JPS59188907A - Reactor - Google Patents

Abstract

PURPOSE:To facilitate regulation of reactance of a reactor by simplifying constitution, and to contrive to form the reactor in a small type by a method wherein a secondary winding is provided to a core leg wound with a main winding to make reactance variably. CONSTITUTION:A secondary winding 26 is provided to the main winding 21 of a reactor 2, a reactor 5 is connected to the winding 26 through switches 28, 29, and moreover a switch 27 is connected as to enable to short-circuit between the terminals of the winding 26. Reactance of the winding 26 can be changed according to the opened and closed conditions of the switches 27-29, and moreover reactance of the winding 21 can be changed according thereto. Namely, reactance can be set to the minimum value by opening the switches 27-29, can be set to the middle value by closing the switches 28, 29 and opening the switch 27, and can be set to the maximum value by closing the switch 27.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power grid reactor, and more particularly to a reactor that can adjust the reactance of the reactor.

Conventionally, a reactor (shunt reactor) has been used, for example, for the purpose of compensating the charging current of a power transmission line, but the reactor is always connected to the power transmission line and is used continuously. For example, the transformers used in 500 km' class substations are autotransformers from the point of view of economy, and they are manufactured as single-phase transformers and connected in a Y-Y-Δ manner in a three-phase transformer. It is used as a bank. It is common practice to connect a capacitor or an accelerator to the tertiary terminal of each phase to adjust the reactive power.

FIG. 1 is a one-phase wiring diagram showing an example of a conventional example in which a reactor is connected to this type of autotransformer. In FIG. 1, an autotransformer 1 has a series winding 11, a shunt winding 12, and a tap winding 1'3 connected in series, and a series winding 11 connected to a line terminal (symbol U). ) side, while the tap winding 13 is connected to the neutral point (code 0 side), and the connection point between the series winding 11 and the shunt winding 12 is formed in contact with the secondary line terminal (code U) side. A tertiary winding 14 is disposed with respect to the shunt winding 12, an excitation winding 15 is connected in parallel with the tertiary winding 14, and the tag winding i13 is excited by this excitation winding 15. The terminals (symbols α, d) of this tertiary winding 14 are connected to the winding 21 of the VC beam axle 2.

With this structure, the secondary voltage can be kept constant despite fluctuations in the negative voltage by switching the tag of the tap winding shaft 13. Further, by switching the polarity of the tap winding 13, the number of switching taps can be doubled. By the way, for example, the primary maximum voltage is 527.7/v' kV rated - secondary voltage
500/V'T k V lowest voltage +77.77-
7 kV secondary rated voltage 275/VTI kV tertiary rated voltage? ? In the case of a kV autotransformer, the -th maximum voltage is 527
．． When the voltage is 7/V', the neutral point (0 point) is connected to terminal A of the tap winding 13 (the number of tap turns is zero), and the minimum primary voltage of the trench is 477.7/V'3kV. In this case, the neutral point (0 point) is connected to the terminal H (the number of taps is maximum) of the tap winding 13.

For the tertiary voltage, the turn ratio of the shunt winding 12 and the tertiary winding 14 is constant, and the tap winding 13 is provided on the neutral point (0 point) side of the autotransformer 1, so the above In the case of the rated voltage example, the fluctuation of the -order voltage is → - (tance) 5
．． When the voltage is 5%, the tertiary voltage fluctuates by +12.3918, and when the negative voltage fluctuates by -4.5%, the tertiary voltage fluctuates by a factor of -9.9, and the tertiary winding 14 and the terminal voltage of the accelerator 2 also fluctuates in the same way. Therefore, if reactor 2 has a fixed reactance, the reactor capacity will be +11 on average.
There will be an increase or decrease in chi. Therefore, if the required capacity of reactor 2 is rated at the lowest voltage, an overvoltage withstand capacity of about 23% is required, and if the required capacity of the reactor is rated at the highest voltage, the capacity will be insufficient at the lowest voltage. (The result is that the required capacity cannot be loaded.)

For this reason, as mentioned above, it is common practice to adjust the reactance of the actuator 2.The following two methods are typical for changing the reactance of this type of actuator. There is a way. That is, (1) Adjustment is made by changing the number of turns of the winding.

■ Install a control (DC) winding to flow DC and change the path of magnetic flux to adjust reactance.

There are two methods. However, all of these methods have the following problems.

First, a conventional example in which the reactance is adjusted by changing the number of turns of the winding (2) will be explained based on FIGS. 2 and 3.

