JP5627186B2 - Anomaly monitoring device for electrical equipment and anomaly monitoring device for accelerator device - Google Patents

Description

  The present invention relates to an abnormality monitoring device for an electrical apparatus and an abnormality monitoring device for an accelerator device that detect an abnormality by detecting an electromagnetic wave caused by a partial discharge generated by an insulation abnormality in a high voltage generation unit or a high voltage application unit.

A medical accelerator device will be described as an example of an electrical device. Medical accelerator devices in which high-energy electromagnetic radiation or particle beam radiation is generated are used in radiation therapy medicine. With this device, the patient's body area is irradiated with radiation and used for treatment. Radiation therapy is given to block the ability of tumor cells to divide or kill these cells, particularly in cancer therapy. A medical accelerator device is an incident system that pre-accelerates an ion beam (ion source), a synchrotron (acceleration system) that accelerates the beam to an energy suitable for treatment by entering the beam from the incident system, and emitting the accelerated beam (outgoing) System) and a high-energy beam transport system that efficiently leads to the designated irradiation chamber, an irradiation system that properly irradiates the tumor with the supplied beam, and adjustment of the medical accelerator device,
It consists of a control system that supervises operation management, status monitoring, etc. In addition, each system is supplied with electric power from several hundred power sources.

As a conventional function monitoring method in such a medical accelerator device, a signal that qualitatively characterizes the operation of the medical accelerator device is automatically detected and digitized, and the subsequent signal is digitized. The data is stored in a data processing device to be provided for evaluation within the framework of a computer-aided medical accelerator device function test (for example, Patent Document 1).
In another conventional example, arc discharge in a power cable is detected in a timely manner by a microwave horn antenna that responds to 1 MHz to 3 GHz, and power supply from the power panel to the power cable in which arc discharge has occurred can be cut off. An arc discharge detection method that can be performed is disclosed (for example, Patent Document 2).
In addition, as a method for diagnosing device insulation in another conventional example, a method of detecting a partial discharge generated in a stator winding with a patch antenna is disclosed (for example, Patent Document 3).

Japanese Patent Laying-Open No. 2006-324249 (page 4, lines 24 to 28, FIG. 1 and page 11, lines 14 to 24, FIG. 2) JP-A-7-198768 (page 3, left column, lines 3 to 14, line 1) Japanese Patent Laying-Open No. 2006-250772 (page 4, lines 11 to 18, FIG. 1 and page 4, line 50 to page 5, line 4, FIG. 3)

  A medical accelerator device is a large, expensive, and highly advanced medical treatment device. The biggest problem with this device is that when the function of the device stops, it becomes impossible to treat a large number of patients, which has a great social impact. As a cause of the malfunction of the equipment, there are a case where the equipment deviates from the normal operating range during operation and an insulation deterioration of a high voltage portion in a range where the equipment is operating normally. In Patent Document 1, although the function can be monitored when the device deviates from the normal operating range, it is not possible to monitor the partial discharge that is a precursor of the insulation deterioration of the high voltage portion.

As a method for detecting arc discharge of a power cable of a power supply panel in which a large number of devices are arranged, there is a technique of Patent Document 2, but the microwave horn antenna of Patent Document 2 has a wide detection frequency band of 1 MHz to 3 GHz. Even if the discharge can be detected, it is difficult to distinguish the partial discharge from the ambient noise, and the partial discharge cannot be detected in practice.
In Patent Document 3, a partial discharge is detected by installing a patch antenna in a metal container frame of an electric motor, but in an apparatus that is an open space such as a medical accelerator device and includes a large number of devices. When detecting partial discharge at multiple locations outside the metal container of each device, it detects noise that occurs outside the monitored area and electromagnetic waves caused by discharge that occurs outside the monitored area, so There was a problem that it was difficult to distinguish from discharge.

  The present invention has been made to solve the above-described problems, and an abnormality monitoring apparatus and an accelerator for an electric device that can control the directivity of an antenna to monitor a plurality of monitoring target portions and detect the occurrence of an abnormality. The object is to obtain a device abnormality monitoring device.

An abnormality monitoring apparatus for electrical equipment according to the present invention includes an array antenna having a plurality of patch antennas for detecting electromagnetic waves associated with partial discharges caused by an insulation abnormality in a plurality of high voltage generation sections or high voltage application sections of the electrical equipment, and A phase converter connected to the patch antenna for shifting the phase of the output of the patch antenna; a plurality of amplitude converters respectively connected to the plurality of patch antennas; and a plurality of phase shift amounts of the phase converter The high voltage generation unit or the high voltage application unit is controlled according to the direction from each of the plurality of patch antennas, and the amplitudes of the plurality of amplitude converters are controlled according to the directions of electromagnetic waves received by the plurality of patch antennas. a controller for controlling Te, includes an output of the patch antenna phase shift amount is controlled, said plurality of Patchian whose amplitude is controlled And a combiner for combining the outputs of Na, to have a directivity by controlling the amplitude of the plurality of amplitude converter according to the specific direction of the electromagnetic wave by the plurality of patch antenna receives a specific direction of the electromagnetic wave , in which to detect the respective insulation abnormality of the plurality of high voltage generating unit based on the output of the combiner or high voltage application unit.

