CN204810154U - Four posts three -phase compensation formula low pressure voltage regulator unshakable in one's determination - Google Patents

Abstract

The utility model provides a four posts three -phase compensation formula low pressure voltage regulator unshakable in one's determination comprises correction transformer and powerstat, and the correction transformer adopts four posts of three -phase structure unshakable in one's determination, three posts of powerstat adoption three -phase structure unshakable in one's determination, wherein, the secondary winding of correction transformer establishes ties in distribution lines, and the primary winding of correction transformer and powerstat tap are connected. Because the correction transformer has adopted four post iron core transformers of three -phase, compensate effectual, the zero sequence loss is little, can reduce the whole volume and the weight of product widely, has reduced manufacturing, operation, cost of transportation effectively, the application region is more extensive.

Description

Four-column core three-phase compensation low voltage regulator

technical field

The utility model belongs to the technical field of power system equipment, and relates to a voltage regulator, in particular to a three-phase compensation type low-voltage voltage regulator of a power system.

Background technique

With the rapid development of my country's economy, the scale of grid electricity consumption continues to grow. Although the power supply companies are actively taking various measures, the rapidly increasing electricity consumption is still far from the current grid power supply and grid structure. The low voltage problem of the power grid caused by overloading is extremely serious, and the phenomenon of low voltage complaints is extremely common. What measures to take to solve the current grid low voltage problem is imminent.

At present, the commonly used power grid low voltage control measures are as follows: (1) install reactive power compensator to boost the voltage; (2) install autotransformer to boost the voltage; (3) increase the output voltage of the distribution transformer in the station area to boost; ) to extend the 10kV line and add a distribution transformer to boost the voltage; (5) to install a low-voltage line compensating voltage regulator to boost the voltage.

However, the methods described in (1)-(4) all have certain defects: although the reactive power compensator can reduce the apparent current, reduce the voltage drop of the line, and indirectly achieve the purpose of boosting the power grid, it is affected by the power factor of the low-voltage line It is relatively large and has limitations; through the direct step-up of the autotransformer, under the same capacity, the device has many consumables, heavy weight, and large volume, which is not only high in cost, but also greatly increases its installation, transportation and maintenance costs due to its large weight; through Raising the output voltage of the distribution transformer in the station area can solve the low voltage problem of users near the station area, but on the other hand, it will easily lead to a higher voltage at the head end of the power grid, which cannot solve the low voltage problem caused by the too long power supply radius; the extension of 10kV is adopted Lines, the method of adding distribution transformers, of course, can solve the problem of low voltage, but the cost will be very high.

Practice has proved that for areas where 400V lines are laid longer and 10kV lines are not easily extended, it is a reasonable choice to install low-voltage line compensation voltage regulators.

Due to the large zero-sequence loss of the core of the three-phase three-column core transformer, the commonly used compensating voltage regulators currently use three-phase group transformers (single-phase transformer groups), which are composed of three single-phase compensating voltage regulators. Its magnetic circuit consists of three sets (6) of independent iron cores, which are independent of each other on the magnetic circuit and are not related to each other (see the schematic diagram of the magnetic circuit in Figure 1, and its working principle is shown in Figure 2).

However, since the single-phase transformer group compensation voltage regulator adopts a three-phase group transformer, the space required is much larger than that of a three-phase transformer, and the manufacturing cost and transportation cost increase a lot. Moreover, the no-load loss and load loss are larger than those of a single three-phase transformer, which also increases the operating cost.

Utility model content

The utility model provides a four-column iron core three-phase compensation type low-voltage voltage regulator to avoid the disadvantages of the above-mentioned prior art, so as to reduce manufacturing and operating costs and improve electrical reliability.

The utility model adopts the following technical scheme: a four-column iron core three-phase compensation type low-voltage voltage regulator, which is composed of a compensation transformer and a voltage regulating transformer, the compensation transformer adopts a three-phase four-column iron core structure, and the voltage regulating transformer adopts a three-phase three-column iron core structure;

Among them, the secondary winding of the compensation transformer is connected in series in the power distribution line, and the primary winding of the compensation transformer is connected to the tap of the voltage regulating transformer;

The input end of the four-column core three-phase compensated low-voltage voltage regulator is provided with a circuit breaker, and the output end is provided with a second contactor.

Further, the four-column core three-phase compensation low-voltage voltage regulator is further provided with a first contactor, and the first contactor is bridged and connected in parallel with the circuit breaker and the second contactor.

The utility model relates to a four-column iron core three-phase compensation type low-voltage voltage regulator. The compensation transformer adopts a three-phase four-column iron core transformer, which has good compensation effect and low zero-sequence loss, and can greatly reduce the overall volume and weight of the product. The cost of manufacture, operation and transportation is effectively reduced, and the application area is wider.

