A novel arrangement for balancing the capacitor voltages of a five level diode clamped inverter

This paper introduces a novel capacitor voltage balancer arrangement for five-level inverters fed from a single DC link supply, and provides a full discussion of its operation and performance. The circuit has the form of a 4th power electronic leg with similar device ratings to the output leg, and with two added inductors. It maintains correct voltages at each of the inverter levels. The circuit is effective at all output modulation depths and frequencies, and functions correctly when the load regenerates.