High-voltage line grounding point detecting and positioning device

Abstract

The utility model provides a high-voltage line grounding point detecting and positioning device. The high-voltage line grounding point detecting and positioning device mainly comprises a transmitting device and a receiving device. The transmitting device comprises a power supply module, a signal source module, a DSP unit, an embedded ARM and an impedance ranging module; the receiving device comprises a power supply module, a DSP unit, an embedded ARM, a measurement module and a display module. The transmitting device is connected with a line to be tested and the ground, and the receiving device is handheld or carried by an unmanned aerial vehicle. The transmitting device injects a specific high-frequency signal into a to-be-detected line, then detects and calculates current and voltage signals of the to-be-detected line, and calculates impedance and compares threshold current by analyzing voltage and current values on the to-be-detected line. Therefore, whether a grounding phenomenon exists in the to-be-detected line or not is accurately judged, and a grounding point is preliminarily positioned. A receiving device moves under a line to be detected, a high-frequency electromagnetic wave signal emitted by the line is detected, and accurate positioning of a grounding point is realized by taking the power of an electromagnetic wave as a criterion.

Description

Technical Field

[0001] The utility model is a device for detecting and locating a grounding point of a high-voltage line. Background Art

[0002] Most of the existing technologies are about online detection. For example, the application publication number is CN114325476A, the application publication date is 2022.04.12, and the application number is CN202111659634.4. A grounding wire status detection device and detection method need to be connected to the line all the time and the power grid line can be powered normally to detect the grounding wire. When the power grid is out of power, these existing online detection technologies fail and the device cannot work normally.

[0003] In addition, the existing grounding wire detection technology in the power outage state can detect the type of grounding, but cannot accurately detect the location of the grounding point. For example, the application publication number: CN105137226A, application publication date: 2015.12.09, application number: CN201510469410.5, the line grounding state detection and positioning device can be used in the power outage state. However, because the device will generate uncertain grounding resistance when it is connected to the power grid, it is not possible to accurately locate the grounding point.

[0004] Therefore, a high-voltage line grounding point detection and positioning device is proposed to achieve the detection of whether the line to be tested has a grounding phenomenon and the precise positioning of the connection point when the power grid is off. Summary of the invention

[0005] A high-voltage line grounding point detection and positioning device can detect whether a line to be tested has a grounding phenomenon and accurately locate the connection point, and its operation process is simple and easy to use; it includes a transmitting device and a receiving device.

[0006] The transmitting device is connected to the circuit to be tested and the ground.

[0007] The above-mentioned receiving device is handheld or carried by a drone and moves under the line to be tested.

[0008] The above-mentioned high-voltage line grounding point detection and positioning device injects a specific high-frequency signal into the line to be tested through a transmitting device, and then detects and calculates the current and voltage signals of the line to be tested. By analyzing the voltage and current values ​​on the line to be tested, impedance calculation and threshold current comparison are performed, so as to accurately determine whether there is a grounding phenomenon in the line to be tested and preliminarily locate the connection point. The receiving device moves under the line to be tested to detect the high-frequency electromagnetic wave signal emitted by the line. If the line above the receiving device is short-circuited, the unchanged power value can be detected; if the detected power value is significantly reduced, it means that the line above the receiving device is not connected. Thereby, the accurate positioning of the grounding point can be achieved.

[0009] In one of the embodiments, the transmitting device includes a power supply module, a signal source module, a DSP unit, an embedded ARM and an impedance ranging module.

[0010] The power module filters the 12V DC battery, uses a DC isolation power module to isolate the power supply, and uses Buck step-down and Boost step-up to power the DSP unit and signal source module respectively. A 12.6V rechargeable lithium-ion battery pack can be selected, equipped with an intelligent IC protection board to stabilize the output voltage and extend the battery life. At the same time, there is a power indicator to prevent low power use.

[0011] The signal source module can generate a three-phase AC signal according to the PWM signal generated by the DSP unit, and the power inversion is realized by the IPM chip. The PSS10S92E6AG can be selected to convert the DC signal into an AC signal, and then inject it into the transmission line after filtering. At the same time, the output signal is fed back to the DSP unit in real time for adjusting and controlling the PWM, thereby improving the accuracy of the signal source.

[0012] The DSP unit can generate a PWM signal to control the signal source module to generate a three-phase AC signal of a specific frequency, and realize the measurement and protection control of voltage and current signals. TMS320F2812 can be selected, which has a built-in ADC analog-to-digital converter.

