JPS59116067A - Testing method of three phase common tank type breaker - Google Patents

Abstract

PURPOSE:To perform the test approximate to a three-phase direct short circuiting test with one time test by connecting the breaking points of respective phases in series, grounding the prescribed breaking point, and connecting a voltage source of 1.5 times the rated phase voltage and a voltage source of a rated phase voltage between the prescribed phases. CONSTITUTION:The breaking points 4R and 4S of the phase 1 and phase 2 among breaking points 4R, 4S, 4T of the respective phases which are connected in series are kept grounded and connected, and currents are supplied from the respective phases 1R, 1S, 1T of a three-phase current source 1 to the respective points 4R, 4S, 4T. On the other hand, a voltage source 5a of 1.5 times the rated supply voltage is connected, via an auxiliary breaker 3, between the 1R and the point 4R and a voltage source 5B of the rated voltage is connected between the point 4S and the ground. The test approximate to a three-phase direct short circuiting test is accomplished with one test according to the above-mentioned constitution without the increase in the voltage at the breaking point to ground after the breaking or without the decrease in the interphase recovery voltage than the rated voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for synthetic short circuit testing of three-phase common tank type circuit breakers.

A circuit breaker in which the three-phase breaking points are housed in a common tank can cause high-temperature gas containing ions to be released into the common tank due to the high heat of the arc generated between the breaking points when a short-circuit current is cut off due to an accident, etc. There is a potential danger that the insulation between each phase and the grounded common tank will deteriorate as a result. It goes without saying that it is desirable to verify the breaking performance of such circuit breakers using the same three-phase direct short-circuit test method as in the actual system, but it is important to match the short-circuit test equipment capacity with the system capacity. It is almost economically impossible as the system capacity has become so low as in recent years, and for this reason, current sources that can supply large currents with relatively low voltages and those that can supply high voltages with small currents are generally available. It is known that a synthetic short circuit test method in combination with a voltage source is employed.

Since the synthetic short circuit test method for three-phase common tank type circuit breakers has the above-mentioned problems, it is required to satisfy the following conditions.

First of all. ! : to generate an arc for a predetermined period at the three-phase breaker point; It is possible to apply a predetermined voltage to each breaker point of the third phase, between the breaker points, and between the phases and the common tank to ground, and thirdly, it is possible to forcibly extend the arc to obtain a predetermined arc period. The fourth reason is, of course, that the test time can be shortened.

As a conventional synthetic short circuit test method of this type, for example,
The circuit shown in Fig. 1 and Fig. 2 as different examples is known. First, as the circuit shown in Fig. 1, a Y-connected three-phase current source 1 capable of supplying a predetermined short-circuit current is connected to each phase. The current adjusting glue handle 2 is connected, and the current source 1 is connected to the first
The first phase IR of the current source 1, which is a terminal of the reactor 2, is connected to the other second phase IR, the second phase IS, and the third phase IT through the auxiliary breaker 3. The third phase Is, IT is the three-phase breaker point 4R of the direct test breaker 4.

48.4T respectively. A voltage source 5 having a generated voltage of 1.5 times the rated phase voltage is connected to the first phase of the cutoff between the test breaker 3 and the first phase cutoff point 4R,
The anti-mold source sides of each phase breaking point 4R, 48, and 4T are short-circuited and grounded, and an arc extension device 6 at each phase end of the reactor 2 for forcibly extends the arc period.
is connected.

Next, the circuit shown in FIG. 2 will be explained. This circuit is different from the circuit example shown in FIG. Moreover, each phase breaker point 4R, 4S of the test breaker 4
, 4T are connected in series, and the voltage source 5 is connected to the second .
Third breaking point 4S.

Connect between 4T and 1st. This means that the second phase breaking points 4R and 48 are grounded.

For the two circuit configurations above, in the case of Figure 1, 3
That is, the arc extension device 6 of each phase extends the arc of each phase for a predetermined arc period, and the voltage source 5 applies only to the breaking point 4R of the first cutting phase. 6 is required for each phase, which increases costs, and voltage #5 is only applied to one cutoff point 4R of the first phase, and since a voltage 1.5 times the phase voltage is applied, The phase-to-phase recovery voltage of
There was a drawback that the voltage to the ground after the third phase was cut off at the cutoff point of 48.4T became higher.

On the other hand, in the circuit example shown in Fig. 2, the test breaker 4 disconnects the voltage source 5 and the current source 1, that is, it also serves as an auxiliary breaker, so there is no need for an auxiliary breaker, and the arc extension The fact that there are two devices 6, one for the first phase and the third phase, has the advantage of being economical, but in order to apply a voltage 1.5 times the phase voltage to only one phase, the above-mentioned As in the conventional example shown in FIG. There are drawbacks such as the voltage to ground after the third phase is cut off being higher than a predetermined value, and none of these methods satisfactorily meet the requirements. For this reason, in the past, two additional tests were added to these test methods.
Previously, arcs were generated in the phases and a predetermined voltage was applied between the phases where the interphase voltage was insufficient, which also had the disadvantage of making testing cumbersome and requiring a lot of time, and improvements have been awaited. Ta.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks and provide a method for testing a three-phase common tank type circuit breaker that is more similar to the three-phase direct short circuit test and more reasonable in one test.

