The balanced neutral point(NP)potential is a necessary condition for the safe and reliable operation of neutral point clamped three-level converter. This paper proposes a modulation strategy
which can maintain the balanced NP potential in the full power factor and full modulation index ranges
and featured with only three switching actions in one switching cycle. An NP potential recovery algorithm suitable for the proposed modulation strategy is also proposed. Compared with the carrier-based pulse width modulation and the virtual space vector modulation strategies
the proposed modulation strategy can reduce the switching loss to a great extent
and has good output voltage waveform quality and strong NP potential control and recovery capabilities. Finally
the proposed modulation strategy is compared with other existing modulation strategies by experiments to verify its feasibility and superiority.