[0013] The embedded ARM communicates with the DSP unit through a serial port, calculates the current and voltage signals measured by the impedance measurement module, analyzes the voltage and current values ​​on the circuit to be tested, calculates the impedance and compares the threshold current, determines whether there is a grounding phenomenon and preliminarily locates the connection location. An ARM920T chip can be selected and embedded in the Android operating system to make the detection device intelligent.

[0014] The impedance ranging module filters, amplifies and filters again the voltage and current signals injected into the circuit to be measured, and then sends them to the embedded ARM via the DSP unit. At the same time, it compares the signals with the transformer end to provide feedback control for the error. The amplifier can be LM339.

[0015] In one embodiment, the receiving device includes a power module, a DSP unit, an embedded ARM, a measurement module and a display module.

[0016] The power module filters the 12V DC battery, uses a DC isolation power module to isolate the power supply, and powers the DSP unit through Buck step-down. A 12.6V rechargeable lithium-ion battery pack can be selected, equipped with an intelligent IC protection board to stabilize the output voltage and extend the battery life. At the same time, there is a power indicator to prevent low power use.

[0017] The DSP unit receives the DC voltage value measured by the measuring module and performs serial communication with the embedded ARM. TMS320F2812 can be selected, which has a built-in ADC analog-to-digital converter.

[0018] The embedded ARM receives the DC voltage value measured by the module, obtains the power value of the electromagnetic wave emitted by the measured line, and realizes the accurate positioning of the grounding point by detecting the change of the power value. An ARM920T chip can be selected and embedded in the Android operating system.

[0019] The measuring module converts the power value of the electromagnetic wave emitted by the circuit to be tested into a DC voltage value corresponding thereto. The power detection using this method can be unaffected by the waveform of the electromagnetic wave signal. The measuring module is composed of a tuned filter, a power divider, an attenuation module, an amplification module, a radio frequency switch, a detection circuit and a voltage follower. After the signal to be tested is filtered by the tuned filter, it is divided into three paths by the power divider: one path remains unchanged, one path is weakened by the attenuation module, and one path is enhanced by the amplification module. The radio frequency switch can select a suitable signal to output to the detection module to keep the output of the detection circuit moderate. The detection circuit converts the power value into a DC voltage value corresponding thereto. The voltage follower can reduce the influence of the subsequent circuit on the previous circuit, making the measurement more accurate. The tuned filter can be ADMV8052, the power divider can be 03KPD-2^300M-3S, the attenuation module can be PE402 programmable attenuator, the amplification module can be ADL5243 programmable gain RF amplifier, the RF switch can be RF1604 four-throw switch, the detection circuit can be AD8361 true RMS detection chip, and the voltage follower can be LM324.

[0020] The display module can display the geographical location information of the grounding point. The input voltage required for the liquid crystal display LCD is 3.3V, which can be directly connected to the embedded ARM. The input signal is a UART interface, and an HDMI 7-inch high-definition capacitive touch screen can be selected. In addition to the required power supply and ground wire, only two signal wires are required, the signal is more stable, and the design is more reliable and reasonable.

[0021] In one embodiment, the accuracy and speed of the ADC digital-to-analog converter of the DSP unit are very high, but filtering is also required before the signal is input, and a second-order bandpass filter composed of an amplifier can be used.

[0022] Compared with the prior art, the utility model has the following advantages and effects:

[0023] (1) It can accurately locate the docking location.

[0024] (2) It can be detected during power outage. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of the detection and positioning device for the grounding point of a high-voltage line of the utility model;

[0026] Figure 2 A schematic diagram of the structure of a high-voltage line grounding point detection and positioning device according to an embodiment;

[0027] Figure 3 The figure is a schematic diagram of the structure of a transmitting device of a device for detecting and locating the grounding point of a high-voltage line, which is an application example.

[0028] Figure 4 The figure is a schematic diagram of the structure of a receiving device of a high-voltage line grounding point detection and positioning device in an application example. DETAILED DESCRIPTION

[0029] The specific implementation of the high-voltage line grounding point detection and positioning device of the utility model is described in detail below with reference to the accompanying drawings.

[0030] See also Figure 1 As shown, Figure 1 The utility model is a schematic diagram of the structure of a device for detecting and locating the grounding point of a high-voltage line, which includes a transmitting device and a receiving device.

[0031] The transmitting device is connected to the circuit to be tested and the ground.

[0032] The receiving device is handheld or carried by a drone and moves under the line to be tested.

