摘要
非隔离型双向DC/DC变换器广泛的应用于混合直流供电系统中,在低电压大电流的场合采用交错并联拓扑结构的双向DC/DC变换器具有显著的优势。基于超级电容与蓄电池的混合储能系统,采用状态空间平均法,以三通道交错并联Buck/Boost变换器在Buck模态的工作状态作为模型进行分析,推导出相电感电流连续模式(CCM模态)下的交流小信号状态方程及其等效模型,并得到了电路模型的开环传递函数。通过Matlab仿真得到整个系统开环幅频和相频特性曲线,并以此为依据优化设计控制器的补偿网络,提高了系统的稳定性和瞬态响应速度,最后进行实验验证,结果表明双闭环的控制策略实现了恒压限流且动态特性较好。
Non-isolated bi-directional DC/DC converter is wildly used in hybrid DC power supply system. Interleaved bidirectional DC/ DC converters play an important role in the low voltage large current situation. Based on supercapacitor-battery hybrid energy storage system, using state-space averaging approach, a small single mode of a 3-phase interleaved Buck-Boost converter operating in Buck mode is built, and an AC small-signal state equation and an equivalent circuit under The phase inductance current continuous mode (CCM mode) are obtained. The open-loop transfer functions of the circuit are presented. Then the amplitude-frequency curve and phase-frequency curve are plotted by a Matiab simulation, based on which the feedback loop compensation design is given to optimiza- tion design of the controller, improving system stability and dynamic response speed. The results of the experiment show that the double closed loop control strategy realizes constant voltage-current limiting and has good dynamic characteristic.
出处
《控制工程》
CSCD
北大核心
2014年第6期886-890,共5页
Control Engineering of China