A High Voltage DC Gas Circuit Breaker Based on Self-excited Oscillating Circuit

Abstract

The invention discloses a high-voltage direct-current gas breaker based on a self-excited oscillation circuit. By the gas breaker, fault current can be cut off under high nominal voltage classes. The gas breaker comprises a superconducting current limiter and a cut-off module which are in serial connection. The cut-off module comprises gas breaker bodies in parallel connection, a current conversion circuit formed by serial connection of a capacitor and an inductance, and a non-linear resistor oxidation energy absorbing device. The fault current passes the superconducting current limiter first, is limited by the same, and is cut off by the gas breaker bodies. The gas breakers extinguish arc by using self exciting to generate artificial zero crossing points. The high-voltage direct-current gas breaker is fast in response, low in current overload coefficient, simple in structure, low in size, low in overvoltage, safe and reliable, short-circuit current does not exceed current quench of the superconducting current limiter, and other devices can be protected.

Description

technical field [0001] The invention relates to the technical field of circuit breakers, in particular to a high-voltage DC gas circuit breaker based on a self-excited oscillation circuit. Background technique [0002] Due to the immature technology of high-voltage DC circuit breakers, the development of multi-terminal DC systems is limited, and it has become a bottleneck in the development and application of multi-terminal DC transmission technology. As for the emerging flexible DC transmission system, although the power electronic technology can directly control and protect the system, as the final protection unit, the DC circuit breaker is also indispensable. [0003] At present, the principles of the commonly used high-voltage DC circuit breakers are self-excited oscillation type, which excites the oscillation type and uses the current limiting device to limit the current first and then break the type. Using a current limiter to first limit the current and then break it...

AI Technical Summary

Problems solved by technology

There are two main reasons why current limiting technology has attracted attention: First, as the capacity of the power grid continues to increase, the level of short-circuit current also increases. Limiting short-circuit current can improve the safety and stability of the power system, the quality of power supply of the power grid, and the operation of the power grid. Flexibility; second, the existing power devices have low overload capacity, and the di / dt and du / dt that can be tolerated are limited. In order to prevent breakdown or damage to power devices when a fault occurs, a current limiter is required

Images