Generic PID design and tuning
AssigneeCleveland State University
InventorsZhiqiang Gao, Yu Hu
Life of this patent
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Abstract
An industrial controller implements a closed-loop control technique referred to as generic PID control, or GPID, which makes explicit the basic principles and methods of quantitatively combining the past, present and future in controller design and tuning. Generic PID control is backward compatible in design and in tuning with current industrial control software interfaces, and as such can be easily adopted onto existing control systems. Generic PID is also widely applicable to artificial intelligence (AI) and data analytics, such as machine learning, where error-correction is core to all algorithms.
Claims20
An industrial controller, comprising:
- a memory;
- and
- a processor configured to execute components stored on the memory, the components comprising:
- a program execution component configured to execute an industrial control program that sets a reference value r of a system variable of a plant;
- and
- a generic proportional-integral-derivative (GPID) control component configured to set a value of a control signal u that controls the system variable based on an error signal e representing a difference between the reference value r and a measured value y of the system variable,
- wherein the GPID control component sets the control signal u as a sum of a first output of a cascade lead compensator with a first lowpass filter that processes the error signal e, a second output of an nth order differentiator with a second lowpass filter that processes the error signal e, and a third output of a third lowpass filter applied to the control signal u, where n is an integer.
A method, comprising:
- setting, by a system comprising a processor, a reference value r of a system variable of a plant;
- and
- setting, by the system, a value of a control signal u that controls the system variable based on an error signal e representing a difference between the reference value r and a measured value y of the system variable,
- wherein the setting of the value of the control signal u comprises setting the value of the control signal u as a sum of a first output of a cascade lead compensator with a first lowpass filter that processes the error signal e, a second output of an nth order differentiator with a second lowpass filter that processes the error signal e, and a third output of a third lowpass filter applied to the control signal u, where n is an integer.
A non-transitory computer-readable medium having stored thereon executable components that, in response to execution by a system comprising a processor, cause the system to perform operations, the operations comprising:
- setting a reference value r of a system variable of a plant;
- and
- setting a value of a control signal u that controls the system variable based on an error signal e representing a difference between the reference value r and a measured value y of the system variable, wherein the setting of the value of the control signal u comprises:
- processing the error signal e with a cascade lead compensator having a first lowpass filter to yield an output u0;
- processing the error signal e with an nth order differentiator having a second lowpass filter to yield an output u1;
- processing the control signal u with a third lowpass filter to yield an output u2;
- and
- setting the value of the control signal u based on a sum of u0, u1, and u2.
Dependencies are inferred from the claim text.