A Fault Current Controller for Current Bidirectional HVDC Transmission Network

Abstract

The invention discloses a fault current controller used for a current bidirectional high-voltage direct current power transmission network. The controller comprises a first hybrid unidirectional switch circuit and a second hybrid unidirectional switch circuit, wherein the first hybrid unidirectional switch circuit is connected to a pole line, and the second hybrid unidirectional switch circuit isconnected to a neutral line. The controller also comprises a pole line electric reactor and a high-temperature superconductor, wherein the pole line electric reactor and the high-temperature superconductor are connected to the pole line, and the pole line electric reactor is connected between the high-temperature superconductor and the hybrid unidirectional switch circuits. By use of the controller, a current bidirectional control flow limiting function can be realized, and the controller has perfectly symmetrical circuit topology and is not affected by a power grid tidal current direction. The turning-on duty cycle of electronic power switch is regulated, current-limiting current bidirectional continuous setting can be realized, so that the controller exhibits wide range adaptation and can be suitable for short circuit situations from different degrees.

Description

Technical field [0001] The invention belongs to the technical field of direct current transmission, and specifically relates to a fault current controller for a current bidirectional high voltage direct current transmission network. Background technique [0002] The DC transmission and distribution system started in the 1920s, because the technical reserves at the time were not enough to realize the functions of DC voltage conversion, power flow control, and fault interruption current limiting. This largely restricts the development of DC transmission grids. Nowadays, with the vigorous development of new materials such as power electronic semiconductor devices and related control technologies, high-temperature superconducting materials, and liquid metals, DC systems have been mentioned again and more because of their unique advantages over AC systems. The more it is used in the construction of new power transmission and distribution systems. However, with the increase of DC vol...

AI Technical Summary

Problems solved by technology

However, with the improvement of DC voltage level and power transmission power, traditional access current-limiting inductors or resistors are difficult to manufacture due to the large inductance and resistance values ​​required, single-function, high customization, and uncontrollable current-limiting size. It cannot meet the development requirements of the modern DC grid, thus bringing new challenges and opportunities to the fault current control of the DC grid

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