[0033] The above-mentioned high-voltage line grounding point detection and positioning device injects a specific high-frequency signal into the line to be tested through a transmitting device, and then detects and calculates the current and voltage signals of the line to be tested. By analyzing the voltage and current values ​​on the line to be tested, impedance calculation and threshold current comparison are performed, so as to accurately determine whether there is a grounding phenomenon in the line to be tested and preliminarily locate the connection point. The receiving device moves under the line to be tested to detect the high-frequency electromagnetic wave signal emitted by the line. If the line above the receiving device is short-circuited, the unchanged power value can be detected; if the detected power value is significantly reduced, it means that the line above the receiving device is not connected. Thereby, the accurate positioning of the grounding point can be achieved.

[0034] See also Figure 2 As shown, Figure 2 The figure is a schematic diagram of the structure of a device for detecting and locating a grounding point of a high-voltage line according to an embodiment.

[0035] In one of the embodiments, the transmitting device includes a power supply module, a signal source module, a DSP unit, an embedded ARM and an impedance ranging module.

[0036] The power module filters the 12V DC battery, uses a DC isolation power module to isolate the power supply, and uses Buck step-down and Boost step-up to power the DSP unit and signal source module respectively. A 12.6V rechargeable lithium-ion battery pack can be selected, equipped with an intelligent IC protection board to stabilize the output voltage and extend the battery life. At the same time, there is a power indicator to prevent low power use.

[0037] The signal source module can generate a three-phase AC signal according to the PWM signal generated by the DSP unit, and the power inversion is realized by the IPM chip. The PSS10S92E6AG can be selected to convert the DC signal into an AC signal, and then inject it into the transmission line after filtering. At the same time, the output signal is fed back to the DSP unit in real time for adjusting and controlling the PWM, thereby improving the accuracy of the signal source.

[0038] The DSP unit can generate a PWM signal to control the signal source module to generate a three-phase AC signal of a specific frequency, and realize the measurement and protection control of voltage and current signals. TMS320F2812 can be selected, which has a built-in ADC analog-to-digital converter.

[0039] The embedded ARM communicates with the DSP unit through a serial port, calculates the current and voltage signals measured by the impedance measurement module, analyzes the voltage and current values ​​on the circuit to be tested, calculates the impedance and compares the threshold current, determines whether there is a grounding phenomenon and preliminarily locates the connection location. An ARM920T chip can be selected and embedded in the Android operating system to make the detection device intelligent.

[0040] The impedance ranging module filters, amplifies and filters again the voltage and current signals injected into the circuit to be measured, and then sends them to the embedded ARM via the DSP unit. At the same time, it compares the signals with the transformer end to provide feedback control for the error. The amplifier can be LM339.

[0041] In one embodiment, the receiving device includes a power module, a DSP unit, an embedded ARM, a measurement module and a display module.

[0042] The power module filters the 12V DC battery, uses a DC isolation power module to isolate the power supply, and powers the DSP unit through Buck step-down. A 12.6V rechargeable lithium-ion battery pack can be selected, equipped with an intelligent IC protection board to stabilize the output voltage and extend the battery life. At the same time, there is a power indicator to prevent low power use.

[0043] The DSP unit receives the DC voltage value measured by the measuring module and performs serial communication with the embedded ARM. TMS320F2812 can be selected, which has a built-in ADC analog-to-digital converter.

[0044] The embedded ARM receives the DC voltage value measured by the module, obtains the power value of the electromagnetic wave emitted by the measured line, and accurately locates the grounding point by detecting the change of the power value. An ARM920T chip can be selected and embedded in the Android operating system to make the detection device intelligent.

[0045] The measuring module converts the power value of the electromagnetic wave emitted by the circuit to be tested into a DC voltage value corresponding thereto. The power detection using this method can be unaffected by the waveform of the electromagnetic wave signal. The measuring module is composed of a tuned filter, a power divider, an attenuation module, an amplification module, a radio frequency switch, a detection circuit and a voltage follower. After the signal to be tested is filtered by the tuned filter, it is divided into three paths by the power divider: one path remains unchanged, one path is weakened by the attenuation module, and one path is enhanced by the amplification module. The radio frequency switch can select a suitable signal to output to the detection module to keep the output of the detection circuit moderate. The detection circuit converts the power value into a DC voltage value corresponding thereto. The voltage follower can reduce the influence of the subsequent circuit on the previous circuit, making the measurement more accurate. The tuned filter can be ADMV8052, the power divider can be 03KPD-2^300M-3S, the attenuation module can be PE402 programmable attenuator, the amplification module can be ADL5243 programmable gain RF amplifier, the RF switch can be RF1604 four-throw switch, the detection circuit can be AD8361 true RMS detection chip, and the voltage follower can be LM324.

