JP2004226300A - Deterioration diagnostic apparatus and method for rotating electric machine - Google Patents

Abstract

An object of the present invention is to accurately perform deterioration diagnosis of a rotating electric machine regardless of the type of the rotating electric machine.
An impulse voltage generator applies an impulse voltage between power terminals of a rotating electric machine through a test line. At this time, when a void discharge occurs in the winding part of the rotating electric machine, a high-frequency current flows through the test line 2. The current transformer 4 measures a high-frequency current flowing through the test line 2, and supplies the measured output to an A / D conversion module 6 through a high-pass filter 5. The voltage converter 7 reduces the impulse voltage applied to the test line 2 to a voltage level that can be input to the A / D conversion module 6. The personal computer 8 displays, on a monitor, an output waveform of the current transformer 4 output through the high-pass filter 5 and an output waveform of the voltage converter 7 based on a digital signal input from the A / D conversion module 6. By observing and comparing these waveforms, the degree of deterioration of the windings of the rotating electric machine 1 is determined.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a deterioration diagnosis device and a deterioration diagnosis method for determining the degree of deterioration of a rotating electric machine while the rotating electric machine is disconnected from a power supply.
[0002]
[Prior art]
In a rotating electrical machine using windings, the insulation of the windings deteriorates with time due to various deterioration factors such as heat, mechanical force, voltage, and environmental conditions, and it is inevitable that the insulation eventually decreases. When such insulation degradation occurs, it is necessary to perform maintenance such that the entire device is replaced or only the winding is replaced according to the degree of deterioration of the winding. However, in practice, it is extremely difficult to judge the deterioration of the windings of the rotating electric machine from the appearance, so it is known that the windings of the rotating electric machine have deteriorated only after the rotating electric machine has been burned due to a decrease in winding insulation. Often. In order to cope with such a situation, conventionally, the deterioration of the windings of the rotating electrical machine is detected by the following method, and the replacement time is determined.
[0003]
The first method is to determine a replacement time for each device or a winding by estimating in consideration of a service life estimated in advance and an environment and a use condition of an installation place when manufacturing a rotating electric machine, and A method of replacing equipment or windings before burning of a rotating electric machine occurs.
[0004]
The second method is to sample a deterioration investigation sample from a rotating electric machine whose environment and operating conditions are almost the same, and perform various breakdown tests (measurement of breakdown voltage, etc.) on the sampled winding of the rotating electric machine, A method of determining the degree of deterioration of the winding based on the test results and determining the replacement time.
[0005]
The third method is to periodically stop the rotating electric machine, perform a non-destructive test on the insulation state of the windings of the rotating electric machine such as insulation resistance, dielectric loss tangent, and polarization index, and measure the insulation state. Method for predicting the deterioration state of the winding and the time of occurrence of burnout based on the data.
[0006]
However, among the above-mentioned conventional methods, the first method is based solely on the estimation, and therefore, it is possible to avoid a deviation from the actual use condition and the condition assumed due to individual differences of the rotating electric machine. Absent. In this case, the assumed conditions are generally assumed to be strict conditions in consideration of safety. For this reason, it is easy to judge that the service life of the rotating electric machine is shorter than the service life that can be actually used. Economy. Conversely, if the use conditions are more severe than the assumed conditions, there is a problem that the deterioration during use progresses early and a failure occurs earlier than expected.
[0007]
In the second method, the degree of deterioration of the sampled winding can be determined relatively accurately, and the replacement time can be determined relatively accurately. However, since the windings subjected to the destructive test cannot be reused, the degree of deterioration of the windings cannot be diagnosed for all rotating electric machines. In addition, there is a problem that the deterioration diagnosis by the destructive test requires much time and cost.
[0008]
In the third method, when the rotating electric machine is stopped, it is necessary to disconnect the wiring of each rotating electric machine and perform a nondestructive test individually, so that much labor is required for measuring the insulation state. Also, because the measured value is affected by environmental conditions such as the dryness of the air at the time of the measurement, and the influence of contaminants adhering to the windings during operation of the rotating electric machine is increased, correct evaluation of the measured value is required. There are times when you can't.
[0009]
As a method for solving such a problem, conventionally, various methods have been proposed which can investigate the insulation state of the rotating electric machine while online. For example, a method of measuring moisture absorption that greatly affects the electrical properties of the rotating electrical machine winding online (for example, refer to Patent Document 1), or a method of online measuring the surface insulation state of a device using a simulated electrode (for example, see Patent In addition, there is a method in which gas generated in a rotating electric machine is measured online by a gas sensor, and a discharge is measured online by an optical sensor (for example, see Patent Document 3).
