Design and implementation of a 10 kV/10 kW high-frequency center-tapped transformer

Abstract

High voltage high-frequency (HVHF) transformers have a crucial part in the realization of high voltage direct current (HVDC) isolated power supplies. Nevertheless, they are the bulkiest component in the system besides being one of the major contributors to the power losses. Special care is therefore required to design HVHF transformers. The main objective of this paper is to design and implement a high voltage (10 kV), high-frequency (50 kHz) center-tapped transformer with high efficiency, small size, and low cost. The proposed transformer is designed as part of a 100 kV, 10 kW DC/DC converter for supplying power to a particle accelerator. The proposed transformer steps up the input voltage (500 V) to 10 kV. Then, a five-stage full-wave Cockcroft-Walton voltage multiplier (CWVM) is used for boosting the voltage to 100 kV. A detailed step-by-step design guideline for designing an HVHF transformer is also presented. To reduce the transformer's parasitic capacitance, the secondary windings are wrapped in segments. This taken approach has been illustrated in the paper and later verified through finite element analysis (FEA). The FEA analysis shows that the transformer parasitic capacitance has reduced significantly. Following the presented design guideline, the implemented prototype transformer has been built and later tested with a single-stage CWVM. The experimental results demonstrate that the prototype transformer has successfully met the design requirements including the small size, less weight, and low-cost objectives.