Grounding lightning protection testing device for high-voltage electric tower

Abstract

A high-voltage electric tower grounding lightning protection test device comprises a transmitter, a receiver and a GNSS positioning base station. Wherein the transmitter is used for applying an electromagnetic signal with a specific frequency to an underground buried line, and the underground buried line generates a secondary induction electromagnetic field; the receiver is used together with the matched transmitter and is used for receiving the electromagnetic signal with the specific frequency, which is generated by the transmitter through the underground buried line, and analyzing and calculating the electromagnetic signal to obtain the position and the buried depth of the underground pipeline; and the GNSS positioning base station is used for receiving satellite positioning information at a fixed position and transmitting own position information to the mobile station on the receiver, so that the mobile station calculates high-precision position information of the mobile station according to the own position information and the position information of the positioning base station. According to the invention, the grounding resistance of the high-voltage electric tower is accurately measured and monitored in real time, and the lightning protection capability of a power system can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of electric power engineering, and in particular to a grounding lightning protection test device for a high-voltage electric tower. Background Art

[0002] As an important part of the power transmission system, high-voltage towers must have a good grounding system and lightning protection to ensure the safety and stability of the power system. In the grounding system of the tower, the grounding resistance value is an important indicator to measure its grounding performance. At the same time, the lightning protection system needs to be effectively tested and maintained to ensure that no damage to power equipment occurs during lightning weather. During the operation of overhead transmission lines, lightning accidents caused by poor grounding of towers account for a high proportion of line failure rates. This is mainly because when lightning strikes the top of the pole or the ground wire, the lightning current flows into the ground through the tower grounding device, and due to the high grounding resistance, a higher counter-voltage is generated. Therefore, accurate measurement and real-time monitoring of the grounding resistance of high-voltage towers are of great significance to improving the lightning protection capability of the power system. Summary of the invention

[0003] In view of the above problems, the present invention is proposed to provide a high-voltage tower grounding lightning protection test device that overcomes the above problems or at least partially solves the above problems.

[0004] In order to solve the above technical problems, the embodiments of the present application disclose the following technical solutions:

[0005] The embodiment of the present invention discloses a high-voltage tower grounding lightning protection test device, comprising: a transmitter, a receiver and a GNSS positioning base station; wherein:

[0006] A transmitter is used to add an electromagnetic signal of a specific frequency to the underground buried wire, so that the underground buried wire generates a secondary induced electromagnetic field;

[0007] A receiver is used to receive an electromagnetic signal of a specific frequency generated by a transmitter through an underground buried line, and obtain the location and burial depth of the underground pipeline by analyzing and calculating the electromagnetic signal;

[0008] The GNSS positioning base station is used to receive satellite positioning information at a fixed location and transmit its own location information to the mobile station located on the receiver, allowing the mobile station to calculate the high-precision location information of the mobile station based on its own location information and the location information of the positioning base station.

[0009] Furthermore, the transmitter includes an eddy current signal control unit, a ground resistance test unit and a single chip unit; wherein:

[0010] The eddy current signal control unit includes a high-power DCDC switching power supply control circuit, a full-bridge differential control circuit and an eddy current signal acquisition circuit; the high-power DCDC switching power supply control circuit is used to control the rated voltage and current output by the high-power DCDC switching power supply, and the full-bridge differential control circuit is used to convert the DC signal into a square wave differential signal of a specific frequency and output it; the eddy current signal acquisition circuit is used to collect the output voltage, current, resistance and display them;

[0011] The ground resistance test unit includes a signal generator and a measuring subunit. The signal generator is used to generate an output measurement signal source and provide a current signal of a specific frequency and amplitude. The measuring subunit is used to obtain a tiny signal from the electrode and send it to a receiver after processing.

[0012] Furthermore, the receiver includes an analog signal board, a digital signal board and a main control board; wherein:

[0013] The analog signal board is used to perform analog processing on the signal sent by the transmitter and send the analog processed signal to the digital signal board;

[0014] The digital signal board is used to process the analog processed signal into a digital signal and upload the digital processed signal to the receiver main control board through the serial port;

[0015] The main control board is used for communicating with the serial color screen and displaying the switching of text, numerical values ​​and icons. It is also used to communicate with the GNSS module, obtain the location information sent by the GNSS positioning base station, process the location information, combine the location information with the buried depth of the grounding device, and store the combined location information. It is also used to communicate with the digital board, process the parameters uploaded by the digital board, obtain the buried depth and orientation, and display them on the color screen.

