JPS59141079A - Equivalence tester for dc breaker - Google Patents

Abstract

PURPOSE:To obtain a highly reliable equivalence tester with a high economy for a DC breaker or the like by providing a reactor between the secondary winding side of a transformer and an auxiliary breaker. CONSTITUTION:A reactor 10 is connected between one end of an over-voltage suppressor 9 on the secondary side of a transformer 2 and an auxiliary breaker 5 connected to a sample commutation switch and voltage is shared with the reactor 10 and an equivalent reactor of the transformer 2. Therefore, only the use of a reactor for high voltage testing suffices eliminating exchange or the like of an auxiliary different in the dielectric strength thereby providing a highly reliable equivalence tester with a high economy for a high voltage/large DC breaker or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an equivalent testing device for DC circuit breakers, and particularly to an equivalent testing device suitable for testing high voltage, large current DC circuit breakers.

[Prior art]

A conventional example is shown in FIG. A generator 1 operated at a low speed of about 10'Hz is used as a power source, and a protective breaker 3 and a closing switch 4 provided on the primary side of the transformer 2 are closed to turn the transformer 2 on.
Auxiliary breaker 5 and test commutation switch 6 installed on the secondary side of
A low-frequency equivalent direct current is applied to the

When cut off, L is set by a current zero point generator connected in parallel with the commutating switch 6 under test, an accelerator L1 discharge gap 7, and a capacitor C charged by a power supply (not shown).
The oscillating current of -C is superimposed on the equivalent direct current flowing through the commutation switch 6 under test, thereby generating a current zero in the cutoff current, and the commutation switch 6 under test is cut off. This cutoff current is commutated to capacitor C. At this time, transformer 2
Since the energy provided on the primary side of the transformer 2 or accumulated in the equivalent inductance of the accelerator 8 and the transformer 2 itself is absorbed by the capacitor C, the interpole voltage of the commutating switch 6 under test increases. Overvoltage suppression device 9 installed on the secondary side of the transformer
(for example, a nonlinear resistor made of a zinc oxide resistor), the overvoltage suppressor 9 becomes conductive, the voltage across the auxiliary breaker 5 is balanced, the auxiliary breaker 5 is cut off, and the power source 1 side The commutation switch 6 under test is disconnected.

Therefore, a step voltage is applied between the electrodes of the commutation switch 6 under test.

That is, according to this method, since a DC voltage can be applied between the poles after the desired current is cut off by the test commutation switch 6, a test equivalent to the actual system can be performed.

In this case, the overvoltage suppression device 9 includes the test commutation switch 60
The same effect can be obtained even if it is provided at both ends.

However, as described above, since the auxiliary breaker 5 is disconnected by balancing the voltages across the auxiliary breaker 5, the voltage on the power supply side must withstand up to the voltage to be applied to the commutation switch 6 under test. Therefore, to verify the breaking capability of the test commutator switch 6 with a rated voltage of 500 kV, the overvoltage multiple is set to 1.6.
It is necessary to apply a DC voltage of 00 kVp between the poles, and insulation of 800 kVp on the power supply side is also required. However, there is no test equipment capable of testing these large currents and high voltages, and manufacturing a new one requires significant costs and is uneconomical. Also, there is no DC system in Japan that can be tested in the field.
It was necessary to develop an economical equivalent test device.

[Purpose of the invention]

An object of the present invention is to provide an economical and reliable equivalent testing device for large-capacity DC circuit breakers.

[Summary of the invention]

The non-invention is that in addition to the equivalent reactor of the transformer used on the power supply side, a new high-voltage test glue handle is provided on the power supply side, and the voltage is shared between this reactor and the equivalent reactor of the transformer, thereby making it possible to perform p1 high voltage testing. This made it possible to verify the breaker performance of DC breaker. This method only requires adding a reactor to the existing test equipment, and is extremely economical.

In addition, the reliability is also high because the same characteristics can be confirmed through computational analysis.

[Embodiments of the invention]

An embodiment of the present invention will be explained below with reference to FIG. Components having the same functions as those of the conventional example are indicated by the same reference numerals. FIG. 2 shows the prior art, in which an overvoltage suppression device 9 is provided on the secondary side of the transformer 2 shown in FIG. At both ends of the series circuit of the breaker 5 and the commutation switch under test 6, and at both ends of the commutation switch under test 6, overvoltage suppression devices (for example, nonlinear resistors made of zinc oxide resistors) 11 and 12 with the same limiting voltage are installed. It is connected.

FIG. 3 shows an example of the waveforms of the current l flowing through the test commutating switch 6 and the voltage V between electrodes. An example of the operation of this embodiment will be explained based on FIGS. 2 and 3. Before the test, the auxiliary breaker 5 and the commutation switch 6 under test are turned on, and the capacitor C'tl of the current zero point generator is charged to a desired voltage by a power source (not shown). Generator 1'! When operating at a low speed of about 1=10 Hz and turning on the protective breaker 3 and the closing switch 4, a low-frequency DC current flows through the commutation switch 6 under test. At time t1, the auxiliary breaker 5 and the test commutation switch 6 are opened.

At time t2 when the test commutation switch 6 can be cut off, the discharge gap 7 is discharged by a starter (not shown), and the LC oscillating current is superimposed on the DC current flowing through the test commutation switch 6. In this case, the effect is the same even if a closing switch is used instead of the discharge gap. This oscillating current forcibly generates a current zero point, and at time t3, the test commutation switch 6 conducts the current. It is commutated to C and cut off. After the cutoff, the voltage shown in FIG. 3 is applied to the commutation switch 6 under test.

