JPH07117565B2 - Insulation test equipment by partial discharge method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is based on the partial discharge method for measuring and evaluating the condition of insulation deterioration of a test piece such as a generator coil installed in a hydroelectric power plant or the like. The present invention relates to an insulation test device.

[Prior Art] In order to accurately grasp the state of insulation deterioration of generator coils conventionally installed in hydroelectric power stations, etc., and to prevent dielectric breakdown, a generator coil insulation test is regularly performed. Has been implemented. The direct current method is generally used as an insulation test method for insulating materials, but in the case of a generator coil, it is necessary to know the exact state of insulation deterioration. It is a general practice to conduct an insulation test by a method such as a partial discharge method or a partial discharge method, and after checking these test results and making a comprehensive consideration, whether the insulation state of the generator coil is good or bad.

As a partial discharge method in the insulation test of the generator coil,
Conventionally, the voltage-charge analysis method has been frequently performed, but this method has a drawback that it is difficult to predict the time of the dielectric breakdown of the coil, which is the sample. The partial discharge method is also common to voltage-charge analysis methods and other analysis methods.As a disadvantage, the partial discharge method is easily affected by noise from the external environment, and adjustment of the device during measurement is difficult. When performing a discharge test, a high level of measurement technology and experience is required, and it is necessary to entrust it to a specialized contractor, and there are problems that the test date and time are restricted and the test cost becomes expensive.

Furthermore, when shifting from the measurement by the partial discharge method to the measurement by, for example, the direct current method or the alternating current method, in the past, completely separate measuring devices or systems were used. The change must be made each time, and there is also a problem that the time and manpower required for the comprehensive insulation test of the generator coil becomes enormous.

[Object of the Invention] An object of the present invention is to solve the above problems, achieve good operability, reduce test time, and save labor in input, and facilitate processing of test data and evaluation of the state of insulation. An object of the present invention is to provide an insulation test apparatus by the partial discharge method, which can perform the judgment of the degree of dielectric breakdown.

[Summary of the Invention] An insulation test apparatus by a partial discharge method according to a first aspect of the invention for achieving the above object is a control circuit for connecting an operation terminal device to control the entire apparatus, and an interface with the control circuit. And a voltage-charge analysis function unit that analyzes the insulation state of the specimen based on the amount of discharge charge with respect to the applied voltage,
Directly coupled to the control circuit and generating phase of partial discharge pulse φ
And the voltage from the AC high-voltage power supply unit, which adjusts and outputs the voltage from the strain level plane analysis function unit that analyzes the insulation state of the sample by the strain level based on the cycle average φ-q distribution obtained from the discharge charge q It is composed of a voltage automatic adjustment unit, the voltage-charge analysis function unit and the skewness plane analysis function unit are connected to the voltage adjustment unit, and the test piece is the voltage automatic adjustment unit, the voltage-charge analysis function unit, the skewness plane. It is characterized by being connected to the analysis function unit.

In addition, the insulation test apparatus by the partial discharge method according to the second aspect of the present invention includes a control circuit that connects an operation terminal device and controls the entire apparatus, and a voltage-charge analysis function that is connected to the control circuit through an interface section. Section and an automatic voltage adjusting section that adjusts and outputs the voltage from the AC high-voltage power supply section, and the automatic voltage adjusting section and the voltage-charge analysis function section connected to the test piece are provided by the automatic voltage adjusting section. During the step-up process, the discharge charge amount of the sample for the first voltage value which is the maximum applied voltage and the second voltage value which is lower than the first voltage value by a constant voltage is measured, and the discharge charge amount is compared with these discharge charge amounts. It is characterized in that the slope of the maximum discharge charge amount of the specimen is calculated by

[Examples of the Invention] The present invention will be described in detail based on examples for carrying out an insulation test on a generator coil in the illustrated hydroelectric power plant.

FIG. 1 is a block circuit configuration diagram showing a basic configuration of an insulation test apparatus by the partial discharge method according to the present invention, in which a control circuit 1 includes an operation terminal device 2, an interface section 3, and a strain plane analysis function section 4. The interface section 3 is also connected to the automatic voltage adjusting section 5 and the voltage-charge analysis measuring section 6 so that the phase direction data communication is possible.