According to the present invention, the above object is to test the breaking performance of a test piece in which the three-phase breaking point is housed in the same container, and to detect the short circuit current and recovery voltage from separate current sources and voltage sources. In the synthetic short-circuit test method provided, a test breaker in which the breaking points of each phase are connected in series and the first and second phases are grounded, and a test breaker connected to each phase breaking point of the test breaker, a three-phase current source, and a first retrovoltage source with a voltage 1.5 times the rated phase voltage connected between the current source and the first phase of the test breaker via an auxiliary breaker; This is achieved by providing a second voltage source of rated phase voltage connected between the second and third phases of the test breaker.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 3, parts corresponding to the different conventional examples shown in FIGS. 1 and 2 are designated by the same reference numerals to avoid overlapping explanations, and the different parts will be described with K. The difference is that two voltage sources are used, a first voltage source 5a and a second voltage source 5b, and the second voltage source 5b has a phase voltage 10 times that of the test breaker 4, and Others are number one. The structure is a compromise between the two conventional examples shown in FIG.

To explain in detail, the first phase IR of current source 1 and the test switch/disconnector 4
A first voltage source 5a is connected to the first phase disconnection point 4R so that it can be separated by an auxiliary breaker 3.
The second. The second phase of the test circuit breaker 4 connected between the third phase xsptT. 3rd phase 1shi: Yadan, point 4S.

A second voltage source 5b is connected to the series connection side of the 4T.

The series connection point between the breaker points 4R and 48 is grounded, and the arc extension device 6 is connected to the first phase IR and the second phase Is.

In the above configuration, the breaking point of one phase of the breaker is 4R, at which time the first voltage source 5a applies voltage by the current gravimetric method, and the second voltage source 5b The Skeets method of applying voltage is adopted, and as mentioned above, the first voltage source can apply a voltage 1.5 times the phase voltage, and the second voltage source can apply a voltage 10 times the phase voltage.

The results of the above configuration will be explained by comparing them with the three-phase direct short-circuit test method and the conventional synthetic short-circuit test method described above, as shown in FIG. All test conditions are for ungrounded systems.
All numerical values in the figure are shown as multiples of the phase voltage. Fourth
In the conventional test method shown in Fig. 1 and Fig. 2, for example, the phase voltage of the 2nd and 3rd phase breaker or the recovery In contrast to parts where the applied voltage is low (approximately 87%), such as the steady voltage value, and parts where it is extremely high, such as the ground voltage, from 15 times to 1.73 times, in this example, the applied voltage There is no area where the value is lower, and even where it is higher, it is only 1.44 times the maximum, which means that the rationality is greatly improved.

This configuration is a three-phase common tank type 1. There is no new equipment to be manufactured for the interrupter, and it is possible to use test equipment for three-phase separated tank type circuit breakers that have been commonly used in the past. Since the voltage is automatically applied by adopting the above method, there is an advantage that conventional control technology can be used to control the timing of voltage application.

As described above, according to the present invention, a rational three-phase common tank type circuit breaker synthetic short-circuit test similar to the direct short-circuit test method can be performed using only a selected combination of multiple sets of conventional single-phase synthetic short-circuit test equipment. method is obtained.

[Brief explanation of the drawing]

Figs. 1 and 2 are test circuit diagrams of different conventional synthetic short-circuit test methods for three-phase common tank type circuit breakers, and Fig. 3 is a test circuit diagram of a synthetic short-circuit test method for three-phase common tank type circuit breakers according to the present invention. Test circuit diagram of the embodiment, FIG. 4 is an explanatory diagram comparing the embodiment of the present invention with a conventional example. 1... Three-phase current source, 3... Auxiliary breaker, 4...
Test circuit breaker, 5 a + 5 b...1st. Second voltage source, 6... arc extension device. E 1 Figure 2 Figure T 3 Figure f 4 Figure

Claims (1)

[Claims] 1) A synthesis method for verifying the breaking performance of a test breaker whose three-phase breaking points are housed in the same container by supplying short-circuit current and recovery voltage from separate current sources and voltage sources, respectively. A short-circuit test method, in which a test breaker is connected in series with each phase cutoff point and the first and second phases are grounded, and each phase cutoff point of the test breaker is connected to each other. a three-phase current source, a first voltage source having a voltage 1.5 times the rated phase voltage connected between the current source and one phase of the breaker of the test breaker via an auxiliary breaker, and the test breaker. 2nd and 3rd phase of the vessel
A method for testing a three-phase common duplex circuit breaker, comprising: a second voltage source of rated phase voltage connected between the phases. 2. A three-phase common tank type method according to claim 1, characterized in that an arc period extension device is connected to each of the first phase and second phase of the circuit breaker of the three-phase current source circuit. Test method for circuit breaker.