[0010]
[Patent Document 1]
JP-A-63-59748
[Patent Document 2]
JP-A-2-227675
[Patent Document 3]
Japanese Utility Model Laid-Open No. 4-63045
[Problems to be solved by the invention]
However, among the methods described in the above-mentioned publications, the method of online measuring the moisture absorption of the windings of the rotating electric machine and the method of online measuring the surface insulation state of the device with the simulated electrode are based on the measured values and the rotating electric machine itself. There is a case where the correlation with the insulation state is poor, and the reliability of the measurement result is low. In addition, the measurement method using a gas sensor or optical sensor can be used to detect deterioration of the rotating electrical machine itself, but it is effective to install it on a fully closed rotating electrical machine that is relatively unaffected by the environment and whose life can be easily predicted. There is a problem that it is difficult to install an open type in which the degree of deterioration changes abruptly due to environmental influences.
[0014]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a rotating electric machine deterioration diagnosis apparatus and deterioration diagnosis capable of accurately performing deterioration diagnosis of a rotating electric machine regardless of the type of the rotating electric machine. It is to provide a method.
[0015]
[Means for Solving the Problems]
The impulse voltage generator for applying an impulse voltage through a test line between power supply terminals of an electric rotating machine to be diagnosed for degradation in order to achieve the above object is provided by the impulse voltage generator according to claim 1 and the test. A high-frequency current sensor provided so as to capture the high-frequency current flowing through the wire, and an observation device capable of observing the high-frequency current captured by the high-frequency current sensor, and further comprising the impulse between power terminals of the rotating electric machine. An impulse voltage is applied from a voltage generator, and at this time, a high-frequency current captured by the high-frequency current sensor is observed by the observation device to determine a degree of deterioration of windings of the rotating electric machine. .
[0016]
In a general low-voltage rotating electric machine, a varnish treatment is performed mainly for fixing the winding so as not to move due to electromagnetic vibration or the like during operation. In general, a resin composed of a high-molecular organic material is used for this type of varnish. However, a varnish made of such a material is partially oxidized or reduced due to heat during operation of the rotating electric machine. It scatters with a molecular weight, and the scattered portions become voids in the resin. When an electric field is applied to the dielectric around the void, a discharge is generated at a relatively low electric field (a so-called void discharge), which causes discharge deterioration.
[0017]
Generally, when an impulse voltage is applied to a winding of a rotating electrical machine, the applied voltage attenuates and vibrates due to the inductance and the stray capacitance of the winding. At this time, if a void exists in the varnish around the winding, a void discharge occurs in that portion, and the voltage applied before the discharge changes to zero. An order of high-frequency current flows. Therefore, if the high-frequency current generated by the discharge is captured, the deterioration of the rotating electric machine can be diagnosed.
[0018]
According to the first aspect of the present invention, when a void discharge occurs in the winding portion of the rotating electric machine in response to applying the impulse voltage from the impulse voltage generating device through the test line between the power supply terminals of the rotating electric machine, The high-frequency current flowing through the test line due to the void discharge is captured by the high-frequency current sensor. The high-frequency current captured in this manner can be observed by an observation device, and the degree of deterioration of the rotating electric machine is determined based on the observation. Since such means measures changes in electrical characteristics due to the generation of voids due to thermal degradation, it can be applied to most rotating electrical machines regardless of the type of rotating electrical machine (fully closed type, open type, etc.). Become. That is, the deterioration diagnosis of the rotating electric machine can be accurately performed regardless of the type of the rotating electric machine.
[0019]
In this case, a high-pass filter having a frequency band of an oscillating current accompanying the application of the impulse voltage as an attenuation region may be interposed between the high-frequency current sensor and the observation device. it can.
The high-frequency current sensor captures a component of an oscillating current generated when an impulse voltage is applied between the power supply terminals of the rotating electric machine, in addition to the high-frequency current associated with the void discharge. According to this, the oscillating current accompanying the application of the impulse voltage is attenuated by the high-pass filter. Therefore, in the high-frequency current sensor, a high-frequency current due to void discharge, that is, a high-frequency current at a level much smaller than an oscillating current due to the application of an impulse voltage can be captured with high sensitivity. , The degree of deterioration of the rotating electric machine can be accurately determined.