The output terminal of the AC high-voltage power supply section 7 is connected to the input terminal of the automatic voltage adjustment section 5, and the output terminal 5a of the automatic voltage adjustment section 5 is connected.
The conducting wire connected to is connected to the voltage-charge analyzing and measuring instrument section 6 through the blocking coil 8 and one end of the grounded test coil CL, and the other end through the coupling capacitor 9. Has been done.

Further, the output terminal 5b of the voltage automatic adjustment unit 5 is connected to the strain degree plane analysis function unit 4, and the calibrator 10 is connected to both ends of the test coil CL. It is also connected to the plane analysis function unit 4.

Next, the function of each unit configured as described above will be described. First, the control circuit 1 is a unit that controls the entire apparatus, outputs a control signal to each unit, and performs arithmetic processing of measurement data fetched from each unit and Evaluate. Therefore, a computer capable of performing high-speed and complicated data processing is suitable, but a personal computer is most suitable in consideration of downsizing of the entire apparatus.

As the operation terminal device 2 connected to the control circuit 1, for example, a general personal computer input keyboard 2a, monitor display 2b, printer 2c, plotter 2d, and the like are arranged, and a necessary control signal is input from the keyboard 2a. By doing so, the insulation test can be performed, and the measurement data and the like can be output to the monitor display 2b, the printer 2c, and the plotter 2d as necessary, and can be used for preparing a report or the like.

The interface section 3 has both A / D and D / A conversion functions, converts the analog output measurement data into a digital signal and sends it to the control circuit 1, or converts the digital signal from the control circuit 1 into an analog signal. The operation of converting and sending to each unit is performed.

In general, the insulation test of the generator coil and the like is not limited to the partial discharge method, but in many cases, other insulation tests such as the direct current method and the alternating current method are also performed. In such a case, the control circuit 1 If a connection terminal is provided on the interface part 3 or
Since another insulation test device 11 can be connected, the time required to complete the entire test is shortened. Of course, in that case, it is necessary to change the specifications in the control circuit 1, but if a personal computer is used, only a slight change in the program is required, which is efficient.

Next, the portion directly involved in the actual measurement will be described, but this insulation test apparatus has two types of test methods, that is, a strain plane analysis and a voltage-charge analysis. First, the skewness plane analysis function unit 4 is internally provided with its own CPU for data processing, and when measurement is performed, statistical calculation processing is performed, and the maximum discharge charge qmax and the skewness S of the cycle average φ-q distribution are calculated. (Skewness value) is automatically calculated and transferred to the control circuit 1.

Here, the skewness plane analysis will be described. All the data of the partial discharge may be recorded in time series including the voltage phase angle, but it cannot be analyzed as it is. Therefore, some kind of averaging operation including the phase angle is required, and it is conceivable to average the partial discharge pulses generated in the phase window which is a minute phase section obtained by dividing the phase angle into several.
A cycle average φ-q distribution obtained by adding the discharge pulses generated in each phase window and dividing by the number of cycles appears as a pattern, and the partial discharge can be analyzed based on the distortion degree S as a value expressing this.

The partial discharge pulse data measured time-sequentially is stored in a memory by measuring the pulse generation phase φ (the positive zero cross is a phase angle of zero) and the magnitude q of the partial discharge charge in each cycle. After measuring an appropriate number of cycles, a cycle average φ-q distribution is calculated using the obtained paired data of φ and q. The method of calculating the φ-q distribution is to obtain the sum of the partial discharge charges q in the same phase section, then divide the total charges by the number of measurement cycles to obtain the average discharge charges in that phase. The cycle average φ-q distribution can be classified into typical distribution shapes such as a square distribution, a triangular distribution, a normal distribution, and an exponential distribution, and the skewness S is obtained from the deviation of these distribution pattern shapes. For example, when the degree of distortion S is large and positive, it can be determined that the electric discharge is concentrated in the small phase angle portion.

