Design of Four Quadrant Pulse Rectifier Based on Composite Phase-locked Loop

The design of four quadrant pulse rectifier for the traction drive system of electric power locomotive is introduced.The principles and instantaneous direct current control strategy of four quadrant pulse rectifier are discussed.Compared with hardware phase-locked loop and software phase-locked loop,a combination of hardware and software composite phase-locked loop is proposed,which can accurately track the phase of line voltage.Effects of the grid voltage disturbance on the rectifier DC output voltage are analyzed,when the grid voltage disturbances in 10%,DC output voltage reaches steady state rapidly after the small fluctuations.The experimental results show that the input current of pulse rectifier has strong anti-interference ability,and can accurately follow the input voltage to achieve high power factor close to 1.