Hybrid DC circuit breaker and protection method thereof

Abstract

The invention discloses a hybrid DC circuit breaker and a protection method thereof. The hybrid DC circuit breaker includes multiple through-flow branches, a transfer branch and an energy-absorbing branch, wherein the multiple through-flow branches are connected in parallel with respective power transmission lines of a DC bus branch through respective connection ports, a beginning end of the transfer branch is connected with through-flow branch lines, a tail end of the transfer branch is connected with tail ends of the multiple through-flow branches, the multiple through-flow branches share the one transfer branch, the energy-absorbing branch is connected in parallel with the transfer branch, the through-flow branch includes a mechanical switch and a diode rectifier bridge assembly, the mechanical switch and the diode rectifier bridge assembly are arranged in series on the lines of the through-flow branches, and the transfer branch includes a diode rectifier bridge assembly with a current limiting resistor. The hybrid DC circuit breaker is advantaged in that the hybrid DC circuit breaker can greatly reduce the number of IGBTs used, improve economic performance and reduce cost of manufacturing, can further improve operating efficiency of the DC circuit breaker and guarantee safe and reliable operation in the DC circuit breaker protection process.

Description

technical field [0001] The invention belongs to the technical field of DC circuit breakers, in particular to a hybrid DC circuit breaker and a protection method thereof. Background technique [0002] Compared with traditional DC, flexible DC transmission has more advantages in improving power quality, long-distance transmission, new energy access, and asynchronous networking. In the future development of power systems, multi-terminal DC transmission based on voltage source converters will become one of the main directions. With the development of DC transmission, the transmission power of DC lines increases, and the volume of DC equipment and the difficulty of manufacturing equipment also increase. In many DC equipments, DC circuit breaker technology is an important factor limiting the development of multi-terminal DC transmission. The lack of a natural zero-crossing point of the DC fault current, and the linear increase of the short-circuit current within a few millisecon...

AI Technical Summary

Problems solved by technology

[0004] However, in the existing hybrid DC circuit breakers, a large number of IGBTs are required, and the cost of IGBTs is high, so that the economy is not high; Low; because the current transfer cannot be realized quickly and efficiently in the existing circuit breaker, so that it cannot achieve safe and reliable work during operation

Images