JPS58154325A - Current suppressing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a current suppressing device that suppresses short circuits, ground fault currents, and the like.

Recently, electric power systems with ultra-high voltage and large capacity have been proposed, and circuit breakers with large breaking capacity are required to handle the increased short-circuit capacity.

However, with the types of circuit breakers currently in practical use, it is impossible to expect a dramatic increase in the breaking capacity, and it would take a considerable amount of time to develop a new circuit breaker, so the next best option is not possible. Therefore, there is a demand for the development of current suppressing means to reduce the interrupting current.

The present invention has been made in view of the above-mentioned circumstances, and includes winding a primary winding that conducts a line current around an iron core leg, and an impedance circuit that electrically matches Kp with the primary winding through electromagnetic induction. By controlling the coupling relationship between the primary winding and the impedance circuit by opening and closing the circuit breaker,
It is an object of the present invention to provide a current suppressing device that accurately suppresses short circuits, ground fault currents, excitation inrush currents of Yukata devices, etc. The present invention will be described in detail below based on illustrated embodiments. explain.

FIG. 1 shows an embodiment of the present invention, in which five legs υ
~ A pair of divided primary windings 21 and 21B are attached to the legs 11 of the iron core 10 having a feeder, a pair of divided primary windings 21 and 21B are attached to the legs 12, and a pair of divided primary windings 1 and 2 are attached to the legs 13. The next windings comb and ko B are respectively wound, and the m- of each leg 11 to u is connected to the load side line of the power system as a common connection, and the circuit breakers 31, 32, :u are connected between the other ends. and one end is connected to the power line of the power system. In this case, each division 1
Next winding 2M, 21B, Ml.

ffB...? Jmu and JJB are assumed to have the same number of turns so that the line current is equally divided, and are connected to each other so that the magnetic flux due to the shunted current is canceled out for each leg 11 to 13. In addition, the circuit breaker J-Tin is normally closed when suppressing fault current (short circuit, ground fault current), and opened when a fault is detected.

The legs 11, l! of the iron core 10! , All has 2
Next winding λ.

A resistor 41, a reactor 41 B, and a capacitor 41 are connected between both ends of the secondary winding λ of the leg U.
The ti column circuit of 0, that is, the impedance circuit, is connected to the leg 12.
A resistor 42A, a reactor '1. ＼・A series circuit of torque 42B and capacitor 42C is connected, and a resistance lm and a reactor a are connected between both ends of the secondary winding @X of the leg magazine.
The series circuits of No. 11 and No. 430 are connected to each other. The impedance circuit is a glance load, and is used to perform one-phase adjustment to suppress short circuits and ground fault currents, and to adjust the time constant of the system.

Next, one effect will be described. When the purpose is to suppress fault current, the circuit breaker and U-JJ are kept in a closed state.

In this state, the divided primary windings (21k, 21B), (MA
.

The line current is equally divided into Ml), (ffm, JB),
The magnetic flux due to this shunt current is canceled out. Therefore, the coupling between the impedance circuit and the primary winding becomes substantially irrelevant, and the impedance circuit does not affect the impedance of the system.

By the way, when a short circuit or a ground fault occurs in the system and is detected, all of the circuit breakers "~Ω" or the circuit breaker of the fault phase are opened. This interruption @m-s opens one winding 21B of the pair of split primary windings.

MB and DB are separated, and the other divided windings nm and 1M are separated.

Current flows only through the comb. As a result, a magnetic flux flow occurs in the legs U-U, and a voltage is induced in the secondary windings M, M, 35. As a result, the impedance of the impedance circuit is present in the system, the fault current is suppressed, and its phase 9 time constant is adjusted. Adjusting the time constant is effective for quickly suppressing ground faults and @ line currents. That's it, short circuit.

In order to quickly suppress the ground fault current, it is better to suppress it with a resistor (,%), so it is better to use a series capacitor to reduce the current This is because the value is suppressed by the resistance.

