JP2646881B2 - Insulation characteristics test equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an insulation characteristic test apparatus for verifying long-term electrical reliability of a sample such as an electrical device and an insulating material used for the electrical device. It is.

[0002]

2. Description of the Related Art For example, in conventional high-voltage equipment such as transformers and transformers, it is necessary to guarantee the electrical reliability of the equipment for a long period of time. For this reason, using an insulation property tester, apply a voltage that takes into account the safety factor for a long time to a model that simulates the high-voltage part of an actual product or equipment or a sample such as an insulating material that is used in equipment However, by measuring the time until dielectric breakdown, it is confirmed that there is no problem with the product life, and the reliability is improved by improving the weak points.

In order to shorten the test time, the frequency of the power application device is set to a frequency higher than the commercial frequency, the time is accelerated, and the time required for dielectric breakdown is measured. Measurement of partial discharge characteristics and the like for detecting minute discharge generated from a sample is also performed.

[0004]

Since the conventional insulation characteristics test apparatus is constructed as described above, when measuring the partial discharge characteristics while applying a high frequency in order to shorten the test time, a high frequency is required. The lower the resolution of the discharge detection of the measuring instrument becomes, the lower the accuracy of the partial discharge charge amount , the generation place, the generation phase, and the like becomes. For this reason, when measuring the partial discharge characteristics, the application of the electric power to the sample is interrupted, and the commercial frequency is applied using another power supply device. In this case, there are problems such as the intervals of the measurement time of the partial discharge characteristics being varied, and the behavior before the destruction of the sample is not known, or the behavior of the partial discharge generation being changed by stopping the application of electric power. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has an insulation characteristic test capable of accurately measuring a partial discharge characteristic of a sample without interrupting power application to the sample. The aim is to obtain a device.

[0006]

An insulation characteristic test apparatus according to the present invention switches the frequency of a test power supply for generating a high voltage applied to a sample between a test high frequency and a commercial frequency via a switching device. Oscillator that oscillates and the amount of partial discharge generated from the sample being charged at a high frequency for testing is compared with a preset set value, and if the amount of partial discharge is smaller than the set value , the oscillator is controlled and with switching on the high-frequency for re-testing was continued a predetermined time is switched to the commercial frequency from the test frequency number, partial discharge charge quantity is set
If the value is larger than the fixed value, the oscillator is controlled to switch the frequency from the test high frequency to the commercial frequency and continues until the sample is destroyed, and the part where the frequency oscillated by the oscillator is switched to the commercial frequency And a partial discharge characteristic measuring device for measuring discharge characteristics.

[0007]

According to the present invention, the determination apparatus for the insulation characteristic test apparatus compares the amount of partial discharge charge generated from the sample being charged with a preset set value, and switches the oscillator if the amount of partial discharge charge is smaller than the set value. controlled with switching to the test high frequency again after continuing a certain time is switched to the commercial frequency frequency from the test high frequency, the partial discharge charge amount setting
If it is larger than the predetermined value, the oscillator is controlled to switch the frequency from the test high frequency to the commercial frequency, and the operation is continued until the sample is destroyed.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a block diagram showing a configuration of an insulation characteristic test apparatus according to one embodiment of the present invention. In the figure, reference numeral 1 denotes a test power supply for generating a high voltage, and 2 denotes an oscillator connected to the primary side of the test power supply 1, which can set any two frequencies, an arbitrary frequency and a commercial frequency. The output frequency is switched to any one via the device 3. Reference numeral 4 denotes a sample connected to the secondary side of the test power supply 1 to which a high voltage for testing is applied. Reference numeral 5 denotes a current detector connected to the low voltage side of the sample 4 and detecting a minute current generated in the sample 4.

