Transient Power Smoothing Control Strategy for Battery of Pure Electric Bus

Aiming at the problems of unreasonable power distribution of composite energy storage system in pure electric bus, this paper designs a fuzzy control strategy and a wavelet transform control strategy. We obtain the power curves of the battery and ultracapacitor and the system energy flow graph under the two control strategies when running different cycle conditions. The simulation results show that the two control strategies are effective in smoothing the battery transient power. Compared with the fuzzy control strategy, the wavelet transform control strategy makes the battery output power frequency lower, thereby extending the service life of the battery. In order to further verify the effectiveness of the control strategy, we establish an experimental platform for a pure electric bus drive system. The experimental results show that the proposed two control strategies have a significant effect in smoothing the transient power of the battery and improving the energy utilisation rate.