, that is the same, with a decrease in the limit of proportionality ? The transition process proceeds in the form of slowly attenuating oscillations, and static error Y. art It is small (Fig. 7.7, in curve 1). With an optimal gain factification for this object S. 1 The transition process quickly fades, but static error Y. art somewhat increasing (Fig. 7.7, in curve 2). If the amplification coefficient S. 1 Dumps are small ( d.-Lell), the transition process can become aperiodic with a large static error (Fig. 7.7, in curve 2).

The value of a static error depends on both the adjustment of the regulator and the characteristic and mode of operation of the object. Setting the regulator to the required value d. (Fig. 7.6) is exadected by changing the ratio of the shoulder BC and AB lever ABC. The less AB, the more ? .

Proportional regulators can be used to control processes occurring in objects, both possessing and not possessing self-leveling. It should be borne in mind that the load changes must be small to allow the static error to remain in permissible limits.

Fig. 7.8 Schematic diagram (a) and dynamic characteristics (b) direct-acting P-regulator:

1-pipe; 2-fabric; 3-screw; 4-spring; 5th rod; 6-regulating body; 7-pulse line; 8-housing.

In fig. 7.8 shows a direct-acting P-regulator. In contrast to the and regulator, in a direct-acting p-regulator, an effort developed by the membrane is not equalized by non-cargo, but 4; the greater the pressure deviation p. from a given value, the stronger the membrane begins, but the dense of the spring is compressed, counteracting the deflection; This achieves the proportionality between the adjustable value and the movement of the RO.

When carrying the load Q object at the time of time t. about Adjustable value Y. increases, but, thanks to the movement of the regulatory body towards closing, after a while t. r It stabilizes (Fig. 7.8, b). However, due to the static error, its value will differ from the specified value to Y. mouth.

Proportional and integral regulators

A comparison of P-regulators and and regulators shows that the first has an advantage over dynamic properties and ensure the best transition process of regulation; The advantage of the second is the presentation of a static error, i.e. The best static properties.

Pi - the regulator combines both P and and regulators. In fact, the same as the regulator is isodromic (from Greek isos. - equal, similar; dromos.- Running) The regulator supports the constant value of the adjustable value, regardless of the load of the object, and when it deflects it from a given value, in the initial moment of time, the regulatory body will move by a value proportional to the deflection value (as a P-regulator), will then continue to move the regulatory organ before static Error, i.e. will lead the adjustable value to the specified value.

Pi-regulator are indirect control regulators. The schematic diagram of the Pi-regulator of the hydraulic type is shown in Fig. 7.9.

In the initial period, the regulator works as proportional. With an increase in adjustable value (pressure p.) The piston of the actuator 7 and the regulating body 6 will begin to move upwards. The piston of them 7 are connected to a point and the ABC lever is not rigidly (as in the regulator), but through the isodroma devices, which consists of a cylinder 9 filled with oil, piston 8, rigidly connected rod with a piston 7, needle valve 12 installed on the overflow line oils from cavities G and H and spring 10, counteracting the movement of point A.

With a relatively rapid movement of the piston 7, the cylinder 9 and the piston 8 are also moved up as one whole, because The flowing section of the choke 12 is small and the oil does not have time to pull from the cavity G to the cavity H. Point A ABC lever moves up, the spring 10 is compressed, and the pistons of the spool device returns to its original position, stopping the supply of oil into the cylinder. The regulator worked as proportional, but its action was not over. Spring power 10 applied to the cylinder 9 at point A, will make the latter move down relative to the fixed piston 8; At the same time, the oil from the cavity G will begin to flow through the valve 12 to the cavity H. Point and starts down down, the point in also goes down and this will lead to an additional triggering to them, i.e. To the additional movement of PO up.

The controller will stop when the spring 10 is spent all its energy, i.e. When the adjustable value of the specified value is reached. Naturally, the speed of the isodromic component of the regulator will depend on the degree of opening of the valve 12.

Fig. 7.9 Schematic diagram of the Pi-Regulator of the indirect Dixia:

1-silder; 2-spool; 3-input of oil under pressure; 4-valve; 5-plums of oil; 6-regulating body; 7-use mechanisms; 8-piston; 9-cylinder; 10-spring; 11-depositchik; 12-needle valve.

Pi - regulators can be applied in cases where high control accuracy is necessary for objects of any container both in the presence and in the absence of self-leveling, with large, but smooth load changes.

Pi-Regulator acts faster than and regulators, but slower than P-regulators.

The PI regulator equation has the form:

.

The transfer function of the PI regulator has the form:

Fig. 7.10 Pi-regulator features:

a-static; b-curve overclocking; B-curves of transitional processes; M-curves forced transition processes for pi- and regulators: 1-5 points, which are characteristic of the regulation of the regulatory body; 6-10 - curves of transition processes.