Various settings for calibration and measurement can be automatically performed by inputting the rated voltage E of the test coil to the internal CPU of the skewness plane analysis function unit 4 by inputting a signal from the terminal device 2 for operation. It's easy. The voltage-charge analysis measuring unit 6 is a part for performing a voltage-charge analysis partial discharge test of the test coil CL in combination with the coupling capacitor 9, and can measure the value of the discharge charge with respect to the applied voltage.

As described above, the method of extracting the partial discharge by the coupling capacitor 9 is suitable for the measurement of the large-capacity test object or the grounded test object, and thus can be used for the measurement of the generator coil or the like. The voltage-charge analysis measuring unit 6 uses the low frequency method in which the variation of the response due to the discharge generation position is small with respect to the distributed constant sample, and if the sample coil CL is different, it is detected according to the capacitance value. Since it is necessary to calibrate the charge because the pulse voltage value that changes, the calibrator 10 is a device that generates a simulated discharge pulse for calibration at that time.

The automatic voltage adjustment unit 5 has a function of adjusting the output voltage of the AC high-voltage power supply unit 7 to a predetermined voltage value in order to apply it to the test coil CL, and the step-up / down operation is performed via the interface unit 3. It can be controlled by a control signal from the control circuit 1.

FIG. 2 is an external perspective view of the insulation test apparatus, in which the automatic voltage adjusting unit 5 is housed in the AC voltage power supply unit 7, the blocking coil 8, the coupling capacitor 9 and the calibrator 10 are the voltage-charge analysis measuring unit. It is stored in 6. A plurality of other insulation test devices 11 are mounted, but they do not necessarily have to be housed in the same rack in this way. However, when performing a plurality of insulation tests, it is easier and more efficient to integrate them in this way.

In the calibration at the time of measurement, the distortion factor plane analysis function unit 4 and the voltage-charge analysis measuring instrument unit 6 perform charge calibration by the control signal from the control circuit 1. Since the CPU calibrates automatically, the control circuit 1 only needs to output a calibration command as an insulation test. On the other hand, since the voltage-charge analysis measurement unit 6 does not have a calibration means inside, it is necessary to generate a simulated discharge pulse by the calibrator 10 and perform charge calibration until the detected pulse voltage value reaches a predetermined value. .

When the calibration is completed, the skewness plane analysis function unit 4 or the voltage-charge analysis measurement unit unit 6 starts operating in response to a control signal from the control circuit 1, which means the start of measurement. Therefore, it is necessary to set the voltage-charge analysis to be started after the distortion degree plane analysis is completed. Of course, this order may be freely selected by an input signal from the operation terminal device 2.

When the skewness plane analysis function unit 4 operates, at the same time, the automatic voltage adjusting unit 5 and the AC high-voltage power supply unit 7 also start operating, and apply a predetermined test voltage to the test coil CL. The test circuit voltage is adjusted in advance by the control circuit 1 by the control circuit 1 so that the test voltage value becomes a plurality of predetermined values corresponding to the rated voltage E of the test coil CL. The measurement is automatically performed by the internal CPU of the skewness plane analysis function unit 4, and the maximum discharge charge q
Each data of max and the skewness S of the cycle average φ-q distribution is transferred to the control circuit 1. Since the control circuit 1 creates a graph chart or table based on the captured data and outputs it to the operation terminal device 2, the test result can be displayed in the form of a graph diagram or table by operating the operation terminal device 2 several times. Obtainable.

Even when the voltage-charge analysis measuring instrument unit 6 operates, the voltage automatic adjustment unit 5 and the AC high-voltage power supply unit 7 start operating at the same time, but the test voltage is continuously changed by the voltage automatic adjustment unit 5 from the start voltage value. The voltage is stepped up to a predetermined maximum applied voltage value at a constant speed, and when the predetermined maximum applied voltage value is reached, the voltage is continuously stepped down to a start voltage value at a constant speed. The starting voltage value and the predetermined maximum applied voltage value may be determined in accordance with the rated voltage E of the test coil CL, and the discharge charge is measured at predetermined time intervals during the step-up / down of the applied voltage. Done,
The measurement data is transferred to the control circuit 1. The measurement data taken into the control circuit 1 is output to the operation terminal device 2 in the form of a graph and a table as in the case of the strain plane analysis.

