摘要
由双向DC/DC变换器、微网逆变器组成的级联系统中,选择buck-boost电路为前级变换器,当其工作于升压状态时,由于boost变换器小信号模型中存在1个低频右半平面(RHP)零点,使得前级系统带宽变窄,仅采用单电压闭环控制可能会引起前后级系统带宽不匹配,导致直流母线电压产生低频振荡且系统响应速度慢,级联系统稳定性差。采用滑模控制方法设计前级变换器系统,仿真显示,直流母线电压无低频振荡,响应速度较快,系统稳定性提高。
In a cascade system consisting of a bidirectional DC/DC converter and a microgrid inverter,a buck-boost circuit is selected as the first stage converter.When it operates at boost mode,due to the presence of a low-frequency right half-plane(RHP)zero in the small-signal model of the boost converter,the bandwidth of the first stage system is narrowed,and only the single-voltage closed-loop control may cause the bandwidth of the first and second system to be mismatched,it will lead to low frequency oscillation of DC bus voltage,slow response speed and poor stability of cascade system.The former converter system is designed by using sliding mode control method.The simulation results show that the DC bus voltage has no low frequency oscillation,the response speed is fast and the system stability is improved.
作者
刘旻超
LIU Minchao(Technician Training Center, State Grid Jiangsu Electric Power Co., Ltd., Suzhou 215004, China)
出处
《镇江高专学报》
2020年第1期44-48,共5页
Journal of Zhenjiang College
关键词
分布式发电
储能系统
系统带宽匹配
级联稳定性
滑模控制
distributed generation
energy storage system
system bandwidth matching
cascade stability
sliding mode control
