Modified SPWM Technique with Zero-Sequence Voltage Injection for a Five-Phase, Three-Level NPC Inverter

Abstract

This article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the reference modulating signals; hence enabling the effective utilization of the DC-link voltage. Balanced split-input DC-link voltages were achieved through further incorporation of adjustable voltage-dependent variables into the reference signals. The dynamic performance of the control approach is demonstrated through simulations and experiments on a laboratory inverter prototype; the results are well presented.

Keywords

• SPWM
• NPC inverter
• multilevel inverter
• five-phase induction motor
• DC voltage balancing