[0016] Furthermore, the analog signal board is used to perform analog processing on the signal sent by the transmitter, including signal amplification and filtering processing on the signal, and synchronously collecting the processed signal; the specific method includes:

[0017] Amplify the signal, determine the amplifier type based on the signal's amplitude range, frequency range, and power consumption requirements, input the signal received by the antenna into the amplifier, and through the amplifier's gain effect, increase the signal strength to a range that can be recognized by subsequent processing circuits;

[0018] Filter the signal, determine the filtering type according to the signal frequency range to be retained or removed, and the filtering type includes at least low-pass filtering, high-pass filtering, band-pass filtering and band-stop filtering; set the cutoff frequency, bandwidth and roll-off characteristics of the filter, input the signal output by the amplifier into the filter, remove unnecessary frequency components through the filtering action of the filter, and obtain a pure target signal;

[0019] Acquire the signal synchronously, determine the acquisition card type according to the number of acquisition channels, sampling rate, and resolution requirements, input the signal output by the filter into the analog input channel of the synchronous acquisition card, determine the sampling frequency and sampling period according to the highest frequency of the signal and the sampling theorem, start the data acquisition function of the synchronous acquisition card, synchronously acquire the processed signal, and process and analyze the acquired data.

[0020] Furthermore, the digital signal board is used to perform digital signal processing on the analog processed signal, and the specific method includes:

[0021] Preprocess the analog processed signal, and perform ADC data acquisition on the preprocessed signal;

[0022] Perform digital signal processing on the data collected by ADC according to preset rules;

[0023] The strength of the coil induced magnetic field is obtained through digital signal processing, and the pipeline positioning and depth algorithm calculation are performed based on the strength of the magnetic field.

[0024] Further, the analog processed signal is preprocessed, including amplifying the analog processed signal, and the specific method includes:

[0025] Configure the parameters of the digital programmable instrumentation amplifier, determine the gain value of the digital programmable instrumentation amplifier according to the amplitude of the input signal and the output requirements, and write the gain value to the gain register of the amplifier through the I2C or SPI interface; determine the bandwidth of the amplifier according to the signal frequency, and write the bandwidth value to the bandwidth register through the digital interface;

[0026] The signal to be amplified is amplified and input into the amplifier through the IN+ and IN- pins. The amplifier amplifies the input signal according to the configured gain value and the amplified signal is output to the subsequent circuit through the OUT pin.

[0027] Furthermore, ADC data acquisition is performed on the preprocessed signal, and the specific method includes:

[0028] Configure ADC parameters. According to actual needs, determine the sampling rate and number of channels of the ADC. The sampling rate should be at least twice the maximum frequency of the input signal. Determine the sampling bit number and number of sampling points of the ADC.

[0029] The sampling is performed using an 8-fold sampling multiple and DMA is used to transfer the data to a defined array. The array size is M*N, where M is the number of channels and N is the number of sampling points. The array storage order is 1-M repeated storage. Each sampling is triggered by the TIM1 timer. When the number of samples reaches M*N, the A defined array is split into arrays of 8 signals. The data can be processed by configuring a DMA full interrupt.

[0030] Furthermore, the data after ADC data acquisition is subjected to digital signal processing according to a preset rule, wherein the preset rule is Fourier transform processing; for a periodic function, its Fourier series representation is defined as:

[0031]

[0032] Where T is the period of the function, Fn is the Fourier expansion coefficient, and Fn is:

[0033]

[0034] For real-valued functions, their Rieger series can be written as:

[0035]

[0036] where a n and b n It is the amplitude of the real frequency component. A periodic signal is composed of an infinite number of sine and cosine waves. When the amplitude of the signal is to be obtained, the signal is transformed by Fourier transform to obtain the amplitude of the corresponding frequency.

