DE102019134917A1 - Method for improving the control of an actuator and device for carrying out the method - Google Patents

Abstract

A method for improving the control of a controlled system with at least one actuator, comprising the steps of: a) determining and setting a target value to be achieved for a controlled variable of the actuator; b) determining a precontrol of a manipulated variable of the actuator by means of a precontrol signal of a manipulated variable consisting of a static Pre-control of the manipulated variable by means of a static pre-control signal and a dynamic pre-control of the manipulated variable by means of a dynamic pre-control signal, as well as feedback control of the actuator by means of a feedback signal of the manipulated variable; c) generating a combined control signal by combining the precontrol signal of the manipulated variable and the feedback signal the manipulated variable and control of the actuator by means of the combined control signal; d) measuring the actual value of the controlled variable of the actuator after control of the actuator by means of the combined control signal; e) feeding the precontrol signal back into a system model and Generation of a controlled variable of the system model and formation of a first system deviation value between the target value to be achieved of the controlled variable and the controlled variable of the system model and feedback of the first system deviation value into the dynamic feedforward control of the manipulated variable, and formation of a second system deviation value between the controlled variable of the system model and the actual Value of the controlled variable after activation and feedback of the second control difference value in the feedback control of the manipulated variable.

Description

The invention relates to a method for improving the control of a controlled system, which preferably comprises at least one actuator in order to change a measured variable belonging to the controlled system, as well as a device for carrying out such a method.

This procedure aims to follow up a change in the measured variable of the controlled system more quickly and reliably and to set an actual value to be achieved for the controlled system.

Methods are known from the prior art by means of which a pre-control of the controlled system and also a feedback control are carried out in order to adapt a controlled system from a current value to the actual value of the measured variable to be achieved. A feedforward control and a feedback control are known from the prior art and are often used in a combined manner.

However, such methods or systems from the prior art have disadvantages which turn out to be disadvantageous in the real system. A lack of coordination between the feedforward control and the feedback control can lead to overshoots occurring.

It is accordingly the object of the present invention to provide a method and a device for carrying out the method, as a result of which control of the controlled system can be improved.

This object is achieved by the subject matter having the features of claim 1 and claim 5.

1. a) Bestimmen und Setzen eines zu erreichenden Soll-Werts der Regelgröße der Regelstrecke;
2. b) Bestimmen einer Vorsteuerung der Regelstrecke mittels eines Vorsteuersignals einer Stellgröße bestehend aus einer statischen Vorsteuerung der Stellgröße mittels eines statischen Vorsteuersignals und einer dynamischen Vorsteuerung der Stellgröße mittels eines dynamischen Vorsteuersignals, sowie einer Feedback-Steuerung der Regelstrecke mittels eines Feedback-Signals der Stellgröße;
3. c) Erzeugen eines kombinierten Steuersignals durch Kombinieren des Vorsteuersignals der Stellgröße und des Feedback-Signals der Stellgröße und Ansteuern des Aktuators mittels des kombinierten Steuersignals;
4. d) Messen des Ist-Werts der Regelgröße der Regelstrecke nach Ansteuerung der Regelstrecke mittels des kombinierten Steuersignals;
5. e) Rückführen des Vorsteuersignals in ein Streckenmodell und Erzeugen einer Regelgröße des Streckenmodells und Bilden eines ersten Differenzwerts zwischen dem zu erreichenden Ist-Wert der Regelgröße und der Regelgröße des Streckenmodells und Rückführen des ersten Differenzwerts in die dynamische Vorsteuerung der Regelgröße, und Bilden eines zweiten Differenzwerts zwischen der Regelgröße des Streckenmodells und dem Ist-Wert der Regelgröße nach Ansteuerung und Rückführen des zweiten Differenzwerts in die Feedback-Steuerung der Stellgröße.