The static characteristic of the PI regulator is shown in Fig. 7.10. Let the regulator are configured so that when the adjustable value is changed y.constituting from 20 to 80% of the scale regulating the body moves from one extreme position to another ( d. \u003d 60%), and let the system be at the beginning in equilibrium condition Y.\u003d 50% and m.\u003d 50% (points 1 and 2). Suppose that the adjustable value jumps up to 60% of the scale (point 3). Then due to the impact of the proportional component of the regulator, the position of the regulatory body will quickly change and will reach about 68% of its stroke (point 4). Then the heodroma assembly will begin to slowly, which will return the adjustable value to the specified value (point 5); The effect of the regulator will stop at the new position of the regulator (point 5 ") corresponding to about 73% of the stroke. Since the limit of proportionality does not change in the process of operation of the regulator, it can be concluded that it seems to be a static characteristic in parallel (dotted line).

As can be seen from the curve of overclocking the pireloutor (Fig. 7.10, b), with a jump-like perturbing effect (sharp decrease in the adjustable value) at the time T 0, the regulatory body is quickly moved by magnitude DM. Under the action of the proportional component. It will then continue to move in the same direction at a constant speed (line AB) under the action of the isopromic component. If in the regulator scheme (see Fig. 7.9) the heodrome choke 12 is closed ( T. i.), the controller works as proportional and its characteristic is the dotted line of the speakers in Fig. 7.10, b. The more is the heodrome choke, i.e. the less time is the isoo T. i. The greater the speed of moving the regulatory body, i.e. the steeper line Av.

In Fig. 7.10, the curves of forced transient processes are depicted with different adjustment of the gain coefficient S. 1 and time T. i. Regulator. Curve 6 corresponds to the transient process when too large S. 1 or with too small T. i.. The time of the transition process is large, the oscillations fade slowly. Curve 7 represents the optimal transition process. Curve 8 corresponds to the process with a too small gain or too much isodroma. The aperiodic process is slowly, the adjustable value is slowly returned to the specified value.

Differential regulators

Differential regulators are two types of PD proportional and differential and PID-proportional-integral-differential.

Such regulators should be applied in cases where the load of control objects changes often and quickly, and the delay is large. The PID regulator equation is:

.

Here S. 2 - The setting parameter of the regulator, which takes into account the rate of change of the adjustable value in time.

The transfer function of the PID regulator has the form:

.

Differential regulators are called regulators with prevention. The essence of premium (excluding delay) is sworn as follows.

Let an adjustable parameter y. varies by exponential 1 (Fig. 7.11, a). The first derivative of the parameter (curve 2) is a tangent of an inclination angle to the appropriate exponential point 1 and has the maximum value at the initial moment when the parameter is just started to change, and at the moment t. 1 When the change stops, zero.

Fig. 7.11. Characteristics of the regulator with the preview

a-transition process (1) and its derivative (2); b, in-options for the change of regulatory organ; I-for P regulator; II-for d regulator.

The effect of premium can be determined so. If the adjustable value y.(Fig. 7.11, b) will change its value by value A, then the output signal of the regulator m.supplied to the regulating body will have a character corresponding to a solid curve. For comparison, the dotted line shows the action of the P-regulator. In the process of regulating in the regulators, with prevention, there is a change in the limits of proportionality. And at the beginning, this deviation is sharp, and then it comes to a tuning value.

With a continuous change in the adjustable value y,since the time of time t. 0 (Fig. 7.11, B), the regulator of the P-regulator will move according to the dotted direct direct I., and at the d-regulator, according to a solid line II.. The regulator seems to prevent the expected deviation of the parameter. Time premium T. p Determines the relative value of an additional signal according to the derivative (it is associated with a tuning parameter) and is usually adjusted in the range from 0.1 to 1 min.

The controller's action with premises is considered on the example of temperature control in the control object, where hot gas is used as a coolant (Fig. 7.12, a).

Fig. 7.12 Concept of the regulator with prevention (a) and graph of transition processes PI and PID regulators (b):

Or-object of regulation; 1-3 - thermocouple; R is the parameter retake; EU amplifier; RD-reversible engine; The regulatory authority.

The device that performs the action with the prevention consists of those thermocouple 1, 2, 3, which are a sensitive element of the regulator. Thermocouples 1 and 2 are included in consistently (their thermo EMF is folded), and the thermocouple 3 is on the ones (its thermo EMF is deducted from the sum of the first first). The mass of hot spoof thermocouples 3 is much larger than the mass of spa each of the first two. In a state of thermal equilibrium, all three spoys have the same temperature and extend equal to the TADS. The total TADS of such a battery will be equal to the TADS of one of the thermocouple 1 or 2.