[0037] Furthermore, when the ADC sampling frequency is Fs, the sampling signal frequency is f, and the number of sampling points is N, the sampling signal resolution is Fs / N, then the frequency of the signal to be sampled is the Fs / N+fth point of the Fourier transform, the first point is the DC component, and the amplitude K obtained by the Fourier transform is converted to the DC component amplitude of the signal LDC=K / N, and the AC component amplitude LAC=K / (N / 2).

[0038] Furthermore, when the ADC sampling frequency is Fs, the number of sampling points is N, and the transmitter transmission signal is P, the sampling signal resolution is Fs / N. At this time, the maximum modulus value obtained by the Fourier transform is the sampling point position P / (Fs / N) when the transmission signal is P, that is, the P / (Fs / N)+1th value is the maximum value of the Fourier transform.

[0039] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0040] The present invention discloses a grounding lightning protection test device for a high-voltage electric tower, comprising: a transmitter, a receiver and a GNSS positioning base station; wherein: the transmitter is used to add a specific frequency electromagnetic signal to an underground buried line, and the underground buried line generates a secondary induced electromagnetic field; the receiver is used together with a matching transmitter to receive the specific frequency electromagnetic signal generated by the transmitter through the underground buried line, and the position and burial depth of the underground pipeline are obtained by analyzing and calculating the electromagnetic signal; the GNSS positioning base station is used to receive satellite positioning information at a fixed position, and transmit its own position information to a mobile station located on the receiver, so that the mobile station can calculate the high-precision position information of the mobile station according to its own position information and the position information of the positioning base station. The present invention can accurately measure and monitor the grounding resistance of the high-voltage electric tower in real time, and can improve the lightning protection capability of the power system.

[0041] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0043] Figure 1 This is a structural diagram of a high-voltage tower grounding lightning protection test device in Example 1 of the present invention;

[0044] Figure 2 This is a schematic diagram of simulation of the position of the mode value sampling points obtained by Fourier transform in Embodiment 1 of the present invention;

[0045] Figure 3 This is a table of the locations of the module value sampling points obtained by Fourier transformation in Embodiment 1 of the present invention. DETAILED DESCRIPTION

[0046] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0047] In order to solve the problems existing in the prior art, an embodiment of the present invention provides a high-voltage tower grounding lightning protection test device.

[0048] Example 1

[0049] The present invention discloses a high voltage tower grounding lightning protection test device. Figure 1, including: a transmitter, a receiver and a GNSS positioning base station; wherein:

[0050] A transmitter is used to add an electromagnetic signal of a specific frequency to the underground buried wire, so that the underground buried wire generates a secondary induced electromagnetic field;

[0051] In this embodiment, the transmitter includes an eddy current signal control unit, a ground resistance test unit and a single-chip computer unit; wherein: the eddy current signal control unit includes a high-power DCDC switching power supply control circuit, a full-bridge differential control circuit and an eddy current signal acquisition circuit; the high-power DCDC switching power supply control circuit is used to control the rated voltage and current output of the high-power DCDC switching power supply, and the full-bridge differential control circuit is used to convert the DC signal into a square wave differential signal of a specific frequency and output it; the eddy current signal acquisition circuit is used to collect the output voltage, current, resistance and display them;

[0052] Specifically, the switching power supply module used in this embodiment is a 600W, voltage and current adjustable, constant voltage and constant current high-power switching power supply module - KUB4836EB-10A-RS. The power supply module inputs 24V voltage, can output 3V~60V voltage, 0.1A~10A current, and is controlled by analog quantity. The module also has a switch pin that can control the switch of the power supply module. The power supply module is a 1 / 4 brick plug-in package, and the top is designed with a fixed heat sink.

[0053] The full-bridge differential control circuit uses four low-resistance high-power MOS tubes NCEP02T10D and a full-bridge driver chip IR2113S, of which IR2113S is isolated from the microcontroller by 74H132D. The main function of this circuit is to control IR2113S through the differential PWM waveform output by the microcontroller, so that the four MOS tubes switch regularly and convert the DC output of the high-power DCDC module into a differential PWM waveform output.

