JP3035897B2 - Arc extension method in three-phase synthesis test of high voltage circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arc extension method in a three-phase synthesis test of a high-voltage circuit breaker, and more particularly to an arc extension method in a three-phase synthesis test of a three-phase circuit breaker.

[0002]

2. Description of the Related Art With the increase in the voltage and capacity of a three-phase circuit breaker, the short-circuit breaking performance of the three-phase circuit breaker has been verified.
Since the three-phase cutoff is housed in the same tank, it is necessary to verify the performance including the effects of the inter-phase recovery voltage and the electromagnetic force in addition to the inter-electrode recovery voltage.

[0003] However, the direct test has a limit in the output of the short-circuit test site in terms of the supply of three-phase power, so that at present it is absolutely necessary to apply the three-phase synthesis test.
A variety of three-phase synthetic test methods have been proposed, but none have yet been adopted in formal standards. One of them is a test circuit for performing the three-phase synthesis test method shown in FIG.
This test circuit is composed of the first phase cutoff phase (A phase) of the circuit breaker 1 under test.
In addition, a Weil circuit (voltage source circuit) for applying the Weyl test method is used, and a step-up transformer 5 for applying the ski method is used for each of the second and third phase cutoff phases (B and C phases). It is used by being connected in parallel to the C-phase auxiliary circuit breakers 2, 2 '.

Furthermore, an arc extension circuit 7 is arranged on the power supply side of the auxiliary circuit breakers 2, 2 ', 2 "in order to adjust the arc time of the circuit breaker 1 under test.

[0005]

In the above-described conventional three-phase composite test method, the arc extension is required together with the three-phase short-circuit current, and the auxiliary circuit breaker 2 and the test circuit breaker 1 are used for each phase. It is necessary to extend the arc with respect to two circuit breakers connected in series. Therefore, the more the development of the one with good breaking performance, the more difficult it becomes to extend the arc in inverse proportion to it, and the test efficiency is greatly reduced. The present invention has been made in view of the above point, and provides an efficient arc extension method with a small capacity of arc extension energy.

[0006]

An arc extension circuit is connected to an intermediate point between the auxiliary circuit breaker and the test circuit breaker through an arc extension circuit separation switch, and the auxiliary circuit breaker and the arc extension circuit separation switch are opened. The timing at the extreme point is adjusted so that the arc extension with different timing for each interruption phase can be performed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The arc extension method of the present invention will be described with reference to a test circuit shown in FIG.

In FIG. 2, reference numeral 1 denotes a test circuit breaker in which one of the breaking units is connected to a ground connected. 2,2 '
Is an auxiliary circuit breaker, which is connected between the short-circuit generator 3 and the circuit breaker 1 to be tested via a charging device 9. Reference numeral 4 denotes a Weil circuit (voltage source circuit) for supplying a current to the test phase (A phase) which becomes the first phase cutoff phase of the test circuit breaker 1, and 5 denotes the second and third phases of the test circuit breaker 1. Step-up transformers for supplying a voltage to the test phases (B and C phases) to be cut-off phases, which are respectively connected in parallel to the auxiliary circuit breakers 2 and 2 via short-circuit current suppressing resistors 8. Reference numerals 6, 6 'denote arc extension circuit separation switches connected between the test circuit breaker 1 and the auxiliary circuit breakers 2, 2' for separating the arc extension circuit 7.

Next, a series of operations (sequence) of each device
The arc extension method of the present invention based on the order will be described.
(See FIG. 3) (1) The auxiliary circuit breakers 2, 2 ', the test circuit breaker 1, and the arc extension circuit separation switches 6, 6' are turned on in advance.

(2) When the input device 9 is turned on, a three-phase short-circuit current is supplied from the short-circuit generator 3 and the test circuit breaker 1 is immediately turned on.
, And a control is performed so that the first phase cutoff phase (A phase) has an appropriate arc time. (3) Using a sequence timer (3) The arc is extended when the cutoff current of the first cutoff phase (A phase) passes through the first current zero point (point a). At this time, the first auxiliary circuit breaker 2 opens at the point B after passing the current zero point (point a). By doing so, the “arc extension” from the arc extension circuit 7 only needs to be performed in the first interruption phase (A phase).