The core idea of the invention is to provide a method for improving the control of a controlled system, which preferably has an actuator in order to change a controlled variable belonging to the controlled system, comprising the method steps:

1. a) determining and setting a target value to be achieved for the controlled variable of the controlled system;
2. b) determining a pre-control of the controlled system by means of a pilot signal of a manipulated variable consisting of a static pilot control of the manipulated variable by means of a static pilot signal and a dynamic pilot control of the manipulated variable by means of a dynamic pilot signal, as well as a feedback control of the controlled system by means of a feedback signal of the manipulated variable;
3. c) generating a combined control signal by combining the pilot signal of the manipulated variable and the feedback signal of the manipulated variable and controlling the actuator by means of the combined control signal;
4. d) measuring the actual value of the controlled variable of the controlled system after activation of the controlled system by means of the combined control signal;
5. e) Feeding the precontrol signal back into a plant model and generating a controlled variable of the plant model and forming a first difference value between the actual value to be achieved of the controlled variable and the controlled variable of the plant model and feeding back the first differential value into the dynamic precontrol of the controlled variable, and forming a second differential value between the controlled variable of the plant model and the actual value of the controlled variable after activation and feedback of the second differential value into the feedback control of the manipulated variable.

A controlled variable is to be understood as the variable which is or is to be controlled by the controlled system. In particular, the controlled system comprises one or more actuators by means of which the controlled variable can be controlled.

The controlled system is that part of the control loop that includes the physical variable to be controlled, that is, the controlled variable, which is to be acted on by means of the manipulated variable.

The controlled variable is in particular an essentially constant value, based on a period of time which is short enough for this. Adjustments to the system may make it necessary to change the value of the controlled variable. A corresponding target value for the controlled variable is determined and set according to the requirements of the system. The setpoint value can preferably be above or below the actual value of the controlled variable.

After the setpoint value of the controlled variable is known, a pre-control, also known as a feedforward control, is carried out on the controlled system. According to the invention, the precontrol includes a static precontrol of the manipulated variable of the controlled system and a dynamic precontrol of the manipulated variable of the controlled system and, in turn, feedback control of the manipulated variable of the controlled system. The manipulated variable of the controlled system is the variable by means of which the controlled system is controlled in order to change the controlled variable. This means that a pre-control of the controlled system is determined by means of a pilot control signal of a manipulated variable, the pilot control consisting of a static pilot control of the manipulated variable by means of a static pilot control signal and a dynamic pilot control of the manipulated variable by means of a dynamic pilot control signal, as well as a feedback control of the controlled system by means of a feedback signal of the manipulated variable.

After these pre-controls and the feedback control have been determined, they are combined with one another to form a combined control signal by means of which the controlled system or the actuator is controlled.

Then, after the controlled system has been activated, an actual value of the controlled variable is determined.

The precontrol signal is then fed back into a plant model and a controlled variable of the plant model is generated and a first control difference value between the target value to be achieved for the controlled variable and the controlled variable of the plant model and the first control difference value is fed back into the dynamic feedforward control of the manipulated variable, and a second control difference value is formed between the controlled variable of the plant model and the actual value of the controlled variable after activation and feedback of the second control difference value in the feedback control of the manipulated variable.

According to the invention, the controlled variable of the system model is only dependent on the pilot control signal, that is, the static and dynamic pilot control of the manipulated variable.

The system model is preferably stored in a storage unit or a memory, and is predetermined and can be changed later. The system model is used to predict the behavior of the system or the controlled system or the actuator when the system or the controlled system or the actuator is activated.

In this context, a system model is understood in particular to mean that the actual controlled system is modeled, that is, is represented theoretically, and a modeled output variable can be generated in accordance with the input variables. The plant model is represented using a set of differential equations. The system model can be designed to be as extensive as desired and include the most varied of relationships of the controlled system. In particular, the dynamics of the system are mapped, as well as the time behavior of the system.

In the following, the functionality of the different controls of the controlled system or the actuator is shown in more detail.

A static pilot control is understood as in the prior art. A value is applied to the manipulated variable of the controlled system or the actuator.

The dynamic pre-control in the sense of the registration serves in particular to regulate the system model to the target value of the controlled variable to be achieved quickly and in a timed or coordinated manner. In a mathematical sense, this means that: $$\left(\text{target to be achieved}-\text{Value of the controlled variable}\right)-\left(\text{Controlled variable of the plant model}\right)\to 0$$

The feedback control, on the other hand, is intended to adapt the (measured) actual value of the controlled variable to the controlled variable of the system model, i.e.: $$\left(\text{Controlled variable of the plant model}\right)-\left(\text{Is}-\text{Value of the controlled variable}\right)\to 0$$

In addition, the feedback control corrects deviations in the steady state, in particular in the route model.

