A Two-speed Adaptive Proportional-Derivative Control Method

Abstract

Aiming at the control problems of non-affine nonlinear uncertain systems, a Two-Speed ​​Adaptive Proportional-Derivative (2SAPD) control method that does not depend on the plant model is invented. The control method of the invention defines the system dynamics and internal and external uncertainties as the sum disturbance, thereby transforming the non-affine nonlinear uncertain system into a linear uncertain system, and then constructs the error dynamic system under the excitation of the sum disturbance, according to which A two-speed adaptive proportional-derivative controller model with center speed factor as the core is designed. Theoretical analysis shows that the closed-loop control system composed of 2SAPD controller not only has global asymptotically stable robustness, but also has good anti-disturbance robustness. The invention has wide application value in the fields of electric power, machinery, chemical industry, transportation, aviation, aerospace and the like.

Description

technical field [0001] The invention relates to nonlinear uncertain system control, in particular to a two-speed adaptive proportional-differential control. Background technique [0002] For more than half a century, classical control (cybernetics) based on frequency-domain design methods and modern control (model theory) based on time-domain design methods have developed independently, forming their own methodological systems. In the practice of control engineering, the error between the control target and the actual behavior of the controlled object is easy to obtain and can be dealt with appropriately. Therefore, the prototype of the control strategy of "eliminating errors based on errors", that is, PID (Proportional-Integral -Derivative, PID) controllers have been widely used in the field of actual industrial control. For practical control engineering problems, since it is usually difficult to give a "description of internal mechanism", the control strategy given by mod...

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Problems solved by technology

Since the principle of PD control is to weight the present (P) and future (change trend D) of the error to form a control signal, although the effective control can be exerted as long as the two gain parameters of the PD controller are reasonably selected, however, the error and The differential of the error is two physical quantities with different attributes. The inventor believes that it is unreasonable to carry out independent weighted summation of the two physical quantities with different attributes to form a PD control law model:

[0003] (1) Not only violates the basic rules of arithmetic operations (physical quantities of different dimensions cannot be independently weighted and summed), but also cannot accurately understand the mathematical model of the PD control law in a physical sense;

[0004] (2) The mathematical model of the PD control law separates the two links of proportional and differential attributes and treats them independently, which leads to the fact that the two links of proportional and differential are independent of each other in the control process, and thus lack of coordination the scientific idea of ​​control;

[0005] (3) Because of the irrationality of the PD control law model, the tuning of PD parameters has been a major problem in the field of control science and control engineering for more than 80 years.

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