Plasma processing control system with adaptive fuzzy controller
Fuzzy control systems and methods are disclosed. A method includes receiving a reference signal defining target values for a parameter that is controlled at an output of the plasma processing system and obtaining a measure of the parameter that is controlled at the output. A fuzzy controller provides a control signal to adjust at least one actuator based at least upon the reference signal and the measure of the controlled parameter. In addition, output membership functions of the fuzzy controller, input membership functions of the fuzzy controller, and a rule base of the fuzzy controller are adapted while controlling an output of a system based at least upon the based at least upon an estimated model parameter tensor, the reference signal and the measure of the controlled parameter, and the control signal.
1. A plasma processing control system comprising: a user interface configured to receive a reference signal defining target values for a controlled parameter that is provided to a controlled output of a plasma processing system;
at least one sensor to obtain a measure of the controlled parameter that is controlled at the controlled output of the plasma processing system;
an estimation law module configured to produce an estimated model parameter tensor, θ;
a fuzzy controller configured to provide a control signal to adjust at least one actuator, that controls the controlled output of the plasma processing system, based at least upon the reference signal and the measure of the controlled parameter;
a dynamic modification module configured to provide an estimate of the controlled parameter, and while the controlled parameter is being controlled, the dynamic modification module is configured, based at least upon the reference signal, the estimate of the controlled parameter, the measure of the controlled parameter, and the control signal to:
adapt output membership functions of the fuzzy controller;
adapt input membership functions of the fuzzy controller; and
adapt a rule base of the fuzzy controller.
2. The control system of claim 1 wherein the output membership functions, the input membership function and the rule base are adapted simultaneously.
3. The control system of claim 1 wherein the output membership functions, the input membership function and the rule base are not adapted simultaneously.
4. The system of claim 1 , wherein the controlled output is an output coupled to a plasma processing chamber.
5. The system of claim 1 , wherein the controlled output is an output of an actuator within the plasma processing system.
6. The system of claim 1 , wherein the user interface is configured to at least one of enable an operator of the plasma processing system to set the target values and enable a controller to set the target values.
7. The system of claim 1 , wherein the at least one actuator comprises a DC section configured to apply a DC rail voltage to a power amplifier.
8. The system of claim 1 , wherein the parameter that is controlled is one of forward power, reflected power, or reflection coefficient.
9. A method for controlling a plasma processing system comprising:
receiving a reference signal defining target values for a parameter that is controlled at an output of the plasma processing system;
obtaining, by a sensor, a measure of the parameter that is controlled at the output;
producing an estimated model parameter tensor, θ;
producing an estimate of the controlled parameter;
using a fuzzy controller to provide a control signal to adjust at least one actuator, that controls the output of the plasma processing system, based at least upon the reference signal and the measure of the controlled parameter;
adapting output membership functions of the fuzzy controller, input membership functions of the fuzzy controller, and a rule base of the fuzzy controller, based at least upon the estimated model parameter tensor, θ, the reference signal, the estimate of the controlled parameter, the measure of the controlled parameter, and the control signal, while controlling the controlled parameter.
10. The method of claim 9 , wherein the output is an output coupled to a plasma processing chamber.
11. The method of claim 9 , wherein adjusting the at least one actuator comprises adjusting a DC section configured to apply a DC rail voltage to a power amplifier.
12. The method of claim 9 , wherein the parameter that is controlled is one of forward power, reflected power, or reflection coefficient.
13. The method of claim 9 , wherein the output is an actuator output of the at least one actuator.
14. The method of claim 9 , wherein the dynamic modification module is configured to store updates to the rule base and expand the rule base through tensorial correction values, zooming and sliding tensorial memory grids, or at least one of delay, filtering, and averaging operators.
15. A non-transitory medium encoded with instructions that are executable by a processor and/or used to program a field programmable gate array, the instructions including instructions to:
receive a reference signal defining target values for a parameter that is controlled at an output of a plasma processing system;
obtain, by a sensor, a measure of the parameter that is controlled at the output;
produce an estimated model parameter tensor, θ;
produce an estimate of the controlled parameter;
use a fuzzy controller to provide a control signal to adjust at least one actuator, that controls the output of the plasma processing system, based at least upon the reference signal and the measure of the controlled parameter;
adapt output membership functions of the fuzzy controller, input membership functions of the fuzzy controller, and a rule base of the fuzzy controller, based at least upon the estimated model parameter tensor, θ, the reference signal, the estimate of the controlled parameter, the measure of the controlled parameter, and the control signal, while controlling the controlled parameter.
16. The non-transitory medium of claim 15 , wherein the instructions comprise instructions to provide the control signal to an output coupled to a plasma processing chamber.
17. The non-transitory medium of claim 15 , wherein the instructions to adjust the at least one actuator comprise instructions to adjust a DC section configured to apply a DC rail voltage to a power amplifier.
18. The non-transitory medium of claim 15 , wherein the parameter that is controlled is one of forward power, reflected power, or reflection coefficient.
19. The non-transitory medium of claim 15 , wherein the output is an actuator output of the at least one actuator.
20. The non-transitory medium of claim 15 , further configured to store updates to the rule base and expand the rule base through tensorial correction values, zooming and sliding tensorial memory grids, or at least one of delay, filtering, and averaging operators.