SiC based High Efficient 180 Watt Power Supply For AC Drive Application

Abstract

In the present era, silicon semiconductor devices are being replaced with compound semiconductor devices such as Silicon Carbide and Gallium Nitride. The new compound semiconductors have many advantages as compared to silicon devices in terms of higher thermal conductivity, higher electronic mobility, higher saturation drift velocity, more breakdown field, higher switching frequency, and many more. But due to the change in their properties, the voltage level of the gate driver also change which needs to be considered while designing circuits. SiC and GaN-based devices are available for handling high voltage stress up to 1700V DC. The SiC devices have less on-state resistance, low parasitic capacitance and can be operated at very high switching speed so they will have lower losses compared to silicon devices and thus would increase efficiency. The project requires to operate for a wide input range of DC supply from 220V to 1200V with an output power demand of 180W. Flyback topology is preferred as it would provide electrical isolation and would have less number of components count and less costly compare to other isolated topology such as push-pull, forward, and full-bridge. But the voltage stress face by the switching devices is more then the input voltage. The maximum stress faced by the flyback converter is summation of maximum input voltage, reflected voltage, and spikes due to leakage inductance and parasitic capacitance. Thus the maximum voltage stress for the required wide input range would not have devices which can handle such high voltage stress. So to share the voltage stress, two switch series connected topology is selected. So the project SiC-based high efficient two-switch flyback converter topology is suited best for the specified requirement.