JP3562133B2 - Electrical equipment insulation diagnostic equipment - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for diagnosing insulation performance of an electric device.
[0002]
[Prior art]
It is known that when the insulation performance of electrical equipment such as a gas insulated switchgear is degraded for some reason, partial discharge occurs as a predictive phenomenon before an arc flash accident occurs. The electrical equipment insulation monitoring device is intended to detect this partial discharge at a minor stage, thereby preventing an arc flash accident in the electrical equipment.
[0003]
As means for detecting the partial discharge, detection of an electromagnetic wave generated by the partial discharge is performed. As a specific configuration, antennas are arranged at a plurality of places where partial discharge of an electric device is likely to occur, and the output of each antenna is input to the determination device via a selector.
The determination device selects one measurement channel by switching the selector, and determines the presence or absence of partial discharge from a signal detected by an antenna connected to the measurement channel. Thereafter, the determination device switches the selector to determine the presence or absence of the partial discharge for each measurement channel, and performs the insulation diagnosis of the electric device.
[0004]
In an electrical equipment insulation diagnostic apparatus having a plurality of measurement channels, an antenna may be connected to only some of the plurality of measurement channels. In this case, in order to reduce the time required for the diagnosis, a measurement channel on which the determination device performs an insulation diagnosis, that is, a measurement channel to which an antenna is connected is specified to the determination device.
As a conventional method of specifying the measurement channel to be used, (1) a measurement channel used by a designer or a user is specified in advance in a nonvolatile memory by a program. (2) A measurement channel is set on a setting input screen of the diagnostic apparatus. (3) The diagnostic device is provided with a switch for setting the measurement channel, and the user specifies with the switch.
[0005]
[Problems to be solved by the invention]
In the above-described conventional measurement channel setting method, every time the measurement channel is changed, erasing / writing of the ROM, screen setting, switch operation, and the like must be performed. This makes the operation cumbersome and causes a setting error or the like.
SUMMARY OF THE INVENTION An object of the present invention is to make it possible to automatically set a measurement channel to which an antenna is connected in an electrical equipment insulation diagnostic apparatus having a plurality of measurement channels.
[0006]
[Means for Solving the Problems]
The present invention has been made to achieve the above object, and has a plurality of measurement channels, and determines whether or not partial discharge has occurred in an electric device based on a detection signal of an antenna connected to the measurement channels. The present invention is directed to an electrical equipment insulation diagnostic device including a determination unit.
[0007]
In the first aspect of the present invention, after the determination unit is connected to the antenna, the determination unit sequentially switches the measurement channel and determines whether a broadcast wave is received on the measurement channel. Here, when it is determined that the broadcast wave has been received, the antenna is connected to the measurement channel. Therefore, the measurement channel selected at that time is set as a measurement channel used for insulation diagnosis.
[0008]
The determination unit performs an insulation diagnosis of the electric device using the signal obtained from the set channel.
In the second embodiment of the present invention, a simulation signal is detected instead of detecting a broadcast wave. Therefore, a simulation signal generator and a simulation signal transmission antenna are provided, and a simulation signal is transmitted from the simulation signal transmission antenna.
[0009]
The determination unit sequentially switches the measurement channel, and determines whether or not the simulation signal is received in the signal of the measurement channel. When it is determined that the simulation signal has been received, the measurement channel is set as a measurement channel used for insulation diagnosis.
According to the present invention, a measurement channel used for insulation diagnosis is automatically set only by connecting the determination unit of the electrical equipment insulation diagnosis device and the antenna. Thus, the insulation diagnosis is performed only for the measurement channel to which the antenna is connected, so that the time required for the diagnosis can be reduced.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 shows a state in which the insulation diagnostic device is applied to electric equipment.
In the figure, reference numeral 1 denotes an electric device such as a gas insulated switchgear, a cubicle, a gas circuit breaker, and the like. Reference numeral 2 denotes a partial discharge generated inside the electric device 1 due to insulation abnormality. When the partial discharge 2 occurs, an electromagnetic wave 3 including a certain frequency component is generated. Receiving antennas 41 and 42 are arranged at positions where partial discharge 2 is to be detected. Output signals from the receiving antennas 41 and 42 are input to the determination device 6 through the selector 5.
[0011]
Reference numeral 7 denotes a transmission antenna for transmitting a television terrestrial wave 8. At present, there are 64 terrestrial television channels in Japan, but the number of receivable channels differs depending on the area. The receiving antennas 41 and 42 detect not only the electromagnetic wave 3 due to the partial discharge 2 but also the electromagnetic wave 8 transmitted from the transmitting antenna 7. In this example, a terrestrial television wave is used as a broadcast wave, but a radio wave, a frequency band of mobile communication, a satellite wave, or the like can also be used.
