A Charger Ripple Inhibition Strategy for Motor Train Unit Based on Compound Control

Chargers are important energy conversion devices for motor train units. As the design changed, the supporting capacitors inside the chargers of a motor train unit were removed. In this study, the low-frequency ripple characteristics of output voltage after such a design change were analyzed. On this basis, a novel compound control strategy integrating quasi-proportional resonant control, repetitive control, and PI control was proposed. Next, the inhibiting effect of this new compound control strategy on the output voltage ripple of chargers was explored. Then, the new compound control strategy was applied to the chargers of a motor train unit to verify its effects. As revealed by the computer experiment, the proposed new compound control strategy can effectively suppress the low-frequency ripples in the output voltage of chargers.