JP2005197623A - Space-saving power receiving power transformer and single pole type space-saving high voltage power receiving installation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To resolve the problem wherein capacity and weight of a power receiving power transformer used for a high voltage power receiving installation are large, the transformer is too large and redundant and full load loss is enlarged, thus causing a cost rise. <P>SOLUTION: In the high voltage power receiving installation where in a three-phase AC transformer and a balancer are integrated or a single pole type high voltage power receiving installation, a voltage to ground is 115V, harmonics causing false report is restrained, secondary side wiring is reduced and ohmic loss is reduced. Consequently, a light and miniaturized space-saving power transformer is realized, an installation space such as a cubicle is cut, and cost reduction is realized. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

As a result of intensive research aimed at miniaturization of the power transformer of the high-voltage power receiving equipment, the present invention leads to the invention of the space-saving power receiving power transformer and the single-column space-saving high-voltage power receiving equipment.

In the conventional technology, high-voltage power receiving equipment technical guidelines, etc. have installed high-voltage cubicles, etc. indoors and outdoors as receiving substations, but the transformer body is large and space is a problem.
Example See Non-Patent Documents 1 and 2. Transformer Utilization Manual OHM Co., Ltd. October 20, 1995 Toshiba, Hitachi, Mitsubishi Catalog August 2003

Conventional technology

The high-voltage three-phase alternating current is supplied to the high-voltage power supply facility at 6000 V, and this is transformed into a three-phase 200 V and a single-phase 200 V or 100 V by a power receiving transformer. Therefore, a three-phase 200V transformer and a single-phase 200V or 100V transformer are used for the power receiving equipment, both of which are composed of a high voltage primary coil and a low voltage secondary coil.
Although one or two transformers are required depending on the purpose, it is inevitable that the volume, area, weight, and oil amount of the power receiving equipment will increase. In order to prevent an electric shock accident at the time of high / low pressure contact accident, in the conventional three-phase AC transformer, it is determined by the standard that one of the three secondary terminals is grounded.

The conventional method is shown in FIG. FIG. FIG. This will be described in Table 1.
As an example of the same structure, when the load facility capacity is a three-phase power load 30 KW and a single-phase lamp load 37 KVA, a total of 67 KVA, the transformer capacity is selected as shown in Table 1 , and there are several types.

In general, a three-phase power transformer 50KVA and a single-phase transformer 50KVA are used.
The individual power transformer will be described as shown in FIG.
A three-phase AC transformer was used for the three-phase power load, and a single-phase three-wire transformer and a transformer for each power system or purpose were installed for the single-phase load. If both transformers have a load power factor of 100%, they can be used at the rated capacity, but they are not flexible.

As shown in Fig.-2, explanation will be given on the power transformer for moving lights.
When the phase sequence in the star connection on the three-phase secondary side is R, S, T, there are winding coils between the phases, and the winding between R and S is a single-phase three-wire winding for electric lamps. For example, one phase of a three-phase power transformer is 10 KVA, and three times that is the capacity when the rated capacity is 30 KVA. A single-phase three-wire transformer 30KVA is connected between S and is used for electric lamps. The rated capacity is 30KVA for power and 40KVA for 30 + 10 for electric lamps.

A V-type wired power transformer will be described as shown in FIG.
R. Between S and S. Combining two single-phase transformers between T and connecting them to V type is convenient because it can be used with power and electric lamps. The S side advances and becomes a power factor, and power factor improvement is required.

In the conventional system, which has a ground voltage of 173 V and requires 4 to 6 wires, the power transformer is heavy and requires a large space.

Conventionally, a high-voltage power receiving facility has been installed with a substation room, high-pressure cubicle, etc., and a power transformer is installed inside it, converting high-voltage electricity into low-voltage electricity. Divided for each system, the capacity and quantity of power transformers are increasing. From the viewpoint of safety of each power transformer, it is excessive, excessive, and the design has increased no-load loss. Also, the installation space is wide. The ground voltage is 200V, which is widely required, and it is dangerous, the problem of false alarm of harmonic disturbance, the risk of the inspector due to overcrowding of the cubicle internal equipment is high, and the power three-phase three-wire 200V three The core cable and the single-phase three-wire 200V and 100V three-core cables for electric lamps were necessary, and the wiring cost was also expensive.

A three-phase AC power transformer and a single-winding transformer are integrated, and the neutral point of the secondary winding of the three-phase transformer is grounded and connected between different terminals of the single-winding transformer. A single-phase power supply can be taken out from the wire taken out from AA to make an AA power supply.

If the three-phase AC transformer is a neutral point grounding type, the transformer can be reduced, and it can be reduced to a light and small space-saving power supply transformer. If the above formula is used, it becomes a space-saving single-column high-voltage power receiving facility, which can contribute to cost reduction.