According to the abnormality monitoring apparatus for electrical equipment of the present invention, a phase converter that is connected to a patch antenna and shifts the phase of the output of the patch antenna, a plurality of amplitude converters that are respectively connected to a plurality of patch antennas, The phase shift amount of the phase converter is controlled according to the direction from each of the plurality of patch antennas of each of the plurality of high voltage generation units or high voltage application units, and the amplitudes of the plurality of amplitude converters are A controller that controls the direction of the electromagnetic wave received by the patch antenna; and a synthesizer that combines outputs of the plurality of patch antennas whose amplitudes are controlled, including outputs of the patch antennas whose phase shift amount is controlled. And controlling the amplitude of the plurality of amplitude converters according to a specific direction of the electromagnetic wave received by the plurality of patch antennas, thereby providing directivity in the specific direction of the electromagnetic wave. Myself understood, and detects the combiner outputs of said plurality of high voltage generator or high voltage applying unit based on the respective insulating abnormal, without changing the orientation of the antenna mechanically, to control the directivity of the antenna It is possible to detect an abnormality by monitoring a plurality of monitored parts. By appropriately setting and controlling the phase shift amount of the phase converter and the amplitude conversion amount of the amplitude converter, not only the direction of high gain but also the direction of low gain can be variably controlled. Can easily achieve a high gain and a low gain in the direction of the noise source.
Moreover, the electrical equipment of the present invention is an accelerator device, and the present invention is suitable for an abnormality monitoring device for an accelerator device.

It is a block diagram which shows the abnormality monitoring apparatus of the accelerator apparatus in basic technology. It is a disassembled perspective view which shows the patch array antenna in the abnormality monitoring apparatus of the accelerator apparatus of basic technology. It is sectional drawing of the patch array antenna shown in FIG. It is sectional drawing seen from the AA line of FIG. 3 in the arrow direction. It is a monitoring flowchart which monitors the partial discharge in the abnormality monitoring apparatus of the accelerator apparatus of basic technology. It is a block diagram which shows the abnormality monitoring apparatus of the accelerator apparatus in other basic technology. It is a block diagram which shows the abnormality monitoring apparatus of the electric equipment in Embodiment 1 of this invention. 6 is a diagram illustrating a basic operation according to an incident direction of an electromagnetic wave to each excitation patch in the first embodiment. FIG. 6 is a diagram illustrating an operation when the electromagnetic wave generation source in Embodiment 1 is at a short distance. FIG. 6 is a diagram showing a two-dimensional map A and a two-dimensional scan map B in Embodiment 2. FIG. FIG. 6 is a diagram showing a two-dimensional map C in the second embodiment.

Basic Technology FIG. 1 is a configuration diagram showing an abnormality monitoring device for an accelerator device in the basic technology. FIG. 2 is an exploded perspective view showing a patch array antenna in the abnormality monitoring device for the accelerator device of the basic technology. 3 is a cross-sectional view of the patch array antenna shown in FIG. 4 is a cross-sectional view taken along the line AA in FIG. FIG. 5 is a monitoring flowchart for monitoring the partial discharge in the abnormality monitoring device of the accelerator device of the basic technology. Hereinafter, a description will be given based on the drawings.

  A medical accelerator device will be described as an example of an electrical device. The medical accelerator apparatus 1 includes an accelerator system 12, and a power source (A) 13, a power source (B) 14, a power source (C) 15, a power source (D) installed around the accelerator system 12 to operate the accelerator system 12. ) 16, a power source (E) 17, and a high voltage cable 18 and a power cable 19 that supply power from each of these power sources, and the accelerator system 12 is supplied with power for various operations. Yes. In particular, the accelerator system 12 needs to be operated at a high voltage, and the power source (A) 13 in FIG. 1 is a power source that generates a DC high voltage pulse of 70 kV, and the DC high voltage pulse is transmitted through the high voltage cable 18 to the accelerator system. 12 is supplied. The DC high voltage pulse, for example, continuously generates a rectangular wave with a high voltage generation time of 30 μsec at 100 msec intervals, and the generation time and generation interval vary depending on the operating state.

  The abnormality monitoring device 2 of the medical accelerator apparatus 1 receives signals from the electromagnetic wave detection means 23 and the high voltage signal detection means 26 installed in the vicinity of the power source (A) 13, and the electromagnetic wave detection means 23 and the high voltage signal monitor 28. The signal processing means 24 for performing signal processing and the monitoring means 25 are configured. The electromagnetic wave detection means 23 includes a patch array antenna 20, a high-frequency coaxial cable 21, and an electromagnetic wave detector 22. The electromagnetic wave detection means 23 receives an electromagnetic wave accompanying a partial discharge caused by an insulation abnormality using the patch array antenna 20, and receives the received signal as a high frequency signal. The signal is transmitted to the electromagnetic wave detector 22 through the coaxial cable 21.