According to a particularly preferred embodiment, the pilot control signal of the manipulated variable, in particular the static pilot control signal, is dependent on one or more disturbance variables. Disturbance variables are to be understood as in the prior art, namely that they influence the regulation of the system or of the actuator.

Depending on the disturbance variable or variables, other feedforward control signals are of course necessary, since not only must the controlled variable be changed, but the influence of the disturbance variables must also be overcome.

According to a further preferred embodiment, the feeding back of the pilot control signal comprises the formation of a difference value between the combined control signal and the feedback signal.

This means that the combined control signal of the manipulated variable, by which the controlled system or the actuator is controlled, is initially fed back, but only the pilot control signal is fed back to the system model through the just described difference value formation. This is advantageous because, according to the invention, only the controlled variable of the system model is necessary in order to optimize the precontrol of the actuator. In addition, the system can also be prevented from adding up, since the feedback control signal is not used again for feedback control by means of the feedforward control; in particular, the integral component of the feedback signal is adapted by subtracting the feedback signal, so that further integration of the integral component can be avoided if the manipulated variable is limited. This can also be referred to as "anti-windup".

According to a further preferred embodiment, the combined control signal is compared with a limited combined control signal, the combined control signal being reduced when the limited combined control signal is exceeded so that the combined control signal no longer exceeds the limited combined control signal and does not exceed a predetermined proportion of the value of the has limited combined control signal.

This is advantageous in that by determining and setting the desired value to be achieved, a manipulated variable could be necessary which the controlled system could not handle or cannot provide, and which could possibly damage the controlled system.

This describes a limitation of the control signal of the manipulated variable of the controlled system, which primarily serves to protect the controlled system.

According to a further preferred embodiment, it is conceivable that the dynamic precontrol is in communication-related connection with the system model and / or the static precontrol. Communication connection means that the dynamic pilot control has access to the stored data of the plant model and also has access to the data of the pilot control, in particular to the value that is to be applied to the actual value of the controlled variable in order to generate a suitable dynamic pilot control signal to be able to create.

schneller erreicht werden kann, da bereits vor der Erzeugung des ersten Differenzwerts zwischen dem zu erreichenden Soll-Wert der Regelgröße und der Regelgröße des Streckenmodells eine Optimierung stattgefunden hat.As a result, it is possible and conceivable that the condition $$\left(\text{target to be achieved}-\text{Value of the controlled variable}\right)-\left(\text{Controlled variable of the plant model}\right)\to 0$$

can be achieved more quickly, since an optimization has already taken place before the generation of the first difference value between the desired value of the controlled variable to be achieved and the controlled variable of the system model.

• mindestens einen Sensor zum Messen eines Ist-Werts der Regelgröße,
• eine Speichereinheit, in welcher das Streckenmodell hinterlegt ist,
• eine Recheneinheit zum Erzeugen des kombinierten Steuersignal, des ersten Regeldifferenzwerts und des zweiten Differenzwerts,
• eine Ansteuereinheit zum Ansteuern der Regelstrecke, bevorzugt umfassend den Aktuator, mittels des kombinierten Steuersignals.

Furthermore, the underlying object is achieved by a device for performing the method according to the invention, comprising:

• at least one sensor for measuring an actual value of the controlled variable,
• a storage unit in which the route model is stored,
• a computing unit for generating the combined control signal, the first control difference value and the second difference value,
• a control unit for controlling the controlled system, preferably comprising the actuator, by means of the combined control signal.

It is also conceivable that a static pilot control unit is provided for the static pilot control, a dynamic pilot control unit for the dynamic pilot control and a feedback control unit for the feedback control in order to be able to generate the corresponding control signals. Each unit is also designed with corresponding input channels and output channels for receiving and transmitting the respective associated signals.

