A novel power supply configuration for GCT gate drivers

In this paper, a high frequency soft switch DC/DC converter is proposed for power semiconductors (e.g., GCT, GTO). The proposed design includes six Parallel Isolated Power Supplies (PIPS), each supplying a GCT gate driver at regulated 20Vdc. Unlike self-powered supply which is design for powering up the switch gate driver for only one specific converter topology such as CSR, VSR, VSI, etc., our design features a general power supply for powering the gate drivers of switches used in different converter topologies where high voltage insulation level is required, such as Medium Voltage Neutral Point Clamped to PWM CSI converters. One isolated power supply is currently being tested for a 40W output power while operating with a switching frequency of 120kHz. This has been made possible while ensuring zero voltage switching (ZVS) for the main converter within the power supply. Since PIPS operates in ZVS, the switching losses are low and hence the efficiency of the proposed converter is high. Design of the converter and transformer with multiple outputs are verified by simulation and experimental results. Based on the comparisons with other existing converter configurations, we show that PIPS achieves high efficiency, and significant reduction in the cost and size of the power supply.