Increased power capability of standard drive inverters by sequential switching

This paper presents a new approach for increasing the power capability of standard two level voltage source inverters while increasing the effective PWM frequency by sequential switching of parallel connected inverters. The improved power capability and increased PWM frequency is used for an electrical test bench to test drive inverters under real power conditions. Thereby the parallel connected inverters of the test bench can be of the same type as the inverter under test. Hence there exists no power limit for drive inverter testing with respect to the product range of the manufacturer.