Next, detailed operation of the control circuit 1 for realizing such operation will be described with reference to a personal computer as the control circuit 1, a personal computer input keyboard 2a as the operation terminal device 2, a monitor display 2b, and a printer 2.
An example using c and the plotter 2d will be described with reference to the flow charts of FIG.

The flow chart of FIG. 3 shows a measurement program for the partial discharge test, which is activated when a measurement program execution start signal is input from the keyboard 2a to the control circuit 1. First, in step 100, it is possible to select whether or not to calibrate the discharge charge of the distortion plane analysis function section 4 and the voltage-charge analysis measuring instrument section 6 by inputting from the keyboard 2a, and if not calibrating, step 102 Jump to. The calibration is performed in step 101 for both the strain plane analysis function unit 4 and the voltage-charge analysis measurement unit 6, and the calibration method is as described above.

In the following step 102, the measurement phase of the test coil CL is selected and, for example, the function key f6 of the keyboard 2a is pressed to 3
If you set f7 as the U phase, f8 as the V phase, and f9 as the W phase by pressing the function keys f6 to f9 from the keyboard 2a, you can select the corresponding measurement phase in steps 103 to 106. It is possible to create a data file with a predetermined extension depending on the measurement phase by inputting the file name from the keyboard 2a. As the extension of the data file name, CV indicating the partial discharge test and the initials of the measurement phase are set, and CVB for the three phases, CVU for the U phase, CVV for the V phase, and CVW for the W phase are set. This is convenient for file management because the type of insulation test and measurement phase can be known just by looking at the extension.

In the next step 107, it is judged whether or not a file having the same name as the created data file is already registered in the recording medium such as a floppy disk, and if it is not registered, the process jumps to step 109. On the other hand, if it has been registered, the process proceeds to step 108, and it is possible to determine whether or not to perform the measurement by inputting from the keyboard 2a. When the measurement is stopped, the measurement program ends, and when the measurement is performed, the process proceeds to step 109.

In step 109, the voltage-charge analysis measuring instrument section 6 starts operation, and in the following step 110, when the CR key of the keyboard 2a is input, in the next step 111, the AC high-voltage power supply section 7 starts operating and the test coil CL The supply of the applied voltage to the device starts.
In the following step 112, after waiting about 5 seconds until the circuit becomes stable, the process proceeds to step 113, and continuous voltage boosting by the voltage automatic adjustment unit 5 is started. In the next step 114, the measurement data is taken into the control circuit 1 every 5 mS, but the actual effective data is the applied voltage of 100 V.
Since it is an integer multiple of 100V, that is, when it becomes a unit of 100V, in the following step 115, it is determined whether or not the acquired data is valid data. If it is not valid data, the flow returns to step 114 to take in the data again. On the other hand, if it is valid data, the flow proceeds to step 116 to display the voltage and discharge charge values on the screen of the monitor display 2b.

In the next step 117, if the applied voltage does not reach the maximum voltage Vmax, the process returns to step 114 to capture the data again, and if it reaches the maximum voltage Vmax, the process proceeds to step 118 and the automatic voltage adjustment unit The boosting by 5 is stopped and the maximum applied voltage Vmax is maintained for about 1 minute. Further, when the applied voltage is stepped down to the initial voltage by the voltage automatic adjustment unit 5 in step 117, the process also proceeds to step 118 to stop the voltage reduction by the voltage automatic adjustment unit 5. Continued Step 11
In 9, when the applied voltage reaches the maximum voltage Vmax, the process proceeds to step 120, where the automatic voltage adjusting unit 5 continuously reduces the voltage,
Returning again to step 114, data is taken in.