  The patch array antenna 20 is configured as shown in FIGS. 2, 3 and 4 in order to achieve high directivity. The configuration of the patch array antenna 20 will be described with reference to FIGS. The patch array antenna 20 includes a dielectric substrate 31, a reinforcing plate 38, a non-excited patch 36, and a dielectric 37. The dielectric substrate 31 is provided with four excitation patches 32, a feeding point 34, and a feeding microstrip line 33 on the front surface. The feed line from the feed point 34 is a feed microstrip line 33 in order to reduce unnecessary radiation, and the lengths from the feed point 34 to each excitation patch 32 of the feed microstrip line 33 are all equal. The power supply microstrip line 33 is formed on the same substrate as the excitation patch 32, and the length from the power supply point 34 to each excitation patch 32 is the same, thereby reducing the level of unnecessary radiation from the power supply microstrip line. As a result, the reception characteristics of the antenna are improved, the directivity can be increased, and detection can be performed with high sensitivity. The shape dimension of the excitation patch 32 is determined by the design specifications of the center frequency and bandwidth of the patch array antenna 20. The entire back surface of the dielectric substrate 31 is a ground electrode 35. By configuring with a patch array antenna, it is possible to detect high frequencies in the GHz band with high sensitivity in a narrow band.

  FIG. 3 is a cross-sectional view showing a three-dimensional structure of the patch array antenna 20. As shown in FIG. 3, the excitation patch 32 on the front surface of the dielectric substrate 31 having a laminated structure, the microstrip line 33 for power feeding (not shown), and the ground electrode 35 on the back surface are in close contact with the dielectric substrate 31. And the ground electrode 35 sandwich the dielectric substrate 31. The front and back surfaces of the copper-clad dielectric substrate 31 are etched by chemical processing to form a pattern. The non-excitation patch 36 is made of aluminum and has an outer dimension that is larger than the excitation patch 32 in both the vertical and horizontal directions, and is bonded to the dielectric (B) 37 at a position shown in FIG. It is fixed. A high directivity is realized by arranging a non-excited patch 36 disposed opposite to the excited patch 32 via a gap and covering the excited patch 32 and the non-excited patch 36 with a ferroelectric substance.

  The shape of the dielectric (B) 37 is a concave box shape as shown in FIG. 2, and the dielectric (B) 37 is made of aluminum provided on the back surface of the dielectric substrate 31 so as to face the dielectric substrate 31. The set screw 42 together with the reinforcing plate 38 is inserted into the set hole 40 and the screw hole 41 and fixed integrally. A hatched portion of the dielectric (B) 37 in FIG. 2 shows a cross section of the dielectric (B) 37. The joint surface between the dielectric substrate 31 and the dielectric (B) 37 is fixed via a sealant. Atmospheric pressure air exists in the gap 39 surrounded by the dielectric substrate 31 and the dielectric (B) 37, the spatial distance between the excitation patch 32 and the non-excitation patch 36, and the relative dielectric constant of the dielectric (B) 37. Is designed at the point where the directivity of the patch array antenna 20 is the best.

  With this configuration, the electric power supplied to the feeding point 34 passes through the feeding microstrip line 33 to excite the excitation patch 32, and radio waves are radiated from the excitation patch 32. The radiated radio wave excites a parasitic non-excited patch 36 by electromagnetic coupling, and the radio wave is radiated from the non-excited patch 36 to function as an antenna. Further, the excitation frequency band is broadened by making the shape of the non-excitation patch 36 larger (giving a difference) than the excitation patch 32, and the directivity can be improved by sharing two frequencies with the excitation frequency of the excitation patch 32. Sensitivity can be detected. Although it is possible to widen the excitation frequency band by increasing the thickness of the dielectric substrate 31, unnecessary radiation increases and directivity deteriorates.

The dielectric substrate 31 of the basic technology is a glass Teflon (registered trademark) laminate, for example, has a relative dielectric constant of 2.6, a thickness of 0.8 mm, an excitation patch 32 of 51 × 51 mm, and a thickness of 50 to 100 μm.
The non-excitation patch 36 is 62 × 110 mm, the thickness is 1.5 mm, the spatial distance between the excitation patch 32 and the non-excitation patch 36 is 6 mm, and the dielectric (B) 37 is a polycarbonate having a relative dielectric constant of 2.7. By configuring as described above, the small and highly directional patch array antenna 20 having the characteristics of VSWR (Voltage Standing Wave Ratio) = 1.33 or less with a bandwidth of 2.5% with respect to the center frequency can be obtained. Can be obtained.

  The patch array antenna 20 configured as described above is placed close to the high voltage generating portion of the power source (A) 13 and the connection insulating portion with the high voltage cable 18. In the basic technology, the antenna characteristic is used to receive an electromagnetic wave accompanying a partial discharge caused by an insulation abnormality. As described above, the power source (A) 13 of FIG. 1 generates a DC high voltage pulse of 70 kV. The generation of this DC high voltage pulse is detected by the high voltage signal detection means 26, monitored by the high voltage signal monitor 28, and transmitted to the signal processing means 24.

