Dynamic characteristics of boost inverter with waveform control

The input current of single-phase inverter typically has an AC ripple component at twice the output frequency. The low-frequency current ripple can cause a reduction in both the operating lifetime of its DC source and the energy conversion efficiency of the system. In this paper¹, a proposed waveform control method which can eliminate such a ripple current in boost inverter system, is discussed. The characteristics of the waveform control method in boost inverter under input voltage or wide range load variations are studied. It is validated that by including an output current feedback loop into the waveform control method, the reference voltage of the boost inverter capacitors can be instantaneously adjusted to match the new load, thereby achieving ripple mitigation for a wide load range. With the control and feedback mechanism, there is minimal level of 2ω component at the DC bus during steady state, and the transient response is rapid with negligible effect on the output voltage. Analysis, simulation and experimental results are presented to support the investigation.