POWER GRID REACTIVE COMPENSATION METHOD AND APPARATUS, AND GRID-TIED INVERTER

摘要

The present invention discloses a method for reactive power compensation of power grid, an apparatus for reactive power compensation of power grid and a grid-tied inverter. The method for reactive power compensation of power grid includes: detecting voltage of a power grid; when a voltage magnitude of the detected voltage is lower than a preset normal voltage magnitude, determining an electric reference parameter corresponding to the voltage; determining a current pulse width modulation (PWM) mode according to the electric reference parameter corresponding to the voltage, where the PWM mode includes: a unipolar modulation mode and a bipolar modulation mode; and outputting reactive power by using the current PWM mode, so as to implement reactive power compensation for the power grid. In this solution, the current PWM mode is determined through the electric reference parameter corresponding to the detected voltage at the time of voltage dip of the power grid, so as to effectively combine the unipolar modulation mode and the bipolar modulation mode in one current period; then at the time of voltage dip of the power grid, effective reactive power compensation is performed on the power grid, and meanwhile the switching loss and the inductance loss are reduced.