Control Strategies of Hybrid Power Supply System Based on Droop Control

Along with the rapid development of Chinese railway, EMU has already become a widely accepted travel tool. But conventional EMU has a high dependency on the overhead contact line (OCL) network as well as a potential risk of injecting harmonics into the OCL network, which may lead to an oscillation in the OCL network. This paper majorly studies the control strategies of hybrid power supply system for the first diesel electric multiple units in China. Due to the natural restriction of permanent magnet synchronous generator (PMSG), the output voltage of the alternator cannot be controlled directly. To solve this problem and achieve a good power allocation, the droop control is applied to build the control system of hybrid power supply system. The result of experimental prototype test shows that the control strategies work well and achieved a good power allocation in its operation.