Buck – Boost Voltage / Current Source Inverter with Space Vector Pulse width Amplitude Modulation

This paper proposes a space vector pulse width amplitude modulation (SVPWAM) method for a buck–boost voltage/current source inverter. For a voltage source inverter, the switching loss is reduced by 87%, compared to a conventional sinusoidal pulse width modulation (SPWM) method. For a current source inverter, the switching loss is reduced by 60%. In both cases, the power density is increased by a factor of 2 to 3. In addition, it is also verified that the output harmonic distortions of SVPWAM is lower than SPWM, by only using one-third switching frequency of the latter one. A 1-kW boost-converterinverter prototype has been built and tested using this modulation method. The maximum overall system efficiency of 96.7% has been attained at full power rating. The whole system power density reaches 2.3 kW/L and 0.5 kW/lb. The numbers are remarkable at this power rating. As a result, it is feasible to use SVPWAM to make the buck–boost inverter suitable for applications that require high efficiency, high power density, high temperature, and low cost. Such applications include electric vehicle motor drive or engine starter/alternator.