It is also conceivable that the control unit limits the combined control signal.

Further advantageous embodiments emerge from the subclaims.

• 1 Verfahren gemäß Stand der Technik;
• 2A, 2B Verlauf Regelgrößen und Stellgrößen gemäß Verfahren nach 1;
• 3 Verfahren gemäß einer bevorzugten Ausführungsform;
• 4A Verfahren gemäß einer weitergehenden Ausführungsform;
• 4B Verfahren gemäß einer weitergehenden Ausführungsform;
• 5A, 5B Verlauf Regelgrößen und Stellgrößen gemäß Verfahren nach 4A oder 4B;
• 6 Verlauf der Regelgrößen und Stellgrößen eines erfindungsgemäßen Verfahrens im Vergleich mit dem Stand der Technik;
• 7 Vorrichtung zum Durchführen des Verfahrens nach 3, 4A und 4B.

Further objects, advantages and expediencies of the present invention can be taken from the following description in conjunction with the drawing. Here show:

• 1 Prior art method;
• 2A , 2 B Course of controlled variables and manipulated variables according to the procedure 1 ;
• 3 Method according to a preferred embodiment;
• 4A Method according to a further embodiment;
• 4B Method according to a further embodiment;
• 5A , 5B Course of controlled variables and manipulated variables according to the procedure 4A or 4B ;
• 6th Course of the controlled variables and manipulated variables of a method according to the invention in comparison with the prior art;
• 7th Device for performing the method according to 3 , 4A and 4B .

d

Störgröße

y

Regelgröße

u

Stellgröße

e

Regeldifferenz bzw. Differenzwert

Control-related abbreviations were used in the figures, namely:

d

Disturbance

y

Controlled variable

u

Manipulated variable

e

Control difference or difference value

Reference numbers have also been assigned to the respective parts of the figures, so that some parts have both an abbreviation in the above sense and a reference number.

In the 1 an overview of the state of the art is given, with the relevant structures and process steps being displayed.

In the 2A is an overview of the controlled variable and in the 2 B an overview of the manipulated variable of the controlled system 1 specified. The controlled system 1 includes at least one actuator 1' .

Like in the 1 can be seen, a target value to be achieved y _Sp ; 12th the controlled variable determines and sets which one is to be achieved. In order to achieve the target value y _Sp ; 12th to achieve, the target value y _Sp ; 12th to a static pilot control unit 2 transmitted, by means of which, taking into account disturbance variables d; 13th a static pilot control signal uSFf; 8th the manipulated variable of the actuator 1 is produced.

The static pre-control signal uSFf; 8th is with a feedback control signal uFb; 10 combined into a combined control signal u; 11 , by means of which the controlled system 1 or the actuator 1' , in particular by means of a control unit 15th , is controlled.

By means of a measuring device 16 comprising at least one sensor 17th becomes the actual value y; 18th the controlled variable measured and between the target value to be achieved y _Sp ; 12th and the actual value y; 18th a difference value is formed in the prior art and sent to a feedback control unit 3 which the feedback control signal uFb; 10 generated, returned.

By forming the difference value e; 14th in the prior art, the deviation of the actual value y; 18th to the target value to be achieved y _Sp ; 12th shown. By adapting the feedback Control signal uFb; 10 by means of the feedback control unit 3 can this difference between the actual value y; 18th and target value y _Sp ; 12th be balanced.

In the 2A the development of the controlled variable is shown, where y _Sp ; 12th represents the target value of the controlled variable. The curve ySFf represents the curve of how the controlled variable changes if only a static feedforward control is carried out. The curve yFb shows how the controlled variable changes if only feedback control is carried out. Curve y is the curve of the measured controlled variable.

In comparison, the 2 B the curve of the manipulated variable of the actuator 1' , the curve uSFf representing the curve of the static feedforward control if only a static feedforward control is carried out. The curve u shows the entire manipulated variable over time. As can be seen, a disproportionate increase can be seen when setting the target value of the controlled variable. Such increases should be avoided if possible.

The 3 shows a method according to the invention in accordance with a preferred embodiment.

