Tapping switch for load voltage-regulating transformer and voltage-regulating transformer using the same

Abstract

The invention discloses a tapping switch of an on-load regulating transformer. The tapping switch comprises a single tapping switch controller connected with a voltage regulation controller, a first two-way switch with one end being connected with the single tapping switch controller and the other end being connected with the voltage regulation controller through a first filter, a second two-way switch with one end being connected with the single tapping switch controller and the other end being connected with the voltage regulation controller through the first filter and the first filter connected among the first two way switch, the second two-way switch and the voltage regulation controller, wherein, the first two-way switch and the second two-way switch are mutually connected, so as tobe used for controlling the change of the number of windings of the primary side or the secondary side of the voltage regulation controller along with the change of the switching condition of the first two-way switch and the second two-way switch. The tapping switch can realize the continuous and quick voltage regulation without harmonic waves, electric arcs and actuating mechanisms, and the tapping switch has few electronic switches, thereby having the advantages of simple structure, easy control and low cost.

Description

technical field [0001] The invention relates to the field of transformers, in particular to a tap changer of a voltage regulating transformer and a voltage regulating transformer including the tap changer of the voltage regulating transformer. Background technique [0002] For distribution transformers in operation, due to changes in the primary side voltage (grid voltage), load size and nature, the secondary side voltage may have large changes. my country's distribution transformers cover voltage levels below 35kV. In order to maintain the load voltage within the specified range (±5% U N ), to ensure the normal needs of electrical equipment, the distribution transformer must be voltage-regulated. At present, the distribution transformers used in rural power grids basically adopt the no-load voltage regulation method. No-load voltage regulation requires that the tap changer must be disconnected from the power grid on both the primary side and the secondary side of the dist...

AI Technical Summary

Problems solved by technology

[0003] (1) It cannot automatically adjust the on-load voltage with the change of the grid voltage, and the DC resistance must be measured after the tap changer is switched off;

[0004] (2) The voltage adjustment range is generally 3 gears, and the actual fluctuation range is relatively large;

[0005] (3) Since it cannot be adjusted in real time, when the voltage is too high or too low, it will seriously damage the electrical equipment;

[0006] (4) The automatic compensation capacitor, because of the voltage protection, can hardly be used during peak and valley periods

In this scheme, the third winding of the main transformer T1 is used to generate an additional voltage, and the additional voltage is connected to the main power supply in series through the electronic switch S1 and the auxiliary transformer T2. The shortcoming of this scheme is that the thyristor phase-shift control generates harmonics

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