Reference numeral 6 denotes a partial discharge measuring device for amplifying and shaping the minute current signal detected by the current detector 5 to measure a partial discharge. Reference numeral 7 denotes a recorder connected to the partial discharge measuring device 6 for recording a measured value. , 8 are switching device 3, partial discharge measuring device 6
And a recorder 7, each of which compares a discharge charge amount measured by the partial discharge measuring device 6 with a preset set value, and controls a time interval for switching the frequency of the oscillator 2 according to the comparison result. This is a discriminating device for instructing the recorder 7 whether to record the measurement result of the partial discharge characteristic.

In the insulation characteristics testing apparatus according to one embodiment of the present invention, a high-frequency test voltage is normally applied to the sample 4 by the test power supply 1, and the portion generated from the sample 4. The amount of discharged charge is determined by the current detector 5
And measured by a partial discharge measuring device 6 and monitored by a recorder 7. On the other hand, the discriminating device 8 compares the set value preset to a predetermined value with this partial discharge charge amount . For example, when the partial discharge charge amount is smaller than the set value,
The frequency of the oscillator 2 is switched from the high voltage to the commercial frequency via the switching device 3 to perform partial discharge at the commercial frequency.
Partial discharge characteristics such as the amount of charge , the number of generations, and the generation phase are measured for a certain period of time and recorded in the recorder 7.

Thereafter, the frequency of the oscillator 2 is switched again from the commercial frequency to the high power application frequency via the switching device 3, and the power application at the high frequency is continued, and thereafter the same operation is repeated at regular time intervals. If the amount of the partial discharge charge generated from the sample 4 exceeds the set value, the frequency of the oscillator 2 is switched from the high frequency to the commercial frequency via the switching device 3 and the partial discharge until the sample 4 is destroyed. To clarify the characteristics,
Until the sample 4 destroys the partial discharge characteristics at the commercial frequency,
It is measured continuously or at regular time intervals and recorded in recorder 7.

According to the above embodiment, it is possible to measure the partial discharge characteristics of the sample 4 at regular time intervals without interrupting the application of power to the sample 4, and to clarify the behavior of the sample 4 before breaking. In addition, since the partial discharge characteristics are measured at the commercial frequency, there is an effect that the measurement can be accurately performed using a normal measuring instrument.

[0013]

As described above, according to the present invention, the oscillator which oscillates by switching the frequency of the test power supply for generating the high voltage applied to the sample between the test high frequency and the commercial frequency via the switching device. Then, the partial discharge charge generated from the sample being charged at the high test frequency is compared with a preset set value, and if the partial discharge charge is smaller than the set value , the oscillator is controlled to set the frequency to the test high frequency. After switching from the frequency to the commercial frequency and continuing for a certain period of time, switch to the test high frequency again.If the partial discharge charge is larger than the set value , control the oscillator to switch the frequency from the test high frequency to the commercial frequency and change the sample. And a partial discharge characteristic measuring device that measures partial discharge characteristics while the frequency oscillated by the oscillator is switched to the commercial frequency. , Can be obtained without interrupting the voltage application to the sample, the insulating property testing apparatus which can accurately measure the partial discharge characteristics of the sample.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an insulation characteristic test apparatus according to an embodiment of the present invention.

[Explanation of symbols]

1. Test power supply, 2 oscillators, 3 switching devices, 4 samples, 6 partial discharge measuring devices, 8 discriminating devices.

Claims (1)

(57) [Claims] In an insulation characteristic test apparatus for performing a test by applying a high voltage to a sample, the frequency of a test power supply for generating the high voltage is switched between a high test frequency and a commercial frequency via a switching device. Oscillator which oscillates, compares the amount of partial discharge charge generated from the sample being charged with the test high frequency with a preset set value, and if the amount of partial discharge charge is smaller than the set value , sets the oscillator to Control and switch the frequency from the test high frequency to the commercial frequency, continue for a certain period of time and then switch back to the test high frequency, and if the partial discharge charge amount is larger than the set value , control the oscillator. A discriminator that switches the frequency from the test high frequency to the commercial frequency and continues until the sample is destroyed, and that the frequency oscillated by the oscillator is An insulation characteristic test device, comprising: a partial discharge characteristic measurement device for measuring a partial discharge characteristic during switching to a commercial frequency.