That is, first of all, in the one shown in FIG. 2, a tap 3 is provided on the winding 21 of the reactor 2, and the number of turns is changed by switching the tap with a tap changer 4.

In this case, it is necessary to reduce the delay current flowing through the reactor when changing the tap, so the tap changer 4
The disadvantage is that it becomes complicated.

Next, the system shown in FIG. 3 is a system in which a tap 3 is provided on the winding 21 of the reactor 2, and the number of turns is changed by switching the tap via switches 4α, 4h such as a circuit breaker or a silice switch. , for example, switch 4α is turned on, while switch 4b is turned off and tap 3b is turned on.
When switching from the energized state to the tap 3c, the switch 4α is turned off and the switch 4b is turned on at the same time to switch from the tap 3b to the tap 3C.

In addition, the switch 4b and tap 3c are energized (switch 4
When switching the tap to 3d on the upper side in the figure while α is in the OFF state, connect the terminal of switch 4a to tap 3d as shown by the dotted line in the figure.
Then, at the same time as switch 4b is turned OFF, switch 4b is turned OFF.
By turning on α, switching from tap 3c to tap 3d is performed.

However, in the case shown in Fig. 3, with VC, unless the switches 4α and 4b are switched quickly and reliably, both switches 4a and 4b will turn ON or OFF, causing a short A) between the taps. In order to avoid the possibility that the current may stop flowing between the two taps (for example, JH, - in the above operation) At 4th, tap 3c and 3
When d is shorted, VC is.

3c and 3d), it is necessary to insert a resistor straddling handle (not shown) for one fill of short circuit current.

Therefore, the resistor or accelerator for short circuit current suppression is
If the VC load current is provided directly between the taps, there is a problem that a larger one must be used because these VC load currents constantly flow. On the other hand, there is a method of connecting a resistor or accelerator for inhibiting only when switching, but this requires a new switch, resulting in a complicated structure and operation, and a large size. There are problems like this.

Therefore, the method of adjusting the reactance by changing the number of turns of the winding has the problem that the device becomes large and complicated.

Next, a conventional example in which the reactance is adjusted by providing the control winding (2) and flowing the @ flow will be explained with reference to FIG. That is, in the case shown in FIG. 4, the gapped core legs 22α, 22α of the core 22 of the reactor 2 are wound with 1 m of primary (AC) windings 21a, 21a, and the other core legs 22bK&-1 are wound. A tit (direct current) winding 21M is wound, and a direct current is passed through this control winding 21M to generate a direct current magnetic flux 2.
By changing 4.25, the reactance is changed. In addition, the code|symbol 23 is the winding 21a,
The alternating current magnetic flux is 21αKj.

However, when the control winding 21b is provided as shown in FIG. 4, there are problems such as the core and winding dimensions require a relatively large force, and a separate DC power source is required, and the structure is generally complex. There were problems such as the large size.

The present invention has been made in view of the above points, and an object of the present invention is to provide a reactor whose reactance can be easily adjusted with a simple configuration.

° In order to achieve this objective, the present invention provides a secondary winding in the reactor, connects the load reactor to the secondary winding, or directly shorts the load reactor, or connects the load reactor to the secondary winding. The reactance of the reactor body can be adjusted by changing the reactance of the reactor by switching the taps.

Next, embodiments of the present invention will be explained based on FIGS. 5 to 11, and the same reference numerals as in FIGS. 1 to 4 above indicate products equivalent to these. from,
Detailed explanations of these will be omitted.

First, what is shown in FIG. 5 is a reactor 2 according to the first embodiment of the present invention.A secondary winding 26 is provided on the main winding 21 of this reactor 2. A switch 27 is connected to connect the reactor 5 via switches 28 and 29, and to short-circuit its secondary winding terminals.

The reactance of the secondary winding 26 is changed by opening and closing the switches 27, 28 and 29, and the parentheses change the reactance of the main winding 1.
121 reactance can be changed; (1) When switches 27, 28 and 29 are opened, the reactance becomes the minimum value (secondary winding 26 is open).

(7) If f28.29 is closed and the switch 27 is opened, the reactance becomes an intermediate value (the state in which the load reactance 5 is connected to the secondary winding 26).

■ If switch 27 is closed, the reactance is maximum (
The secondary winding 26 experiences a short circuit condition 9.

In this way, the reactance ef of the reactor 2 can be controlled by the open/close states of the switches 27, 28 and 29.