On the other hand, if the voltage has already been stepped down and the applied voltage has become the initial voltage, the operation proceeds to step 121, and the operation of the voltage-charge analysis measuring instrument unit 6 is stopped. In the next step 122,
The relationship between the discharge charge amount and the applied voltage value based on the measurement data is displayed in the form of a table and a graph on the screen of the monitor display 2b. Fig. 4 is an example of the graph, and the maximum applied voltage Vmax is on the graph. Then, let the rated voltage of the test coil CL be E
Then, Vmax = [1.25 · E / 3 ^1/2 ] is set.

With the above, the automatic measurement of the partial discharge test by the voltage-charge analysis method ends, but in the next step 123, it is possible to select whether or not to perform the measurement by the skewness plane analysis method by inputting from the keyboard 2a. When the measurement by the skewness plane analysis method is not performed, it is selected from the keyboard 2a whether to jump to step 135 and register the data in a recording medium such as a floppy disk. If not registered, the measurement program is directly terminated, and if registered, the data is held in step 136 and then the measurement program is terminated. The data file name at that time is the file name created in steps 103 to 106.

On the other hand, when performing the measurement by the strain rate plane analysis method in step 123, the process proceeds to the next step 124, the strain rate plane analysis function unit 4 starts operating, and in the following step 125, the CR key of the keyboard 2a is input. Then, the measurement is started. In the next step 126, boosting of the applied voltage by the automatic voltage adjusting unit 5 starts, and in the following step 127, step 12 is performed until the first predetermined applied voltage value V1 = [E / 3 ^1/2 ] is reached.
Return to 6 and continue boosting. When the first predetermined applied voltage value V1 is reached in step 127, the process proceeds to step 128, where the information necessary for measurement and data analysis such as the type of measurement data and data sampling time is sent from the control circuit 1 to the strain plane. The data is transferred to the built-in CPU of the analysis function unit 4, and the measurement is automatically performed. In the following step 129, the measured maximum discharge charge amount qmax and the data of the cycle average φ-q distribution are fetched by the control circuit 1 and displayed on the screen of the monitor display 2b.

In the next step 130, boosting of the applied voltage by the automatic voltage adjusting unit 5 starts again, and in step 131, the process returns to step 130 until the second predetermined applied voltage value V2 = [1.25 · E / 3 ^1/2 ] is reached. Boosting is continued. When the second predetermined applied voltage value V2 is reached in step 131, the information necessary for the measurement and data analysis is again sent from the control circuit 1 to the built-in CPU of the skewness plane analysis function unit 4 in step 132 as in step 128. It is transferred and the measurement is done automatically.

In step 133, the measured maximum discharge charge amount qmax and the data of the cycle average φ-q distribution are transferred to the control circuit 1 and displayed on the screen of the monitor display 2b. Then, in step 134, the operation of the skewness plane analysis function unit 4 is stopped, and in the same way as in the case where the measurement by the above-described strainness plane analysis method is not performed in steps 135 and 136, the data is recorded on a recording medium such as a floppy disk. Register and complete the measurement program.

To create a report, in step 200 of the flow chart shown in FIG. 5, a list of file names of data files already registered in the recording medium such as a floppy disk is displayed on the screen of the monitor display 2b. To be done. In the following step 201, the file name of the data file for which the report is to be created is entered from the keyboard 2a. In step 202, based on the measurement data of the input data file, for the data by the voltage-charge analysis method, the discharge start voltage and the discharge extinction voltage and the slope Nq of the maximum discharge charge amount are calculated, and the skewness plane analysis method is used. With respect to the data of (1), since the data which has already been analyzed by the built-in CPU of the strain degree plane analysis function unit 4 is contained in the data file, the control circuit 1 does not need to perform the calculation for the data analysis.

Regarding the voltage-charge analysis method, in the subsequent step 203, in addition to the change Nq of the discharge start voltage and the discharge extinction voltage and the maximum discharge charge amount calculated in step 202, the change of the discharge charge amount Q with respect to the applied voltage V is shown. The table and graph shown are also output from the plotter 2d. On the other hand, in the strain degree plane analysis method, the maximum discharge charge amount qmax and the positive and negative strain degrees are tabulated and graphed and output from the plotter 2d.

