基于L-LLC谐振双向变换器的储能装置接口电路及控制策略研究

Research on Energy Storage Interface Circuit and Its Control Principle Based on the L-LLC Resonant Bidirectional DC-DC Converter

针对微网柔性并网系统中储能装置接口电路运行效率低、动态性能差的问题,提出一种基于PI或PID与最优轨迹混合控制的L-LLC谐振双向全桥变换器(L-LLC resonant bidirectional DC-DC converter,L-LLC BDC),实现了输入侧开关管的零电压开通和输出侧整流管的零电流关断,显著提高了变换器的动态性能,相对于最优轨迹控制,大量减小了运算的复杂度,提高了开关管的开关频率。采用状态平面法从理论层面对L-LLC-BDC的运行状态及特性进行了详细描述,在此基础上设计了储能装置接口电路控制系统。仿真结果表明,基于PI或PID与最优轨迹混合控制的L-LLC-BDC储能装置接口电路理论分析的正确性和动态性能的优越性,保证了微网柔性并网系统的运行性能。

Aiming at the low operating efficiency and poor dynamic response of energy storage interface circuit for flexible interface of connecting microgrid to power grid,the principle of PI or PID and optimal trajectory hybrid control based on the L-LLC resonant bidirectional DC-DC converter(L-LLC BDC)is proposed.It realize zero-voltage switching and zero-current switching for input switches and output rectifiers respectively,besides,it not only significantly reduce the computational complexity and further increase switching frequency,but also improve dynamic response of the converter remarkably.Using state-plane analysis,the operation status and characteristics of L-LLC-BDC are described in detail,based on that,the control system of the energy storage interface circuit is designed.In view of the principle of PI or PID and optimal trajectory hybrid control based on the L-LLC-BDC,the simulation shows that the correctness of theoretical analysis and the superiority of dynamic response and the operation performance of flexible interface of connecting microgrid to power grid is guaranteed.