PWM Rectifier Fast Response Method for Electric Servo Loading System

Abstract

The electric servo loading system can more fully test the stability and dynamic performance of the motor body and controller, and is widely used in the research and development of flight control systems. The traditional dual PWM converter has hysteresis characteristics. When the load power is abrupt, especially when the load power is suddenly reduced, the DC output voltage of the PWM rectifier will fluctuate. Voltage fluctuations can be suppressed by increasing the capacitance of the DC side capacitors, but an increase in the capacitance capacity causes the adjustment time of the system to become longer and slows down the response speed of the system. By analyzing the fluctuation of DC output voltage caused by sudden load change, a variable feedforward control method for iq load power is proposed, which uses the method of compensating the active current on the grid side to achieve instantaneous active power balance on both sides. The simulation results show that the method reduces the DC capacitor capacity and improves the dynamic response speed of the system.

Keywords

• electric servo loading system
• three-phase pwm rectifier
• variable load power feedforward control