[0054] The eddy current signal acquisition circuit collects the current flowing through four 200mΩ high-power chip resistors, and then collects the voltage output by the high-power DCDC switching power supply module to obtain the resistance value of the eddy current signal, thereby completing the collection of eddy current signal related information. The current adjustment gear is set based on the eddy current, and the size of the eddy current is controlled by the program to change the output power.

[0055] The ground resistance test unit includes a signal generator and a measuring subunit. The signal generator is used to generate an output measurement signal source and provide a current signal of a specific frequency and amplitude. The measuring subunit is used to obtain a tiny signal from the electrode and send it to a receiver after processing.

[0056] The signal generator mainly uses the DDS signal generator chip AD9833 from ADI. This chip is a high-performance, low-power programmable waveform generator suitable for applications that require precise frequency, phase, and waveform control. Its working principle is based on digital frequency synthesis (DFS) technology, which controls the internal digital registers to accurately adjust the frequency and phase of the output signal. By sending control commands to AD9833 through the SPI interface, users can select the required waveform, set the frequency value, and adjust the phase. The DAC conversion module inside the AD9833 converts these digital signals into analog waveforms, thereby outputting the required signals.

[0057] In order to improve the accuracy of ground resistance measurement, the amplitude of the signal must be increased. Therefore, the AD8605 operational amplifier chip of ADI is used to build an amplifier circuit to amplify the weak signal source output by the DDS chip to 24V before output. An LC filter is connected in series at the signal input end to filter out the clutter generated by spatial interference, improve the waveform output accuracy, and prevent the amplifier from amplifying the clutter.

[0058] The measurement subunit consists of two parts: the differential signal amplifier circuit and the ADC acquisition circuit. The differential signal amplifier circuit is mainly used to convert the collected differential sine wave signal into a single-ended sine wave signal and amplify it; the ADC acquisition circuit is mainly used to convert the analog sine wave signal into a digital signal and transmit it to the microcontroller through SPI communication. At the same time, the microcontroller controls the range and sampling frequency of the ADC chip through the IO port, and reads the alarm status of the ADC chip. The differential signal amplifier circuit mainly selects the differential to single-ended operational amplifier AD620 of ADI. This operational amplifier is an operational amplifier with high precision, low power consumption, high gain stability, wide input voltage range, and low noise performance. It is widely used in signal amplification, measurement, sensor interface and other fields. The amplifier can select the amplification factor through a resistor value.

[0059] A receiver is used to receive an electromagnetic signal of a specific frequency generated by a transmitter through an underground buried line, and obtain the location and burial depth of the underground pipeline by analyzing and calculating the electromagnetic signal;

[0060] In this embodiment, the receiver includes an analog signal board, a digital signal board and a main control board; wherein: the analog signal board is used to perform analog processing on the signal sent by the transmitter, and send the signal after the analog processing to the digital signal board; the digital signal board is used to perform digital signal processing on the signal after analog processing, and upload the digitally processed signal to the main control board of the receiver through the serial port; the main control board is used for communicating with the serial port color screen, displaying the switching of text, numerical values ​​and icons; it is also used to communicate with the GNSS module, obtain the location information sent by the GNSS positioning base station, process the location information, combine the location information with the buried depth of the grounding device, and store the combined location information; it is also used to communicate with the digital board, process the parameters uploaded by the digital board, obtain the buried depth and azimuth, and display them on the color screen.

[0061] In some preferred embodiments, the analog signal board is used to perform analog processing on the signal sent by the transmitter, including amplifying and filtering the signal, and synchronously collecting the processed signal; the specific method includes:

[0062] Amplify the signal, determine the amplifier type based on the signal's amplitude range, frequency range, and power consumption requirements, input the signal received by the antenna into the amplifier, and through the amplifier's gain effect, increase the signal strength to a range that can be recognized by subsequent processing circuits;

[0063] Filter the signal, determine the filtering type according to the signal frequency range to be retained or removed, and the filtering type includes at least low-pass filtering, high-pass filtering, band-pass filtering and band-stop filtering; set the cutoff frequency, bandwidth and roll-off characteristics of the filter, input the signal output by the amplifier into the filter, remove unnecessary frequency components through the filtering action of the filter, and obtain a pure target signal;

[0064] Acquire the signal synchronously, determine the acquisition card type according to the number of acquisition channels, sampling rate, and resolution requirements, input the signal output by the filter into the analog input channel of the synchronous acquisition card, determine the sampling frequency and sampling period according to the highest frequency of the signal and the sampling theorem, start the data acquisition function of the synchronous acquisition card, synchronously acquire the processed signal, and process and analyze the acquired data.

