DC power grid topology based on coupling transformer under high impedance grounding and fault positioning method thereof

Abstract

The invention relates to a DC power grid topology based on a coupling transformer under high impedance grounding, and a fault positioning method thereof. The positioning method comprises the followingsteps: firstly detecting a DC voltage signal of a DC line through a way of detecting the voltage signal, initially judging whether the fault occurs; after judging that the fault occurs, controlling to short-circuit a high-impedance grounding line arranged between the neutral point of the coupling transformer and the ground, in this case, the fault current can produce in the DC line since the highimpedance arranged between the neutral point of the coupling transformer and the ground is short-circuited; and then detecting the fault positioning according to the fault current. Therefore. The fault positioning method is suitable for the DC power grid topology based on the coupling transformer high-impedance grounding, the fault positioning can be realized, and then the fault overhauling can be performed according to the fault location, and a fault positioning demand of the DC power grid topology based on coupling transformer high impedance grounding can be satisfied; furthermore, the fault positioning method is simple and practical, easy for engineering field implementation, and capable of improving the reliability of the DC power grid.

Description

technical field [0001] The invention relates to a direct current power grid topology and a fault location method based on a high-impedance grounding connection transformer. Background technique [0002] The DC distribution network can alleviate the contradiction between the limited corridors of the AC grid site and the high load density, and has the advantages of better receiving DC loads, an obvious trend of end-user load DC, better high-quality electricity demand, and easy distributed energy and energy storage. Therefore, the DC distribution network will be the main development direction of the distribution network. [0003] As a new power distribution technology, DC distribution network is in the initial stage of development, such as figure 1 As shown, the connected transformer (connected transformer) is grounded through a high resistance (resistance R with a very large resistance) is a typical topology of the DC distribution network, that is, the neutral point of the co...

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Problems solved by technology

[0004] The purpose of the present invention is to provide a fault location method based on the high-impedance grounded DC power grid topology of the connected transformer, which is used to solve the problem of fault current poles in the fault loop when the DC power grid topology based on the connected transformer is high-impedance grounded. Small, unable to realize the problem of fault location through current

At the same time, the present invention provides a DC power grid topology based on the high-impedance grounding of the connected transformer, which is used to solve the problem that the fault current in the fault loop is extremely small when the DC power grid topology based on the connected transformer is high-impedance grounded. The problem of fault location

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