Variable universe fuzzy control for excitation system of HTS machine

Abstract

Abstract.The generator is an important component of the power system and, as a prerequisite for the normal work of the generator; one of the preconditions of excitation of a system running well will directly affect the operation of the motor characteristics and heavily influence the normal operation of the power system. In the excitation system, the control portion of the excitation system is the key to whether a system can effectively resist all kinds of emergencies. Regarding the excitation system of a high temperature superconducting machine, this paper proposes the design of an excitation system control strategy. Combining fuzzy control and conventional PID control strategy, the proposed composition has the advantages of an excitation control strategy, which can achieve a precise control purpose, and provides good adaptive ability and robustness. And on this basis, the proposed composition seeks to combine variable universe fuzzy control, to further improve the control precision of the system. The fuzzy PID control system simulation model and the variable universe fuzzy PID control are investigated. Results are compared and indicate that the variable universe fuzzy PID control demonstrates better dynamic and static performance.

Enhanced variable universe fuzzy proportional–integral–derivative control of structural vibration with real-time adaptive contracting–expanding factors

“…Each input and output variable is mapped to the fuzzy domain using membership functions. Each input variable is modeled by seven triangular membership functions in the fuzzy domain g i = [− D i , D i ] ( i = 1, 2) as shown in Figure 3, where D is the domain boundary (Zhang et al, 2016). The fuzzy linguistic variables defining the fuzzy domain are listed in Table 1.…”

“…Two kinds of CEFs, expressed as mathematical function, have been reported with different definitions and properties (Li et al, 2002). However, the parameters in the CEFs are constants which are subjectively determined (Zhang et al, 2016). Optimal control cannot be achieved because these parameters cannot be changed with system feedback.…”

Master and Auxiliary Compound Control for Multi-Channel Confluent Water Supply Switching Control Based on Variable Universe Fuzzy PID

“…In reference [12], a fuzzy PID controller is designed to control the steam temperature of the supercritical lignite boiler, and its excellent response speed and stability are verified through simulation. References [13,14] introduce the idea of a variable theory domain on the basis of a fuzzy PID control, which overcomes the shortcoming of the limited control rules of a fuzzy PID controller, further increases the controller's adaptive ability, and improves the dynamic characteristics of the control system. In addition, references [15][16][17] use variable universe fuzzy PID control in different applications, and the control effect is significant.…”