[0020]
As in the means according to claim 3, a voltage conversion device for reducing the impulse voltage applied from the impulse voltage generator to the test line and applying the voltage to the observation device is provided. A configuration may be adopted in which the impulse voltage waveform provided from the voltage converter is output in a state that can be compared with the high-frequency current waveform captured by the high-frequency current sensor.
When an impulse voltage is applied between the power supply terminals of a rotating electrical machine that is in a state where void discharge occurs in the winding part, the impulse voltage oscillates, causing a plurality of void discharges, and the high frequency generated with each void discharge Current is captured in a high frequency current sensor. In this case, there is a high possibility that the captured high-frequency current includes switching noise in the impulse voltage generator, and thus it is necessary to exclude such a captured high-frequency current from the determination target of the degree of deterioration of the winding. is there. In the means according to claim 3, the applied impulse voltage is stepped down by the voltage converter and applied to the observation device. In the observation device, the applied impulse voltage waveform is compared with the high-frequency current waveform captured by the high-frequency current sensor. It is configured to output in a comparable state. Therefore, based on the comparison between the two waveforms, the high-frequency current waveform that may include switching noise in the impulse voltage generator can be easily excluded from the determination target of the degree of deterioration of the winding. Thus, the accuracy of determining the degree of deterioration of the winding is improved.
[0021]
As in the means according to claim 4, the observation device extracts a component near a phase at which the impulse voltage waveform crosses zero, from the high-frequency current component captured through the high-frequency current sensor, and extracts the extracted high-frequency current component. The configuration may be such that the degree of deterioration of the windings of the rotating electric machine is determined based on this.
According to this configuration, of the high-frequency current components captured through the high-frequency current sensor, a component in a period near the phase where the impulse voltage waveform crosses zero, that is, a component in a period in which the switching noise generated by the impulse voltage generator converges Since the degree of deterioration of the windings of the rotating electric machine is determined based on this, the deterioration diagnosis can be performed without being adversely affected by the switching noise.
[0022]
In the case where the impulse voltage generator is configured to generate the impulse voltage during a period from when the built-in switching element is turned on to when the impulse voltage is turned off, as in the means according to claim 5, A determination function of removing high-frequency current captured through the high-frequency current sensor as noise within a set time from each time of turning on and off the built-in switching element, and observing high-frequency current captured at other voltage phases. The configuration may be such that the degree of deterioration of the windings of the rotating electric machine is determined based on the determination.
In general, in an impulse voltage generating device configured to generate an impulse voltage during a period from when the built-in switching element is turned on to when it is turned off, when the impulse voltage is generated, that is, when the built-in switching element is turned on and Since switching noise occurs when the switch is turned off, the noise is superimposed on the high-frequency current captured by the high-frequency current sensor. In this case, in the means according to claim 5, the observation device deletes the high-frequency current captured through the high-frequency current sensor within a set time from each time of turning on and off the built-in switching element as noise, and removes the high-frequency current at other voltage phases. Since the degree of deterioration of the winding of the rotating electrical machine is determined based on the observation of the captured high-frequency current, the accuracy of the determination is improved.
[0023]
7. A method for diagnosing deterioration of a rotating electrical machine according to claim 6, wherein an impulse voltage generator for applying an impulse voltage through a test line between power supply terminals of the rotating electrical machine to be diagnosed to achieve the above object is provided. A high-frequency current sensor provided so as to capture a high-frequency current flowing through a line, a voltage conversion device that steps down an impulse voltage applied to the test line from the impulse voltage generator and supplies the voltage to the observation device, and the high-frequency current sensor And a monitoring device capable of observing the waveform of the high-frequency current captured by and the waveform of the impulse voltage from the voltage conversion device, and in the vicinity of the phase where the impulse voltage waveform observed by the monitoring device crosses zero. The deterioration diagnosis of the rotating electrical machine is performed by observing the waveform of the high-frequency current.
[0024]
According to this diagnostic method, when a void discharge occurs in the winding portion of the rotating electric machine in response to applying an impulse voltage from the impulse voltage generator to the power supply terminal of the rotating electric machine through a test line, the void is generated. The high-frequency current flowing through the test line due to the discharge is captured by the high-frequency current sensor. The observation device can observe the waveform of the high-frequency current captured in this manner together with the waveform of the impulse voltage output from the voltage conversion device.The waveform of the high-frequency current near the zero-crossing phase of the impulse voltage waveform can be observed. By observing, the deterioration diagnosis of the rotating electric machine is performed. In the vicinity of the phase where the impulse voltage waveform crosses zero, the switching noise generated by the impulse voltage generator is in a converged state, so that the deterioration diagnosis of the rotating winding can be performed without being adversely affected by the switching noise.
