Abstract
With the goal of “carbon peaking and carbon neutral”, power systems are gradually developing towards high proportional power electronics and ultra-high voltage DC transmission. In order to ensure the reliability, safety, flexibility and economy of the power supply, it is extremely important to study the control strategy of the power system transmission circuit. In this paper, based on the principle of a three-phase bridge fully controlled rectifier circuit constructed by Insulated-gate Bipolar Transistor (IGBT), the control system of the circuit is improved by using PID closed-loop control strategy to construct a 6-pulse bridge circuit applicable to ultra and extra-high voltage DC transmission converters. The simulation model of the PID-controlled three-phase bridge fully controlled rectifier circuit is built by Simulink, and the rectification output waveform is obtained to analyze the rectifying effect. Meanwhile, the step response performance indexes of the PI control strategy and PID control strategy are compared and analyzed, and the influence of the introduction of each parameter of P, I and D on the model is analyzed. The circuit designed has the advantages of outstanding rectification performance and stable control system, which is of great value to improve the performance of the converter and ensure the stability of the power supply.