[0046] The display module can display the geographical location information of the grounding point. The input voltage required for the liquid crystal display LCD is 3.3v, which can be directly connected to the embedded ARM. The input signal is a UART interface, and an HDMI 7-inch high-definition capacitive touch screen can be selected. In addition to the required power supply and ground wire, only two signal wires are required, the signal is more stable, and the design is more reliable and reasonable.

[0047] In one embodiment, the accuracy and speed of the ADC digital-to-analog converter of the DSP unit are very high, but filtering is also required before the signal is input. A second-order bandpass filter composed of an amplifier can be selected.

[0048] In order to more clearly describe the detection and positioning device for the grounding point of a high-voltage line of the present invention, a preferred embodiment is described below.

[0049] common Figure 3 As shown, Figure 3 The figure is a schematic diagram of the structure of a transmitting device of a device for detecting and locating the grounding point of a high-voltage line, which is an application example.

[0050] Battery 01 is a 12V battery. You can choose a 12.6V rechargeable lithium-ion battery pack, equipped with an intelligent IC protection board to stabilize the output voltage and extend the battery life. At the same time, there is a power indicator light to prevent low power use.

[0051] Buck circuit 02 and Boost circuit 03 provide 5V and 15V power supplies to DSP unit 05 and IPM chip 06 respectively.

[0052] The embedded ARM 04 plays the role of overall control. ARM integrates embedded control, efficient data acquisition and network communication. The core calculation speed is very fast and can provide a friendly human-computer operation interface. The ARM920T chip can be selected and embedded in the Android operating system to make the detection device intelligent.

[0053] DSP unit 05 is the core unit of control, algorithm and signal processing. It usually adopts Harvard pipeline architecture and is equipped with special hardware multipliers. It is required to be able to process the sampled signals and perform software filtering and fast Fourier decomposition on the signals. TMS320F2812 can be selected, which has built-in ADC analog-to-digital converter and PWM wave control module, and can generate PWM wave to control IPM chip 06 to generate three-phase AC signal.

[0054] IPM chip 06 is a chip composed of high-speed and low-power switch tubes, optimized gate-level drive circuits and fast protection circuits. It has integrated fault detection circuits such as overvoltage, overcurrent and overheating. Compared with conventional inverter bridge AC signal sources, this signal source does not need to design PWM drive circuits, AC inverter bridges and protection circuits. The combination of IPM chip 06 and DSP unit 05 simplifies the logic circuit, reduces power consumption, and improves the accuracy and reliability of the circuit. PSS10S92E6AG can be used. The three-phase AC signal generated by it is filtered by filter 07 and transmitted to the primary circuit of isolation transformer 08.

[0055] The isolation transformer 08 boosts the three-phase AC signal to increase the power supplied to the circuit to be tested, and the high voltage is connected to the circuit to be tested. A leakage transformer with a 2x relationship can be selected.

[0056] The three-phase AC signal is filtered through the filter 09, and the amplifier 10 reduces the voltage signal so that it is within the range of the digital-to-analog converter of the DSP unit 05. After being processed by the filter 11, it is sent to the DSP unit 05 for sampling and calculation, thereby forming a feedback loop, making the AC signal output to the circuit to be tested more reliable.

[0057] The current signal on the circuit to be measured obtained by the current transformer 12 is amplified by the amplifier 13, and its accuracy is improved, which can better adapt to the measurement range of the DSP unit 05. The voltage signal on the circuit to be measured needs to be reduced by the amplifier 14 before it can be input into the DSP unit 05. The amplifier can be LM339.

[0058] By analyzing the voltage and current values ​​on the line to be tested, calculating the impedance and comparing the threshold current, it is possible to determine whether the line is grounded and to preliminarily locate the connection point.

[0059] common Figure 4 As shown, Figure 4 The figure is a schematic diagram of the structure of a receiving device of a high-voltage line grounding point detection and positioning device in an application example.

[0060] Battery 01 is a 12V battery. You can choose a 12.6V rechargeable lithium-ion battery pack, equipped with an intelligent IC protection board to stabilize the output voltage and extend the battery life. At the same time, there is a power indicator to prevent low power. Buck step-down circuit 02 provides 5V power supply for DSP unit 04.

[0061] The embedded ARM 03 plays the role of overall control. ARM integrates embedded control, efficient data acquisition and network communication. The core calculation speed is very fast and can provide a friendly human-machine operation interface. The ARM920T chip can be selected and embedded in the Android operating system to make the detection device intelligent.

[0062] DSP unit 04 is the core unit of control, algorithm and signal processing. It usually adopts Harvard pipeline architecture and is equipped with a special hardware multiplier. It is required to be able to process the sampled signal and perform software filtering and fast Fourier decomposition on the signal. TMS320F2812 can be selected, which has a built-in ADC analog-to-digital converter.

