A fault detection circuit and inspection method for substation direct current system

Abstract

The invention discloses a substation direct-current system fault detection circuit and a substation direct-current system fault detection method. The method includes the following steps that: the on-off of relays on the circuit is controlled, and data to be measured under different states are measured; the values of the equivalent resistance to ground of a positive bus-bar and a negative bus-bar is calculated, whether a grounding fault exists in a direct current system is judged; the on-off of capacitor circuits connected with the positive bus-bar and the negative bus-bar is controlled, the magnitude of to-be-measured resistor alternating current voltage is measured; and whether an alternating current interlarding fault exists in the direct current system is judged according to the magnitude of the to-be-measured resistor alternating current voltage.

Description

technical field [0001] The invention relates to a fault detection circuit, in particular to an AC intrusion and grounding fault detection circuit of a DC system of a substation and a method for checking the AC intrusion and grounding fault detection circuit of the DC system of a substation. The field of the present invention is substation fault detection circuit. Background technique [0002] The substation DC system is an important power system in the substation, which plays a vital role in ensuring the safe and stable operation of the substation. Therefore, the power supply reliability of the DC system directly affects the operation safety of the entire substation and even the power grid. With the continuous development of the power grid and the continuous improvement of the voltage level, higher requirements are placed on the DC system. [0003] The grounding fault of the DC system may cause problems such as malfunctioning of the DC protection outlet circuit and the ref...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the deficiencies of the prior art, the object of the present invention is to provide a fault detection circuit and inspection method for the DC system of a substation. By combining the characteristics of the unbalanced bridge method and the capacitor blocking the direct traffic, the DC system of the substation is solved. The problem that ground fault detection cannot be performed simultaneously with fault detection

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