[0065] In some preferred embodiments, the digital signal board is used to perform digital signal processing on the analog processed signal, and the specific method includes:

[0066] Preprocess the analog processed signal, and perform ADC data acquisition on the preprocessed signal;

[0067] Perform digital signal processing on the data collected by ADC according to preset rules;

[0068] The strength of the coil induced magnetic field is obtained through digital signal processing, and the pipeline positioning and depth algorithm calculation are performed based on the strength of the magnetic field.

[0069] In some preferred embodiments, the analog processed signal is preprocessed, including amplifying the analog processed signal, and the specific method includes:

[0070] Configure the parameters of the digital programmable instrumentation amplifier, determine the gain value of the digital programmable instrumentation amplifier according to the amplitude of the input signal and the output requirements, and write the gain value to the gain register of the amplifier through the I2C or SPI interface; determine the bandwidth of the amplifier according to the signal frequency, and write the bandwidth value to the bandwidth register through the digital interface;

[0071] The signal to be amplified is amplified and input into the amplifier through the IN+ and IN- pins. The amplifier amplifies the input signal according to the configured gain value and the amplified signal is output to the subsequent circuit through the OUT pin.

[0072] In some preferred embodiments, ADC data acquisition is performed on the preprocessed signal, and the specific method includes: configuring ADC parameters, determining the sampling rate and number of channels of the ADC according to actual needs, and the sampling rate should be at least twice the maximum frequency of the input signal; determining the sampling bit number and the number of sampling points of the ADC;

[0073] The sampling is performed using an 8-fold sampling multiple and DMA is used to transfer the data to a defined array. The array size is M*N, where M is the number of channels and N is the number of sampling points. The array storage order is 1-M repeated storage. Each sampling is triggered by the TIM1 timer. When the number of samples reaches M*N, the A defined array is split into arrays of 8 signals. The data can be processed by configuring a DMA full interrupt.

[0074] Specifically, assume that the ADC sampling chip has three 12-bit ADCs, each with a sampling rate of 2.4MSPS, and the three chips are turned on to collect data at a total sampling rate of 7.2MSPS. Since the maximum frequency of the transmitter is 30K, according to the Nyquist sampling theorem, the sampling rate must be more than twice the sampling frequency to restore the signal. The system uses a 2^N sampling multiple for sampling, and the number of sampling points is 1024. When the number of sampling points reaches 1024, FFT transformation is performed to obtain the required value. When N=3, the sampling rate is 8 times, so the single ADC sampling is 240KSPS multiplied by 8 signals, a total of 1.92MSPS, which is less than 2.4MSPS and meets the requirements. Assume that there are 8 sampling channels, the sampling bit number is 12 bits, and the channels are ADC_Channel_1~ADC_Channel_8. DMA is used to transfer them to the defined array ADCConvertedValue[8*1024], and the array size is 8*1024. The storage order is 1-8 repeated storage. Each sampling is triggered by the TIM1 timer. When the number of samples reaches 8*1024, ADCConvertedValue[8*1024] is split into eight signal arrays ADCConvertedValue1_in

[1024] ~ADCConvertedValue8_in

[1024] . The data can be processed by configuring the DMA full interrupt.

[0075] In some preferred embodiments, the data after ADC data acquisition is subjected to digital signal processing according to a preset rule, and the preset rule is Fourier transform processing; Fourier transform is a method of analyzing a signal, which can analyze the components of a signal and can also synthesize a signal with these components. Many waveforms can be used as components of a signal, such as a sine wave, a square wave, a sawtooth wave, etc., and Fourier transform uses a sine wave as a component of a signal.

