High Voltage DC Power Supply for Intelligent Power Modules

Although this power supply design is specific to the Intelligent Power Modules (IPM), the concepts and circuit design may be used for any power supply that requires high voltage output up to 400V DC and 6 A. It is an unregulated power supply, DC output is dependent on AC input.  The circuitry includes a passive EMI filter consisting of elements C5, C6, C7, C8, C9, C10, T1, and a BR1 25 A/600V rectifier block, R3 NTC for inrush current protection, and a relay RL1 for soft powering up and reducing conduction losses in steady-state operation. 2 x electrolytic capacitors C3, C4 are used for buffering the rectified DC bus voltage. It is advisable to use a heatsink on the bridge rectifier. Inrush current circuit requires 12-15V DC @ 50mA power supply. Choose appropriate fuse as per current requirement.