JPS6021799Y2 - Synthetic test equipment for three-phase bulk breaker - Google Patents

Description

[Detailed description of the invention] This invention relates to the synthesis test of circuit breakers, especially three-phase bulk operation type circuit breakers or three-phase bulk tank type circuit breakers in which three-phase arc extinguishing chambers are housed in the same tank. (hereinafter referred to as a three-phase block circuit breaker), the three-phase circuit breaker has no physical interaction of the three phases for the closing and disconnecting duties, and its performance is determined independently. If the performance as a three-phase breaker is confirmed by a single-phase test, the standard (for example, JEC-181) recognizes that it can be performed by a single-phase test.

This single-phase test also includes a direct test using only a short-circuit generator as the test power source, and a synthetic test as an equivalent test method.

In addition, due to the flow of three-phase arc currents as in a three-phase bulk breaker, it is expected that there will be effects such as a reduction in operating force, a decrease in interrupting performance due to mutual interference between the arcs, and a decrease in withstand voltage between phases and ground. In the case of test circuit breakers, it is necessary to verify their performance through three-phase tests.

An equivalent test method for this is to supply a three-phase short-circuit current from a short-circuit generator, and then apply the restart voltage and recovery voltage from the voltage source circuit only to the pole of the test breaker, which is the first-phase cutoff among the three phases. Proposals have also been made for synthetic test equipment that applies this voltage.

According to this device, the auxiliary breaker and the voltage source circuit are connected to the pole that serves as the first phase cutoff of the test breaker,
Verification of the interrupting performance is performed mainly for the phase-to-electrode, where the re-electromotive voltage applied between the in-phase electrodes is the most severe.

However, the arc energy generated in the arc extinguishing chamber during the cutoff process is larger in the new wind of the first phase, and the re-electromotive voltage generated between the two phases that becomes the second phase cutoff is It is impossible to conduct tests for two-phase newly built buildings, which are more severe than those for phase-blocking.

In addition, the circuit breaker has the ability to cut off short-circuit current (-0-duty), and is capable of forcibly turning on the system from the cut-off state regardless of whether or not the grid fault continues, and if the fault continues, it immediately It is required to have the ability to shut off (-CO-responsibility).

It is also impossible to conduct tests with this device in response to this request.

The purpose of this invention is to connect an auxiliary breaker to one of the poles that serve as the second phase breaker of the test breaker in a three-phase composite test of a three-phase bulk breaker, and to open and close the voltage source circuit freely. The object of the present invention is to provide a 10-duty and -CO-duty combination test device for second phase cutoff by connecting to this pole through a device.

Hereinafter, specific embodiments of the present invention will be explained in detail with reference to the test circuit diagrams shown in FIGS. 1 and 2 and the phenomenon diagram shown in FIG. 4.

FIG. 1 shows a conventional synthetic test device mainly intended for verifying the interpolation performance of the first phase of a three-phase collective circuit breaker.

In FIG. 1, a three-phase short-circuit generator 1. Closing switch 2) The current limiting reactor 3 and the test circuit breaker 5 are connected in series, and a single-phase An auxiliary breaker 4 is connected to form a three-phase current source circuit.

In addition, the main capacitor 11. is charged in advance with a DC charging device (not shown). A starting gap 10, a voltage source reactor 9, and a series branch circuit of a restart voltage adjusting resistor 7 and a restart voltage adjusting capacitor 8 are connected in parallel with these to form a voltage source circuit.

A three-phase composite test circuit is constructed by connecting the connection point between the auxiliary breaker 4 and the test breaker 5 of these two circuits, and the connection point between the voltage source circuit reactor 9 and the restart voltage adjustment resistor 7.

In this synthetic test device, since the auxiliary breaker 4 and the power supply circuit are connected to the pole of the test breaker 5 that serves as the first phase cutoff, the operating force is reduced due to the arc and arc energy generated during the breaker operation process. It is not possible to perform performance verification tests when the second phase is shut off, where the re-electromotive voltage region between phases is even more severe.

In addition, in the -CO- duty three-phase composite test, the voltage of the three-phase short-circuit generator 1 is increased with the closing switch 2 and the auxiliary breaker 4 of the current source circuit closed, and the supply voltage of the current source is specified. adjusted to the value.

(At this time, if the capacity of the three-phase short circuit generator 1 is insufficient,
The supply voltage at the time of turning on becomes a reduced voltage.

) Therefore, the sum of the DC charging voltage of the main capacitor 11 and the AC supply voltage of the current source is applied between the electrodes of this starting gap 10, and there is no starting command from a starting control device (not shown). Even if the starting gap 10 self-destructs, the voltage source will start.

In order to avoid this malfunction, if the gap of the starting gap 10 is set to sufficiently withstand the above-mentioned sum voltage, there may be a delay in starting or no operation when a voltage source starting command is issued. There was a drawback that it was impossible.

FIG. 2 shows a three-phase synthesis test apparatus according to the present invention.

