A Three-Phase PWM VSI Line Termination Net for Load Overvoltage Cancellation

The feasibility of load overvoltage cancellation is investigated, induced by four-wire cables connection to hard-switching IGBT PWM VSI. The transmission line parameters of these cables are evaluated by taking into account any mutual coupling between wires, accurately defining signal termination net values. Conversely, power line termination net requirements are pointed-out to define practical LTN design concepts and benefits, accounting also for the composition of distributed and lumped second order responses due to parasitic load capacitance. The experimental results demonstrate the feasibility of the main proposal as well as a strong reduction of current ringing, confirming that the proposed design concept can be reliably effective in a wide range of load power and cable length.