1. a) Bestimmen und Setzen eines zu erreichenden Soll-Werts y_Sp; 12 der Regelgröße des Aktuators 1';
2. b) Bestimmen einer Vorsteuerung des Aktuators 1' mittels eines Vorsteuersignals uFf: 19 einer Stellgröße bestehend aus einer statischen Vorsteuerung der Stellgröße mittels eines statischen Vorsteuersignals uSFf; 8 und einer dynamischen Vorsteuerung der Stellgröße mittels eines dynamischen Vorsteuersignals uDFf; 9, sowie einer Feedback-Regelung des Aktuators 1' mittels eines Feedback-Signals uFb; 10 der Stellgröße;
3. c) Erzeugen eines kombinierten Steuersignals u; 11 durch Kombinieren des Vorsteuersignals uFf; 19 der Stellgröße und des Feedback-Signals uFb; 10 der Stellgröße und Ansteuern des Aktuators 1' mittels des kombinierten Steuersignals u; 11;
4. d) Messen des Ist-Werts y; 18 der Regelgröße des Aktuators 1' nach Ansteuerung des Aktuators 1 mittels des kombinierten Steuersignals u; 11;
5. e) Rückführen des Vorsteuersignals uFf; 19 in ein Streckenmodell 5 und Erzeugen einer Regelgröße yFf; 21 des Streckenmodells 5 und Bilden eines ersten Differenzwerts eFf; 6 zwischen dem zu erreichenden Soll-Wert y_Sp; 12 der Regelgröße und der Regelgröße yFf; 21 des Streckenmodells 5 und Rückführen des ersten Differenzwerts eFf; 6 in die dynamische Vorsteuerung 4 der Regelgröße, und Bilden eines zweiten Differenzwerts e; 7 zwischen der Regelgröße yFf; 21 des Streckenmodells 5 und dem Ist-Wert y; 18 der Regelgröße nach Ansteuerung und Rückführen des zweiten Differenzwerts e; 7 in die Feedback-Steuerung 3 der Stellgröße.

The method shown for improving the control of an actuator 1 In order to change a controlled variable y belonging to the actuator, the process steps include:

1. a) determining and setting a target value y _{Sp to be achieved} ; 12th the controlled variable of the actuator 1' ;
2. b) Determining a pilot control of the actuator 1' by means of a pre-control signal uFf: 19th a manipulated variable consisting of a static precontrol of the manipulated variable by means of a static precontrol signal uSFf; 8th and dynamic precontrol of the manipulated variable by means of a dynamic precontrol signal uDFf; 9, as well as a feedback control of the actuator 1' by means of a feedback signal uFb; 10 the manipulated variable;
3. c) generating a combined control signal u; 11 by combining the pilot control signal uFf; 19th the manipulated variable and the feedback signal uFb; 10 the manipulated variable and control of the actuator 1' by means of the combined control signal u; 11 ;
4. d) measuring the actual value y; 18th the controlled variable of the actuator 1' after activation of the actuator 1 by means of the combined control signal u; 11 ;
5. e) feeding back the pilot control signal uFf; 19th into a plant model 5 and generating a controlled variable yFf; 21 of the route model 5 and forming a first difference value eFf; 6th between the target value to be achieved y _Sp ; 12th the controlled variable and the controlled variable yFf; 21 of the route model 5 and feeding back the first difference value eFf; 6th into the dynamic feedforward control 4th the controlled variable, and forming a second difference value e; 7th between the controlled variable yFf; 21 of the route model 5 and the actual value y; 18th the controlled variable after activation and feedback of the second difference value e; 7th into the feedback control 3 the manipulated variable.

The arrows shown here show the course, with the setting of the target value being the starting point of the method.

After the target value y _Sp ; 12th the controlled variable is known, a pre-control, also known as feedforward control, of the actuator 1' carried out. According to the invention, the pilot control comprises a static pilot control 2 the manipulated variable of the actuator 1' and a dynamic feedforward control 3 the manipulated variable of the actuator 1' and again a feedback control of the manipulated variable of the actuator 1' . The manipulated variable of the actuator 1' is the size by which the actuator 1' is controlled in order to change the controlled variable. This means that a determination of a precontrol of the actuator 1' by means of a pilot control signal uFf; 19th a manipulated variable is carried out, the pre-control from a static pilot control of the manipulated variable by means of a static pilot control signal and a dynamic pilot control of the manipulated variable by means of a dynamic pilot control signal, as well as a feedback control of the actuator 1' by means of a feedback signal of the manipulated variable.