The difference from the conventional synthetic test equipment shown in FIG. It is connected to the connection point between the auxiliary breaker 4 and the test breaker 5.

The operation of the test apparatus according to the present invention will be explained in detail with reference to the phenomenon diagram of the -CO-duty match test shown in FIG.

The closing switch 2 and the auxiliary breaker 4 are closed in advance, and the voltage source connection switch 6 and the test breaker 5 are open.

The supply voltage from the short-circuit generator 1 at the time of turning on is applied to each phase terminal on the power supply side of the test breaker 5 and the current source side terminal of the voltage source connection switch 6.

Next, when a closing command is given to the test breaker 5 and it performs a closing operation, a pre-arc is generated between the contacts of each phase at time t1, or the contacts mechanically contact each other, resulting in a three-phase short circuit state. Therefore, the specified three-phase short circuit current flows.

At a subsequent time, the voltage source connection switch 6 is turned on to connect the voltage source circuit and the current source circuit.

At this time, since the test breaker 5 is short-circuited between the electrodes of the starting gap 10 (main capacitor 11
Only the DC voltage that was previously charged will be applied, so no false starts will occur.

Next, a cutoff command is given to the test breaker 5 so that the pole to which the auxiliary breaker 4 and the voltage source are connected becomes second phase cutoff, and a cutoff command is also given to the auxiliary breaker 4.

At this time, the test circuit breaker 5 is opened at time t3, and the
The current of the phase that should be cut off is cut off at its current zero point.

Therefore, the remaining two phases that have not reached the current zero point form a single-phase circuit, and the arc current continues.

At time t, the auxiliary circuit breaker 4 opens, just before the zero point time finger of the short circuit current 1b (generally 400 μs to 500 μs before)
At the time , a starting gap 10 controlled by a starting device (not shown) is triggered, and a voltage source current jh flows through the voltage source reactor 9.

Here, the voltage source current ik is superimposed on the current i of the phase under test of the breaker 5 under test.

The current supplied from the short-circuit generator 1 is cut off by the auxiliary breaker 4 at time t6, and the voltage source current ik, which continues to flow only through the test phase of the test breaker 5, is cut off at time t7.

Immediately thereafter, a restart voltage ep determined by the voltage source circuit constants is applied between the poles of the test breaker 5, and at the same time,
The sum of the re-electromotive voltage from the current source applied between the poles of that phase and the re-electromotive voltage e2 applied to the phase under test shall be applied between the phases with the other phase that has caused the second phase cutoff. This becomes a severe disconnection condition, considering that the arc energy injected into the arc extinguishing chamber is larger.

As explained above, the three-phase collective breaker synthesis test device according to the present invention includes a current source circuit that supplies a specified three-phase short circuit current to the three-phase trial breaker, and a second circuit breaker of the three-phase trial breaker. An auxiliary breaker installed in series only on the phase that will cut off the phase of The voltage source circuit includes a voltage source circuit, and a switching device that is provided between the three-phase service breaker and the voltage source circuit and electrically connects them.

Therefore, in addition to the three-phase 10-duty synthetic leather test, which targets the second phase breaker, which is particularly severe in terms of arc energy and mutual insulation, the three-phase collective breaker
It becomes possible to carry out the duty matching test without self-destruction of the voltage source starting gap due to the current source voltage, and it becomes possible to verify the interrupting performance equivalently to a three-phase direct test.

In addition, because the test equipment capacity of the current source is small, the arc current is interrupted at the current zero point where it should originally continue, and the arc does not extend to the specific arc time of the test circuit breaker 5, making a synthetic test impossible. In such cases, as shown in Figure 4, a three-phase collective breaker test can be performed by installing a three-phase arc extension device that forces the re-ignition and continues the three-phase arc current. becomes.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing a conventional three-phase block breaker synthesis test device, Fig. 2 is a circuit diagram showing an embodiment of a three-phase block breaker synthesis test device according to the present invention, and Fig. 3 is a circuit diagram of the same. The voltage-current characteristic diagram and FIG. 4 are circuit diagrams showing another embodiment of the present invention. 1... Short circuit generator, 2... Closing switch, 3... Current limiting reactor, 4... Auxiliary breaker, 5...・If it is a sample, disconnect the device, 6...
・Switch for voltage source connection, 7... Resistor for adjusting the restart voltage, Capacitor for adjusting the restart voltage, 9.
...Voltage source reactor, 10... Starting gap, 11... Voltage source main capacitor.

Claims (1)

[Scope of utility model registration request] a current source circuit that supplies a specified three-phase short circuit current to the three-phase trial breaker; an auxiliary breaker provided in series only to the second phase of the three-phase trial breaker; A voltage source circuit including a main capacitor that is connected to the second phase of the complementary trial breaker and applies a specified voltage after current interruption, and between the three-phase trial breaker and the voltage source circuit. 1. A synthetic testing device for a three-phase collective circuit breaker, comprising a switchgear that can be opened and closed to electrically connect these circuit breakers.