[0025]
In this case, a high-pass filter having a frequency band of an oscillating current accompanying the application of the impulse voltage as an attenuation band may be interposed between the high-frequency current sensor and the observation device. is there.
According to this configuration, the oscillating current associated with the application of the impulse voltage is attenuated by the high-pass filter, so that the high-frequency current associated with the void discharge, that is, a level much smaller than the oscillating current associated with the application of the impulse voltage. The high-frequency current can be captured with high sensitivity, and the degree of deterioration of the rotating electrical machine can be accurately determined based on the captured high-frequency current.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows an electrical configuration of a rotating electrical machine deterioration diagnosis apparatus according to the present embodiment. In FIG. 1, a three-phase low-voltage rotating electrical machine 1 to be diagnosed is disconnected from a power supply line, and one end of a pair of test wires 2 is connected to two of the U-phase, V-phase, and W-phase power supply terminals. I do. A voltage output terminal of the impulse voltage generator 3 is connected to the other end of the test line 2 so that the output voltage of the impulse voltage generator 3 can be applied to the winding of the rotating electric machine 1. The impulse voltage generating device 3 is configured to output, for example, an impulse voltage having a maximum peak voltage of 3 kV, a wave front length of 1 to 2 μs, and a wave tail length of 50 μs.
[0027]
The current transformer 4 (corresponding to a high-frequency current sensor) is installed so as to be able to measure a high-frequency current flowing through the test line 2, and has a flat output characteristic in a frequency band of 2 kHz to 30 MHz, for example. . The secondary side output of the current transformer 4 is supplied to an A / D conversion module 6 through a high-pass filter 5. In this case, the pass frequency band of the high-pass filter 5 is set to a value sufficiently higher than the frequency band of the oscillating current accompanying the application of the impulse voltage from the impulse voltage generator 3, for example, 1 MHz or more.
[0028]
The voltage conversion device 7 is installed to reduce the impulse voltage applied to the test line 2 to a voltage level that can be input to the A / D conversion module 6, and the input voltage / output voltage ratio is 1 /. It is set to 1000. The output of the voltage converter 7 is used to detect the phase of the impulse voltage applied to the test line 2.
[0029]
The A / D conversion module 6 includes a buffer memory set to a capacity of at least about 64K words, and has a sampling frequency set to about 100 MHz, and a signal input from the current transformer 4 through the high-pass filter 5 and The signal input from the voltage conversion device 7 is converted into a digital signal, and is provided to a personal computer 8 (corresponding to an observation device). The personal computer 8 displays the output waveform of the current transformer 4 and the output waveform of the voltage converter 7 output through the high-pass filter 5 on the monitor based on the input digital signal. The personal computer 8 is configured to be able to execute the operation start and operation stop control of the impulse voltage generator 3 through the control line 9.
[0030]
Here, the rotary electric machine 1 is subjected to varnish treatment mainly for fixing the windings so as not to move due to electromagnetic vibration during operation. In general, a resin composed of a high-molecular organic material is used for this type of varnish. However, a varnish made of such a material is partially oxidized / heated by the heat of the rotating electric machine 1 during operation. It scatters with a reduced molecular weight, and the scattered portions become voids in the resin. When an electric field is applied to the dielectric around the void, a discharge is generated at a relatively low electric field (a so-called void discharge), which causes discharge deterioration.
[0031]
When an impulse voltage is applied to the winding of the rotating electric machine 1 in which such a void exists, a partial discharge may be generated in the void according to the voltage level. The strength of the electric field in the void (Eb) is:
Eb = 3E / (2 + 1 / εs)
It becomes. Here, E is the intensity of the applied electric field. In this case, since εs of a varnish made of a high-molecular-weight organic material is generally about 4, it is considered that discharge starts when an electric field that is about 1.3 times lower than usual is applied.