As shown in Fig. 4, the discharge start voltage is calculated by averaging the discharge charge measured every 200V from the measured discharge charge at every 100V and increasing the value to 1.8 times the minimum discharge charge average value. The discharge extinction voltage is the applied voltage value when the average value similarly obtained when the applied voltage is lowered becomes 1 / 1.8 of the maximum discharge charge amount average value.

In addition, the slope Nq of the maximum discharge charge amount is qm2, which is the discharge charge amount at a predetermined applied voltage [E / 3 ^1/2 ] at the time of boosting, and the maximum predetermined applied voltage [1.25 · E / 3 ^1/2 ] at the time of boosting. The discharge charge amount at
The qml is calculated using the following equation, Nq = | 10log (qm2 / qm1) |.

This inclination Nq serves as a criterion for determining the degree of insulation deterioration of the winding coil, and the inclination Nq decreases as the insulation deterioration increases.

Next, in step 204, if there is another data file for which a report should be created, it is possible to return to step 200 by an input signal from the keyboard 2a, and if there is no data file for which a report is to be created, The report writing program can be terminated by inputting from the keyboard 2a.

The report creating program according to the flow chart shown in FIG. 5 described above may be automatically started when the measurement program shown in FIG. 3 is finished, but as shown in FIG. It is efficient to make a menu program. If a work item is selected in step 50 of FIG. 6 and, for example, the numeric keypad “1” on the keyboard 2a is measured, “2” is created as a report, and “3” is set to end, the numeric keypad will be used to call. You can select the program.

That is, if the ten key "1" is input, the measurement program shown in FIG. 3 is started in step 51, and if the ten key "2" is input, the report preparation program shown in FIG. 5 is started in step 52. When each program ends, the process returns to step 50 to select a work item. Here, if you enter the ten key "3", the step
At 53, the whole program ends. If you create such a menu program, if you install another insulation test device 11 in the insulation test device by this partial discharge method,
It is efficient because it only needs to add another measurement program and report writing program as work items.

In this way, since the insulation test can be automatically performed centering on the control circuit 1, not only the measurement time and input can be shortened and the labor can be saved, but also the tester can directly measure the high-voltage measuring device. All that is required is to operate the operation terminal device 2 without touching, and the operability and safety are extremely high. In the past, the measuring equipment used for the partial discharge test was very susceptible to external noise, and it was difficult to adjust and calibrate the equipment, so it was usual for test personnel to require advanced measurement technology and experience. If the control circuit 1 automates the adjustment and calibration of the device, the tester does not need to have a particular technique or experience, so there is no need to entrust a specialized contractor as in the past, and the cost for testing Will also be cheaper.

On the other hand, regarding the evaluation of the measurement results and the preparation of the report, the control circuit 1 automatically outputs the arithmetic processing and the tables and graphs from the operation terminal device 2, so that the work load on the tester is reduced. It Furthermore, if it is possible to connect another insulation test measuring device 11 to the control circuit 1 and the interface section 3, when it is desired to sequentially perform several kinds of insulation tests on the test coil, the wiring and the device can be used. This is convenient because it does not require any changes.

[Advantages of the Invention] As described above, the insulation test apparatus by the partial discharge method according to the first invention can perform not only the measurement by the voltage-charge analysis method but also the measurement by the distortion plane analysis method. It is possible to grasp the condition of insulation deterioration more accurately than the partial discharge test, that is, the strain plane analysis method can predict the magnetism of insulation breakdown that could not be achieved in the past from the measurement results. It is easy to know when to rewind the test coil.

Further, the insulation test apparatus based on the partial discharge method according to the second aspect of the invention makes it possible to determine the insulation deterioration of the sample by obtaining the slope of the maximum discharge charge amount of the sample.

