JPS60208814A - stationary induction appliance - Google Patents

Abstract

PURPOSE:To adapt to different incoming voltages whose ratio is not integer times, by star-connecting three phases each consisting of a plural of wires which are connected in series, or by delta-connecting three phases which are connected in parallel, as a primary winding. CONSTITUTION:When the incoming voltages is V, three phases each consisting of a plural of wires which are connected in series, are star-connected. On the contrary, when the incoming voltage is V/2X3<1/2>m, three phases each consisting of the plural of wires which are connected in parallel, are delta-connected. Since the voltage per one turn is the same in both the case, by only changing the connection of the primary winding while employing the same iron core, this apparatus can be adapted to both of the incoming voltage V and V/2X3<1/2>m.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a stationary induction appliance with a novel structure capable of receiving different voltages.

[Background of the invention]

Conventionally, the following method has been used for a stationary induction electric device that initially receives power at voltage v1 and is planned to receive power at voltage v2 in the future. In other words, taking a transformer as an example, (i) As shown in Figure 1(a), initially the receiving voltage is V
, and in the future (b), replace it with a transformer 1b whose receiving voltage is v2.

(11) As shown in Figure 2, the receiving voltage of the transformer is vl
If the incoming voltage becomes V2 in the future, a transformer 1b' is installed on the primary side of this transformer to convert ■2 to ■1.

(iii) When the initial power reception voltage is vl and becomes v2 in the future, V
If the ratio of 2 and vI is an integer (i.e., for example, 22 kV is initially received and 66 kV is received in the future), then Fig. 3(a)
, As shown in (b), the primary winding of the transformer was divided into three blocks 2a, 2bt and 2c, and initially the three blocks were connected in parallel to receive power, and in the future the power was 66kV. In this case, three blocks can be connected in series to receive power.

etc. were taken. However, method (1) eliminates the need for the transformer that was originally used, so if it is known that the receiving voltage will change in the future, this will result in a very wasted investment. In method (11), if the receiving voltage changes in the future, it is necessary to have a transformation ratio of V, /V, and at the same time, it is necessary to secure a place to install the transformer, which is economical. I can't say that. In the case of (City)'s method, one transformer can be used both initially and in the future, so (i)
Although it is more economical than (it), there is a restriction that the voltage is an integer multiple such as 66kV and 22kV, so for example, the ratio is approximately 1:22kV at the beginning and 70kV in the future.
If the ratio is not an integral multiple, such as 3.46, there is a drawback that the winding cannot be constructed.

[Purpose of the invention]

An object of the present invention is to provide a stationary induction electric appliance with a novel winding configuration that can cope with a receiving voltage whose ratio is not an integral multiple, such as an initial 22'kV receiving voltage of 77kV in the future.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, details of a stationary induction electric appliance having a winding structure will be described with reference to figures showing embodiments of the present invention.

FIG. 4 shows an embodiment of the present invention, and only the primary winding composed of an even number of windings is shown (to simplify the explanation, the figure shows two windings for each phase). As shown in FIG. 4(a), when the receiving voltage is V, an even number of wires are connected in series to form a negative phase (eg, U phase). If the number of turns of one strand of the even number of strands at this time is T, the total number of turns for one phase is 2 mT since they are connected in series.

If these are connected in a star shape, the voltage per turn is e.

Next, the receiving voltage is v/2.5. , when m, the fourth
As shown in Figure (b), one phase (for example, U phase) is created by connecting an even number (2 m) of wires in parallel. At this time, the number of turns of the negative phase is T. When this is triangularly connected, the voltage e2 per -turn becomes (l,:Q2...(3) from equations (1) and (2), so with the same iron core, the -th winding It can be used for both receiving voltage V and v/2/im by simply changing the wiring.

When the nominal voltage is 77kV (7), 22.22kv, 11
．． It can receive voltages such as 11kV, so the nominal voltage is 22kV.
.

It will be possible to receive electricity such as 11kV.

Furthermore, if the initial voltage is 22kV and the future value is 77kV, if you connect the wires as shown in Figure 4, V/2/im=22
(However, from m=1, 22=v/2Ld,", V=76.21kV, and when 77kV is received, the secondary voltage will rise by about 1%. Therefore, we want the secondary voltage to be the same in the future. In this case, as shown in Figure 5, if a tap 6 is provided in the secondary winding (for simplicity, only one phase is described), the secondary voltage will be constant, so there will be no impact on the load. Do not cause any hindrance.

〔Effect of the invention〕

According to the present invention, a stationary induction electric appliance with a novel winding configuration that can cope with a received voltage whose ratio is not an integral multiple is provided.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are conventional explanatory diagrams, Figures 4, and 5.
The figure is an explanatory diagram of an embodiment of the present invention. la, lb-transformer, 2 a, 2 b, 2 c
, 5-1st zrh (b) V, E diagram ζV

Claims (1)

[Claims] 1. In a three-phase stationary induction electric appliance having an iron core and a winding wound around the iron core, the primary winding is composed of an even number of wires for both phases, and the receiving voltage is V. When the even number of the wires are connected in series to form one phase, and the three phases are connected in a star shape, when the receiving voltage is vl2 to -m, the even number of the wires are connected in parallel. to create a phase,
A stationary induction electric appliance characterized by triangular connection of three phases. 2. A stationary induction electric appliance according to claim 1, characterized in that it is intended to receive power at an initial nominal voltage of V and a future nominal voltage of 25 V. 3. In claim 1 or 2. A stationary induction electric appliance characterized by having a tap for the secondary winding.