A method for the parallel inverter output power imbalance suppressing system

The present invention discloses a method of inhibiting the output power of the inverter parallel system unbalanced, S01: in each switching cycle, two parallel sampling AC side of the inverter output phase voltage of the three-phase current side and the distribution network ; S02: a current path between the inverter converts the coordinate system, resulting in component d, q-axis; S03: the distribution grid side three-phase voltage obtained through the voltage amplitude of the PLL processing and distribution Ud net phase angle θ; S04: obtaining three-phase unbalanced disturbance path currents ib and d, q-axis component ibd, ibq; S05: sampling the DC bus voltage Udc side, the system DC voltage given as a difference value U * dc process, after PI controller as a current setpoint value i * d; S06: the ibd, ibq as disturbance current imbalance, to which a disturbance applied to inverter current imbalance treated, the other inverter is not added disturbance; three output duty cycle information corresponding to the IGBT with the thyristor trigger switch controls the corresponding phase of the inverter and the grid work. Quick adjustment and improve the reliability of power supply.