Description of drawings

Figure 1 is a schematic diagram of the magnetic circuit of a three-phase group single-phase transformer;

Figure 2 is a working principle diagram of a single-phase compensated voltage regulator;

Figure 3 is a schematic diagram of the core magnetic circuit of a three-phase four-column transformer;

Figure 4 is a schematic diagram of the working principle of the three-phase compensation voltage regulator.

The symbols shown in the figure and not mentioned below, such as TAa, QF, Km, A-C, a-c, X-Z, x-z, A1, N, n, etc., are conventional power/distribution transformers, circuit breakers, contactors, Schematic symbols of the same name terminal, rated point, power line of the transformer, and other auxiliary symbols such as voltmeters. Although the same symbols represent different components, they are all conventional legend symbols in the field, and do not affect the understanding of the technical solution.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the utility model more clear, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the utility model. Obviously, the described The embodiments are some embodiments of the present utility model, but not all embodiments.

The four-column core three-phase compensated low-voltage voltage regulator of the utility model is composed of a compensating transformer and a voltage regulating transformer, wherein the compensating transformer adopts a three-phase four-column core structure, and the voltage regulating transformer adopts a three-phase three-column core structure.

Referring to Figure 3, since the compensation transformer adopts a three-phase four-column iron core structure, it provides a circuit for the zero-sequence magnetic flux ΦO of the iron core, with small reluctance and large reactance, effectively reducing zero-sequence loss. ΦoA, ΦoB, and ΦoC represent the A, B, and C phase magnetic fluxes of the core, respectively.

Referring to Figure 4, the secondary windings (TBa, TBb, TBc) of the three-phase compensating transformer are respectively connected in series in the power distribution line (i.e. the main line of the power grid), and the primary winding of the compensating transformer and the voltage regulating transformer (TVa, TVb, TVc ) tap connection. By changing the connection position between the primary winding of the compensation transformer and the tap of the voltage regulating transformer, the primary winding of the compensation transformer will input different voltages, and the secondary winding of the compensation transformer will induce a compensation voltage. The specific boost principle can be seen in Figure 2. If the secondary impedance voltage drop of the compensation transformer is not included:

Output voltage Uao=input voltage Uai+compensation voltage UBa.

Since the size of the compensation voltage UBa is provided by the voltage regulating transformer, this boosting method is called "voltage regulation compensation type".

In the utility model, the compensation transformer capacity=voltage compensation percentage*rated load capacity (that is, if the voltage is compensated by 20%, the compensation transformer capacity is 20% of the load capacity), so a smaller capacity can be used to control a larger capacity output.

Taking the TBa phase shown in Figure 4 as an example, the initial position of the connection between the primary winding of the compensation transformer and the tap of the voltage regulating transformer is the rated point A1, and the upward arrow in the figure indicates that the connection position of the joint is upward to increase the output voltage, and downward Arrows indicate that connecting the connector down reduces the output voltage.

As shown in Figure 4, the input end of the power distribution line of the four-column iron core three-phase compensation type low-voltage voltage regulator of the utility model is also provided with a three-phase low-voltage circuit breaker QF, and the output end of the four-column iron core three-phase compensation type low-voltage voltage regulator is provided with There is a three-phase AC second contactor Km2. The three-phase AC first contactor Km1 is bridged and connected in parallel with the circuit breaker QF and the second contactor Km2. Wherein, the first contactor Km1 is a normally open type, and the second contactor Km2 is a normally closed type.

Figure 4 also shows a voltmeter for measurement and control, in which 1v, 2v, and 5v are only schematic symbols and have no practical significance.

Compared with the single-phase transformer group voltage regulator, the three-phase four-column voltage regulator of the utility model also has the advantages of good compensation effect and small zero-sequence loss, and the layout is more reasonable, which can greatly reduce the overall volume and weight of the product. Effectively reduce manufacturing and operating costs. It is especially suitable for users in the remote mountains and border areas due to transportation restrictions.

In the specific application of the above content, technicians may need to make individual adjustments and changes according to specific conditions. The above description of the utility model is only a preferred example, and should not be construed as a limitation to the content of the utility model. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

Claims (2)

1. the compensation low-pressure adjusting depressor of four posts three-phase unshakable in one's determination, is made up of compensator transformer and voltage regulating transformer; It is characterized in that:

Described compensator transformer adopts three-phase and four-pole core construction, and described voltage regulating transformer adopts three-phase three-column core construction;

Wherein, the secondary windings in series of described compensator transformer is in distribution line, and a winding of described compensator transformer is connected with the tap of voltage regulating transformer;

The input of the compensation low-pressure adjusting depressor of four posts three-phase unshakable in one's determination is provided with circuit breaker Q F, and the output of the compensation low-pressure adjusting depressor of four posts three-phase unshakable in one's determination is provided with the second contactor Km2.

2. the compensation low-pressure adjusting depressor of four posts as claimed in claim 1 three-phase unshakable in one's determination, is characterized in that: be also provided with the first contactor Km1, described first contactor Km1 cross-over connection, is connected in parallel on circuit breaker Q F and the second contactor Km2.