After these pre-controls and the feedback control have been determined, they are combined with one another to form a combined control signal u; 11 , by means of which the actuator 1' is controlled.

Then after the actuator 1' has been activated, an actual value y; 18th determined by the controlled variable.

Then the pilot control signal uFf; 19th into the plant model 5 fed back and a controlled variable yFf; 21 of the route model 5 generated and a first difference value eFf; 6th between the target value to be achieved y _Sp ; 12th the controlled variable and the controlled variable yFf; 21 of the route model 5 and feeding back the first difference value eFf; 6th into the dynamic feedforward control 4th the manipulated variable, and forming a second difference value e; 7th between the controlled variable of the plant model 5 and the actual value y; 18th the controlled variable after activation and feedback of the second difference value e; 7th into the feedback scheme 4th the manipulated variable.

According to the invention, the controlled variable of the system model is only dependent on the pilot control signal, that is, the static and dynamic pilot control of the manipulated variable.

It can also be seen that the control, in particular the precontrol, and the controlled system 1 depending on disturbance variables d; 13th are, which can be known and unknown disturbance variables. Also the route model 5 depends on the disturbance variables 13th .

It can also be seen that the plant model 5 in signaling connection with the dynamic control of the plant model 5 ' that means that the dynamic control is based on data from the plant model 5 can access.

In the 4A or the 4B FIG. 13 is a further embodiment based on the embodiment according to FIG 3 shown, the further embodiment being described in more detail below.

Next, the combined control signal u; 11 compared with a limited combined control signal, wherein when the limited combined control signal is exceeded, the combined control signal u; 11 is reduced so that the combined control signal no longer exceeds the limited combined control signal and has at most a predetermined proportion of the value of the limited combined control signal. This is then called uLim; 20th designated. This has the advantage that when the combined control signal u; 11 would be dimensioned in such a way that the controlled system 1 or the actuator 1' this combined signal u; 11 could not process, the combined control signal u; 11 limited and as a limited combined control signal uLim; 20th continued.

The circuit of the 4B differs from the circuit of the 4A , but serves the same purpose and works identically to the circuit of the 4A .

The 5A and 5B show in a manner analogous to the 2A and 2 B the curves of the controlled variables and the manipulated variables.

5A shows the different curves of the controlled variable, 5B the curves of the manipulated variable of the actuator 1' .

As can be clearly seen, the difference between the value of the controlled variable yFf; 21 and the actual value y; 18th already very low, that is, an adaptation of the controlled variable by means of the feedback control has already been carried out very well. This can also be good from the 4B can be recognized because the curve uFb; 10 shows only small changes in value.

Next in the 5B it can be seen that the curve uLim; 20th would exceed a limit value and is therefore limited, represented by a plateau of the curve. A limitation was necessary here because a manipulated variable requirement was placed on the actuator 1 which it would not have been able to process within the normal parameters.

In the 6th is shown again how the course of the actual variable y; 18th the controlled system 1 runs, depending on the time. The different parts, static pilot control, dynamic pilot control and feedback control, are each shown as a graph. As can be seen, only the combination of static feedforward control, dynamic feedforward control and feedback control is sufficiently fast and that combination which can achieve the setpoint value of the controlled variable in the respective time window.

• eine Messeinrichtung 16 mit mindestens einem Sensor 17 zum Messen eines Ist-Werts einer Regelgröße,
• eine Speichereinheit 23, in welcher das Streckenmodell hinterlegt ist,
• eine Recheneinheit 22 zum Erzeugen des kombinierten Steuersignal, des ersten Differenzwerts und des zweiten Differenzwerts,
• eine Ansteuereinheit 15 zum Ansteuern eines Aktuators 1' der Vorrichtung mittels des kombinierten Steuersignals,
• eine statische Vorsteuereinheit 2,
• eine dynamische Vorsteuereinheit 4,
• eine Feedback-Regeleinheit 3, und
• eine Regelstrecke 1, bevorzugt umfassend einen Aktuator 1.

