一种中点共模注入功率解耦电路

A Midpoint Common Mode Injection Power Decoupling Circuit

单相逆变器在许多领域有着广泛的应用,但存在固有的二倍频问题,二倍频波动易造成系统不稳定。文中提出一种中点共模注入功率解耦电路,该拓扑优点在于无需额外开关器件,仅利用H桥逆变器两侧原有支撑电容和滤波电容,即可缓冲二倍频功率。整个解耦控制算法简单,易于在单相差分逆变器中实现。另一个特点在于该拓扑仅利用交流侧滤波电容和直流侧支撑电容中点相连构造半桥型差分逆变器结构,交流侧电容能正负运行,同时减小了解耦电容耐压值。半桥结构不仅提高了电容利用率,在电容的选择上也促进了功率密度提高。仿真和实验结果进一步证明该方法有效的抑制直流侧二倍纹波脉动,同时数据证明该拓扑解耦后能有效的提高系统效率。

Single-phase inverters are widely used in many fields,but there are inherent double frequency problems,and double frequency fluctuations can easily cause system instability.This paper proposed a mid-point common-mode injection power decoupling circuit.The advantage of this topology is that no additional switching devices are needed,and only the original support capacitors and filter capacitors on both sides of the H-bridge inverter can be used to buffer the double frequency power and realize the solution.The entire decoupling control algorithm is simple and easy to implement in a single-phase differential inverter.Another feature is that the topology uses the AC-side filter capacitor and the DC-side support capacitor to be connected at the midpoint to construct a half-bridge differential inverter structure.The AC-side capacitor can operate in positive and negative directions while reducing the withstand voltage of the decoupling capacitor.The half-bridge structure not only improves the utilization of the capacitor,but also promotes the increase of power density in the selection of the capacitor.The simulation and experimental results further prove that the method can effectively suppress the double ripple on the DC side,and the data proves that the topology can effectively improve the system efficiency.