  Next, the operation will be described. When the medical accelerator device is operated, the power source (A) 13 generates a high voltage pulse, and the high voltage pulse is supplied to the accelerator system 12 via the high voltage cable 18. When operated for a long time in this state, there may be a case where a partial discharge, which is a precursor of dielectric breakdown, may occur due to insulation deterioration at the high voltage generating portion of the power source (A) 13 or the insulating portion of the high voltage cable. An electromagnetic wave in a high frequency band accompanying the occurrence of the partial discharge is detected by a highly directional patch array antenna 20 installed in the vicinity of the power source (A) 13 to detect an abnormality in the power source (A) 13. When this abnormality occurs, noise similar to partial discharge often occurs from the power source (B) 14, the power source (C) 15, the power source (D) 16, and the power source (E) 17. Therefore, the electromagnetic wave of only the power source (A) 13 is detected by detecting the electromagnetic wave by installing a highly directional patch array antenna 20 facing a portion where the insulation degradation of the power source (A) 13 may occur, that is, facing it. Can be detected.

  However, the generation of electromagnetic waves accompanying the generation of the high voltage pulse of the power source (A) 13 cannot be ignored, resulting in noise for the measurement of the patch array antenna 20. Therefore, it is necessary to suppress only noise of the power source (A) 13 and detect only the electromagnetic waves accompanying the partial discharge. As a noise suppression method, the basic technology uses a frequency band limiting method. A band with low noise is selected from the frequency characteristics of noise due to the high-frequency pulse measured in advance, and is set as a detection band. In the patch array antenna 20, the detection band is set as a center frequency.

A monitoring flowchart is shown in FIG. As described above, the signal detected by the electromagnetic wave detecting means 23 is transmitted to the signal processing means 24, detected by the high voltage signal detecting means 26 (step S1), and synchronized with the signal monitored by the high voltage signal monitor 28. Measurement is performed (step S2), and the measured value is transmitted to the monitoring means 25. The monitoring means 25 compares with a prescribed value registered in advance (step S3), and if it exceeds the prescribed value, it determines that it is abnormal and issues an alarm (step S4). By doing so, the abnormality of the power source (A) 13 can be reliably detected.
As another method for suppressing noise of the power source (A) 13, there is a method of controlling the measurement time based on the signal monitored by the high voltage signal monitor 28. The occurrence of partial discharge in the case of the DC high voltage pulse described above is the rise and fall of the pulse. Therefore, the S / N ratio can be improved by measuring only when this pulse is generated, that is, by measuring the measurement time in synchronization with the signal monitored by the high voltage signal monitor 28, and the like. There is an effect.

FIG. 6 is a block diagram showing an abnormality monitoring device for an accelerator device according to another basic technology. In the figure, a medical accelerator device 50 includes an ion source 51, an incident system 52, an acceleration system 53, an emission system 54, a beam transport system 55, and an irradiation system 56 that serve as a high voltage generation unit or a high voltage application unit. . The medical accelerator device 50 includes a patch array antenna 20a to 20g, electromagnetic wave detectors 22a to 22g, and an ion source 51, an incident system 52, an acceleration system 53, an emission system 54, a beam transport system 55, and an irradiation system 56, respectively. Motion signal detection means (high voltage signal detection means) 57a to 57g. The patch array antennas 20a to 20g are installed close to each other where a partial discharge may occur due to insulation deterioration such as a high voltage generation unit, a high voltage insulation unit, and a high voltage cable connection unit.

  A device having a plurality of high voltage parts such as an ion source 51 includes a plurality of patch array antennas 20 and an electromagnetic wave detector 22. Each of the electromagnetic wave detectors 22a to 22g and the operation signal detection means 57a to 57g has an Ethernet (registered trademark) output. Signals from the respective electromagnetic wave detectors 22a to 22g are connected to the signal processing means 59 via the network 58 via the HUB (A) 62a. The signals from the respective operation signal detection means 57a to 57g are connected to the signal processing means 59 via the network 61 through the HUB (B) 62b.

In the signal processing means 59, operation signal detection means 57 a to 57 g for each of the ion source 51, the incident system 52, the acceleration system 53, the extraction system 54, the beam transport system 55, and the irradiation system 56 according to the program set in the monitoring terminal 60. The signal processing is performed in synchronization with the above signal, and the result is transmitted to the monitoring terminal 60. When the electromagnetic wave accompanying the partial discharge is detected in synchronization with the operation signal of the monitoring target device, the discrimination accuracy between the noise and the discharge signal is improved. In the monitoring terminal 60, the signal value of each monitored device is recorded to display a temporal change, and the transmitted monitoring signal of each device is compared with a pre-registered prescribed value for each device, When the specified value is exceeded, it is determined as abnormal and an alarm is issued for each device.
In this way, each patch array antenna is installed facing each part of the monitored device that is the high voltage generating unit or the high voltage applying unit, and the electromagnetic waves accompanying the partial discharge generated due to the insulation abnormality of each part of the monitored device, By detecting each with a patch array antenna in synchronization with the operation signal of the device to be monitored, it is possible to specify the discharge generation unit.

