CN2859764Y - Large-capacity on-load capacity regulating power transformer - Google Patents

Abstract

A large-capacity on-load capacity-regulating power transformer belongs to a type of transformer and solves the problem of transformer capacity regulation. It includes a transformer shell, a high-voltage winding and a low-voltage winding installed in the shell; it is characterized in that: the shell is equipped with an on-load capacity regulating switch and its operation control device; the high and low-voltage coil taps are respectively connected to the on-load capacity regulating switch ; The low-voltage winding is composed of two sets of turns, the small turns are wound by one wire, and the large turns are wound by two wires. According to the size of the electric load without cutting off the operating load, the on-load capacity regulating switch can be used to change the winding connection mode to adjust the capacity level; it is a power transformer suitable for rural power grids with a rated capacity of 400kVA and above.

Description

Large-capacity on-load capacity regulating power transformer

Field

The utility model relates to a power transformer, in particular to a transformer with two capacity levels, large and small, and adjustable capacity when loaded.

Background technique

In the current price segment, the rated capacity of traditional capacity-adjusting distribution transformers is only below 400kVA, and its application is limited; capacity-adjusting transformers cannot be charged and adjusted, which affects the reliability of power supply for users and restricts further promotion and use.

Contents of the invention

In order to solve the above problems, the purpose of this utility model is to provide a large-capacity on-load capacity regulating power transformer.

The technical scheme of the utility model is: a large-capacity on-load capacity-regulating power transformer, including a transformer shell, a high-voltage winding and a low-voltage winding installed in the shell; device; the taps of the high and low voltage coils are respectively connected to the on-load capacity regulating switch; the low voltage winding is composed of two sets of turns, the small turns are wound by one wire, and the large turns are wound by two wires .

There are two ways to connect the high-voltage and low-voltage windings controlled by the on-load capacity regulating switch: one is that the high-voltage winding is a delta connection, and the two wires of the large turn of the corresponding low-voltage winding are connected in parallel and connected in series with the small turn. One connection method is the connection method when the transformer has a large capacity; the other is that the high-voltage winding is a star connection, and the two wires of the large turn of the corresponding low-voltage winding are connected in series with the small turn. The method is the connection method when the transformer has a small capacity.

When the capacity is changed from large capacity to small capacity, the number of turns of the low-voltage winding increases, while the high-voltage winding becomes Y-connected, the phase voltage decreases, and the number of turns increases by the same multiple as the voltage decrease, ensuring that the output voltage remains unchanged. When the large capacity is adjusted to a small capacity, due to the increase in the number of turns of the low-voltage winding, the magnetic flux density of the core is greatly reduced, so that the unit loss of the silicon steel sheet is reduced, and the no-load loss and no-load current are correspondingly reduced, achieving the purpose of reducing loss and saving energy. .

The beneficial effect of the utility model is that it can adjust the capacity of the transformer according to the size of the load when the transformer is not powered off, which solves the problem of large no-load loss of the transformer due to the large seasonal load changes of the rural network and the low power consumption period, and is suitable for rated Rural power grids with a capacity of 400kVA and above.

Description of drawings

Below in conjunction with accompanying drawing, the utility model will be further described,

Fig. 1 is the front view of the assembly appearance of the present utility model;

Fig. 2 is the top view of the assembly appearance of the present utility model;

Figure 3 is a schematic diagram of the connection of the winding when the transformer has a large capacity;

Figure 4 is a schematic diagram of the connection of the winding when the transformer has a small capacity;

In the figure: 1. Transformer shell, 2. On-load capacity regulating switch, 3. Operation control device of on-load capacity regulating switch.

Detailed ways

As shown in Figure 1 and 2.

The large-capacity on-load capacity-regulating power transformer includes a transformer housing 1, a high-voltage winding and a low-voltage winding installed in the housing 1;

The taps of the high and low voltage coils are respectively connected to the on-load capacity regulating switch 2; the low voltage winding is composed of two sets of turns, the small turns are formed by a section I of a wire, and the large turns are formed by two wires II and III Segments are wound together.

As shown in Figures 3 and 4, the basic principle of transformer on-load capacity regulation is: the three-phase high-voltage windings of the transformer are connected in a delta (D) when the capacity is large, and connected in a star (Y) when the capacity is small; Sections II and III of the winding are connected in parallel and then connected in series with section I. When the capacity is small, sections I, II, and III are all connected in series. When the capacity is changed from large capacity to small capacity, the number of turns of the low-voltage winding increases, while the high-voltage winding becomes Y-connected, the phase voltage decreases, and the number of turns increases by the same multiple as the voltage decrease, ensuring that the output voltage remains unchanged.

The change of the connection mode of the high-voltage winding, the conversion of the low-voltage winding into parallel and series, and the adjustment of each tap part are all completed by the special on-load capacity regulating switch 2 . The on-load capacity regulating switch is the prior art. When the large capacity is adjusted to a small capacity, due to the increase in the number of turns of the low-voltage winding, the magnetic flux density of the core is greatly reduced, so that the unit loss of the silicon steel sheet is reduced, and the no-load loss and no-load current are correspondingly reduced, achieving the purpose of reducing loss and saving energy. .

Other technologies are the same as prior art.

Claims (1)

1. Large-capacity on-load capacity-regulating power transformer, including a transformer shell, a high-voltage winding and a low-voltage winding installed in the shell; it is characterized in that: the shell is equipped with an on-load capacity regulating switch and its operation control device; the low-voltage The winding is composed of small coils and large coils connected in series. The small coils are wound by one wire, and the large coils are wound by two wires. The taps of the high and low voltage coils are respectively connected to the on-load regulator switch.

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