三电平Buck-Boost变流器直流电容检测与均压

Direct Current-link Capacitor Detection and Voltage Equalization for Three-level Buck-Boost Converter

为提高三电平Buck-Boost双向变流器直流电容全寿命周期运行性能,这里提出一种基于LC谐振的高精度状态检测与均压控制方法,首先在变流器启动过程中通过主动构造LC谐振回路并利用变流器现有的电流传感器对直流电容状态实施检测,在此基础上根据检测出的电容状态实现直流电容均压精确控制。仿真与实验验证了该方法的可行性与有效性。

In order to improve the whole life cycle operation performance of the direct current-link capacitor of the three-level Buck-Boost bidirectional converter,a high precision state detection and voltage equalization control method is proposed based on LC resonance.Firstly,the LC resonant circuit is actively constructed during the start-up of the converter and the existing current sensor of the converter is used to detect the direct current capacitance state,based on which the direct current capacitance equalization is precisely controlled according to the capacitor state.Simulation and experiment verify the feasibility and effectiveness of the method.