In addition, since the line current is shunted and the shunted current is interrupted, the disconnection capacity of the circuit breaker and V-W only needs to be half the capacity of the fault current. It is durable enough for use.

11211-Maki Figures 4 each show other embodiments of the present invention, and Figure 11X2 shows circuit breaker J-Ω connected to secondary winding M-H.
This is the case when connected between both ends of . In this case, the primary winding is not a divided winding, but the primary winding 21. :22°n is wrapped around the legs 11, 12, and 13.

Fig. 3 shows a case in which only the impedance accruals 41B, aB, and 43B are required to be introduced into the Fi system wire, and there are gaps 16, 1 in the legs 11, 12, and Ll of the iron core W.
7.

There are 18. In addition, in the case of the embodiment shown in FIG.
@ Gap 16 in legs l111-13 by omitting u-at.

17. Just create a river.

Figure 4 shows a case in which a circuit breaker is provided on the secondary side in the same way as the embodiment shown in Figure 2, the impedance circuit is one connection (Δ connection may also be used), and two circuit breakers 32 are connected. ．． : I2. Note that, as in the embodiment shown in FIG.
Even when 1 to 33 are provided on the primary side, the secondary winding waste to X can be Y-connected or Δ-connected.

In each of the above-mentioned embodiments, when the purpose is to suppress fault current, the circuit breaker J-8 is closed during normal times and opened when a fault is detected.

Although the above explanation is about suppressing fault current,
Each of the embodiments can be applied to suppressing the excitation inrush current of a transformer. In that case, the configuration is the same, but the circuit breaker is open when the transformer is powered on.
, after a certain period of time has elapsed after the power is turned on, wsm speed control is activated. The iron core lO is not limited to 5 legs, but 4 legs.
It may have legs or three legs. However, the use of a three-legged core is limited to cases where the purpose is to suppress short-circuit current.

This is due to the following reason.

In other words, a three-leg iron core is used when the magnetic flux axis of each leg is φ7°, but in cases such as ground faults, this relationship does not hold (ju+, 6.+ jw % o), and the magnetic flux does not become 1 zero. This is because it is necessary to create a magnetic path through which the For this purpose, a 4-leg iron core with 1 extra leg may be used, but a 5-leg iron core is usually used for ease of manufacture.

As described above, according to the present invention, the primary winding that carries the line current of the power system is wound around the leg of the iron core, and
An impedance circuit is provided that is electrically coupled to the next winding through electromagnetic induction, and this coupling relationship is controlled by the opening and closing operations of the circuit breaker, thereby reducing the generation of impedance used for current suppression and phase and time constant adjustment. , extinction can be easily controlled, and short circuits, ground fault currents, and transformer excitation inrush currents can be accurately suppressed. Therefore, it can contribute to solving the problem of breaking capacity of circuit breakers in power systems with large power transmission capacity.

[Brief explanation of the drawing]

FIG. 1 is a configuration explanatory diagram showing one embodiment of a current suppressing device according to the present invention, and FIGS. 6 to 4 are configuration explanatory diagrams showing other embodiments of the present invention. IO... Iron core, 11-15... Legs, 16-18.
・Gap, 21-23 ・Primary winding, 21k,
IB, ffA, MB, 23A and ~4jlB...
Reactor, 4IC-do...Capacitor O Figure 3 Figure 4

Claims (1)

[Scope of Claims] (i) An iron core having three or more legs, a primary winding wound around a predetermined leg of the iron core and passing the line current of the power system, and this primary winding. Current suppression characterized by comprising: an impedance circuit electrically coupled to a wire through electromagnetic -4 action; and a circuit breaker that controls the coupling relationship between the primary winding and the impedance circuit by opening and closing operations. Device. As the 11th-order body **, one with a cross-wire structure is used in which the line current is equally shunted and the magnetic flux generated by this shunt current IK is canceled out, and the primary winding and impedance 1j are placed on one side of the shunt path.
2. The current suppressing device according to claim 1, further comprising a circuit breaker for controlling the coupling relationship of the current suppressing device.