Frequency conversion unit supercapacitor assembly charge-discharge control loop

The invention relates to a frequency conversion unit supercapacitor assembly charge-discharge control loop with power-factor correction. A supercapacitor assembly which is formed by super capacitance is used as an energy storage capacitor device, the energy storage capacity is big and the charge-discharge speed is quick. Higher demands for rapid braking and speeding of a frequency conversion unit are met. A cross double Boost power-factor correction circuit in parallel is adopted to reduce the switch loss and improve the quality of the energy. A multi-level bidirectional direct current DC- DC converter is used as an interface of an energy storage element and a direct current bus to reduce the switch loss and the filter inductance and improve the efficiency of a convertor.