I need a transformerless inverter which generates a 3 phase 230 VAC modified sine wave output from 325 VDC input. Unfortunately, it seems these are rare, at least high power models. Can a VFD (with DC bus) be used instead? As I understand it, most modern VFD use Sinusoidal PWM. Are there any models which can be configured to output "six step" instead of PWM?