[0032]
Generally, when an impulse voltage is applied to a winding of a rotating electrical machine, the applied voltage attenuates and vibrates due to the inductance and the stray capacitance of the winding. At this time, if a void exists in the varnish around the winding, a void discharge occurs in that portion, and the voltage applied before the discharge changes to zero. An order of high-frequency current flows. Therefore, if the high-frequency current generated by the discharge is captured, the deterioration of the rotating electric machine can be diagnosed.
[0033]
In the present embodiment, the following measurement operation is performed to perform such deterioration diagnosis. That is, one end of the pair of test wires 2 is connected to two of the U-phase, V-phase, and W-phase power terminals of the rotating electrical machine 1 to be diagnosed, for example, the U-phase power terminal and the V-phase power terminal. The other end of the test line 2 is connected to the output terminal of the impulse voltage generator 3. In this connection state, the impulse voltage generator 3 outputs an impulse voltage (a maximum crest voltage value of 3 kV, a wave front length of 1 to 2 μsec, and a wave tail length of 50 μsec).
[0034]
In this case, the current transformer 4 is configured to have a flat output characteristic in a frequency band of 2 kHz to 30 MHz, so that the oscillating current (frequency is A signal including both components of, for example, about 50 kHz) and a high-frequency current (frequency is, for example, about 5 MHz) accompanying the void discharge is induced, and this signal is supplied to the A / D conversion module 6 via the high-pass filter 5. In this case, since the pass frequency band of the high-pass filter 5 is set to 1 MHz or more, the oscillating current due to the impulse current at a level much larger than the high-frequency current associated with the void discharge is attenuated, and the two currents can be reliably discriminated. The high-frequency current at a relatively low level accompanying the void discharge can be captured with high sensitivity. In this case, it is desirable that the S / N ratio between the high-frequency current and the impulse current be 5000 times or more.
[0035]
The signal output from the current transformer 4 through the high-pass filter 5, that is, the signal corresponding to the high-frequency current waveform associated with the void discharge is converted into a digital signal by the A / D conversion module 6 and transmitted to the personal computer 8. Given. Further, a signal output from the voltage conversion device 7, that is, a voltage signal obtained by reducing the impulse voltage to 1/1000 is also given to the personal computer 8 converted into a digital signal by the A / D conversion module 6. The personal computer 8 captures the input digital signals and displays a high-frequency current waveform and an impulse voltage waveform indicated by each signal on a monitor. Note that the current waveform and the voltage waveform displayed in this manner are those when an impulse voltage is applied to the U-phase power terminal and the V-phase power terminal of the rotary electric machine 1, but the V-phase power terminal and the W-phase power terminal By applying an impulse voltage to the W-phase power terminal and the U-phase power terminal, the high-frequency current waveform and the impulse voltage waveform can be similarly displayed on the monitor of the personal computer 8.
[0036]
FIG. 2 shows a waveform example when the above-described measurement operation is performed by the apparatus of the present embodiment with respect to the rotating electric machine 1 that has been deteriorated to a state in which void discharge can be generated in response to the application of the impulse voltage. In FIG. 2, a waveform denoted by reference numeral 10 indicates an impulse voltage waveform output from the voltage converter 7, and a waveform denoted by reference numeral 11 indicates a waveform of a high-frequency current output from the current transformer 4 through the high-pass filter 5. Is shown. In the case of this measurement example, it can be confirmed based on the high-frequency current waveform 11 that four discharges have occurred with respect to one impulse voltage application.
[0037]
Of the four discharges, A is the first discharge, B is the second discharge, C is the third discharge, and D is the fourth discharge. In a normal case, the first discharge A is likely to include switching noise at a timing T1 at which a built-in switching element (for example, a thyristor switch) of the impulse voltage generator 3 is turned on. It is difficult to determine the accompanying discharge. Further, the third discharge C coincides with the timing T3 at which the built-in switching element is cut off, which is indicated by the impulse voltage waveform 10, and switching noise may be included in this portion as well, which accompanies deterioration of the rotary electric machine 1. It is difficult to determine the discharge. Therefore, the most effective discharge when judging the deterioration of the winding of the rotating electric machine 1 based on the high-frequency current waveform 11 is to confirm the discharge B or the discharge D near the zero-cross timings T2 and T4 of the impulse voltage waveform 10. It is. The high-frequency current waveforms 11 at the timings T2 and T4 are likely to be void discharges in the varnish due to the deterioration of the rotating electric machine 1, and are effective as a deterioration diagnosis of the rotating electric machine 1. In the present embodiment, of the high-frequency current waveform 11 displayed on the personal computer 8 as a measured value, attention is paid to the high-frequency current waveform 11 near the first zero crossing of the impulse voltage waveform 10 displayed on the same screen as this. The peak value of the high-frequency current waveform 11 at that timing, the current continuation time, or the characteristic amount of the waveform captured by envelope processing of the waveform or the like is grasped, and the deterioration of the rotary electric machine 1 is determined by comparison with a preset deterioration reference value. Judge the degree. Note that such determination can be made by the operator observing the waveform displayed on the personal computer 8, but the calculation of the high-frequency current waveform 11 and the calculation position and A configuration may be adopted in which a comparison process with a set reference value is performed, whereby the degree of deterioration of the rotating electric machine 1 can be automatically determined.