Since the voltage of the capacitor C becomes negative on the cut-off side 13 in the figure, the voltage between the electrodes initially becomes negative. Thereafter, the energy accumulated in the power supply side reactor is commutated to the capacitor C, so that the voltage between the poles increases with positive polarity as shown in the figure. The voltage is the voltage required for performance verification of the commutation switch under test (for a DC breaker with a rated voltage of 500 kV, it is 800 kVp, which is 1.6 times
), the overvoltage suppressor 11.12 becomes conductive, and the current on the power supply side is shunted to the overvoltage suppressor 11.12, and the current is cut off. The auxiliary circuit breaker 5 has both overcurrent suppression devices 11.
12 becomes conductive and is cut off at time t4 when the voltages across the auxiliary breaker 5 are balanced. Therefore, a DC voltage V is applied between the poles of the commutation switch 6 under test, with the voltage limited by the overvoltage suppressor 12 remaining on the capacitor.

In this case, the present invention adds a high voltage to one end of the accelerator 10 (for a rated voltage breaker of 500 kV, 8
00 kVp) is applied, but a voltage divided by the equivalent reactor of the transformer 2 and the value of the reactor 10 is applied to the secondary side of the transformer. For example, if you choose this ratio to be 1/8,
The secondary side of transformer 2 is 1/:8! voltage (100kVp-K for SOOKV. In other words, it is possible to perform high-voltage cutoff verification tests with a low-voltage power supply. Generally, the power supply capacity is limited, so there are cases where it is not possible to increase the reactor lOO value by a certain amount. In this case, the limiting voltage of the overvoltage suppressor 9 may be set to, for example, 1/1/1 of the limiting voltage of the overvoltage suppressor [11].
When set to 8, the voltage on the secondary side of the transformer can be limited to 1/8, so a similar effect can be expected. That is, even if the value of the reactor is not necessarily selected as the voltage sharing ratio, there is an effect that the power supply side can be protected.

FIG. 4 shows another embodiment, in which the power supply side and the oscillating current generation source side are omitted. If the power source side can be sufficiently protected only by the share of the power source side equivalent reactor/acdle 10, the overvoltage suppressors 9 and 11 on the power source side can be omitted.

Figure 5 shows a modification of Figure 2, with reactor 1
The overvoltage suppressor 13 is connected between the terminals of the reactor and the overvoltage suppressor 13 is omitted, and the overvoltage suppressor 11t shown in Fig. 2 can be divided and arranged according to the voltage sharing ratio. O In the other embodiment shown in section 6, the overvoltage suppressing device 12 shown in FIG. 2 is omitted, which has an economical effect. This method has the disadvantage that the residual voltage of the capacitor varies considerably depending on the current to be cut off, but this can be overcome by increasing the limit voltage of the overvoltage suppressor 11.

Although the explanation has been omitted in the above embodiments, it is similar to the one provided at both ends of the test commutator switch 60 for the purpose of protecting between the terminals of the auxiliary breaker 5 shown in the embodiments shown in Fig. 2 and below. It is also possible to provide an overvoltage suppression device between the terminals of the auxiliary circuit breaker 5.

FIG. 7 shows another embodiment using a capacitor 14 as the power source. The secondary side circuit of the transformer 2 is omitted because the embodiments shown in FIG. 2 and subsequent figures can be applied. On the primary side of the transformer 2, there is a capacitor 1 charged by a charging device (not shown).
4, closing switch 15, and current adjustment reactor 16
When testing, connect all series circuits of
The same effect as using a generator as a power source can be obtained by closing the generator and passing a low-frequency current through it.

〔Effect of the invention〕

According to the present invention, by adding only a reactor to conventional test equipment, an equivalent test of a high voltage, large current DC breaker can be accomplished in an economical manner.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a conventional equivalence test device, and Fig. 2 is an example of an equivalence test device to which the present invention is applied. 3 is a voltage and current waveform diagram showing the operation example of FIG. 2, FIGS. 4 to 6 are circuit diagrams showing examples of other equivalent test equipment, and FIG. FIG. 7 is a circuit diagram showing another embodiment. 5... Auxiliary breaker, 6... Test commutation switch, 9
...Nonlinear resistance, 10...Reactor, 11-13
...Non Figure 1 Figure 4 Figure 6 Calculation 7 Kasumi procedural amendment (method) % formula % 4 Akira's name DC breaker equivalence test equipment Shin 1 Kawarari Residence (〒]OO) Tokyo 5-1 Marunouchi-chome, Chiyoda-ku, Miyako Prefecture Documents to certify. Heavy industry content See attached sheet.

Claims (1)

[Scope of Claims] 1. A DC breaker equivalence test device comprising a power source combined with a transformer and an auxiliary breaker and a test DC breaker connected in series on the secondary side of the transformer, wherein said transformer An equivalent test device for a DC breaker, characterized in that a reactor is provided between the breaker and the auxiliary breaker. 2. In the item described in claim 1 above, the secondary side of the transformer, the reactor, the auxiliary breaker, between the terminals of the DC breaker under test, and between the connection point of the reactor and the auxiliary breaker and the transformer. An equivalent testing device for a DC breaker, characterized in that an overvoltage suppressor is provided at one end of the secondary side of the device. 3. An equivalent testing device for a DC breaker according to claim 2, characterized in that the overvoltage suppression device is a nonlinear resistor.