Parallel control method without output current sensing for 400-Hz inverters

Based on conventional droop control scheme, a novel active and reactive power sharing method is proposed for parallel operation of 400-Hz inverters. Compared with the existing methods, the proposed solution employs the single-loop resonant controller which ensures good voltage regulation. Moreover, the feedback sensors of the output currents are also removed by implementing it in a software routine, and the number reduction of sensors simplifies the hardware implementation without sacrificing the load sharing ability. In order to show the performance of the proposed system, two parallel-connected 400-Hz three-phase inverters were built and tested. Simulation and experimental results are presented to prove the validity and the improvements of the proposed control scheme.