If adjustable temperature t. The control object will begin to change at a certain speed, then the TADS of the first two thermocouples will reflect these changes at the same speed, and the change in the thermocouple 3 TDS will lag behind the first and second, the greater the greater the difference in the mass of hot spa thermocouple 1 and 2, on the one hand , and thermocouples 3 - on the other, as well as the more temperature change rate.

Thus, thermocouple 1 produces a signal proportional to the most adjustable value (temperature t.), and thermocouples 2 and 3 - a signal, proportional to the amount of its change ( t.).

Resulting TADS of all three thermocouples u. Compared with a voltage drop u. about on resistance r. Master, which is proportional to the specified value of the adjustable value. Term Battery of three Termaar and Power Supply u. z. The depositchy is designed. In violation temperature mode In the object on the input of the electronic amplifier EU comes the signal D.u \u003d U. about - u., and at first moment the value of the signal is significant and the reversible engine of the RD intensively moves RO, dramatically changing the flow of the coolant, and then when the signal D.u.By reaching a maximum, it will begin to decrease, the reversing engine will begin smoothly move the PO to the other side, reducing the flow of the coolant and leading the parameter to the specified value.

In fig. 7.12, B shows a graph of transient processes for PI and PID of regulation laws.

Choosing a type of regulator

The task of the designer consists in choosing this type of regulator, which, at minimum cost and maximum reliability, would provide a specified quality of regulation.

To select the type of regulator and determine its settings, you need to know:

· Static and dynamic characteristics of the control object.

· Requirements for the quality of the regulatory process.

· Regulatory quality indicators for serial regulators.

· The nature of the perturbations acting on the regulatory process.

The choice of the type of regulator usually begins with the simplest two-position regulators and may end with self-adjusting microprocessor regulators.

Consider the quality indicators of serial regulators. Continuous regulators that implement the laws of management and, P, PI and PID are assumed as serial.

Theoretically, with the complication of the law of regulation, the quality of the system is improved. It is known that the magnitude of the retardation ratio to the permanent time of the object is known for the regulatory dynamics. The effectiveness of compensation for step perturbation by the regulator is fairly accurately characterized by the value of the dynamic regulation coefficient R d, and the speed is the magnitude of the regulation time. Theoretically, in the system with delaying, the minimum control time T pvin \u003d 2 /.

The minimum possible regulatory time for different types of regulators with optimal configuration is determined by Table 1.

Table 1

Guided by the table, it can be argued that the greatest speed provides the Law of the Office of P. However, if the gain of the KP P-regulator is small (most often it is observed in systems with delay), then such a regulator does not provide high control accuracy, since in this case The magnitude of the static error. If KP has a value of 10 or more, then the P-controller is acceptable, and if KP<10 то требуется введение в закон управления интегральной составляющей.

The most common practical is a Pi-regulator, which has the following advantages:

1. Provides a zero static control error.

2. It is fairly simple in the setting, since only two parameters are configured, namely the gain coefficient k p and the integration constant T i. In such a regulator, it is possible to optimize K P / T I\u003e MAX, which provides control with the minimum possible range of regulation error.

3. It has a small sensitivity to noise in the measurement channel (unlike the PID controller).

For the most responsible contours, it is possible to recommend the use of the PID regulator, which ensures the highest speed in the system. However, it should be borne in mind that this condition is performed only when it is optimal settings (three parameters are configured). With increasing delay in the system, negative phase shifts increase sharply, which reduces the effect of the differential component of the regulator. Therefore, the quality of the work of the PID regulator for systems with large delay becomes comparable to the quality of the PI regulator. In addition, the presence of noise in the measurement channel in a system with a PID controller leads to a significant random fluctuations in the control signal of the regulator, which increases the dispersion of the control error. Thus, the PID controller should be chosen for regulating systems with a relatively low level of noise and lag in the control object. Examples of such systems are the temperature control systems.

When the type of regulator is selected, it is recommended to navigate the value of the delay ratio to a constant time in the object / t. If / T.< 0,2, то можно выбрать релейный, непрерывный или цифровой регуляторы. Если 0,2 < /T< 1, то должен быть выбран непрерывный или цифровой, ПИ или ПИД-регулятор. Если /T >1, then choose a special digital regulator with a flambery that compensates for delay in the control circuit. However, the same regulator is recommended to apply with smaller relations / t.

Formular method for determining the settings of the regulator

The method is used to quickly approximately estimate the values \u200b\u200bof the regulator setting parameters for the three types of optimal type control processes.

The method is applicable both for static objects with self-leveling (Table 2) and for objects without self-leveling (Table 3).

Note: T, K OU - time constant, delay and gain of the object.