BEST MODE FOR CARRYING OUT THE INVENTION Example

As shown in FIG. 4 or Table 1, in the present invention, as a result of intensive research aimed at miniaturization of a high-voltage power receiving power transformer, (1) a three-phase AC power transformer and a single-winding transformer are integrated.
(2) Connect the different terminals of the secondary winding of the three-phase AC power transformer with a single-winding transformer (hereinafter referred to as a balancer). Take out,
(3) As shown in FIG. 5, the balance of the balancer is reduced to one-tenth to one-fifteenth that of the three-phase AC transformer. It has been found that it can be realized, and has led to the invention of a space-saving power transformer. The main feature of the transformer of the present invention is that it is small, light, and requires little storage and installation space. It can be installed in substations, cubicles, pillars, and indoors and outdoors. ,
(4) As shown in FIG. 6, a space-saving high-voltage power receiving facility is a more compact pole-mounted high-voltage power receiving facility, which does not take up an installation place where one or two transformers are set on the pole with one power pole. It is a space-saving high-voltage power receiving facility. Traditionally, transformers have been rated for rated capacity, configuration, quantity, etc. in consideration of demand rate, load rate, inequality rate, unbalance rate, etc. based on the load equipment. Easily becoming an excessive transformer capacity has become obvious, making it possible to save energy by making this an appropriate capacity.

FIG. 4 of the present invention is a high-voltage power receiving facility with a space-saving three-phase power transformer as shown in FIG. 5, but the phase sequence will be described as an example (hereinafter referred to as a lighting power supply wiring system). S. T. R. of the low-voltage secondary winding coil of the three-phase power transformer. S. T. T. et al. Connect the neutral point of the cable to the ground. S. A single-winding transformer (hereinafter referred to as balancer, turns ratio 1: 1, 1/10 to 1/15 capacity of main power transformer) is connected, secondary voltage three-phase 200v, single-phase three-wire 200v / 100v easily It is possible to take.

In the conventional one-wire grounding system, the ground voltage 173v is safe at a ground voltage of 115V. In the one-wire grounding conventional system, the charging current including harmonics is a vector sum of (IAC + IBC), and the grounding current is doubled and insulated. The frequency of false alarms such as monitoring devices increases. Further, in the lighting service wiring system of the present invention, the charging current including harmonics due to the ground capacitance can be canceled by 90 ° advance current vector (LA + IB + IC = 0) to suppress false alarms.

The main 4-pole switch of the wiring system for lighting of the present invention (3-pole element is for protecting the neutral grounding transformer, 1-pole element is for protecting the balancer). The switch is cut off to protect the transformer and balancer. The balance between the balancer installed between the three-phase 200vRS phases is taken out from the middle and outer lines of the balancer, and 100V x 2 circuits (for 100V outlet) are taken out and supplied. It may be housed inside or outside the transformer or inside a cubicle or inside a low-voltage distribution board.

Taking the in-service wiring system of the single-post-type high-voltage power receiving facility of the present invention as an example, there is an effect of suppressing the construction cost with no space-based cubicle required or space saving.

The main wiring of the present invention is drawn into the distribution board with only one three-core cable, the three-pole switch is for three-phase 200v power load, and the single-phase 200v two-pole switch is illuminated with good load balance from the three-phase side Take for load, R. Supply the balancer power from the S side. The single-phase 100v from the S side is supplied from a two-pole switch dedicated to a 100V outlet with a view to the load balance.

Conventionally, there are various combinations of transformers for high-voltage power receiving equipment, such as single-phase, three-phase, same-capacity V, different-capacity V-connections, and delta star-type service types. A conventional standard transformer or a high-efficiency top runner transformer may be used.

Even when using a conventional standard oil transformer, it is better to use a high-efficiency top runner transformer for the balancer, with no load loss 1/4 and low power loss.

According to the balancer balance determination method of the present invention, the unbalanced value of both outer lines can be determined by the rotation direction of the disk-type single-phase watt-hour meter (rotating in the direction with a larger current value) and the middle line ammeter.

Individual connection explanatory drawing of a conventional three-phase three-wire power transformer and a single-phase three-wire lamp transformer. Connection diagram of a transformer combined with a conventional transformer and integrated with a lamp. Explanatory drawing of the connection of a transformer that is operated by a V connection of two conventional single-phase transformers and is in service. The connection explanatory drawing of the neutral point grounding type space-saving type | mold power lamp service power transformer of this invention. Connection diagram of balancer of the present invention BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an external view of a space-saving single-column high-voltage power receiving facility according to the present invention.

Table 1

Comparison table of conventional type and the present invention.

Explanation of symbols

Claims (2)

(1) A space-saving power transformer for power reception characterized by integrating a three-phase AC transformer and a single-phase single-winding transformer.
(2) The neutral point of the secondary winding of the three-phase AC transformer is grounded, and different terminals of the secondary winding are connected by a single-winding transformer. A space-saving power transformer for receiving power, characterized by taking out single-phase alternating current, which is half of phase alternating current.
(3) A space-saving power receiving power transformer, wherein the electric capacity of the single-winding transformer is 1/10 to 1/15 of the electric capacity of the three-phase AC transformer. A space-saving high-voltage power receiving facility in which the space-saving power receiving power transformer according to claim 1 is a single pillar type and installed on a pillar.

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