High-voltage isoltated multiple outputs DC/DC power supply for GCT gate drivers in medium voltage (MV) applications

In this paper a 960W Series Isolated Power Supply (SIPS) is introduced. The proposed design is a special high frequency soft switched DC/DC converter, integrating 12 series isolated power supplies in one module. Each power supply generates a regulated dc voltage of (20±0.5V), isolated for voltages up to 15kV. Each power supply is capable of supply up to 80W for gate drivers of GCT or SGCTs generally used in Medium Voltage applications. The proposed design uses 12 CTs each comprising of one primary and three secondary turns. This makes the design very effective in terms of cost, power density and voltage isolation. The voltage isolation levels are verified through extensive Partial Discharge and Impulse tests. The paper includes design guidelines and optimization approach as well as experimental results and efficiency studies.