In these formulas, it is assumed that a regulator with dependent settings is configured, the transfer function of which has the form:

where: k p is the gain of the regulator;

T i - levels of isoorom (constant integration of the regulator);

T d - distance premium (constant differentiation).

Calculation of settings on the frequency characteristics of the object

There is a special equipment for experimental determination of the amplitude-phase characteristic (AFC) of the control object: this characteristic can be used to calculate the PI regulator settings, the GD of the main criterion is to ensure the specified stability reserves in the system.

Sustainability reserves are conveniently characterized by an indicator of the oscillativity of the system M, the magnitude of which in the system with a PI regulator coincides with the maximum amplitude-frequency characteristic of the closed system. In order for this maximum to not exceed a given value, the AFC open system should not enter the circumference with the center P 0 and the R radius, where

It can be proved that the optimal minimum of the standard setup error will be such in which the system with an oscillativity indicator MM 1 will have the highest coefficient with an integral component that corresponds to the K P / T I\u003e MIN condition.

In this regard, the calculation of optimal settings consists of two stages:

1. Finding in the plane of the parameters k p and t i, the boundaries of the area in which the system has a specified parameter indicator M 1.

2. Determination at the boundary of the area of \u200b\u200bthe point satisfying the requirement K P / T I.

Calculation of settings on the frequency characteristics of the object. Methods for calculating the settings of the pi regulator on AFC object

1. A family of amplitude-phase characteristics of an open system of an open system at k p \u003d 1 and various values \u200b\u200bof T IJ (5 -6 values) are constructed.

2. The values \u200b\u200bof the oscillativity indicator M are set from the range of 1.55 m 2,3 (recommended M \u003d 1.6). From the beginning of the coordinates, there is a straight OE at an angle \u003d arcsin (1 / m 1), where M 1 is the selected value of the oscillating indicator.

3. A family of circles concerning AFC OJ and direct OE at an angle are built, and the center of the circles is all the time on a negative actual axis. As a result of the construction, the radii of these circles R j is determined.

4. For each circle, calculate the limit value K p

5. According to the values \u200b\u200bof K pj and k IJ build the boundary of the area of \u200b\u200bthe specified oscillating indicator.

6. At this border determine the point for which the ratio K p / t I is maximally.

Experimental adjustment methods

For a significant number of industrial control objects, there are no fairly accurate mathematical models describing their static and dynamic characteristics. In the time, the experiments on the removal of these characteristics are very expensive and laborious.

The experimental method of adjusting the regulators does not require knowledge of the mathematical model of the object. However, it is assumed that the system is mounted and can be run into operation, and there is also the possibility of changing the regulator settings. Thus, we can conduct some experiments to analyze the effect of changes in the system dynamics. Ultimately guarantee good settings for this control system.

There are two methods of tuning - the method of unlucky oscillations and the method of sputtering oscillations.

Method of unsuccessful oscillations

The operating system turns off the integral and differential components of the regulator (t i \u003d, T d \u003d 0), that is, the system is translated into the law of regulation P.

By a sequential increase in K p with a simultaneous supply of a small jump-shaking signal of the task, it seems to occur in the system of unlucky oscillations with a period of T KP. This corresponds to the removal of the system to the boundary of oscillatory stability. If this mode occurs, the values \u200b\u200bof the critical gain of the K KP regulator and the period of critical oscillations in the T KP system are recorded. With the appearance of critical oscillations, no variable system should go to the level of restriction.

By values \u200b\u200bof T KP and K KP, the regulator settings are calculated:

· P-regulator: k p \u003d 0.55 K kp;

· Pi-controller: k p \u003d 0.45 K kp; T i \u003d t kp / 1,2;

· PID controller: k p \u003d 0.6 k kp; T i \u003d t kp / 2; T d \u003d T KP / 8.

Calculation of the settings of the regulator can be made by the critical frequency of the control object of P. Considering that the own frequency P OO coincides with the critical frequency of oscillations of the closed system with a P-regulator, the values \u200b\u200bof T KP and K KP can be determined by amplitude and period of critical oscillations of the control object .

When removing a closed system to the boundary of oscillatory stability, the amplitude of oscillations may exceed the permissible value, which in turn will lead to an emergency at the facility or to the release of defective products. Therefore, not all control systems for industrial objects can be derived for critical mode.

Method of fading oscillations

The use of this method allows you to configure regulators without removing the system to critical modes of operation. Just as in the previous method, for a closed system with a P-regulator, a consecutive increase in KP is achieved by the transition process for the development of a rectangular pulse along a set of task or perturbation with a decrement of attenuation D \u003d 1/4. Further, the period of these oscillations T k and the values \u200b\u200bof constant integration and differentiation of the t i, t d regulators are determined.

