Enhancing the anti-islanding capability and power quality of microgrid through a series compensator

This paper presents an improved power quality control strategy based on inverter. In grid-connected mode, the series inverter between the microgrid and utility gird (UG) can compensate the power quality of the micro grid under the condition of the voltage fluctuation, imbalance, and harmonic distortion, and prevent the harmonic currents from microgrid flowing into the UG. Especially, when there is an instantaneous short circuit fault of the UG, the topology can also function well, enhancing the anti-islanding and fault tolerance capability, avoiding the transient process in the mode transfer and improving energy efficiency. In islanding mode, the series inverter is converted to the shunt inverter by switching ground, which can work as the shunt active power filter. The unified device is applied to two operating modes, saving the cost of operation. The effectiveness and reliability of the control strategy is certified through the Simulink.