(4) Next, the second auxiliary circuit breaker 2 '
Since the auxiliary circuit breaker 2 is opened by the opening command at the point C after a lapse of 5 to 6 ms from the time when the auxiliary circuit breaker 2 opens, the arc extension of the second and third phase breaking phases (B and C phases) This is performed at points b and c. By doing so, the “arc extension” from the arc extension circuit 7 is controlled by the second and third phase cutoff phases (B,
In the case of the C phase as well, the arc extension of each phase is sufficient as in the first phase interruption phase (A phase).

(5) First arc extension circuit separation switch 6
Opens at the same point (point B) with the first auxiliary circuit breaker 2, and the second arc extension circuit separation switch 6 'opens at the same point (point C) with the second auxiliary circuit breaker 2'. .

The two arc extension circuit separation switches 6, 6 'need to have at least the same level of pole insulation and ground insulation as the circuit breaker 1 under test. However, large current interruption performance is not required.

(6) The second and third cutoff phases (B and C phases)
Since the current always passes through the current zero point at least once before the completion of the interruption of the first phase interruption phase (A phase), it is natural that the arc is extended at this point (points b and c).

(7) If the “arc extension” is successful in all three phases, the specified transient recovery voltage is applied to the first phase cutoff phase (phase A) from the Weyl circuit (voltage source circuit) 4 and A normal second and third phase recovery voltage is applied to the three-phase cutoff phase (B and C phases) via the step-up transformer 5.

(8) After the completion of the three-phase shutoff, a series of sequences are completed by shutting off a protection breaker (not shown) on the power supply side after a lapse of 0.1 second or more.

[0017]

As described above, according to the present invention, the arc extension of the test circuit breaker injects excessive energy by adjusting the opening times of the two auxiliary circuit breakers at appropriate timings. Since the arc extension device can be easily carried out without using a small capacity, the arc extension device has a small capacity and the equipment cost is low.

[Brief description of the drawings]

FIG. 1 is a test circuit for performing a conventional three-phase synthesis test method.

FIG. 2 shows a test circuit for performing the three-phase synthesis test method of the present invention.

FIG. 3 shows the current of each blocking phase for explaining the three-phase synthesis test method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Test circuit breaker 2 ... Auxiliary circuit breaker 3 ... Short circuit generator 4 ... Weil circuit 5 ... Boost transformer 6 ... Arc extension circuit separation switch 7 ... Arc extension circuit 8 ... Short circuit current suppression resistance 9 ... Supply device

Claims (3)

(57) [Claims] 1. A method for synthesizing a three-phase circuit breaker for supplying a three-phase short-circuit current from a short-circuit generator to a test circuit breaker via a closing device and an auxiliary circuit breaker, and verifying the short-circuit breaking performance. The arc extending method according to the above, wherein after the break opening time of the circuit breaker under test elapses, the breaking current of the first phase breaking phase is passed from the arc extending circuit through the first separation switch after passing the zero point of the breaking current. A current is supplied to extend the arc of the first phase interruption phase, and then the first auxiliary circuit breaker and the first separation switch are opened to open the voltage connected between the test circuit breaker and the first auxiliary circuit breaker. A recovery voltage is applied from the power supply circuit, and after a lapse of the disconnection opening time of the circuit breaker under test, a current is supplied from the arc extension circuit through the second separation switch to the second and third circuits.
The arc at the time of phase interruption is extended, and then the second auxiliary circuit breaker and the second separation switch are opened to bypass the second auxiliary circuit breaker, respectively, via the step-up transformer connected to the test circuit breaker. The method of extending a three-phase circuit breaker according to claim 1, further comprising applying a recovery voltage. 2. The circuit according to claim 1, wherein the first auxiliary circuit breaker and the second auxiliary circuit breaker are operated as separate auxiliary circuit breakers for each phase, and are separately operated for the first phase circuit breaker and the second and third phase circuit breakers. An arc extension method in a synthesis test of the three-phase package type circuit breaker according to claim 1. 3. The opening of the first auxiliary circuit breaker is performed during the last half-wave energizing time of the breaking current of the first phase breaking phase, and the opening of the second auxiliary circuit breaker is performed by opening the first auxiliary circuit breaker. 3. The method of claim 1, wherein the time is 5 to 6 milliseconds.