· For PI regulator: T i \u003d T k / 6;

· For PID controller: T i \u003d T k / 6; T d \u003d T k / 1.5.

After installing the calculated values \u200b\u200bof T I and T D, it is necessary to experimentally clarify the value K p to obtain the attenuation decrement D \u003d 1/4. For this purpose, an additional adjustment is made for the selected regulatory law, which usually leads to a decrease in k p to 20 -30%. Most industrial regulatory systems are considered qualitatively configured if their attenuation decrement D is 1/4 or 1/5.

Regulation with noise

The presence of high-frequency noise components in the measuring signal leads to random fluctuations in the actuator mechanism, which increases the dispersion of the control error and reduces the accuracy of the regulation. In some cases, strong noise components can lead the system to an unstable operation mode (stochastic instability).

IN industrial systems The measuring circuits often contain noise associated with the frequency of the supply network. In connection with this, an important task is the correct filtering of the measuring signal, as well as the selection of the desired algorithm and the parameters of the regulator. This uses low high-order low frequency filters (5 -7), having a greater steepness of the recession. They are sometimes embedded in normalizing converters.

Thus, the main task of the regulator is the compensation of low-frequency perturbations. At the same time, in order to obtain the minimum dispersion of the control error, high-frequency interference must be filtered. However, in general, this task is contrary to, since the spectra of perturbation and noise can be superimposed on each other. This contradiction is permitted using the theory of optimal stochastic management, which allows you to achieve good speed in the system with a minimally possible dispersion of the control error. To reduce the effect of interference in practical situations, two methods based on:

· Reduction of the gain of the K P regulator, that is, in fact, the transition to the integral regulation law, which is simpless to noise;

· Filtering of the measured signal.

Methods for setting up two-joil control systems

Of the total number of regulatory systems, about 15% are two-bond regulatory systems (Fig. 11). In such systems, even with the sustainable autonomous work of two regulators, the entire system can become unstable by the action of cross-links in the control object.

The control object in a two-beam system is represented in a r-canonical form. The convenience of such a representation is that by active experiment, you can define all gear ratios on the relevant channels. Intermediate signals x 1, x 2, x 3, x 4 are usually not available for measurement, so control is conducted via the y output vector:

In practice, a rather large number of systems are two-beyond. For objective configuration of two-joys system regulators, a quality quality criterion is formed:

where Y 1 and Y 2 are the coefficients of weight (fine), J1 and J 2 - the quality criteria of the first and second circuits.

By redistributing weight coefficients Y 1 and Y 2, you can select a more important circuit, the quality of the control processes in which should be higher. For example, if the first circuit should provide higher accuracy of work, then Y 1 is required to increase.

Military regulators

Schemes for the operation of the ignite regulator of the frequency of rotation of the VE fuel pump with the levers and operating positions of the dosing clutch on various load and high-speed modes are shown in the drawings A, B, B, G.

Fig. Operation of the All-Term Regulator: A - Starting Position; b - idling minimum mode; B - load reduction mode; g - load increase mode; 1 - cargo regulator; 2 - Coupling regulator, 3 - power lever; 4 - Purpose lever, 5 - Spring of the launcher; 6 - dosing coupling; 7 - shut-off holes in the plunger; 8 - plunger; 9 is an adjusting minimum switching screw; 10 - control lever; 11 - the adjusting screw of the maximum mode; 12 - axis control lever; 13 - the working spring of the regulator; 14 - springs retainer; 15 - Spring minimum mode; 16 - emphasis of the power lever; M2 - axis of rotation of the levers 4 and 5; H, and H2 active prunes in various modes

Cargo regulator 1 (usually four loads) are installed in the holder that gets rotation from the drive gear. The radial movement of goods is transformed into the axial movement of the coupling of the regulator 2, which changes the position of the pressure 4 and the power 3 of the regulator levers, which turning relative to the M2 axis. Move the dosing coupling 6, thereby determining the active stroke of the plunger 8.

In the upper part of the power lever, the idling spring is installed, and between the power and pressure levers - the lamellar spring flow 5. The control lever 10 affects the operating spring of the regulator 13. The second end of which is fixed in the power lever on the retainer 14. Thus. position of the lever system and. Consequently, the dosing clutch is determined by the interaction of the two forces - the pre-tightening force of the working spring of the regulator, determined by the position of the control lever, and the centrifugal force of cargo shown in the coupling.