[0076] The continuous form of the Fourier transform is actually a generalization of the Fourier series, because the integral is actually a summation operator in the limit form; for periodic functions, the Fourier series representation is defined as:

[0077]

[0078] Where T is the period of the function, Fn is the Fourier expansion coefficient, and Fn is:

[0079]

[0080] For real-valued functions, their Rieger series can be written as:

[0081]

[0082] where a nand bn are the amplitudes of the real frequency components. A periodic signal is composed of an infinite number of sine and cosine waves. When the amplitude of the signal is to be obtained, the signal is transformed through Fourier transform to obtain the amplitude of the corresponding frequency.

[0083] In this embodiment, when the ADC sampling frequency is Fs, the sampling signal frequency is f, and the number of sampling points is N, the sampling signal resolution is Fs / N, then the frequency of the signal to be sampled is the Fs / N+fth point of Fourier transform, the first point is the DC component, the amplitude K obtained by Fourier transform, converted to the DC component amplitude of the signal LDC=K / N, and the AC component amplitude LAC=K / (N / 2). For example, Fs=1024HZ, N=1024, f=256HZ, and its resolution is 1024HZ / 1024=1HZ. The resolution increases with the increase of the number of sampling points. Since the resolution is 1HZ, f is the 257th point of Fourier transform, the first point is the DC component, and the amplitude K obtained by Fourier transform, converted to the signal amplitude formula is: DC component amplitude=K / N, AC component amplitude=K / (N / 2).

[0084] In this embodiment, when the ADC sampling frequency is Fs, the number of sampling points is N, and the transmitter transmits a signal of P, the obtained sampling signal resolution is Fs / N. At this time, the maximum modulus value obtained by Fourier transform is the sampling point position P / (Fs / N) where the transmit signal is P, that is, the P / (Fs / N)+1th value is the maximum value of Fourier transform. For example, the sampling frequency is 240K, the number of sampling points is 1024, and the resolution is 240KHZ / 1024=234.375HZ. When the transmitter transmits a signal of 30K, the maximum modulus value obtained by FFT transform is the position where 30K is located, that is, 30KHZ / 234.375=128, that is, the 129th value is the maximum value.

[0085] The maximum value point is simulated in MATLAB through the STM32F4 library function, and the Figure 2 Signal output, view the maximum M value through MATLAB workplace as follows Figure 3 As shown, we can see that the value of the 129th point is 3.0732*10^5, which is the location of the 30K frequency, which is similar to the theoretical result. The value 3.0732*10^5 / (N / 2)=600.234 is converted to mv, which is the voltage value induced by the coil. The oscilloscope is placed on the front end of the ADC sampling and the filtering function is turned on. The peak-to-peak value is 590mv, which is similar to the result obtained by digital signal processing. It can be seen that the digital signal processing is correct.

[0086] The GNSS positioning base station is used to receive satellite positioning information at a fixed position, and transmit its own position information to a mobile station located on the receiver, so that the mobile station can calculate the high-precision position information of the mobile station based on its own position information and the position information of the positioning base station. Among them, the GNSS positioning base station receives satellite positioning information, and transmits its own position information to the mobile station located on the receiver, so that the mobile station can calculate the high-precision position information of the mobile station based on its own position information and the position information of the positioning base station. This is a conventional technical means in the field, and this embodiment will not be repeated here.

[0087] This embodiment discloses a high-voltage tower grounding lightning protection test device, including: a transmitter, a receiver and a GNSS positioning base station; wherein: the transmitter is used to add a specific frequency electromagnetic signal to an underground buried line, and the underground buried line generates a secondary induced electromagnetic field; the receiver is used together with the matching transmitter to receive the specific frequency electromagnetic signal generated by the transmitter through the underground buried line, and the position and burial depth of the underground pipeline are obtained by analyzing and calculating the electromagnetic signal; the GNSS positioning base station is used to receive satellite positioning information at a fixed position, and transmit its own position information to a mobile station located on the receiver, so that the mobile station can calculate the high-precision position information of the mobile station according to its own position information and the position information of the positioning base station. The present invention can accurately measure and monitor the grounding resistance of the high-voltage tower in real time, and can improve the lightning protection capability of the power system.

