UHF detection apparatus capable of performing passive calibration and active calibration, partial discharge monitoring device, and cluster

Abstract

Disclosed in the present invention are a UHF detection apparatus and a partial discharge monitoring device comprising same, and a partial discharge monitoring device cluster. The UHF detection apparatus comprises a UHF signal receiving unit for acquiring a UHF high-frequency electromagnetic wave signal of a power system, a frequency sweeping and band selection unit and a main control unit. The main control unit controls operations of the frequency sweeping and band selection unit to perform passive calibration and active calibration. During passive calibration, the frequency sweeping and band selection unit performs frequency sweeping on all bands within a specific bandwidth range to obtain a swept-frequency signal, and the main control unit processes the swept-frequency signal to obtain a passive swept-frequency data feature, and uses the passive swept-frequency data feature as passive calibration parameters for environmental noise and interference signals. In a measurement working mode, on the basis of the passive calibration parameters, the frequency sweeping and band selection unit selects a UHF high-frequency electromagnetic wave signal of a specific band and outputs same. The present invention can effectively prevent UHF high-frequency electromagnetic wave signals from being affected by environmental noise and interference signals, thereby significantly improving the accuracy of detecting UHF high-frequency signals generated by partial discharge, and reducing the false alarm rate.

Description

A UHF detection device, partial discharge monitoring device and cluster capable of passive and active calibration TECHNICAL FIELD

[0001] The present application belongs to the technical field of fault detection of power systems, and particularly relates to a UHF detection device, partial discharge monitoring device and cluster capable of passive and active calibration for power systems. BACKGROUND

[0002] In industrial production and civil life scenarios, power systems are an essential part. Ensuring the safe and stable operation of power systems is an important way to ensure the good development of various industrial production and livelihood projects. China's power system and power Internet of Things system are in a rapid development stage, and the scale of power systems and related facilities is rapidly increasing. The safety, stability, reliability and economy of power systems and power Internet of Things systems have higher requirements for the safety, stability, reliability and economy of power systems and power Internet of Things systems. The insulation performance of power equipment is related to the stable operation of the entire power system. Partial discharge is one of the important manifestations of the lack of insulation performance of power equipment, and the proportion of partial discharge in various fault manifestations of power systems is more than 80%. Partial discharge is also a major factor affecting the insulation performance of power equipment. Each partial discharge will cause the insulation performance of power equipment to decline to varying degrees. Monitoring partial discharge is the main method for testing the insulation performance of power equipment.

[0003] During the process of partial discharge of electrical equipment, ultra-wideband high-frequency electromagnetic wave signals are generated, and the partial discharge state of electrical equipment can be reflected by monitoring and analyzing the high-frequency electromagnetic wave signals. The existing UHF detection device mainly detects electromagnetic wave signals of 300-1500Mhz. Due to the presence of environmental noise and electromagnetic interference signals of various frequency bands (such as various communication frequency bands) in the monitoring environment, the UHF detection device will collect environmental noise and interference signals together. When the interference signal is enhanced, the detection processing will output a relatively high relative power value, so that even if the power system does not have partial discharge, the UHF detection device will still feedback partial discharge alarm information, resulting in false positives.

[0004] In addition, when a GHz high-speed ADC is used to sample the UHF high-frequency electromagnetic wave signals generated by partial discharge and perform digital signal analysis and processing, due to the unknown nature of environmental noise and the differences between different equipment and different types of partial discharge, the signal analysis algorithm and related parameters are not perfect enough in the process of digital analysis of UHF high-frequency electromagnetic wave signals, and cannot adapt to different monitoring environments. Moreover, when some interference signals occur, false positives are also prone to occur.

[0005] A UHF partial discharge identification method based on shape, energy and statistical characteristics is disclosed in Chinese patent application CN118152942A, which includes a step of calibrating UHF partial discharge characteristic quantities. However, this scheme mainly calibrates from the feature recognition method, lacks analysis of UHF signals in different frequency bands, and therefore its accuracy is insufficient, and it cannot effectively shield environmental noise and interference signals, and still has many false positives when environmental noise and interference signals are strong. TECHNICAL PROBLEM

[0006] The technical problem solved by the present application is that existing UHF detection devices and partial discharge monitoring equipment are greatly affected by environmental noise and interference signals when detecting UHF high-frequency electromagnetic wave signals generated by partial discharge, and have a high probability of false positives. TECHNICAL SOLUTION

[0007] To solve the above technical problems, the first aspect of the present application proposes a UHF detection device for detecting UHF high-frequency electromagnetic wave signals generated by partial discharge in a power system. The UHF detection device comprises: a UHF signal receiving unit for collecting UHF high-frequency electromagnetic wave signals of the power system; a sweep selection frequency unit for sweeping or selecting the UHF high-frequency electromagnetic wave signals; and a main control unit for controlling the operation of the sweep selection frequency unit, so that the UHF detection device has a calibration mode and a measurement mode:

[0008] The calibration mode includes a passive calibration mode, in which there is no UHF high-frequency electromagnetic wave signal generated by partial discharge, the sweep selection frequency unit sweeps all frequency bands in a specific bandwidth range to obtain a sweep signal, and the main control unit processes the sweep signal to obtain passive sweep data characteristics, and the passive sweep data characteristics are used as passive calibration parameters of environmental noise and interference signals.

