Control device for plant and controlling method of the same

Patent metadata

Field	Value
Publication number	US-11835929-B2
Application number	US-202217675195-A
Country	US
Kind code	B2
Filing date	Feb 18, 2022
Priority date	Feb 26, 2021
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

Disclosed is a control device of a plant. The control device of a plant according to an embodiment includes a communication device configured to communicate with a plant; a processor configured to, based on receiving a command input for the plant, generate a control input for the plant and provide the control input to the plant, and the processor may calculate a feedforward control input of the plant using the command input and prestored first parameter, calculate an error based on a difference value of the command input and output of the plant, calculate a feedback control input of the plant using the calculated error and prestored second parameter, calculate a estimated disturbance of the plant based on the control input of the plant, output of the plant, and the prestored first parameter, generate the control input of the plant based on control input of the feedforward, control input of the feedback, and the estimated disturbance, and simultaneously adjust the first parameter and the second parameter based on an initial output of the plant during initial driving of the plant.

First claim

What is claimed is:

1. A control device of a plant comprising:
a communication device configured to communicate with the plant;
a processor configured to, based on receiving a command input for the plant, generate a control input for the plant and provide the control input to the plant,
wherein the processor is further configured to:
calculate a feedforward control input of the plant using the command input and prestored first parameter,
calculate an error based on a difference value of the command input and an output of the plant,
calculate a feedback control input of the plant using the calculated error and prestored second parameter,
calculate an estimated disturbance of the plant based on the control input of the plant, the output of the plant, and the prestored first parameter,
generate the control input of the plant based on the feedforward control input, the feedback control input, and the estimated disturbance, and
simultaneously adjust the first parameter and the second parameter based on an initial output of the plant during initial driving of the plant,
wherein the processor is further configured to use a cost function to update the first parameter and the second parameter to simultaneously adjust the first parameter and the second parameter,
wherein the cost function comprises an input weight to adjust a difference of magnitude of the control input and a value of the calculated error, and
wherein the cost function is defined based on a sum of 1) a product of a transpose of the value of the calculated error and the value of the calculated error, and 2) a value obtained by multiplying i) a product of a transpose of the control input and the control input by ii) the input weight that is obtained by dividing a magnitude of the value of the calculated error by a magnitude of the control input.

2. The device of claim 1 , wherein the first parameter comprises a first sub-parameter and a second sub-parameter, and
wherein the second parameter comprises a third sub-parameter and a fourth sub-parameter.

3. The device of claim 2 , wherein the first sub-parameter is related to inertia characteristics applied to the plant, and
wherein the second sub-parameter is related to friction characteristics applied to the plant.

4. The device of claim 2 , wherein the third sub-parameter is related to a proportional gain applied to the plant, and
wherein the fourth sub-parameter is related to a derivative gain applied to the plant.

5. The device of claim 1 , wherein the processor uses a nominal model of the plant and a Q-filter that is a low pass filter to calculate the estimated disturbance.

6. The device of claim 1 , wherein the processor is further configured to determine directionality of the first parameter and the second parameter using a Hessian matrix in setting a parameter update algorithm in the cost function.

7. A controlling method of a plant, the method comprising:
based on receiving a command input for the plant, calculating a feedforward control input of the plant using the command input and prestored first parameter;
calculating an error based on a difference value of the command input and an output of the plant;
calculating a feedback control input of the plant using the calculated error and prestored second parameter;
calculating an estimated disturbance of the plant based on a control input of the plant, the output of the plant, and the prestored first parameter;
generating the control input of the plant based on the feedforward control input, the feedback control input, and the estimated disturbance; and
simultaneously adjusting the first parameter and the second parameter based on an initial output of the plant during initial driving of the plant,
wherein the simultaneously adjusting the first parameter and the second parameter comprises using a cost function to update the first parameter and the second parameter to simultaneously adjust the first parameter and the second parameter,
wherein the cost function comprises an input weight to adjust a difference of magnitude of the control input and a value of the calculated error and
wherein the cost function is defined based on a sum of 1) a product of a transpose of the value of the calculated error and the value of the calculated error, and 2) a value obtained by multiplying i) a product of a transpose of the control input and the control input by ii) the input weight that is obtained by dividing a magnitude of the value of the calculated error by a magnitude of the control input.

8. The method of claim 7 , wherein the calculating the estimated disturbance comprises using a nominal model of the plant and a Q-filter that is a low pass filter to calculate the estimated disturbance.

9. The method of claim 7 , wherein the simultaneously adjusting the first parameter and the second parameter comprises determining directionality of the first parameter and the second parameter using a Hessian matrix in setting a parameter update algorithm in the cost function.

10. The method of claim 7 , wherein the first parameter comprises a first sub-parameter and a second sub-parameter, and
wherein the second parameter comprises a third sub-parameter and a fourth sub-parameter.

11. The method of claim 10 , wherein the first sub-parameter is related to inertia characteristics applied to the plant, and
wherein the second sub-parameter is related to friction characteristics applied to the plant.

12. The method of claim 11 , wherein the third sub-parameter is related to a proportional gain applied to the plant, and
wherein the fourth sub-parameter is related to a derivative gain applied to the plant.

Assignees

• Daegu Gyeongbuk Inst Science & Tech

Inventors

• Oh Sehoon
• Jung Hanul

Classifications

• G05B13/042 Primary

  in which a parameter or coefficient is automatically adjusted to optimise the performance · CPC title

• G05B6/02

  electric · CPC title

• G05B13/04 Primary

  involving the use of models or simulators · CPC title

• G05B13/02 Primary

  electric · CPC title

• G05B11/42

  for obtaining a characteristic which is both proportional and time-dependent, e.g. P. I., P. I. D. · CPC title