[Brief description of drawings]

The drawings show an embodiment of an insulation test apparatus by the partial discharge method according to the present invention, and FIG. 1 is an overall block circuit configuration diagram, and FIG.
Figure is an external perspective view, Figure 3 is a flow chart of the measurement program, Figure 4 is a graph of an example of test results, Figure 5 is a flow chart of the report preparation program, and Figure 6 is a flow chart of the menu program. is there. Reference numeral 1 is a control circuit, 2 is an operation terminal device, 2a is a keyboard, 2b is a monitor display, 2c is a printer, 2d is a plotter, 3 is an interface part, 4 is a distortion plane analysis function part, and 5 is automatic voltage. Adjusting unit, 6 voltage-charge analysis measuring unit, 7 AC high-voltage power supply unit, 8 blocking coil,
Reference numeral 9 is a coupling capacitor, 10 is a calibrator, and 11 is another insulation measuring device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuki Okamoto 3-12-12 Sagamihara, Sagamihara City, Kanagawa Prefecture (72) Inventor Shinatsu Terao 3-4-1 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Cable Co., Ltd. Tokyo office (72) Inventor Mihaku Tsunoda 1008 Shinbori, Kumagaya-shi, Saitama Mitsubishi Cable Industries, Ltd. Kumagaya Works (72) Inventor Akio Miura 1008 Shinbori, Kumagaya-shi, Saitama Mitsubishi Cable Industries, Ltd. Kumagaya Works (72) ) Inventor Hiro Hara, 1008, Shinbori, Kumagaya, Saitama Mitsubishi Cable Industries, Ltd., Kumagaya Manufacturing Co., Ltd. (56) References Okamoto and Tanaka: "Void defects and correlations between statistical properties of partial discharge pulse groups (▲ I ▼ ), Denchu Kenpo, No. 179030 (Sho 55) Okamoto, Tanaka: “Correlation between void defects and statistical properties of partial discharge pulse groups. (▲ II ▼), Denchu Kenpo, No. 180005 (Sho 55) Okamoto, Tanaka: “Cycle average φ-q characteristics of partial discharge”, IEEJ Transactions A, 57-A 49, Vol 102, No. 7, PP. 7-14 (57) Okamoto, Tanaka: "Change of pulse mean φ-q distribution pattern due to progress of treeing", IEEJ Transactions A, 57-A84, Vol 102, No. 12, PP. 37-44 (57) Ikeda, Sunada: "Method for determining insulation deterioration of generator windings by slope Nq of maximum discharge charge-voltage characteristic", Institute of Electrical Engineers, Insulation Material Study Material EIM-76-40 (1976)

Claims (3)

[Claims] 1. A control circuit for connecting an operation terminal device to control the entire apparatus, and an insulating state of a test piece connected to the control circuit via an interface part and based on a discharge charge amount with respect to an applied voltage. The voltage-charge analysis function unit, which is directly connected to the control circuit, is used to analyze the insulation state of the specimen by the degree of distortion based on the partial discharge pulse generation phase φ and the cycle average φ-q distribution obtained from the discharge charge q. And a voltage automatic adjustment unit that adjusts and outputs the voltage from the AC high-voltage power supply unit, and the voltage-charge analysis function unit and the skewness plane analysis function unit are the voltage automatic adjustment unit. An insulation test apparatus by the partial discharge method, characterized in that the test piece is connected to the automatic voltage adjusting section, the voltage-charge analyzing function section, and the distortion degree plane analyzing function section. 2. A control circuit for connecting an operation terminal device to control the entire apparatus, a voltage-charge analysis function section connected to the control circuit via an interface section, and a voltage from an AC high-voltage power supply section. The voltage-charge analysis function unit, which is composed of a voltage automatic adjustment unit that adjusts and outputs the voltage-charge analysis function unit connected to the voltage automatic adjustment unit and the sample, is a maximum applied voltage in a step-up process by the voltage automatic adjustment unit. The discharge charge amount of the sample is measured with respect to the voltage value and the second voltage value which is lower than the first voltage value by a constant voltage, and the slope of the maximum discharge charge amount of the sample is calculated by the ratio of these discharge charge amounts. Insulation test device by partial discharge method characterized by seeking. 3. The insulation according to the partial discharge method according to claim 1 or 2, wherein the voltage-charge analysis function section comprises a blocking coil, a coupling capacitor, a calibrator, and a voltage-charge analysis measurement section. Test equipment.