[0009] In the measurement mode, the sweep selection frequency unit selects UHF high-frequency electromagnetic wave signals of a specific frequency band in the specific bandwidth range according to the passive calibration parameters for output, and the main control unit processes the output UHF high-frequency electromagnetic wave signals to determine whether the power system has UHF high-frequency electromagnetic wave signals generated by partial discharge.

[0010] According to the preferred embodiment of the present application, the UHF detection device further comprises a signal generation unit for generating simulated UHF high-frequency electromagnetic wave signals for active calibration. Moreover, the calibration mode further includes an active calibration mode,

[0011] In the active calibration mode, the sweep-frequency unit selects a specific frequency band in the specific bandwidth range according to the passive calibration parameter obtained in the passive calibration mode; the signal generation unit generates a simulated UHF high-frequency electromagnetic wave signal according to the selected specific frequency band; the sweep-frequency unit outputs the UHF high-frequency electromagnetic wave signal of the specific frequency band containing the simulated UHF high-frequency electromagnetic wave signal and environmental noise and interference signals; and the master control unit processes the UHF high-frequency electromagnetic wave signal of the specific frequency band to obtain an active sweep-frequency data feature, and takes the active sweep-frequency data feature as an active calibration parameter of the coexistence of a partial discharge signal and environmental noise and interference signals.

[0012] In the measurement working mode, the sweep-frequency unit selects the UHF high-frequency electromagnetic wave signal of a specific frequency band in the specific bandwidth range for output according to the passive calibration parameter, and the master control unit processes the output UHF high-frequency electromagnetic wave signal to determine whether the power system has a partial discharge generated UHF high-frequency electromagnetic wave signal.

[0013] According to a preferred embodiment of the present application, the UHF detection device further comprises a filter unit for filtering the UHF high-frequency electromagnetic wave signal received by the UHF signal receiving unit to allow the UHF high-frequency electromagnetic wave signal of the specific bandwidth range to pass through.

[0014] According to a preferred embodiment of the present application, the UHF detection device further comprises a gain control unit for automatically gain processing the UHF high-frequency electromagnetic wave signal of the specific bandwidth range filtered by the filter unit to control the signal strength within a specific range.

[0015] According to a preferred embodiment of the present application, the UHF detection device further comprises an ADC unit for analog-digital conversion of the UHF high-frequency electromagnetic wave signal output by the sweep-frequency unit to convert the analog UHF high-frequency electromagnetic wave signal into a digital UHF high-frequency electromagnetic wave signal; and the master control unit is configured to process the digital UHF high-frequency electromagnetic wave signal output by the ADC unit in the calibration working mode and the measurement working mode to determine whether the power system has a partial discharge.

[0016] According to a preferred embodiment of the present application, the master control unit determines whether the power system has a partial discharge by determining whether the digital UHF high-frequency electromagnetic wave signal has a partial discharge characteristic waveform.

[0017] According to the preferred embodiment of the present application, the UHF detection device further comprises a detection unit for detecting the power of the UHF high-frequency electromagnetic wave signal output by the frequency scanning unit; and the main control unit is configured to determine whether there is partial discharge in the power system by comparing the relative power of the UHF high-frequency electromagnetic wave signal output by the detection unit in the calibration mode and the measurement mode.

[0018] The second aspect of the present application provides a partial discharge monitoring device comprising the UHF detection device.

[0019] According to the preferred embodiment of the present application, the partial discharge monitoring device further comprises a micro-processing device as the main control unit of the UHF detection device.

[0020] According to the preferred embodiment of the present application, the partial discharge monitoring device further comprises a TEV detection device for detecting the TEV signal in the power system under the control of the micro-processing device.

[0021] According to the preferred embodiment of the present application, the micro-processing device is further configured to control the operation of the TEV detection device so that the TEV detection device has a calibration mode and a measurement mode.

[0022] The calibration mode is a passive calibration mode in which the micro-processing device processes the TEV signal in the absence of the TEV signal generated by the partial discharge to obtain passive TEV data characteristics, and the passive TEV data characteristics are used as TEV passive calibration parameters of the environmental noise and interference signal.

[0023] In the measurement mode, the micro-processing device processes the TEV signal obtained by the TEV detection device according to the TEV passive calibration parameters to determine whether there is a TEV signal generated by the partial discharge in the power system.