  Next, the operation will be described. The operation signal detection means 57a-57g provided in the ion source 51, the incident system 52, the acceleration system 53, the emission system 54, the beam transport system 55, and the irradiation system 56 are operated signals (high voltage signals) corresponding to the respective devices. ) Is detected. For example, the ion source 51 generates each ion to be used for treatment, and the incident system 52 performs preliminary acceleration for entering the synchrotron. The ion source has a high intensity, and it is necessary to remove electrons as much as possible in order to increase the acceleration efficiency to generate multiply charged ions. A high voltage / high magnetic field generator for making an ion source using high energy electrons. Is used.

The beam emitted from the ion source is converged, accelerated, transported to a linear accelerator that performs preliminary acceleration until it enters the synchrotron, and is accelerated to several MeV. Further, it is incident on a synchrotron as a main accelerator, accelerated to several hundred MeV, and taken out. High magnetic field and high voltage devices are often used for such convergence and acceleration. Hereinafter, the emission system 54 and the beam transport system 5
5. For the irradiation system 56, high power and high voltage devices are often used. The operation signal detectors 57a to 57g provided in these devices detect the operation signals corresponding to these devices. The patch array antennas 20a to 20g are designed to have a detection frequency that is an optimum S / N ratio of each device. If a partial discharge due to an insulation abnormality occurs in any of the ion source 51, the incident system 52, the acceleration system 53, the emission system 54, the beam transport system 55, and the irradiation system 56, an abnormality is detected. By comprising in this way, the insulation abnormality of each part of the medical accelerator apparatus which is large-scale can be monitored. The failure of the medical accelerator device can be predicted by monitoring the partial discharge.

Embodiment 1 FIG.
FIG. 7 is a configuration diagram showing the abnormality monitoring apparatus for electrical equipment in the first embodiment. The patch array antenna used in the first embodiment is the patch array antenna 20 described in detail with reference to FIGS. 2, 3, and 4 and is configured in the same manner, and is an array antenna having a plurality of patch antennas. In FIG. 7, the excitation patches 32a, 32b, 32c, 32d of the patch array antenna are
The phase converters 63a, 63b, 63c, and 63d and the amplitude converters 66a, 66b, 66c, and 66d are connected to the combiner 65, and the output is input to the electromagnetic wave detector 22. Phase conversion amount and amplitude converters 66a, 66b in the phase converters 63a, 63b, 63c, 63d,
The amplitude conversion amounts 66 c and 66 d are controlled by the controller 64.

Next, the operation of the abnormality monitoring apparatus for an electrical device having such a configuration will be described. The electromagnetic waves that reach the excitation patches 32a, 32b, 32c, and 32d of the patch array antenna are shifted in phase or delayed in time by the respective phase converters 63a, 63b, 63c, and 63d, and then synthesized by the synthesizer 65. Is done. Therefore, when electromagnetic waves are incident from the front and are simultaneously detected by the respective excitation patches, the combined output is maximized when the phase conversion amount of the phase converter is the same value. At this time, the amplitude conversion amounts of the amplitude converters 66a, 66b, 66c, and 66d adjust the gain (weighting). On the other hand, when electromagnetic waves are incident from an oblique direction instead of the front, there is a difference in the arrival time to each excitation patch. Therefore, if the phase of the incident electromagnetic waves is shifted to compensate for this difference, the combined output increases. Otherwise, they cancel each other out and the combined output becomes low.

FIG. 8 is a diagram showing a basic operation according to the incident direction of the electromagnetic wave to each excitation patch. FIG. 8 shows the phase and incident angle of an input electromagnetic wave when two patch antennas constituting the patch array antenna are arranged for convenience of explanation. The distance between the centers of the two excitation patches 32a and 32b is d (m). FIG. 8A shows a state in which electromagnetic waves are incident from the front of the patch array antenna. When an electromagnetic wave is incident at an angle of 0 degree with respect to the front surface, that is, the normal of the patch array antenna surface, the time when the electromagnetic wave reaches the excitation patches 32a and 32b is the same. That is, the time difference Δt = 0 (s) and the phase difference Δθ = 0 (rad). In this case, the combined output is doubled at maximum.

On the other hand, FIG. 8B shows a state in which electromagnetic waves are incident from the excitation patch 32b at an angle φ degree. At this time, the electromagnetic wave first reaches the excitation patch 32b, and reaches the excitation patch 32a after time Δt (s). If the frequency of the electromagnetic wave is f (Hz) and the speed of light is c (m / s), the time difference Δt and the phase difference Δθ are expressed by the following equations, respectively. Δt = d (sin φ) / c
Δθ = 2πf d (sin φ) / c
Therefore, by delaying the signal of the excitation patch 32b that has arrived first by Δt by the phase converter 63b, or in other words, by delaying the phase by Δθ, the phase of each electromagnetic wave signal enters the combiner 65. The maximum combined output is obtained.