Regulator operation when starting a diesel engine

Before launching a diesel engine, when the crankshaft does not yet rotate and the fuel pump does not work, the loads of the regulator are at rest at a minimum radius, and the pressure lever 4 (its other name is the start lever) under the action of the spring supply spring 5 is shifted to the left in Figure A, Having the possibility of swing relative to the M2 axis. Accordingly, the lower hinge end of the lever provides an extremely right position of the dispenser 6 relative to the plunger 8. What corresponds to the start-up feed due to the increased active movement of the H1 plunger. As soon as the engine starts, the load of the regulator diverges and the coupling 2 moves to the right to the value of "A", overcoming the resistance of a sufficiently weak trigger spring 5. The lever 4 is rotated on the M2 axis clockwise by moving the dosing clutch towards reducing the feed. Fig. b).

The operation of the regulator at the minimum speed of the idle rotation

In the absence of a load and position of the control lever at the stop in the adjusting screw 9, the diesel should work steadily at the minimum speed of the idle speed in accordance with the scheme of drawing b. The regulation of this mode is provided by a non-stroke spring 15. The force of which is in equilibrium with centrifugal power of goods, and as a result of this equilibrium, the fuel supply corresponding to the active move of the H2 plunger is maintained. The operation of a diesel engine in this mode corresponds to point 5 on the characteristic of the first pattern. As soon as the high-speed engine mode goes beyond the minimum speed of the idle turn, the course "C" of the power lever is being implemented when the spring 15 is compressed under the action of the increasing centrifugal force of goods.

The operation of the regulator on load modes

In the operation of a diesel engine with a sever-mode regulator, the speed mode is installed by the driver by exposure through the accelerator pedal to the control lever 10. On the working modes of the starting feed supply spring 5 and the 4-cold spring spring, the controller is determined by the preliminary deformation of the working spring 13. When turning the control lever before The stop 11 (drawings in, d) in the direction of increasing the speed mode and the corresponding stretching of the working spring is transmitted to the power lever 3 and then through the lever 4 on the clutch of the regulator 2, forcing the loads 1 to converge. The lever system is rotated relative to the M2 axis counterclockwise in the figure, moving the dosing clutch 6 in the direction of increasing the feed to the outer high speed modes. The speed of rotation of the crankshaft diesel and, accordingly, the regulator cargo increases, the centrifugal power of cargo and the resistance of the last effort of the working spring also increase, and at some point there is an equilibrium of the forces and the equilibrium of the position of all elements of the regulator. If there is no change in load, the engine operates on steady mode at a constant speed of rotation (without taking into account the nonstability of rotation natural for LAN).

If there is a change in the load in this mode, the automatic regulator is entered into operation in accordance with the schemes shown in the drawings in C, G. With a decrease in load, the speed frequency increases, the regulator's loads are diverged and, overcoming the resistance of the working spring, move the knob to the right (drawing in). The lever system is rotated relative to the M2 axis clockwise by moving the dosing clutch to the left, towards reducing the feed. As a result, the regulatory branch of 4 is formed on the first drawing. If the control lever is set to a certain intermediate position, then, compared with the adjustment of the regulator shown in drawings in, g, one of the regulatory characteristics shown by the dotted line on the first figure B, i.e. The regulator in the latter case starts working earlier - with a lower rotation frequency.

In Figure G, the operation of the regulator is shown when the control lever is shown at the stop 11 and with an increase in the load. In this case, the rotational speed of the diesel shaft decreases, the cargo of the regulator converge, the centrifugal power of goods decreases, and under the action of the work spring of the regulator's coupling, moves to the left, and the lever system 3 and 4 moves the dosing coupling to the right, towards increasing the feed. If the diesel is started before the load increases, it worked on the regulatory branch, then with an increase in the feed, it will go to the more powerful mode and then to the outer speed characteristic. If the diesel is operating on an external characteristic on nominal or close to it, then with an increase in the load, the overload mode is realized, to overcome which the diesel should have a fairly high adaptability coefficient. Positive adjustment of fuel feeds is carried out on the section 3 of the characteristics using a positive corrector or with the corresponding selection of the fuel-feeding characteristics of the TNVD.

Correctors of fuel supplies

Adjusting fuel supplies in diesel glands, positive or negative, is carried out in order to form an external high-speed engine characteristic if necessary, increase the maximum torque by increasing the feed when the rotational speed is reduced to Nm on the so-called overload mode (positive adjustment) or reduce diesel smoke when working on N.< nm по внешней скоростной характеристике. Влияние корректирования на протекание внешней скоростной характеристики дизеля показано на рисунке ниже. Положительное корректирование необходимо для обеспечения заданного запаса крутящего момента двигателя.

Fig. External Diesel Characteristic: Me - Torque, N - Rotation Rotation Frequency, NM - Rotation Rotation Rotation Species, NY - Rotation Rotation Rotation Frequency, N Min - Minimum Rotation Rotation Overward Specifications

Correction of the characteristic may be implemented by a pressure valve or mechanical corrector in the regulator. With the help of a mechanical corrector, negative adjustment is also carried out. The latter is usually used in engines in order to reduce soot emissions.< nм1, а также в двигателя с турбонаддувом и ТНВД без корректора по давлению наддува, т.е. без ограничения подачи в системе LDA.