[0024] According to the preferred embodiment of the present application, the partial discharge monitoring device further comprises an ultrasonic detection device for detecting the ultrasonic signal in the power system under the control of the micro-processing device.

[0025] According to the preferred embodiment of the present application, the micro-processing device of the partial discharge monitoring device is further configured to control the operation of the ultrasonic detection device so that the ultrasonic detection device has a calibration mode and a measurement mode.

[0026] The calibration mode is a passive calibration mode in which the micro-processing device processes the ultrasonic signal in the absence of the ultrasonic signal generated by the partial discharge to obtain passive acoustic fingerprint data characteristics, and the passive acoustic fingerprint data characteristics are used as acoustic fingerprint passive calibration parameters of the environmental noise and interference signal.

[0027] In the measurement mode, the micro-processing device processes the ultrasonic signal obtained by the ultrasonic detection device according to the voiceprint passive calibration parameter to determine whether the power system has ultrasonic signal generated by partial discharge.

[0028] According to the preferred embodiment of the present application, the partial discharge monitoring device further comprises a UWB wireless communication device for transmitting data externally under the control of the micro-processing device.

[0029] The second aspect of the present application provides a cluster of partial discharge monitoring devices, which is composed of a plurality of the partial discharge monitoring devices, and the UWB wireless communication devices of the partial discharge monitoring devices are used for time synchronization. Advantages

[0030] The UHF detection device, the partial discharge monitoring device and the cluster of the present application can perform passive calibration and / or active calibration on the UHF high-frequency electromagnetic wave detection device, and perform adaptive frequency selection detection of the UHF signal according to the calibration parameter, which can greatly avoid the influence of environmental noise and interference signals on the UHF high-frequency electromagnetic wave signal, thereby greatly improving the accuracy of UHF high-frequency signal detection caused by partial discharge and reducing the false alarm rate. BRIEF DESCRIPTION OF DRAWINGS

[0031] Fig. 1 is a functional module architecture diagram of the first embodiment of the UHF detection device of the present application.

[0032] Fig. 2 is a functional schematic diagram of the first embodiment of the UHF detection device of the present application for multi-channel detection.

[0033] Fig. 3 is a functional module architecture diagram of the second embodiment of the UHF detection device of the present application.

[0034] Fig. 4 is a functional module architecture diagram of the first embodiment of the partial discharge monitoring device comprising the UHF detection device of the present application. Embodiments of the present application

[0035] To solve the above technical problems, the present application provides a UHF detection device capable of passive calibration and preferably having passive and active calibration functions and capable of frequency selection detection, which is used for detecting UHF high-frequency electromagnetic wave signals generated by partial discharge in a power system. The UHF detection device comprises a UHF signal receiving unit, a frequency scanning unit and a master control unit. It should be noted that the high frequency referred to in the present application refers to a frequency range of 300MHz~3GHz. The high-frequency electromagnetic wave signal generated by partial discharge in the range of 300MHz~3GHz is a transient signal in the time domain and a super wide frequency signal in the frequency domain.

[0036] The sweep selection frequency unit is used for sweeping or selecting the UHF high frequency electromagnetic wave signal in the power system collected by the UHF signal receiving unit, and the master control unit is used for controlling the operation of the sweep selection frequency unit.

[0037] The master control unit is the core control unit of the UHF detection device, and is used for controlling the operation of each unit of the UHF detection device. In the present application, the control of the sweep selection frequency unit by the master control unit is the core of the present application. The master control unit controls the action of the sweep selection frequency unit so that the UHF detection device has a calibration mode and a measurement mode.

[0038] The calibration mode is a designated calibration process, that is, when the UHF detection device is installed or the environment changes, the UHF detection device is calibrated so as to better adapt to the current environment, and the UHF high frequency electromagnetic wave signal is set according to the current environment. In the present application, the calibration mode includes a passive calibration mode and an active calibration mode, or at least one of the calibration modes.

[0039] The passive calibration mode refers to the calibration of the UHF detection device in the absence of UHF high frequency electromagnetic wave signals generated by local discharge. At this time, the master control unit controls the sweep selection frequency unit to sweep, that is, to sweep all frequency bands in a specific bandwidth range to obtain a sweep signal. The specific bandwidth range is, for example, 300MHz~3GHz, or 300MHz~2.2GHz. The master control unit processes the sweep signal to obtain passive sweep data characteristics, and uses the passive sweep data characteristics as passive calibration parameters of environmental noise and interference signals.