  In this case, the phase of the signal of the excitation patch 32b may be delayed by Δθ by the phase converter 63b. Therefore, the connection of the other phase converter 63a is not necessarily required, and the signal of the excitation patch 32a is directly connected to the combiner 65. Add to That is, the synthesizer 65 synthesizes the signal of the excitation patch 32b delayed in phase by Δθ by the phase converter 63b and the signal of the excitation patch 32a, thereby obtaining the maximum combined output.

In the above description, the incident angle of the electromagnetic wave to the two patch antennas 32a and 32b is the same, that is, the electromagnetic wave generation source is sufficiently far from the distance between the patch antennas. On the other hand, when the electromagnetic wave generation source is at a short distance, the incident angles of the electromagnetic waves on the two patch antennas are different. In this case, for example, as shown in FIG. 9, the distance difference l = Δt · c from the electromagnetic wave generation source to each of the patch antennas 32a and 32b is a constant value, that is, the position of the patch antennas 32a and 32b. An electromagnetic wave generation source is located on a hyperbola 67 having a focal point of. Accordingly, by delaying the signal of the excitation patch 32a by Δt by the phase converter 63a (relative to the phase converter 63b), the phases coincide with each other when the respective electromagnetic wave signals enter the combiner 65, and the maximum combined output is obtained. can get. In the case of a short distance, the electromagnetic wave generation source can be expressed as a hyperbola by the time difference (phase difference).

In this case, since the signal of the excitation patch 32a may be delayed by Δt by the phase converter 63a, the connection of the other phase converter 63b is not necessarily required, and the signal of the excitation patch 32b is directly applied to the synthesizer 65. That's fine. That is, the combiner 65 combines the signal of the excitation patch 32a delayed by Δt by the phase converter 63a and the signal of the excitation patch 32b, thereby obtaining the maximum combined output.

  According to the basic principle based on the basic operation described above, in the patch array antenna, by appropriately controlling the phase shift amount of the phase converter, a plurality of monitoring target parts can be obtained without mechanically changing the direction of the patch array antenna. It is possible to monitor the occurrence of partial discharge sequentially by sequentially increasing the gains in the respective directions. That is, the output of the synthesizer 65 obtained by controlling the phase shift amount of the phase converter by the controller 64 according to the direction from each of the plurality of patch antennas of the plurality of high voltage generation units or high voltage application units. Based on this, it is possible to detect an insulation abnormality in each of the plurality of high voltage generation units or high voltage application units. This can reduce the number and space of the patch array antennas 20 compared to the case where the patch array antennas 20 are arranged for each system in FIG.

  Also, by appropriately setting and controlling the number and arrangement of patch antennas, the phase shift amount of the phase converter, and the amplitude conversion amount of the amplitude converter, it is possible to variably control not only the high gain direction but also the low gain direction. Since there are various noise sources, for example, it is easy to achieve a high gain in the direction of the monitoring target region and a low gain in the direction of the noise source with respect to the medical accelerator device. It is possible to realize an electrical equipment abnormality monitoring apparatus with a high / N ratio and high reliability. That is, in the direction of the noise source specified by setting and controlling the phase shift amount, the gain (weighting) can be lowered by setting and controlling the amplitude of the amplitude converter to be low, and the signal from the noise source can be lowered. it can. For this reason, the antenna directivity is sequentially set toward a plurality of monitoring target parts, and the antenna gain is decreased with respect to the direction of the noise generation source, thereby avoiding the direction of the noise generation source and the plurality of monitoring targets. The partial discharge of the part can be detected with high sensitivity.

  Furthermore, when the monitoring target part is relatively close to the distance between the patch antennas, the monitoring target part can be expressed by a hyperbola or a hyperboloid with the positions of the two patch antennas as the focal points. If it is used, two or more hyperbolas or hyperboloids can be obtained, so that the monitored part can be expressed not as a direction but as a position (that is, the intersection of both hyperbolas or both hyperbolases) itself, so that the S / N ratio is higher. An abnormality monitoring device can be realized. Note that three or more patch antennas can be realized by one or a plurality of patch array antennas.

The patch array antenna used in the first embodiment is the patch array antenna 20 described in detail with reference to FIGS. 2, 3, and 4, and is configured in the same manner. Therefore, the shape of the non-excitation patch 36 is the excitation patch 32. The excitation frequency band is widened by making it larger (giving a difference), and the directivity can be improved by sharing two frequencies with the excitation frequency of the excitation patch 32, so that detection can be performed with high sensitivity.
Furthermore, the electromagnetic wave accompanying the partial discharge generated by the insulation abnormality in the high voltage generation unit or the high voltage application unit is synchronized with the operation signal detected by the operation signal detection means (high voltage signal detection means). If the abnormality is detected by detecting with the patch array antenna, the discharge generating portion can be specified with higher sensitivity.

Embodiment 2
Here, setting control of the phase shift amount of the phase converter and the amplitude conversion amount of the amplitude converter when the abnormality monitoring device of the electrical apparatus is applied to the abnormality monitoring device of the medical accelerator apparatus will be described. The medical accelerator device is rarely changed during operation because the device arrangement is determined at the time of installation. Therefore, at the time of installation of the abnormality monitoring device of the medical accelerator device, the phase shift amount of the phase converter and the amplitude conversion amount of the amplitude converter are changed to give the directivity of the patch array antenna in a plurality of predetermined directions as a whole. . The determination of a plurality of predetermined directions and the identification of abnormal sites are performed according to the following procedure.