[0063] Tuned filter 05 has strong frequency selectivity and narrowband filtering characteristics, and can select the signal of a specific frequency emitted by the circuit to be tested from the electromagnetic wave signal received by the antenna. ADMV8052 can be selected, which has a digitally selectable operating frequency and integrates three bandpass filters, spanning three specified frequency bands from 30MHZ to 520MHZ.

[0064] The power divider 06 divides the signal energy into three paths. Through the automatic switching of channels, the voltage output by the detection circuit 10 is not too large or too small, and the voltage is placed in the best linear region of the detection chip, so as to obtain the best measurement effect. You can choose 03KPD-2^300M-3S, whose working range frequency can reach 2MHZ~300MHZ.

[0065] The amplifier module 07 can use the ADL5243 programmable gain RF amplifier, and the attenuation module 08 can use the PE402 programmable attenuator. Through SPI control, the amplification and attenuation can be up to 31.5dB in 0.5dB steps.

[0066] The RF switch 09 can be a RF1604 four-throw switch, and the signal can be selected to be output to the detection circuit 10. The attenuation channel is selected by default to prevent the input of a high-power signal from causing the output voltage of the detection circuit 10 to be too large, thereby protecting the hardware. Then, the appropriate channel is selected according to the current output voltage until the output voltage is reasonable and moderate.

[0067] The detection circuit 10 can select the AD8361 true RMS detection chip and use a transformer for coupling, so that the input impedance is 50Ω, the operating frequency is 50Hz~2.7GHz, the input power range is greater than 60dB, and the signal power can be converted into a DC voltage output. For every 1dBm increase in power, the voltage increases by 50mV, and the output result is independent of the signal waveform and modulation.

[0068] The voltage follower 11 may be LM324, which has the characteristics of high input impedance and low output impedance, and can reduce the influence of the subsequent circuit on the previous circuit, making the measurement more accurate.

[0069] The display module 12 needs to meet the conditions of stable control, few signal lines, HDMI interface, and touch control. An HDMI 7-inch high-definition capacitive touch screen can be selected. The touch screen only needs to be connected to the embedded ARM 03 through a USB cable and an HDMI cable. There is no screen burn-in phenomenon, and the service life is longer. It can clearly display the operation interface of the device, display the grounding point status and geographical location information in real time, and has sensitive touch, which is convenient for human-computer friendly interaction.

[0070] The receiving device is moved under the circuit to be tested to detect the high-frequency electromagnetic wave signal emitted by the circuit. If the circuit above the receiving device is short-circuited, the power value that remains unchanged can be detected; if the detected power value is significantly reduced, it means that the circuit above the receiving device is not connected. This can achieve accurate positioning of the grounding point.

[0071] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A device for detecting and locating a high-voltage line grounding point, characterized in that: It includes a transmitting device and a receiving device; The transmitting device is connected to the circuit to be tested and the ground; The receiving device is handheld or carried by a drone and moves under the line to be tested; The transmitting device includes a power supply module, a signal source module, a DSP unit, an embedded ARM and an impedance ranging module; The receiving device includes a power module, a DSP unit, an embedded ARM, a measurement module and a display module; The power module filters the 12V DC battery, uses a DC isolation power module to isolate the power supply, and uses Buck step-down and Boost step-up to power the DSP unit and signal source module respectively; The signal source module can generate a three-phase AC signal based on the PWM signal generated by the DSP unit, and inject it into the circuit to be tested after LC filtering. At the same time, the output signal is fed back to the DSP in real time for adjusting and controlling PWM, thereby improving the accuracy of the signal source; The impedance ranging module filters, amplifies and re-filters the voltage and current signals injected into the line to be tested, and then sends them to the embedded ARM through the DSP unit. At the same time, it compares them with the signals at the transformer end to provide feedback control for the errors. The measurement module is composed of a tuned filter, a power divider, an attenuation module, an amplification module, a radio frequency switch, a detection circuit and a voltage follower. After being filtered by the tuned filter, the measured signal is divided into three paths by the power divider: one path remains unchanged, one path is weakened by the attenuation module, and one path is enhanced by the amplification module. The radio frequency switch can select a suitable signal to output to the detection module to keep the output of the detection circuit moderate. The detection circuit converts the power value into a corresponding DC voltage value. The voltage follower can reduce the influence of the subsequent circuit on the previous circuit, making the measurement more accurate. The display module is directly connected to the embedded ARM and can display the geographical location information of the grounding point.

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