Work of positive and negative proofreaders

The device and operation of positive and negative mechanical proofreaders of the fuel fuel fuel pump VE are illustrated in Fig. a, b.

Fig. Regulator circuit with positive (a) and negative (b) fuel corrector: 1 - launcher lever; 2 - springs of proofreaders; 3 - the working spring of the regulator; 4 - power lever 5 - emphasis; 6 - proofreaders levers; 7 - Corrector rod; 8 - dosing coupling; 9 - Pad Spring; 10 - Coupling regulator; 11 - the point of the stop; Mg - axis of rotation of levers 1 and 4; M4 - axis of rotation of levers 1 and 6; ΔS - feed adjustment course

The beginning of the direct (positive) fuel corrector is determined by the rigidity and preliminary compression of its springs, which are consistent with the corresponding speed diesel mode. The work of the positive corrector occurs as follows. On the nominal mode, the dosing coupling 8 occupies a position indicated by a dotted line in Fig. but. The spring of the corrector 2 is compressed due to the effects of centrifugal forces of goods through the clutch 10 of the regulator on the lever 6, which presses on the head of the stock 7, turning on the stop 5 in the power lever 4. The lever 1 is rotated clockwise and the dispenser provides cyclical feed which meets the requirements of the nominal diesel mode (see the dotted line in Fig. A). If the load in this mode increases (overload mode), the speed of rotation is reduced, the force of the regulator clutch is also decreased, and the spring 2 of the lever 6 turns the lever 1 counterclockwise by moving the dosing clutch to the right, towards increasing the feed by ΔS ( Fig. a).

The work of the negative corrector

When working with a minimum frequency on the external characteristic of the lever 6 of the corrector rests in the power lever at point 5 (Fig. B). The head head 7 of the corrector is also resting in the power lever 4. With an increase in the speed of rotation, the centrifugal force of cargo shown to the clutch, overcomes the force of the spring of 2 corrector, squeezing it. As a result, the lever 6 moves to the right in the figure, towards the head of the rod, while the total axis of the M4 levers changes its position. At the same time, the lever 1 turns relative to the M2 axis by moving the dosing clutch 8 to the increase in the feed. The progress of the adjustment ΔS is determined by the progress of the compression of the corrector's spring until the lever is stopped into the stem head 7. When the diesel engine is operating on the left side of the external speed characteristic, with an increase in the load and reduce the speed of the spring 2 turns the lever 6 clockwise, and the latter causes the lever 1 relative to the axis M2 clockwise by moving the dosing clutch 8 in the direction of decrease in the feed, thus carrying out negative adjustment (Nine region< n < nм на рисунке).

Double-mode regulators

The device of the two-mode automatic regulator of the rotational speed of the VE fuel pump and its operation in various modes are shown in the figures below having a common specification. The regulator shaft receives rotation from the TNLD shaft through a gear increases with a gear ratio of 1: 1.6 and transmits it to the four cargo holder.

A similar design of this node has VE fuel pumps with all-mode regulators, discussed above.

The magnitude of the fuel feeder changes with a change in the position of the dosing clutch 15, which is determined by the equilibrium of the centrifugal force of cargo shown in the coupling, and the force from the action of the operating springs of the regulator, depending, in particular, on the position of the accelerator pedal.

Diesel start mode is shown in the figure. With a non-working engine, the loads of the regulator are reduced and the coupling 19 is in the extreme left position. The lever of the corrector 16 and the starting lever 18 is pressed under the action of the spring supply springs 12 to the clutch of the regulator 19, turning relative to the M2 axis. Thus, the dosing clutch 15 moves by the lower hinge of the lever system to the right in the figure below, providing a start-up. The accelerator pedal with a dyel start can remain in a non-fire position. The magnitude of the starting feed is determined by the active course of ΔS1.

Fig. Dual-mode regulator circuit. Diesel start mode: 1 - cargo holder; 2 - cargo regulator; 3 - earring; 4 - axis control lever; 5-Spring of the nominal mode; 6 - partial mode spring; 7 - adjusting screw maximum feed; 8 - damper spring; 9 - non-minimal mode of idling; 10 - power lever; 11 - adjustment lever; 12 - Spring of the launcher; 13 - Supporting spring; 14 - PTNVD plunger; 15 - dosing clutch; 16 - lever of the negative corrector; 17 - Spring of the negative corrector; 18 - launcher; 19 - Coupling regulator; 20 - the body of the springs of the regulator; 21 - feed cut-off holes; Hinges of the knurling system of the regulator: M1 - the lever system at this point is maintained by two moving fingers installed in the lever 2; M4 - the overall axis of the levers of the launcher and the corrector; ΔS1 - the move of the dosing coupling.