[0040] The measurement working mode refers to a mode in which the UHF detection device is in normal working after calibration, to detect the UHF high-frequency electromagnetic wave signals generated by partial discharge. In the measurement working mode, the sweep selection frequency unit performs frequency selection operation, and according to the frequency band distribution of the calibrated environmental noise and interference signals, the frequency selection parameters of the sweep selection frequency unit are actively configured, so that the sweep selection frequency unit avoids a large output of the environmental noise and interference signals, and selects a frequency band that can realize the detection of the partial discharge UHF high-frequency electromagnetic wave signals, while avoiding the background noise and environmental interference signals as much as possible (for example, after sweeping the frequency band of 300Mhz to 2.2Ghz, it is found that the signals near 433Mhz, 860Mhz, 1.2Ghz and 2Ghz are relatively strong, but at this time, the electrical equipment is not running, or no partial discharge occurs, so the frequency signals are mainly environmental interference signals, and the frequency selector will actively avoid the output of these signals, and the frequency selection output is ch1: 330MHz~350MHz, ch2: 660MHz~700MHz, ch3: 1400MHz~1460MHz, ch4: 1790MHz~1850MHz, so that these frequency selection channels can avoid the frequency bands with strong electromagnetic interference signals as much as possible, and since the partial discharge is a super wide frequency signal, the selected frequency band can still realize the detection of the partial discharge high-frequency electromagnetic signals). That is, the sweep selection frequency unit outputs the UHF high-frequency electromagnetic wave signals in a specific frequency band in the specific bandwidth range according to the passive calibration parameters. The main control unit processes the output UHF high-frequency electromagnetic wave signals to determine whether the UHF high-frequency electromagnetic wave signals generated by the partial discharge exist in the power system. The processing and determination of the UHF high-frequency electromagnetic wave signals by the main control unit can be performed by using the existing technology, and will not be described in detail here.

[0041] According to the preferred embodiment of the present application, the calibration working mode can also include an active calibration mode, in which the UHF detection device is also configured with a signal generation unit, and the signal generation unit generates simulated UHF high-frequency electromagnetic wave signals. At this time, the sweep selection frequency unit has realized the frequency selection configuration of the frequency band according to the passive calibration mode, and the frequency selection frequency band can avoid environmental signal interference as much as possible, but in different environments, environmental interference signals cannot be completely avoided. The signal generation unit generates UHF high-frequency electromagnetic wave signals within the frequency selection range of the sweep selection frequency unit, and then the sweep selection frequency unit outputs the frequency band within the specific bandwidth range to obtain the environmental interference signals and the simulated UHF high-frequency electromagnetic wave signals within the frequency selection range. The main control unit processes the signals of the output frequency band to obtain the active sweep frequency data characteristics, and takes the active sweep frequency data characteristics as the active calibration parameters of the simultaneous existence of the partial discharge signals and the environmental noise and interference signals.

[0042] When the active calibration is included, in the measurement mode, the sweep frequency selection unit selects the UHF high frequency electromagnetic wave signal in the specific frequency band in the specific bandwidth range according to the passive calibration parameter to output, and the host control unit further processes the output UHF high frequency electromagnetic wave signal according to the active calibration parameter to determine whether the power system has the UHF high frequency electromagnetic wave signal generated by the partial discharge. Since the active calibration is performed, the signal characteristics when the partial discharge UHF signal and the environmental interference signal exist at the same time are simulated and emulated, so that when the system judges the partial discharge signal, the emulated characteristic parameters can be used as one of the judgment bases.

[0043] In order to make the object, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with specific embodiments and with reference to the drawings.

[0044] Fig. 1 is a functional module architecture diagram of the first embodiment of the UHF detection device of the present application. As shown in Fig. 1, the UHF detection device includes a host control unit, a first ADC unit, a detection unit, a sweep frequency selection unit, a first filter unit, a first gain control unit and a UHF signal receiving unit.

[0045] The UHF signal receiving unit is used to receive the UHF high frequency electromagnetic wave signal, which is usually realized by a UHF antenna. The signal received by the UHF antenna is transmitted to the first filter unit.

[0046] The first filter unit of this embodiment is realized by a band-pass filter, which only allows the electromagnetic wave signal in the range to pass, for example, can be configured to pass only the electromagnetic wave signal in the frequency band range of 300MHz~2.2GHz. If other frequency band ranges are needed, the band-pass filter can also be adjusted. The signal output by the band-pass filter is transmitted to the first gain control unit.

[0047] The first gain control unit is used to perform gain or attenuation processing on the high frequency electromagnetic wave signal output by the first filter unit. This functional unit can be an automatic gain controller, which automatically detects whether the intensity of the collected electromagnetic wave signal is too high or too low. For the electromagnetic wave with too high signal energy, automatic attenuation processing is performed to prevent damage to the rear-end circuit; and for the electromagnetic wave with relatively low signal intensity, automatic gain processing is performed to facilitate the analysis and processing of the subsequent circuit. The signal output by the automatic gain controller is transmitted to the sweep frequency selection unit.

