电动汽车用双向DC-DC变换器最优效率控制研究

Research on Optimal Efficiency Control Strategy of Bidirectional DC-DC Converter for Electric Vehicles

针对电动汽车复合能源系统中隔离双向DC-DC变换器采用传统单移相控制峰值电流和功率损耗过大的缺陷,提出一种基于双重移相控制的最优效率控制策略。首先分析了双重移相控制工作原理,建立了隔离双向DC-DC变换器功率损耗模型,然后分析推导了隔离双向DC-DC变换器功率损耗最小的条件及最优效率控制的实现方案,使双向DC-DC变换器工作在功率损耗最小状态,从而使系统效率实现最大化。最后通过实验验证了最优效率控制的正确性和优越性。

In view of the defects of the large peak current and large power loss of isolated bidirectional DC-DC converter with the traditional single-phase-shift（SPS）control used in the hybrid energy system of electric vehicles,an optimal efficiency control strategy based on dual-phase-shift（DPS）control is proposed.The operating principle of DPS control is first analyzed,and the power loss model of IBDC based on DPS control is established,then the constraint condition to minimize the power loss of IBDC,as well as the implement scheme of optimal efficiency control strategy,are analyzed and derived later,therefore minimal power loss and maximal efficiency are ensured in an IBDC converter.The experimental results verify the correctness and excellent performance of the proposed optimal efficiency control strategy.