An analysis and a solution for inrush current elimination for three-phase PWM voltage source inverters

This paper analyzes the cause of the inrush current at the starting time of the three-phase PWM voltage source inverters (VSIs) based on d-q synchronous reference frame. Then the simple method for solving the problem is proposed. The proposed technique can be applied to either active power applications such as Battery Energy Storage Systems (BESSs) or reactive power applications such as STATCOMs (Static Synchronous Compensators). The computer simulation and experimental results well agree with each other and verify that the proposed solution can completely eliminate the inrush current of the inverters. In addition, the proposed technique does not affect the overall system performance and does not require any additional control or power circuitry. The experimental system is DSP (Digital Signal Processor) based and has a power rating of 2 kW, as a BESS, and 2 kVAR, as a STATCOM.