[0012]
FIG. 2 is a diagram illustrating a configuration of the insulation diagnosis device.
41 to 43 are receiving antennas. Each output signal of the receiving antennas 41 to 43 is input to each input terminal of the selector 5. The signal output from the selector 5 is amplified by the preamplifier 61 of the determination device 6 and input to the tuner 62. The tuner 62 sets a tuning frequency under the control of the CPU 63 and outputs a detected signal to the CPU 63. The CPU 63 switches the tuning frequency of the tuner 62 and switches the selector 5 via the I / O interface 64.
[0013]
The determination device 6 is formed to be portable and connected to the receiving antennas 41 to 43 when performing insulation diagnosis. The selector 5 may be connected to the receiving antennas 41 to 43 at all times and connected to the determination device 6 at the time of insulation diagnosis, or the selector 5 may be incorporated into the determination device 6 to perform insulation diagnosis. Sometimes, it may be connected to the receiving antennas 41 to 43.
[0014]
The operation of the determination device 6 will be described with reference to the flowchart of FIG.
In step S11, the detection frequency of the tuner 61 is set to the measurement channel setting frequency. In this example, the measurement channel setting frequency is a television broadcast frequency. In Japan, there are 64 channels of television broadcast waves, so these 64 frequencies are set here.
[0015]
When the process proceeds from step S12 to step S13, the selector 5 is switched to select one measurement channel, and the process proceeds to step S14.
In step S14, it is determined whether a television broadcast wave has been received on the selected measurement channel. Here, the tuner 62 is sequentially switched to detect all the frequencies of the 64 channels, and it is checked whether a signal exceeding a certain level is obtained for each frequency. When a signal exceeding a certain level is obtained in a predetermined number (eg, 3) of the 64 channels, it is determined that the measurement channel has received a broadcast wave, that is, a reception antenna is connected to the channel. A determination is made, and in step S15, the channel is set as a channel used for insulation diagnosis. If no reception has been performed, it is determined that no reception antenna is connected to the channel, and the process returns to step S12.
[0016]
When the operations of steps S12 to S15 described above are repeated and all the measurement channels, that is, the inputs of all the selectors 5 are checked, the process proceeds from step S12 to step S21, and it is determined whether there is a partial discharge.
In step S21, the tuner 61 is set to the frequency for insulation diagnosis. As the frequency for insulation diagnosis, a frequency used for insulation diagnosis using normal electromagnetic waves is set. For example, a frequency of about 100 is selected from the frequency range of the electromagnetic wave 3 due to the partial discharge 2, and this frequency is set in the tuner 61.
[0017]
In step S23 via step S22, the selector 5 is switched to select one of the measurement channels for insulation diagnosis set in step S14.
In step S24, the presence or absence of partial discharge is determined for the measurement channel. Various known methods can be adopted as this diagnostic method. For example, detection is performed for 100 frequencies set in the tuner 61 in step S21, and the average of the signal level for each frequency is obtained. Then, when the average value exceeds the set value, it is determined that partial discharge 2 has been detected in the measurement channel, and when it does not exceed, it is determined that there is no insulation abnormality.
[0018]
Next, returning to step S22, the selector 5 is switched to the next measurement channel in step S23. Thereafter, the processing of steps S22 to S24 is repeated, and the presence or absence of partial discharge is determined for all of the insulation diagnosis measurement channels set in step S14.
When the determination has been completed for all the insulation diagnosis measurement channels, the process proceeds from step S22 to step S25, where the presence or absence of a partial discharge is displayed for each insulation diagnosis measurement channel, and the process ends.
[0019]
According to this example, the determination device 6 of the insulation diagnosis device automatically sets the measurement channel to which the receiving antenna is connected as the measurement channel used for insulation diagnosis, and uses only the measurement channel to determine whether there is partial discharge. Is determined. Therefore, the operation of setting the measurement channel to be used as in the related art can be omitted.
Further, the insulation diagnosis is not performed on the measurement channel to which the receiving antenna is not connected, so that the required time can be reduced.
[0020]
Furthermore, in this example, the antenna circuit can be checked by displaying the measurement channel set for insulation diagnosis. In other words, when the measurement channel to which the antenna is connected is not set as the measurement channel to be used, the antenna, the antenna cable, the connector, and the like of the measurement channel have poor contact, poor sensitivity, and the like.