[0048] The sweep selection frequency unit is one of the core functional units, which is composed of a frequency sweeper and a frequency band selector in this embodiment, and performs the frequency sweeping function or the frequency band selection function under the control of the master control unit. When the master control unit controls the frequency sweeper of the sweep selection frequency unit to work for frequency sweeping, the frequency sweeper outputs a wideband range electromagnetic wave signal (such as a wideband signal of 300-2200 MHz) adjusted by the first gain control unit. When the master control unit controls the frequency band selector of the sweep selection frequency unit to work for frequency band selection, the working parameters of the frequency band selector are configured to selectively output electromagnetic wave signals of specific frequency bands.

[0049] Whether working as a frequency sweeper or a frequency band selector, the high-frequency electromagnetic wave signal output by the sweep selection frequency unit enters the detection unit on one hand and enters the first ADC unit on the other hand. In this embodiment, the detection unit is composed of a detector or a detection circuit, which is used for detecting the average power of the signal and outputting to the master control unit. The first ADC unit is composed of a high-speed analog-to-digital converter, which is used for high-band AD conversion of the signal and sending to the master control unit.

[0050] The master control unit is used for controlling the execution of each functional unit or device on one hand, and for processing the signals received by it on the other hand, so as to calibrate the UHF device or determine whether there is a UHF high-frequency electromagnetic wave signal generated by partial discharge in the power system during measurement. For example, it performs time-domain digital sampling on the digital high-frequency electromagnetic wave signal after high-speed AD conversion, and performs subsequent digital signal analysis and processing.

[0051] Figure 2 is a functional schematic diagram of the multi-channel detection of the first embodiment of the UHF detection device of the present application. As shown in Figure 2, in this embodiment, the master control unit actively configures the working parameters of the frequency band selector of the sweep selection frequency unit according to the frequency band distribution of the calibrated environmental noise and interference signals, so that the frequency band selector avoids a large output of environmental noise and interference signals, selects a frequency band that can realize the detection of UHF high-frequency electromagnetic wave signals generated by partial discharge, and at the same time, maximizes the avoidance of the frequency band of environmental noise and interference signals. As shown in Figure 2, four channels, i.e. the selection of four frequency bands of ch1: 330-350 MHz, ch2: 660-700 MHz, ch3: 1400-1460 MHz, and ch4: 1790-1850 MHz. In other embodiments, the number of frequency bands and the frequency band bandwidth should be adjusted according to the environmental noise and interference signals of the application site.

[0052] The multi-band UHF high-frequency electromagnetic wave signal output after selection by the frequency band selector has a high signal-to-noise ratio. This signal enters a multi-channel detector, which serves as the detection unit, outputting the relative power values ​​of the multi-band UHF high-frequency electromagnetic wave signal; simultaneously, it enters a high-speed AD converter for time-domain waveform acquisition. In this way, the detected power value and time-domain waveform data of the UHF high-frequency electromagnetic wave signal acquired by the main control unit can minimize the influence of environmental noise and interference signals, thereby improving the signal-to-noise ratio and monitoring accuracy of the UHF detection device and reducing false alarms.

[0053] Figure 3 is a functional block architecture diagram of a second embodiment of the UHF detection device of the present invention. As shown in Figure 3, compared with the first embodiment, the UHF detection device of this embodiment further includes a signal generation unit. The signal generation unit is used to generate a simulated UHF high-frequency electromagnetic wave signal, which is used for active calibration.

[0054] The signal generation unit preferably transmits electromagnetic wave signals in a specific frequency band, and the frequency range and number of bands can be configured and adjusted. For example, the signal generation unit is a frequency selector, in which four channels of electromagnetic wave signals are selected under the control of the main control unit: ch1: 330MHz~350MHz, ch2: 660MHz~700MHz, ch3: 1400MHz~1460MHz, and ch4: 1790MHz~1850MHz. After the signals in these four frequency bands are transmitted, the main control unit controls the UHF signal receiving unit and the frequency sweeping unit of the UHF detection device to work, and the working mode is the same as the calibration working mode and measurement working mode mentioned above. This invention actively selects and transmits electromagnetic wave signals in a specific frequency band and a certain number of frequency bands into the monitoring environment, and collects the UHF signal characteristics collected by the system's UHF signal receiving unit when the transmitted electromagnetic wave signals coexist with environmental noise and interference signals, and records these signal characteristics.

[0055] The calibration process for this UHF high-frequency electromagnetic wave signal is called "active calibration". It simulates the monitoring status of the UHF high-frequency electromagnetic wave signal generated by partial discharge under environmental noise and interference signal conditions by actively transmitting electromagnetic wave signals in the frequency band where partial discharge exists.

