Control method of Three-phase Four-leg converter based on repetitive control

[摘要] The research chose the magnetic levitation force of wind power generation system as the object. In order to improve the power quality problem caused by unbalanced load in power supply system, we combined the characteristics and repetitive control principle of magnetic levitation wind power generation system, and then an independent control strategy for three-phase four-leg converter was proposed. In this paper, based on the symmetric component method, the second order generalized integrator was used to generate the positive and negative sequence of signals, and the decoupling control was carried out under the synchronous rotating reference frame, in which the positive and negative sequence voltage is PI double closed loop, and a PI regulator with repetitive control was introduced to eliminate the static error regarding the fundamental frequency fluctuation characteristic of zero sequence component. The simulation results based on Matlab/Simulink show that the proposed control project can effectively suppress the disturbance caused by unbalanced loads and maintain the load voltage balance. The project is easy to be achieved and remarkably improves the quality of the independent power supply system.

[发布机构] School of Electrical Engineering, Shandong University, Jinan; 250061, China^1

[效力级别] 无线电电子学

[关键词] Fundamental frequencies;Magnetic levitation force;Negative sequence voltage;Power quality problem;Rotating reference frame;Second-order generalized integrators;Wind power generation systems;Zero sequence components