[0038]
In short, according to the above-described embodiment, the impulse voltage is applied from the impulse voltage generator 3 through the test line 2 between any two of the U, V, and W phase power supply terminals of the rotating electric machine 1. When a void discharge occurs in the winding portion of the rotating electric machine 1, the high-frequency current flowing through the test line 2 due to the void discharge is captured by the current transformer 4, and the captured high-frequency current is transmitted by the personal computer 8. Observation determines the degree of deterioration of the rotating electric machine. In this case, since the change in the electrical characteristics due to the generation of voids due to thermal deterioration is measured, it can be applied to most rotating electric machines 1 irrespective of the type (fully closed type, open type, etc.). That is, the deterioration diagnosis of the windings of the rotating electric machine 1 can be accurately performed regardless of the type of the rotating electric machine 1.
[0039]
Further, the current transformer 4 captures not only the high-frequency current caused by the void discharge but also the component of the oscillating current generated when an impulse voltage is applied between the power supply terminals of the rotating electric machine 1. According to the configuration of the example, since the oscillating current accompanying the application of the impulse voltage is attenuated by the high-pass filter 5, the oscillating current associated with the void discharge, that is, the oscillating current associated with the application of the impulse voltage is much smaller. A high-frequency current of a level can be captured with high sensitivity, and the degree of deterioration of the windings of the rotating electrical machine 1 can be accurately determined based on the captured high-frequency current.
[0040]
Furthermore, when an impulse voltage is applied between the power supply terminals of the rotary electric machine 1 in a state where void discharge can occur in the winding portion, the impulse voltage oscillates, so that a plurality of void discharges are generated, and each void discharge is generated. The generated high-frequency current is captured by the current transformer 4, but the high-frequency current captured in this way has a high possibility that switching noise in the impulse voltage generator 3 is included. Therefore, it is necessary to exclude such a captured high-frequency current from the determination target of the degree of deterioration of the winding.
[0041]
In the present embodiment, the applied impulse voltage is stepped down by the voltage converter 7 and then A / D converted and applied to the personal computer 8, which captures the applied impulse voltage waveform by the current transformer 4. It is configured to output in a state that can be compared with the obtained high-frequency current waveform. Therefore, based on the comparison between the two waveforms, the high-frequency current waveform that may include switching noise in the impulse voltage generator 3 can be easily excluded from the determination target of the deterioration degree of the winding, As a result, the accuracy of determining the degree of deterioration of the winding is improved. In the case of comparing such waveforms, in the present embodiment, the components in the period in the vicinity of the phase where the impulse voltage waveform crosses zero, that is, in the period in which the switching noise generated in the impulse voltage generating device 3 is in a converged state. Since the degree of deterioration of the windings of the rotating electric machine 1 is determined based on this, the deterioration diagnosis can be performed without being adversely affected by the switching noise.
[0042]
It should be noted that the present invention is not limited to the above-described embodiment, and can be expanded or modified as described below.
When the impulse voltage generator 4 is configured to generate an impulse voltage during a period from when a built-in switching element (for example, a thyristor switch) is turned on to when it is turned off, the personal computer 8 is connected to the built-in switching element. Of the high-frequency current captured through the current transformer 4 as noise within a set time (for example, 0.5 μsec) from the ON and OFF times of the high-frequency current captured at other voltage phases. The configuration may be such that the degree of deterioration of the windings of the rotating electric machine 1 is determined based on the observation. According to this configuration, it is possible to eliminate the adverse effect due to the switching noise in the impulse voltage generating device 3, and the accuracy of determining the degree of deterioration of the winding is improved.
