A space vector PWM algorithm for Z-source three-level NPC inverters

Existing dual Z-source networks three-level neutral-point-clamped (NPC) inverters are costly with numerous passive elements. To overcome this disadvantage, a topology of Z-source three-level NPC inverter with single Z-source network is introduced. It only needs single input power source and LC impedance network, while achieving the same voltage-boost capability as the inverter using dual Z-source impedance networks. A suitable space vector PWM scheme for Z-source three-level NPC inverter is proposed, which is simple due to the use of two-level modulation principles based on the idea of origin shifting. By carefully inserting the shoot-through vectors into the equivalent zero vectors, the inverter not only maintains the desired boosted ac output voltage but also reduces the switching loss in a maximum extent. Last, simulation and experimental results are included for verifying the validity of the proposed SVPWM algorithm.