In order to solve the problem of supplying energy to 500 kV DC circuit breakers

this paper proposes an electromagnetic power supply system at 50 Hz. A 500 kV DC high-voltage isolated transformer is used to transmit power to the circuit breaker platform at the DC bus potential

and then the power is transmitted to the power components at different potentials inside the circuit breaker through the isolated transformer on the platform. Ten-grade 50 kV transformers are cascaded to form a 500 kV DC high-voltage isolated power supply transformer

and eight-grade 50 kV transformers are cascaded to form the isolated transformer used on the platform. The inherent distributed capacitance of the transformer itself causes the uneven voltage of the transformer in the power supply system

and thus the insulation breakdown of the transformer occurs

resulting in the failure of the power supply system. Firstly

the distributed capacitance parameters of the 500 kV DC high voltage isolated power supply transformer and the isolated transformer on the platform are extracted.Then

according to the extracted distribution parameters

the voltage equalization design of the power supply system is completed. Finally

the correctness of the parameter configuration is verified through two simulation analysis methods.The results show that the 500 kV DC high-voltage isolated power supply transformer of the power supply system adopts a voltage equalization method of 8 nF capacitor and 200 MΩ resistor in parallel

and the transformer on the platform of the power supply system adopts a voltage equalization method of 200 MΩ resistor

which can meet the operation requirements of 500 kV high voltage DC circuit breaker. The research provides a valuable reference for power supply design of DC circuit breaker.