First step: Referring to FIG. 10A showing a two-dimensional map A, from the patch array antenna installation position (dielectric substrate 31) to the medical accelerator device (ion source 51, incident system 52, beam transport system 55, A two-dimensional map A in a range overlooking the noise generation source 71) is created, and the incident angle on the receiving surface of the patch antenna is specified using the monitoring target part and the noise generation source as the electromagnetic wave source. Φ ₁ , φ ₂ , φ ₃ , and φ ₄ are specified by the incident angles with respect to the normal of the receiving surface of the patch antenna.
At this time, the directional location where the occurrence of the insulation abnormality is assumed at the time of designing the medical accelerator device is also identified as the monitoring target region. Locations that excite electromagnetic waves similar to the monitoring frequency during normal operation when designing a medical accelerator device are not monitored.

Second step: The incident angles to the plurality of patch antennas (dielectric substrate 31) in the electromagnetic waves from the monitoring target parts (ion source 51, incident system 52, beam transport system 55, noise generation source 71) are set to be the same (parallel). , Scanning in a two-dimensional direction within a range where the medical accelerator device can be looked down from the patch antenna installation position (that is, scanning by controlling the phase shift amount with a phase converter), and the directional part where the gain becomes the maximum value when insulation is abnormal (Direction direction) is specified, and a two-dimensional scan map B (FIG. 10B) is created and recorded.

  Third step: At a plurality of directivity points where the gain of the two-dimensional scan map B shows a maximum value when insulation is abnormal, the gain is determined in consideration of the phase shift amount of each patch antenna and the incident angle with the monitored device as a discharge source. Adjust each to maximize. That is, the phase shift amount of the phase converter is adjusted so that the hyperbola 67 shown in FIG. 9 is scanned at each incident angle φ of the two-dimensional scan map B. Here, the pointing location where the maximum value is obtained is specified as the monitoring target portion or the monitoring target. From the two-dimensional scan map B and the two-dimensional map A showing the placement of the medical accelerator device overlooked, the phase shift amount of the two-dimensional phase converter directed to the noise generation source is determined, and the noise generation location is specified and monitored. Not applicable.

Fourth step: A monitoring two-dimensional map C shown in FIG. 11 is formulated based on the third step. At this time, the phase shift amount of the phase converter and the amplitude conversion amount of the amplitude converter are set and controlled so that the gain is maximized at the monitoring target directing portion and the gain is minimized at the non-monitoring directing portion. Measurement conditions.
Fifth step: Based on the monitoring two-dimensional map C determined in the fourth step in synchronization with the signal from the operation signal detecting means at regular time intervals (several minutes to several hours depending on the importance of the monitoring device). Monitor and detect and identify abnormalities.

  6th step: While the monitoring in the 5th step is continued, the scan plane is scanned while the two-dimensional map C is being scanned at a time interval longer than the monitoring interval in the 5th step (for example, once a day). Where the elevation angle is changed by 1 degree, a three-dimensional scan is performed within the elevation angle range overlooking the medical accelerator device clarified in the first step, and the gain other than the specific location in the fourth step becomes the maximum value The electromagnetic field intensity is measured, and an abnormal part other than the part specified in the fourth step is detected and specified.

  Here, the predetermined one direction monitored by the monitoring map determined in the fourth step is on one direction line. As described above, when the monitoring target part is relatively close to the distance between the patch antennas, the monitoring target part can be represented by a hyperbola or a hyperboloid with the positions of the two patch antennas as the focal points. When two or more pairs of patch antennas (consisting of two patch antennas) are used, two or more hyperbolas or hyperboloids can be obtained, so that the monitoring target part can be expressed not as a direction but as a position (focus) itself. Therefore, the position (focus) can be specified on one predetermined direction line to be monitored using two or more pairs of patch antennas, and the position of the monitoring target part can be specified. In the case where there are a plurality of monitoring target parts on a predetermined one direction line, monitoring is performed while sequentially focusing the plurality of parts in a two-dimensional scan. At this time, control is performed so that the focus point changes automatically and continuously so as to cover a predetermined area. Further, the predetermined one direction may be changed continuously in one direction so that the focus point covers a predetermined range in one direction. Furthermore, if three or more pairs of patch antennas are used, a three-dimensional position can be specified, so that the installation position of the patch array antenna can be freely selected.