[0021]
(Embodiment 2)
A second example of the present invention will be described with reference to the drawings.
FIG. 4 shows a state in which the insulation diagnostic device of the present example is applied to electric equipment.
In FIG. 4, reference numeral 11 denotes a simulation signal generator, and reference numeral 12 denotes a simulation signal transmitting antenna. The simulated signal generator 11 generates a simulated signal having a frequency different from that of a broadcast wave of a television or a radio, and transmits a simulated signal from the simulated signal transmitting antenna 12. Note that the simulation signal generator 11 can be incorporated in the determination device 6. Further, not only one simulation signal transmission antenna 12 but also a plurality of simulation signal transmission antennas 12 can be provided. Other configurations are the same as those in FIG. 1 described above, and a description thereof will not be repeated.
[0022]
The configurations of the antennas 41 to 43, the selector 5, and the determination device 6 of this example are shown in FIG. The description of FIG. 2 has been already described in the description of the first embodiment.
The operation of the determination device of this example will be described with reference to the flowchart of FIG.
In step S11, the tuner is set to the measurement channel setting frequency. In this example, the same frequency as the frequency of the simulation signal generated by the simulation signal generator 11 is set.
[0023]
When the process proceeds from step S12 to step S13, the selector 5 is switched to select one measurement channel, and the process proceeds to step S14.
In step S14, the presence or absence of reception is determined. Here, it is determined whether or not a simulation signal has been received by determining whether or not a prescribed frequency, signal level, and pattern have been obtained from the measurement channel. When it is determined that the simulation signal has been received, it is determined that the measurement channel is connected to the receiving antenna, and the channel is set as a channel used for insulation diagnosis in step S15. If it is determined that the simulation signal has not been received, it is determined that the receiving antenna is not connected to the channel, and the process returns to step S12.
[0024]
Subsequent operations are the same as in the first embodiment.
This example has the same effect as the above-described first embodiment. However, compared to the first embodiment, since an existing broadcast wave is not used, automatic setting is possible even in a mountainous area or at night where it is difficult to receive the broadcast wave. It has the feature that it becomes.
[0025]
【The invention's effect】
According to the present invention, a measurement channel to which an antenna is connected can be automatically set in an electrical equipment insulation diagnostic apparatus having a plurality of measurement channels. Since the insulation diagnosis can be performed only on the measurement channel to which the antenna is connected, the time required for the diagnosis can be reduced.
[Brief description of the drawings]
FIG. 1 is a diagram showing a use state of an insulation diagnosis device according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a specific configuration of an insulation diagnosis device of the present invention.
FIG. 3 is a flowchart for explaining the operation of the insulation diagnostic device of FIG. 2;
FIG. 4 is a diagram illustrating a use state of an insulation diagnosis device according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electric equipment 2 ... Partial discharge 3 ... Electromagnetic waves 41, 42, 43 ... Receiving antenna 5 ... Selector 6 ... Judgment device 61 ... Preamplifier 62 ... Tuner 63 ... CPU
64 I / O interface 7 transmitting antenna 8 television terrestrial wave 11 simulated signal generator 12 simulated signal transmitting antenna

Claims (3)

An electrical equipment insulation diagnostic apparatus having a plurality of measurement channels and including a determination unit that determines whether partial discharge has occurred in the electrical equipment based on a detection signal of an antenna connected to the measurement channel,
The determination unit includes a unit that switches the measurement channel, a unit that determines whether a predetermined broadcast wave is received on the measurement channel, and, when the unit determines that the predetermined broadcast wave is received, the measurement unit performs the measurement. Means for setting the channel as a measurement channel used for insulation diagnosis,
The electrical device insulation diagnostic device, wherein the determination unit performs an insulation diagnosis using a signal obtained from the set measurement channel when performing the insulation diagnosis of the electrical device. The electrical equipment insulation diagnostic device according to claim 1, wherein the broadcast wave is a television broadcast wave. An electrical equipment insulation diagnostic apparatus having a plurality of measurement channels and including a determination unit that determines whether partial discharge has occurred in the electrical equipment based on an output signal of an antenna connected to the measurement channel,
A simulation signal transmitting antenna, and means for transmitting a simulation signal from the antenna are provided,
Means for switching the measurement channel, means for determining whether or not the simulation signal has been received in the measurement channel, and when this means determines that the simulation signal has been received, the measurement channel Means for setting as a measurement channel used for insulation diagnosis,
The electrical device insulation diagnostic device, wherein the determination unit performs an insulation diagnosis using a signal obtained from the set channel when performing the insulation diagnosis of the electrical device.

Images