[0056] In other words, in this second embodiment, the UHF detection device can also perform active calibration. In active calibration mode, the signal generation unit generates a simulated UHF high-frequency electromagnetic wave signal. At this time, the frequency sweeper in the frequency sweeping unit sweeps all frequency bands within a specific bandwidth range to obtain a swept frequency signal containing the simulated UHF high-frequency electromagnetic wave signal. The main control unit processes the swept frequency signal to obtain active swept frequency data characteristics, and uses these active swept frequency data characteristics as active calibration parameters where partial discharge signals, environmental noise, and interference signals coexist.

[0057] In the measurement mode, the frequency selection unit selects the UHF high frequency electromagnetic wave signal of a certain frequency band in the certain bandwidth range according to the passive calibration parameter, and the main control unit further processes the output UHF high frequency electromagnetic wave signal according to the active calibration parameter to determine whether the power system has the UHF high frequency electromagnetic wave signal generated by the partial discharge. Through passive calibration, the frequency band channel which can avoid the massive output of environmental interference signals and detect the partial discharge UHF signal is selected, and the signal-to-noise ratio is improved; through active calibration, the signal characteristics when the partial discharge UHF signal and the environmental interference signal of the frequency selection channel exist at the same time are simulated, so that the system uses the simulated characteristic parameters as one of the judgment bases when judging the partial discharge signal, which is convenient for extracting the partial discharge signal characteristics and also improves the signal-to-noise ratio.

[0058] Fig. 4 is a functional module architecture diagram of a first embodiment of a partial discharge monitoring device comprising the UHF detection device of the present application. As shown in Fig. 4, the partial discharge monitoring device comprises the second embodiment of the UHF detection device, which is circled by a dashed line and indicated by reference numeral 1. And the main control unit of the UHF detection device is realized by the micro processing device 2.

[0059] In addition, as shown in Fig. 4, the partial discharge monitoring device of this embodiment further comprises a TEV (ground wave) detection device 3, an ultrasonic wave detection device 4, a UWB wireless communication device and a storage unit.

[0060] The TEV detection device detects the TEV signal in the power system under the control of the micro processing device. The micro processing device controls the operation of the TEV detection device, so that the TEV detection device also has a calibration mode and a measurement mode: the calibration mode is a passive calibration mode, in which the micro processing device processes the TEV signal in the absence of the TEV signal generated by the partial discharge to obtain passive TEV data characteristics, and takes the passive TEV data characteristics as the TEV passive calibration parameter of the environmental noise and interference signal; in the measurement mode, the micro processing device processes the TEV signal obtained by the TEV detection device according to the TEV passive calibration parameter to determine whether the power system has the TEV signal generated by the partial discharge.

[0061] The TEV detection device comprises a TEV signal receiving unit, a second filtering unit, a second gain control unit and a second ADC unit. The second filtering unit of this embodiment is also realized by a band-pass filter, which is similar to the band-pass filter of the first filtering unit, and only allows the TEV signal in the range to pass. The signal output by the band-pass filter is transmitted to the second gain control unit.

[0062] The second gain control unit is used for gain or attenuation processing of the TEV signal output by the second filter unit. The function unit can also be an automatic gain controller, which automatically detects whether the intensity of the collected TEV signal is too high or too low. For the TEV signal with too high signal energy, automatic attenuation processing is performed to prevent damage to the backend circuit. For the TEV signal with relatively low signal intensity, automatic gain processing is performed to facilitate analysis and processing of the subsequent circuit. The signal output by the automatic gain controller is transmitted to the second ADC unit.

[0063] The second ADC unit is also composed of a high-speed analog-to-digital converter, which is used for high-band AD conversion of the signal and then sends the signal to the host control unit.

[0064] Similarly, the ultrasonic detection device detects ultrasonic signals in the power system under the control of the microprocessing device. The microprocessing device controls the operation of the ultrasonic detection device, so that the ultrasonic detection device also has a calibration mode and a measurement mode: the calibration mode is also a passive calibration mode, in which the microprocessing device processes the passive acoustic fingerprint data features obtained in the absence of the ultrasonic signals generated by the partial discharge, and takes the passive acoustic fingerprint data features as the acoustic fingerprint passive calibration parameters of the environmental noise and interference signals; in the measurement mode, the microprocessing device processes the ultrasonic signals obtained by the ultrasonic detection device according to the acoustic fingerprint passive calibration parameters to determine whether the power system has ultrasonic signals generated by the partial discharge.

[0065] The ultrasonic detection device is composed of an ultrasonic detection unit, such as an acoustic fingerprint microphone (acoustic fingerprint MIC).

[0066] The UWB wireless communication device is used for transmitting data to the outside under the control of the microprocessing device. UWB is a kind of ultra-wideband wireless communication technology, which uses very large bandwidth to transmit data, and uses extremely short pulse signals or wideband continuous wave signals to realize high-speed data transmission. Because the UWB signal is distributed very widely in the frequency spectrum, it has relatively small influence on narrowband interference and strong anti-interference performance. In the present application, since the UHF, TEV, and ultrasonic signals are all digitally sampled, stored, and transmitted, the use of UWB communication can quickly realize the transmission function of a large amount of data without interfering with the collection of partial discharge UHF high-frequency electromagnetic wave signals. In addition to the USB wireless communication device, in the present embodiment or the embodiments thereof, LoRa and WIFI communication devices can also be included as alternatives or supplements to the UWB wireless communication device.

