Study On Resistor Type Superconducting Current Limiting High Voltage DC Circuit Breaker

HVDC transmission has already received extensive attention and application,especially the rapid development of voltage source converters and other technologies,and great progress has been made in the application of high-voltage multi-terminal direct current transmission and direct current transmission and distribution.HVDC transmission has a great advantage over AC transmission in the construction of transmission lines,power regulation,and stability,and is more suitable for large-capacity high-voltage long-distance transmission.In large-scale wind power and other new energy grid-connected technologies,high-voltage DC systems are used as a collection platform for distributed power,which can effectively solve the stability problems of voltage,frequency,and power angle in AC system power grids.One of the key technologies for Development of HVDC is the research of HVDC circuit breaker,which is facing many technical difficulties.On the one hand,the DC current has no natural zero crossing points,and the arc extinguishing is extremely difficult.On the other hand,the multiterminal HVDC power transmission has brought a large capacity fault current.Therefore,the research and development of HVDC circuit breaker that can turn off large capacity fault current rapidly is of great significance for the development of multi terminal HVDC.In this paper,various superconducting current limiters and different high-voltage DC circuit breakers have been studied in depth.Firstly,the properties and applications of superconducting tapes,the classification and working principle of superconducting current limiters are analyzed,and the corresponding physical modules and mathematical modules are established,The Matlab/Simulink simulation software shows that the resistive superconducting current limiter has a good current limiting effect.Then,the structure and working principle of the traditional high-voltage direct current circuit breaker and the structure and working principle of the improved high-voltage direct current circuit breaker are analyzed.A high-voltage DC circuit breaker based on resistive superconducting fault current limiter is proposed in this paper.The circuit breaker consists of two parts:current limiting and turn off.When the line fails,the first limiting part triggers the SFCL,transit from superconducting state to normal state,produce resistance to limit the fault current,and fault current transferred by full controlled IGBT and arrester parallel combined into the branch,to further reduce the fault current,and the isolation switch is reliable to disconnect and isolate the fault line.The feasibility of the circuit breaker to break large fault current is verified by Matlab/simulink simulation.And in the Matlab/Simulink,the analysis of the circuit breakers with different values of the current limiter shows that the selection of the blocking value of the superconducting current limiter should take into account the interruption capacity of the circuit breaker,the rated voltage and the insulation level.