Research on Three-Level Bi-Directional DC-DC Converter and Its Control Strategy Used for Energy Storage System of Electric Wheeled Tramcar

According to the working characteristics of mining 730E electric wheel tramcar which produces a lot of electric energy when it goes downhill and decelerates, an energy storage scheme is proposed. The traditional two-level DC-DC converter has high voltage stress and large output current ripple, and the energy storage system of mining 730E electric wheel tramcar needs two-way flow of energy. In this paper, three-level Bidirectional DC-DC converter is selected as the energy storage system. Based on the analysis of the working principle of three-level Bidirectional DC-DC converter, the control strategy is studied. The simulation model is built on MATLAB / Simulink platform, and the control algorithm of three-level Bidirectional DC-DC converter is simulated and optimized. The advantages of three-level Bidirectional DC-DC converter topology are proved, and the control of bus voltage, flying capacitor voltage and battery charging and discharging current is realized.