[0067] Adopt UWB wireless communication, can realize μs level even ns level time synchronization, can realize time synchronization function between multiple partial discharge monitoring devices, for need multi-monitoring device joint monitoring, and do data fusion analysis has very good promotion function. That is to say, the partial discharge monitoring device of the application can also form a partial discharge monitoring device cluster, each partial discharge monitoring device is arranged in a part of the power system, the UWB wireless communication device between each partial discharge monitoring device can realize time synchronization, thereby realizing the synchronous monitoring between each partial discharge monitoring device. The time synchronization between the UWB wireless communication device can be realized by the prior art, which will not be described here.

[0068] The storage unit is used for storing data from the microprocessor or the host unit and supporting reading by the host unit, and the stored data includes UHF high-frequency electromagnetic wave signals, TEV signals, ultrasonic signals and the like, including calibration data recorded during calibration, measurement data obtained during measurement, and data for partial discharge judgment by the microprocessor or the host unit.

[0069] The partial discharge monitoring device of the embodiment further includes a power supply, a shell and the like, which are all conventional components and will not be described here.

[0070] The UHF detection device of the above-mentioned embodiment of the partial discharge monitoring device has a sweep multi-band selection function, and the frequency band selector of the sweep selection unit realizes the simultaneous output of the wideband electromagnetic wave signals collected by the UHF antenna into multiple frequency bands, and the number of frequency bands and the bandwidth of the frequency bands are automatically configured according to the on-site monitoring environment, so that the number, bandwidth and frequency band interval of the output frequency bands can avoid environmental noise and interference signals in the monitoring environment to the maximum extent. Thus, the partial discharge monitoring device can effectively monitor the partial discharge while avoiding the influence of environmental noise and interference signals, so as to improve the signal-to-noise ratio and reduce the false judgment of the partial discharge.

[0071] The ultrasonic detection device of the above-mentioned partial discharge monitoring device monitors the acoustic fingerprint information in the environment in the state of no partial discharge and makes array collection, and after the microprocessor analyzes the acoustic fingerprint data in time domain and frequency domain, the acoustic fingerprint data is used as the background noise and interference signal of the monitoring environment to realize passive calibration of the ultrasonic signal. In the subsequent monitoring process of the partial discharge, the characteristics of the calibrated environmental noise and interference signal are compared in real time, so as to avoid the false alarm caused by monitoring the partial discharge by simply judging the presence or absence and intensity of the ultrasonic signal.

[0072] The partial discharge TEV monitoring block of the above-mentioned partial discharge monitoring device collects the TEV signal in the monitoring environment in the state without partial discharge, and the TEV signal is analyzed by the microprocessor in time domain and frequency domain, and is taken as the monitoring environment noise and interference signal, so that the passive calibration of the TEV signal is realized. In the subsequent monitoring process of the TEV detection device on the partial discharge, the characteristics of the calibrated environmental noise and interference signal are compared in real time, so that the false alarm caused by the simple monitoring of the presence or absence and intensity of the TEV signal on the partial discharge is avoided.

