A transformer-integrated arc-free on-load tap-changer

Abstract

The invention discloses a transformer integrated arc-free load-equipped tap switch. The transformer integrated arc-free load-equipped tap switch comprises a fixed contact connected with a transformer tapping, a moving contact D1 connected with a transformer outlet terminal and driven by a motor, and a controlling circuit, wherein the moving contact D1 comprises a first bilateral switch branch of which one end is connected with the outlet terminal, a direct connection contact terminal and a second bilateral switch branch; both of the first switch branch and the second bilateral switch branch are formed by adopting the structure that two power electronic switches are connected in a combined manner, then, a cushion circuits is connected with the two power electronic switches in parallel, and a fuse is connected in series. The bilateral switches and sequential control on triggering of the bilateral switches are adopted to realize arc-free switching of load-equipped tap switches, an accident during failure of the bilateral switches is prevented, reliable power supply is ensured for the controlling circuit, and the transformer integrated arc-free load-equipped tap switch is simple in structure and reliable in working.

Description

technical field [0001] The invention relates to the technical field of transformer voltage regulation, and more specifically relates to a transformer integrated arc-free on-load tap changer. Background technique [0002] In the prior art, for a distribution transformer in operation, due to changes in the primary side voltage, load size and nature, the secondary side voltage may have a large change. my country's distribution transformers cover a voltage level below 35kV. In order to maintain the load voltage within the specified range and ensure the normal needs of electrical equipment, the distribution transformer must be adjusted. [0003] The basic principle of transformer on-load voltage regulation is to draw several taps from the coil on one side of the transformer, generally the high-voltage side, and switch from one tap to the other through the on-load tap changer without cutting off the load current. A tap to change the number of effective turns to adjust the voltage...

AI Technical Summary

Problems solved by technology

[0008] The problems existing in the existing technology are: the mechanical tap changer generates an arc during the tap switching process, causing contact ablation; when the vacuum tap changer adopts a fixed structure, the off-state vacuum switch is always under voltage, and it needs to be designed according to the system voltage. When the mobile structure is adopted, due to the slow opening and closing time of the vacuum switch, the moving speed of the moving contact needs to be coordinated with it, which is difficult to control; and the above-mentioned tap changers need transition resistance, which increases the loss

This solution still has an arcing process during the switching process, and cannot realize arc-free on-load tap-changers

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