A voltage equalization method for the main grounding grid of a substation

Abstract

The invention discloses a voltage-sharing method for a main grounding network of a transformer station, and the method is used for solving a problem of grounding safety. The method is characterized in that the method comprises the following steps: (1), measuring the soil resistivity of the transformer station, and carrying out the structural design of a grounding network; (2), calculating the distribution condition of ground potential rise, and adding a grounding electrode at a corner of the grounding network with the most uneven distribution of ground potential rise; (3), determining the parameter of the grounding electrode, enabling the grounding electrode to be connected to the grounding network, and then carrying out the new calculation till a contact voltage and a step voltage reach set values. According to the invention, the corner of the grounding network is provided with the grounding electrode, and the grounding electrode can effectively reduce the distribution unevenness of the ground potential, thereby effectively reducing the contact voltage and the step voltage, and improving the safety of the grounding network.

Description

technical field [0001] The invention relates to the technical field of a voltage equalization method for a grounding grid, in particular to a voltage equalization method for a main grounding grid of a substation. Background technique [0002] A good grounding system is a necessary condition to ensure the safe operation of substations. According to relevant domestic grounding standards, the power frequency grounding resistance of the substation grounding grid should meet Among them, I is the grounding current flowing into the grounding grid. When the grounding resistance of the main grounding network satisfies this formula, the ground potential rise of the substation will not exceed 2kV, which can generally guarantee the safety of equipment and personal. [0003] With the development of economy and society, the scale of power system is expanding day by day, and the ground fault current of voltage busbars at all levels in substations is increasing year by year. When a sing...

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Problems solved by technology

[0014] At present, substations rarely set up living areas, and there is no problem of external potential; substations with problems with the grounding grid are generally 110kV and above substations, the voltage level of the low-voltage side is generally higher than 10kV, and there are many outgoing lines on the low-voltage side, so metal oxide arresters Generally, the safety can be guaranteed; therefore, for the safety assessment of the grounding grid of the substation, the key to whether the allowable value of the grounding resistance can be increased is to find an economical and efficient way to solve the problem of uneven distribution of the grounding potential, thereby reducing the Touch voltage, step voltage, meet safety requirements

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