[0043]
The personal computer 8 extracts a component near the phase where the impulse voltage waveform crosses zero from the high-frequency current components captured through the current transformer 4, and based on a comparison between the extracted high-frequency current component and a previously stored reference value, the rotating electric machine The configuration may be such that the degree of deterioration of one winding is automatically determined. According to this configuration, of the high-frequency current components captured through the current transformer 4, during a period near the phase where the impulse voltage waveform crosses zero, that is, during a period when the switching noise generated by the impulse voltage generator 3 is converged. Since the degree of deterioration of the windings of the rotating electric machine 1 is automatically determined based on the components, the deterioration diagnosis can be performed without being adversely affected by the switching noise.
[0044]
【The invention's effect】
As described above, according to the present invention, the deterioration diagnosis of the windings of the rotating electric machine can be accurately performed by a method irrespective of the surrounding environment of capturing the void discharge phenomenon due to the impulse voltage application and independent of the type of the rotating electric machine. What can be done.
[Brief description of the drawings]
FIG. 1 is an electrical configuration diagram showing one embodiment of the present invention. FIG. 2 is a diagram showing a measurement example of a high-frequency current waveform and an impulse voltage waveform.
1 is a rotating electric machine, 2 is a test line, 3 is an impulse voltage generator, 4 is a current transformer (high-frequency current sensor), 5 is a high-pass filter, 6 is an A / D conversion module, 7 is a voltage converter, and 8 is a personal computer. (Observation device), 9 is a control line, 10 is an impulse voltage waveform, and 11 is a high-frequency current waveform.

Claims (7)

An impulse voltage generator for applying an impulse voltage through a test line between power supply terminals of a rotating electrical machine to be deteriorated, and
A high-frequency current sensor provided so as to capture a high-frequency current flowing through the test line,
An observation device capable of observing the high-frequency current captured by the high-frequency current sensor,
By applying an impulse voltage from the impulse voltage generator between the power supply terminals of the rotating electric machine and observing the high-frequency current captured by the high-frequency current sensor with the observation device at this time, the deterioration of the windings of the rotating electric machine is improved. An apparatus for diagnosing deterioration of a rotating electric machine, wherein the degree is determined. The deterioration diagnosis device for a rotating electric machine according to claim 1, wherein a high-pass filter having a frequency band of an oscillating current accompanying the application of the impulse voltage as an attenuation region is interposed between the high-frequency current sensor and the observation device. A voltage conversion device that reduces the impulse voltage applied to the test line from the impulse voltage generator and provides the voltage to the observation device,
3. The rotating electric machine according to claim 1, wherein the observation device outputs an impulse voltage waveform provided from the voltage conversion device in a state that can be compared with a high-frequency current waveform captured by the high-frequency current sensor. 4. Degradation diagnosis device. The observation device extracts, from the high-frequency current components captured through the high-frequency current sensor, components near the phase where the impulse voltage waveform crosses zero, and based on the extracted high-frequency current components, deteriorates the windings of the rotating electric machine. The apparatus for diagnosing deterioration of a rotating electric machine according to claim 3, wherein the degree is determined. The impulse voltage generator is configured to generate the impulse voltage during a period from when the built-in switching element is turned on to when it is turned off,
The observation device has a determination function of removing high-frequency current captured through the high-frequency current sensor as noise within a set time from each time of turning on and off the built-in switching element, and a high-frequency current captured at other voltage phases. The deterioration diagnosis device for a rotating electric machine according to any one of claims 1 to 3, wherein a degree of deterioration of a winding of the rotating electric machine is determined based on an observation of a current. An impulse voltage generator for applying an impulse voltage through a test line between power supply terminals of a rotating electrical machine to be deteriorated, and
A high-frequency current sensor provided so as to capture a high-frequency current flowing through the test line,
A voltage converter that reduces the impulse voltage applied to the test line from the impulse voltage generator and gives the voltage to the observation device;
An observation device capable of observing a waveform of a high-frequency current captured by the high-frequency current sensor and a waveform of an impulse voltage from the voltage conversion device,
A method for diagnosing deterioration of the rotating electric machine, wherein the deterioration diagnosis of the rotating electric machine is performed by observing a waveform of the high-frequency current near a phase where the impulse voltage waveform observed by the observation device crosses zero. 7. The method for diagnosing deterioration of a rotating electrical machine according to claim 6, wherein a high-pass filter having a frequency band of an oscillating current accompanying the application of the impulse voltage as an attenuation region is interposed between the high-frequency current sensor and the observation device.

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