中文摘要：

随着电动及混合动力汽车的普及,汽车废旧电池再利用己成为值得关注的问题。提出一种多端口功率变换结构,将多个废旧电池组和光伏接入直流母线,成为直流微网储能与发电节点。利用主从协调控制结构实现对每个电池组输出功率比例的控制;每组废旧电池本地控制器在系统启动阶段注入伪随机二进制信号（PRBS）激励得到每组电池组的频率特性来评估电池状态;根据指令控制输出电压并使能功率双向流动。利用仿真和实验手段对功率为360 W、输出电压为60 V的样机进行验证,证明了系统设计和功率控制策略的有效性。

英文摘要：

As the electric vehicle market is expanding rapidly, recycling and reusing of secondary life vehicle batteries brings a lot of attentions.A multi-port topology is proposed, which integrate multiple secondary life battery packs into the DC micro-grid with photovoltaic power.By using the master-slave control structure,the output power ratio of each batery pack can realized.The local controller can assist status evaluation of battery pack by injecting pseudo random binary signal（PRBS） in the close-loop.Bidirectional power flow is enabled.Simulation and experimental verification of a 60 V/360 W prototype verify the correctness of the system design and the effectiveness of the strategy.