Figure 7 shows the waveforms of a DC converter composed of one circuit. The reference current of each circuit is 25A, so the total charging current is 100A. Ib1, Ib2, Ib3 and Ib4 are the output currents of charging unit 1, unit 2, unit 3 and unit 4, respectively. Ib is the charging current of the battery. Io1 is the output current of DC transformer. Figure 8 shows the waveforms of a DC converter composed of three interleaved circuits. The reference current of each circuit is 8.33A, and the reference current of each DC converter is 25A, so the total charging current is 100A. In steady state, Ib1 fluctuates between 23.75A and 26.8A, Ib fluctuates between 99.62A and 101.6A, Pbfluctuates between 5. Figure 9 shows the simulation waveforms of operation and stop test of multiple charging units, the charging reference current of charging unit 1 changes from 25 to 30A in 0.25 s, charging unit 2 starts operation from 0.03 s, charging unit 3 stops operation from 0.2 s, and the charging reference current of charging unit 4 changes from 25 to 15A in 0. Figures 10 shows experimental waveforms of DC charging pile with resistive load. At the beginning, the DC converter uses current creep control, when the charging current reaches 120A, it enters constant current charging mode. Uabis the line voltage of the grid. Figure 11shows the adjustable resistive load device. The adjustable resistive load devic. The main components of the DC charger cabinet include: controller, man–machine components, charging modules, lightning protector, leakage protection, circuit breaker, contactor, DC meter, fuse, air cooling system, cabinet body, etc. The main components of the charging pile include: controller, man–machine components, lightning protector, contactor,.