The 7th a device according to an embodiment for performing a method according to the invention is shown, the device comprising:

• a measuring device 16 with at least one sensor 17th for measuring an actual value of a controlled variable,
• a storage unit 23 in which the plant model is stored,
• an arithmetic unit 22nd for generating the combined control signal, the first difference value and the second difference value,
• a control unit 15th to control an actuator 1' the device by means of the combined control signal,
• a static pilot control unit 2 ,
• a dynamic pilot control unit 4th ,
• a feedback control unit 3 , and
• a controlled system 1 , preferably comprising an actuator 1 .

The relationships of the respective elements are in the 5 and relate to communication between these elements, shown by dashed lines.

All features disclosed in the application documents are claimed as essential to the invention, provided that they are new to the state of the art, individually or in combination.

List of reference symbols

1

Controlled system

1'

Actuator

2

static pilot control unit

3

Feedback control unit

4th

dynamic pilot control unit

5

Plant model

5 '

dynamic control unit of the plant model

6th

first difference value

7th

second difference value

8th

static pilot signal

9

dynamic pre-control signal

10

Feedback control signal

11

combined control signal

12th

Target value to be achieved for the controlled variable

13th

Disturbance

14th

System deviation value in the prior art

15th

Control unit

16

Measuring unit

17th

sensor

18th

Actual value of the controlled variable

19th

Pilot signal

20th

limited combined control signal

21

Controlled variable of the plant model

22nd

Arithmetic unit

23

Storage unit

Claims (5)

Method for improving the control of a controlled system (1) with at least one actuator (2) in order to change a controlled variable belonging to the actuator (2), comprising the method steps: a) determining and setting a target value (12) to be achieved of a controlled variable of the actuator (2); b) determining a precontrol of a manipulated variable of the actuator (2) by means of a precontrol signal (19) of a manipulated variable consisting of a static precontrol of the manipulated variable using a static precontrol signal (8) and a dynamic precontrol of the manipulated variable using a dynamic precontrol signal (9), as well as a Feedback control of the actuator (2) by means of a feedback signal (10) of the manipulated variable; c) generating a combined control signal (11) by combining the pilot signal (19) of the manipulated variable and the feedback signal of the manipulated variable and controlling the actuator (2) by means of the combined control signal (11); d) measuring the actual value of the controlled variable (18) of the actuator (2) after activation of the actuator (2) by means of the combined control signal (11); e) Feeding the pilot control signal (19) back into a system model (5) and generating a controlled variable (21) of the system model (5) and forming a first control difference value between the target value (12) to be achieved of the controlled variable and the controlled variable (21) of the Plant model (5) and feeding back the first control difference value into the dynamic precontrol of the manipulated variable, and forming a second control difference value between the controlled variable (21) of the plant model (5) and the actual value of the controlled variable (18) after the control and feeding back of the second control difference value in the feedback control of the manipulated variable. Procedure according to Claim 1 , characterized in that the pilot signal (19) of the manipulated variable is dependent on one or more disturbance variables (13). Method according to one of the Claims 1 to 2 , characterized in that the combined control signal (11) is compared with a limited combined control signal (20), the combined control signal (11) being reduced if the limited combined control signal (20) is exceeded, so that the combined control signal (11 ) no longer exceeds the limited combined control signal (20) and has at most a predetermined proportion of the value of the limited combined control signal (20). Procedure according to Claim 3 , characterized in that the feeding back of the precontrol signal comprises the formation of a difference value between the combined control signal and the feedback signal. Device for performing the method according to one of the Claims 1 to 4th , comprising: at least one actuator (2); at least one sensor (17) for measuring an actual value of a controlled variable (18), a storage unit in which the system model (5) is stored, a computing unit (22) for generating the combined control signal (11), the first control difference value (6 ) and the second control difference value (7), a control unit (15) for controlling the actuator (2) of the device by means of the combined control signal (11).

Images