After starting the engine of the controller, under the action of the centrifugal force, diverge and pushed the coupling of the regulator 19 to the right, overcoming the resistance of the spring supply spring 12. In this case, the head of the rod lever 16 rests on the point and in the power lever 10, and the M4 axis moves to the right on the joint Pores, until the force of the regulator's clutch is equal to an effort of a non-stroke spring 9. Accordingly, the dosing clutch 15 moves the m2 hinge to the left before setting the idle feed, which corresponds to the scheme in the figure.

Fig. Operation of the regulator at idle the minimum mode

The figure shows the interaction of the regulator elements when the diesel engine is operating on partial high-speed modes when the accelerator pedal is slightly pressed. The sequence with which the springs of the regulator comes into operation is determined by their rigidity and preliminary deformation. The first work of the damper spring 8 is running. It follows the spring of partial mode 6 and, finally, the spring of the nominal mode 5.

The control lever is connected to the accelerator pedal. When pressed on it, the damper spring 8 and the power lever is attracted to the left, as a result of which the dosing clutch moves to the right, towards an increase in the feed with an appropriate increase in the rotational speed. The coupling of the regulator 19 due to the increase in the centrifugal force of goods clicks on the lever of the corrector, which rests on. In the power lever at the point, with the result of which the idling spring is compressed as much as possible, and then the power lever is already two hinged points A and in the right to the right, along with the axis M2. Under these conditions, when the power lever is moving to the right, and the springs body under the action of the driver left, the spring load spring is compressed until the reaches of the balance of forces. When the load is reduced and increasing the speed of the power lever will move under the action of the coupling of the regulator 19 to the right to the course ΔS2 of the spring 6, and the dosing clutch 15 to the left, in the direction of decreasing the feed until the steady speed diesel mode is reached.

Fig. The operation of the regulator on the partial high-speed mode

Fig. Operation of the regulator at full load

The operation of the diesel regulator at full load is illustrated by the figure. In this case, the accelerator pedal is pressed until the control lever is stopped into the adjusting screw of the maximum mode. The power lever 10 at the same time turns out to be M3, and the start-up springs, the minimum idle 9, damper 8 and partial load 6 - in a fully compressed state. The coupling of the regulator 19 is in equilibrium under the action of the oppositely directed centrifugal force of cargo and the pre-tightening force of the working spring 5. Fuel supply on the full load mode is determined by the active plunger, indicated by two arrows at the dosing clutch 15. The two-mode regulator under consideration is equipped here with a negative fuel corrector. When the diesel engine is working on the left branch of the external high-speed characteristic, with N< nm пружина 17 отрицательного корректора разжимается и через систему рычагов перемещает дозирующую муфту 15 в сторону уменьшения подачи, отодвигая внешнюю характеристику от предела дымления.

Fig. The work of the negative corrector

The maximum idle speed mode and the formation of the corresponding regulatory characteristic take place when the engine load is reduced, operating on the full (nominal) power mode. In this case, the frequency of rotation of the engine and cargo of the regulator increases, and the latter move the coupling 19 to the right, which causes the spider of the regulator 5 to shrink and due to this rotates the system of the levers clockwise relative to the M2 axis, reducing the fuel supplusion to the idle feed value. This process is shown in the figure.

If full reset The load takes place an uncontrolled increase in the rotational speed, dangerous to the engine, the regulator completely stops the supply of fuel into the diesel cylinder. In this case, the operation of the regulator occurs in accordance with the figure, only at the speed of rotation is greater than on the maximum speed of the idle speed. At the same time, the dosing clutch is even more moved to the left, fully opening the cut-off holes 21, as a result of which all fuel from the high pressure chamber of the TNVD returns to the inner cavity of the pump housing and the fuel injection stops.

Fig. The operation of the regulator at idle the maximum mode

The graph of the high-speed characteristics of the fuel feeder considered above the two-mode regulator is shown in the figure, the purpose of various curves on the characteristic is designated by dying signatures. The presence of a springs of partial modes in the regulator allows you to obtain greater smoothness and control stability on the modes of small loads and rotational speeds. Otherwise, the characteristics of the two-fold regulator discussed above are similar to the overall characteristic.

Fig. High-speed characteristics of fuel feed pumps with a two-mode regulator: A - Starting feed, b - Section of reducing the feed after starting a diesel engine, V - Stroke when compressing the springs of partial mode, M is the driver control area of \u200b\u200bthe driver, D - regulatory characteristics of the maximum mode