  In the above-described abnormality monitoring apparatus for electric equipment, the antenna directivity is controlled without mechanically changing the antenna direction, that is, the antenna directivity direction is controlled to monitor a plurality of monitoring target parts and an abnormality occurs. The location can be identified. Further, the direction without the gain of the antenna can be varied. Therefore, such an abnormality monitoring device for electrical equipment generates electromagnetic waves due to insulation abnormalities such as partial discharges of power equipment at substations and electrostatic discharges at factory production lines, and at which positions it is generated. It can be widely applied when monitoring whether or not it is distinguished from noise. In particular, it is suitable for application to an abnormality monitoring device of an accelerator device having many noise sources, for example, a medical accelerator device. In the case of an abnormality monitoring device for a medical accelerator device, preventive maintenance can be performed in advance by predicting a failure, and accidental shutdown of the device can be avoided. It has a great effect on performance. Being able to treat patients as planned has great economic benefits and improves social responsibility to protect patient lives. In addition, the case where two or four patch antennas are illustrated has been described, but it goes without saying that the same effect can be obtained with two or more patch antennas.

DESCRIPTION OF SYMBOLS 1 Accelerator apparatus 2 Abnormality monitoring apparatus 12 Accelerator system 13 Power supply (A)
14 Power supply (B) 15 Power supply (C)
16 Power supply (D) 17 Power supply (E)
18 High-voltage cable 19 Power cable 20 Patch array antenna 21 High-frequency coaxial cable 22 Electromagnetic wave detector 23 Electromagnetic wave detection means

24 signal processing means 25 monitoring means 26 high voltage signal detection means 27 signal detection cable 28 high voltage signal monitor 31 dielectric substrate 32 excitation patch 33 feeding microstrip line 34 feeding point 35 ground electrode 36 non-excitation patch 37 dielectric (B)
38 Reinforcement plate 39 Air gap

40 Stop Hole 41 Screw Hole 42 Set Screw 51 Ion Source 52 Incident System 53 Acceleration System 54 Exit System 55 Beam Transport System 56 Irradiation System 57 Operation Signal Detection Unit 58 Network (a) 59 Signal Processing Unit (b)
60 Monitoring terminal 61 Network (b)
62 HUB 63 Phase converter 64 Controller 65 Synthesizer 66 Amplitude converter 67 Hyperbola 71 Noise source

Claims (6)

An array antenna having a plurality of patch antennas for detecting electromagnetic waves associated with partial discharges caused by an insulation abnormality in a plurality of high voltage generation units or high voltage application units of an electrical device;
A phase converter connected to the patch antenna for shifting the phase of the output of the patch antenna;
A plurality of amplitude converters respectively connected to the plurality of patch antennas;
The phase shift amount of the phase converter is controlled according to the direction from the plurality of patch antennas of each of the plurality of high voltage generation units or high voltage application units, and the amplitudes of the plurality of amplitude converters are A controller that controls the direction of electromagnetic waves received by a plurality of patch antennas ;
A synthesizer including outputs of the patch antennas whose phase shift amount is controlled, and combining outputs of the plurality of patch antennas whose amplitudes are controlled ,
Controlling the amplitude of the plurality of amplitude converters according to the specific direction of the electromagnetic wave received by the plurality of patch antennas, and having directivity in the specific direction of the electromagnetic wave,
An abnormality monitoring apparatus for an electrical device that detects an insulation abnormality of each of the plurality of high voltage generation units or high voltage application units based on an output of the combiner. An array antenna having a plurality of patch antennas for detecting electromagnetic waves associated with partial discharges caused by an insulation abnormality in a plurality of high voltage generation units or high voltage application units of an electrical device;
A plurality of phase converters respectively connected to the plurality of patch antennas and respectively shifting phases of outputs of the plurality of patch antennas;
A plurality of amplitude converters respectively connected to the plurality of patch antennas;
The phase shift amount of the plurality of phase converters is controlled according to the direction from the plurality of patch antennas of each of the plurality of high voltage generation units or high voltage application units, and the amplitudes of the plurality of amplitude converters are controlled. A controller for controlling according to the direction of electromagnetic waves received by the plurality of patch antennas ;
A synthesizer including outputs of the plurality of patch antennas whose phase shift amount is controlled, and combining outputs of the plurality of patch antennas whose amplitude is controlled ;
Controlling the amplitude of the plurality of amplitude converters according to the specific direction of the electromagnetic wave received by the plurality of patch antennas, and having directivity in the specific direction of the electromagnetic wave,
An abnormality monitoring apparatus for an electrical device that detects an insulation abnormality of each of the plurality of high voltage generation units or high voltage application units based on an output of the combiner. The array antenna is a patch array antenna composed of a plurality of patch antennas that are paired with an excitation patch and a non-excitation patch that is disposed opposite to the excitation patch and has a larger area than the excitation patch. The abnormality monitoring apparatus for an electric device according to claim 1 or 2, characterized in that:   The patch antenna detects an electromagnetic wave associated with a partial discharge generated due to an insulation abnormality in the high voltage generation unit or the high voltage application unit in synchronization with an operation signal detected by an operation signal detection unit. The abnormality monitoring device for an electric device according to claim 1 or 2, wherein abnormality detection is performed. Two or more pairs of patch antennas composed of the two patch antennas are provided , and the phase shift amount of the phase converter connected to each pair of patch antennas is controlled to identify the position of the monitoring target part. The abnormality monitoring device for an electrical device according to any one of claims 1 to 4 . The abnormality monitoring device for an accelerator device according to any one of claims 1 to 5 , wherein the electrical device is an accelerator device.

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