Development of cast resin multisecondary 1600kVA transformer for Regulated High Voltage Power Supply- A prototype

Regulated High Voltage Power Supplies (RHVPS) are commonly used in high-energy particle accelerators. RHVPS is a modular power supply in which kV level modules (40 or 80#) are cascaded to generate desired level of voltage/power [1]. One of the most challenging tasks involved is to provide input power to number of rectifier modules with required isolation (inter-winding and winding to ground). This is accomplished by deploying multi-secondary (large numbers, say 40 secondaries) transformers. This RHVPS concept was realized for the first time in the country with development of oil filled multi-secondary transformer. A pair of 3.3MVA, 11kV/ (940Vx40) has been successfully demonstrated, isolation of 6kVDC (inter-winding) and 160kVDC (all secondary to ground) tested. The next generation power supplies are unitized with indoor installations. This has created the demand for dry type multi-secondary transformers in compliance with safety regulations. This paper presents manufacturing issues and testing of the prototype resin cast coil. On the manufactured prototype, inter-winding isolation is tested up to 6kVDC and 125kVDC with respect to ground.