Transformer neutrality point combination electric device

Abstract

The invention discloses a transformer neutrality point combination electric device comprising a base (1), wherein the base (1) is grounded and provided with an insulating support post (2), and the insulating support post (2) is provided with a horizontal high-voltage arm (8'), and the horizontal high-voltage arm (8') is connected with a transformer neutrality point (N) and provided with a fixed contact (7); the base (1) is also provided with a grounding post (5), the grounding post (5) is provided with a horizontal grounding arm (9') which is sleeved with a grounding sleeve pipe (10), an insulating bushing is arranged between the grounding arm (9') and the grounding sleeve pipe (10), and the grounding sleeve pipe (10) can slide relative to the grounding arm (9'); the high-voltage arm (8') is provided with a high-voltage electrode (8), the grounding arm (9') is provided with a grounding electrode (9), the high-voltage electrode (8) and the grounding arm (9') are coaxial, oppositely arranged and form a protection gap (J), and the grounding sleeve pipe (10) is provided with a division and combination adjusting device. The invention has simple structure and high aggregation degree.

Description

Technical field [0001] The invention relates to the field of power transmission technology, and is a transformer neutral point combined electrical device that combines the functions of each single equipment required by the current 110kV and 220kV transformer neutral points into an integrated device. Background technique [0002] According to the People’s Republic of China Electric Power Industry Standard DL / T620-1997 "Overvoltage Protection and Insulation Coordination for AC Electrical Installations", 110kV and 220kV power grids (hereinafter referred to as grids) are effectively grounded grids, that is, the neutral point of the grid during actual operation The voltage to the ground (that is, the earth) is "0" or close to "0". The neutral point of this type of power grid must be effectively grounded. The neutral point of the power grid is grounded by the neutral point of the transformer in the power grid. In actual operation, the selective grounding operation mode is adopted, that...

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Problems solved by technology

[0005] 2. When this kind of power grid accidentally forms a local ungrounded power grid for some reason, and a single-phase ground fault occurs, under this abnormal working condition, the power grid may generate high power frequency overvoltage, which affects the safety of electrical equipment in the power grid. Therefore, according to the regulations of DL / T620-1997, the neutral point of the ungrounded transformer should be equipped with a rod-shaped air protection gap, also known as a rod gap.

Therefore, the overall weight is large and consumes a lot of porcelain resources

[0013] 3. The longitudinal length of the entire device is long after combination, which is not suitable for indoor and underground stations such as 110kV

[0014] 4. The GW13 series neutral point isolating switch is a double-rotary arm coupling structure, and the contact stability is not ideal.

[0015] 5. When the longitudinal arrangement length of the equipment reaches more than 3.5m, a double-pillar installation structure must be adopted, and the cost of foundation and pillars is high

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