This paper proposes a method to eliminate abnormal output voltages generated in three-level hybrid active neutral-point clamped (ANPC) inverters.
The hybrid ANPC inverter is a topology which silicon (Si) devices are replaced with silicon-carbide (SiC) devices in part from conventional ANPC
topology. The hybrid ANPC inverters have the advantages of high-switching frequency and low power switching loss due to the SiC devices. In this
hybrid ANPC inverter, abnormal output voltages occur when the polarity of the output pole voltage is changed from positive to negative. The cause of
the abnormal voltages is the switching time difference between Si and SiC devices, and it is various from a few nano-seconds to a few micro-
seconds. These abnormal output voltages need to be eliminated as it leads to degraded output power quality in the hybrid ANPC inverters. The
proposed switching method effectively eliminates the abnormal output voltages and reduces output current distortion. The performance of the
proposed method is verified using a prototype of the new three-level hybrid ANPC inverter type through both simulations and experiments.