[0073] The above-mentioned specific embodiments further specifically describe the purposes, technical solutions and beneficial effects of the present application, and it should be understood that the above-mentioned is only a specific embodiment of the present application and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A UHF detection device for detecting UHF high frequency electromagnetic wave signals generated by partial discharge in a power system, comprising: a UHF signal receiving unit for collecting UHF high frequency electromagnetic wave signals of the power system; a sweeping and selecting frequency unit for sweeping or selecting frequencies of the UHF high frequency electromagnetic wave signals; and a main control unit for controlling operations of the sweeping and selecting frequency unit, so that the UHF detection device has a calibration mode and a measurement mode: the calibration mode includes a passive calibration mode, in which there is no UHF high frequency electromagnetic wave signal generated by partial discharge, the sweeping and selecting frequency unit sweeps all frequency bands in a specific bandwidth range to obtain a sweeping signal, and the main control unit processes the sweeping signal to obtain passive sweeping data features, and the passive sweeping data features are used as passive calibration parameters of environmental noise and interference signals; in the measurement mode, the sweeping and selecting frequency unit selects UHF high frequency electromagnetic wave signals of specific frequency bands in the specific bandwidth range according to the passive calibration parameters, and the main control unit processes the output UHF high frequency electromagnetic wave signals to determine whether the power system has UHF high frequency electromagnetic wave signals generated by partial discharge. 2.The UHF detection device according to claim 1, further comprising a signal generating unit for generating simulated UHF high frequency electromagnetic wave signals for active calibration; the calibration mode further includes an active calibration mode, in which the sweeping and selecting frequency unit selects specific frequency bands in the specific bandwidth range according to the passive calibration parameters obtained in the passive calibration mode, the signal generating unit generates simulated UHF high frequency electromagnetic wave signals according to the selected specific frequency bands, the sweeping and selecting frequency unit outputs UHF high frequency electromagnetic wave signals of the specific frequency bands containing the simulated UHF high frequency electromagnetic wave signals and environmental noise and interference signals, and the main control unit processes the UHF high frequency electromagnetic wave signals of the specific frequency bands to obtain active sweeping data features, and the active sweeping data features are used as active calibration parameters of the coexistence of partial discharge signals and environmental noise and interference signals; in the measurement mode, the sweeping and selecting frequency unit selects UHF high frequency electromagnetic wave signals of specific frequency bands in the specific bandwidth range according to the passive calibration parameters, and the main control unit further processes the output UHF high frequency electromagnetic wave signals according to the active calibration parameters to determine whether the power system has UHF high frequency electromagnetic wave signals generated by partial discharge. 3.The UHF detection device according to claim 1 or 2, further comprising a filtering unit for filtering the UHF high frequency electromagnetic wave signals collected by the UHF signal receiving unit to allow the UHF high frequency electromagnetic wave signals in the specific bandwidth range to pass through. ​ ​ ​ ​ ​ ​ ​ 4. The UHF detection device according to claim 3, further comprising a gain control unit for automatically gain processing the UHF high frequency electromagnetic wave signal of the specific bandwidth range filtered by the filter unit, so as to control the signal strength within a specific range.

5. The UHF detection device according to claim 1 or 2, further comprising an ADC unit for analog-digital converting the UHF high frequency electromagnetic wave signal output by the sweep frequency unit, so as to convert the analog UHF high frequency electromagnetic wave signal into a digital UHF high frequency electromagnetic wave signal; the master control unit is used for processing the digital UHF high frequency electromagnetic wave signal output by the ADC unit in the calibration mode and the measurement mode, so as to determine whether the power system has partial discharge.

6. The UHF detection device of claim 5, wherein, the master control unit determines whether the power system has partial discharge by judging whether the digital UHF high frequency electromagnetic wave signal has a partial discharge characteristic waveform.

7. The UHF detection device according to claim 1 or 2, further comprising a detection unit for power detecting the UHF high frequency electromagnetic wave signal output by the sweep frequency unit; the master control unit is used for determining whether the power system has partial discharge by judging the relative power of the UHF high frequency electromagnetic wave signal output by the detection unit in the calibration mode and the measurement mode.

8. A partial discharge monitoring device comprising the UHF detection device according to claim 1 or 2.

9. The partial discharge monitoring device according to claim 8, further comprising a micro processing device as the master control unit of the UHF detection device.

10. The partial discharge monitoring device according to claim 9, further comprising a TEV detection device for detecting a TEV signal in the power system under the control of the micro processing device.

11. The corrosion monitoring apparatus of claim 10, wherein, the micro processing device is further used for controlling the operation of the TEV detection device, so that the TEV detection device has a calibration mode and a measurement mode: the calibration mode is a passive calibration mode, in which the micro processing device processes the TEV signal in the absence of the TEV signal generated by partial discharge to obtain passive TEV data characteristics, and uses the passive TEV data characteristics as TEV passive calibration parameters of environmental noise and interference signals; in the measurement mode, the micro processing device processes the TEV signal obtained by the TEV detection device according to the TEV passive calibration parameters to determine whether the power system has a TEV signal generated by partial discharge.

12. The partial discharge monitoring device according to claim 9, further comprising an ultrasonic wave detection device for detecting an ultrasonic wave signal in the power system under the control of the micro processing device.

13. The partial discharge monitoring device according to claim 12, the micro processing device is further used for controlling the operation of the ultrasonic wave detection device, so that the ultrasonic wave detection device has a calibration mode and a measurement mode: The calibration mode is a passive calibration mode, in which the micro-processing device processes the ultrasonic signal generated by the partial discharge to obtain passive acoustic print data features, and takes the passive acoustic print data features as acoustic print passive calibration parameters of environmental noise and interference signals. In the measurement mode, the micro-processing device processes the ultrasonic signal obtained by the ultrasonic detection device according to the acoustic print passive calibration parameters to determine whether the power system has the ultrasonic signal generated by the partial discharge.

14. The partial discharge monitoring device of claim 9, further comprising a UWB wireless communication device for transmitting data to the outside under the control of the micro-processing device.

15. A cluster of partial discharge monitoring devices, which is composed of a plurality of the partial discharge monitoring devices of claim 14, and the UWB wireless communication devices of the partial discharge monitoring devices are used for time synchronization.

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