Next, FIGS. 6 and 7 show second and third embodiments of the present invention. In the second embodiment shown in FIG. 6, the secondary winding edge 26f of the reactor 2: the switch 27 The structure is such that the reactance is changed by opening or shorting the circuit. In addition, in the third embodiment shown in FIG. 7, the secondary winding 2 of the reactor 2
6 to the load reactor 5 via switches 28 and 29
The reactance of the reactor 2 is changed by connecting or opening the actuator 5 which is loaded by opening and closing the switches 28 and 29.

Next, FIG. 8 shows a fourth embodiment of the present invention,
The tap changer 51 of the load reactor 5 having a tap is connected to the reactor 2 through the switches 28 and 29'ff:
The configuration is such that the reactance of the reactor 2 is changed by connecting it to the secondary winding 26 of the reactor 2 and switching the tag of the load reactor 5.

Next, the iron core 22 and the winding wire (
Main winding 21. The arrangement relationship with the secondary winding 26) will be explained. In the case of the third embodiment shown in FIG. 7 described above, the impedance between the main winding 21 and the secondary winding 26 of the reactor 2 may be relatively small, so the impedance shown in FIG. Thus, a low impedance winding arrangement may be used in which the secondary winding 26 is wound around the iron core 22 and the main winding 21 is wound around the outer periphery of the secondary winding 26.

In addition, as in the first embodiment shown in FIG. 5, the second embodiment shown in FIG. 6, and the fourth embodiment shown in FIG.
When short-circuiting the secondary winding 26 of the It is preferable to use a high impedance winding arrangement such as that placed above or below 21, or in the center.

As is clear from the above explanation, the glue accelerator 2 of the present invention
In this case, the load reactor 5 is connected or directly short-circuited with the secondary winding 26 provided, or the tap provided on the load reactor 5 connected to the secondary winding 26 is switched to adjust the main body actance of the reactor 2. As a result, various effects as described below can be achieved.

(,)　Reactance can be easily adjusted.

(b) If the current is constant, a capacitive force proportional to the voltage can be obtained. Particularly when used as a shunt reactor, adjusting the reactance to be proportional to the voltage has the effect of requiring less capacitance change, as shown in Table 1, compared to the case where the reactance is constant.

(Table 1) (1) As shown in Figure 4, since a control (DC) winding is provided to adjust the reactance, and a separate core leg is provided for winding the acdle wire, the core force (larger However, according to the present invention, the size of the reactor is small and a separate power source (DC) is not required.

(d)! By setting the voltage of the secondary winding ffiJ+26 of the j-acdle to an appropriate value (for example, 22 km' or 22 kV or less), the circuit breakers substituted for switches 27, 28, and 29 are economical (as shown in Fig. 2 or 3). In the conventional example, switch 4 is for example 77km';
The 'switches 27, 28 and 29 used in the present invention are two
It may be rated at 2 kV or 22 kV or less, and the lower the voltage, the more economically advantageous it is.

Many other effects can be obtained.

[Brief explanation of drawings]

Figure 1 is a connection diagram showing the connection for one phase of a conventional auto-transformer axle, Figures 2 and 3 are connection diagrams for one phase of a conventional axle, and Figure 4 is a diagram showing the connection for one phase of a conventional autotransformer axle. 5 to 8 are side views showing the arrangement relationship between the iron core and the winding of a reactor with control winding, and FIGS. 9 through 11 are side sectional views showing examples of the winding arrangement of the reactor shown in FIGS. 5 through 8. 2 is a reactor, 21 is a reactor main winding, 221-t
Reak!・Le iron core, 2641 reactor secondary winding, 27
, 28 and 29 are switches, 5 is a load reactor, and 51 is a tap changer. Patent Applicant Figure 1 Figure 1,) Figure 5 Figure 2 Figure 3 a Figure 4 1b Figure 6 Figure 7 26 Section 8 2G Dod Figure 9 Figure 11 Figure 10 Figure 1 (

Claims (4)

[Claims] (1) A reactor comprising a main winding wound around at least one core leg, characterized in that a secondary winding is provided on the core leg and the actance of the secondary winding is variable. Tosururi Akudol. (2) The glue actance according to claim 1, characterized in that the adjustment of the glue actance of the secondary winding is performed by a switch provided between both terminals of the secondary winding. (3) The glide actuator according to claim 1, wherein the glide actance of the secondary winding is adjusted by a load reactor provided via a switch between both terminals of the secondary winding. (4) The load reactor according to claim 3, wherein the load reactor is equipped with a tap changer.