[0088] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0089] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0090] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0091] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0092] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0093] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A high voltage tower grounding lightning protection test device, characterized in that: include: Transmitter, receiver and GNSS positioning base station; including: A transmitter is used to add an electromagnetic signal of a specific frequency to the underground buried wire, so that the underground buried wire generates a secondary induced electromagnetic field; A receiver is used to receive an electromagnetic signal of a specific frequency generated by a transmitter through an underground buried line, and obtain the location and burial depth of the underground pipeline by analyzing and calculating the electromagnetic signal; The GNSS positioning base station is used to receive satellite positioning information at a fixed location and transmit its own location information to the mobile station located on the receiver, allowing the mobile station to calculate the high-precision location information of the mobile station based on its own location information and the location information of the positioning base station.

2. A high-voltage tower grounding lightning protection test device as claimed in claim 1, characterized in that: The transmitter includes an eddy current signal control unit, a ground resistance test unit and a single chip unit; wherein: The eddy current signal control unit includes a high-power DCDC switching power supply control circuit, a full-bridge differential control circuit and an eddy current signal acquisition circuit; the high-power DCDC switching power supply control circuit is used to control the rated voltage and current output by the high-power DCDC switching power supply, and the full-bridge differential control circuit is used to convert the DC signal into a square wave differential signal of a specific frequency and output it; the eddy current signal acquisition circuit is used to collect the output voltage, current, resistance and display them; The ground resistance test unit includes a signal generator and a measuring subunit. The signal generator is used to generate an output measurement signal source and provide a current signal of a specific frequency and amplitude. The measuring subunit is used to obtain a tiny signal from the electrode and send it to a receiver after processing.

3. A high-voltage tower grounding lightning protection test device as claimed in claim 1, characterized in that: The receiver includes an analog signal board, a digital signal board and a main control board; wherein: The analog signal board is used to perform analog processing on the signal sent by the transmitter and send the analog processed signal to the digital signal board; The digital signal board is used to process the analog processed signal into a digital signal and upload the digital processed signal to the receiver main control board through the serial port; The main control board is used for communicating with the serial color screen and displaying the switching of text, numerical values ​​and icons. It is also used to communicate with the GNSS module, obtain the location information sent by the GNSS positioning base station, process the location information, combine the location information with the buried depth of the grounding device, and store the combined location information. It is also used to communicate with the digital board, process the parameters uploaded by the digital board, obtain the buried depth and orientation, and display them on the color screen.

4. A high-voltage tower grounding lightning protection test device as claimed in claim 3, characterized in that: The analog signal board is used to perform analog processing on the signal sent by the transmitter, including signal amplification and filtering, and synchronous acquisition of the processed signal; the specific methods include: Amplify the signal, determine the amplifier type based on the signal's amplitude range, frequency range, and power consumption requirements, input the signal received by the antenna into the amplifier, and through the amplifier's gain effect, increase the signal strength to a range that can be recognized by subsequent processing circuits; Filter the signal, determine the filtering type according to the signal frequency range to be retained or removed, and the filtering type includes at least low-pass filtering, high-pass filtering, band-pass filtering and band-stop filtering; set the cutoff frequency, bandwidth and roll-off characteristics of the filter, input the signal output by the amplifier into the filter, remove unnecessary frequency components through the filtering action of the filter, and obtain a pure target signal; Acquire the signal synchronously, determine the acquisition card type according to the number of acquisition channels, sampling rate, and resolution requirements, input the signal output by the filter into the analog input channel of the synchronous acquisition card, determine the sampling frequency and sampling period according to the highest frequency of the signal and the sampling theorem, start the data acquisition function of the synchronous acquisition card, synchronously acquire the processed signal, and process and analyze the acquired data.

5. A high-voltage tower grounding lightning protection test device as claimed in claim 3, characterized in that: The digital signal board is used to process the analog processed signal into a digital signal. The specific methods include: Preprocess the analog processed signal, and perform ADC data acquisition on the preprocessed signal; Perform digital signal processing on the data collected by ADC according to preset rules; The strength of the coil induced magnetic field is obtained through digital signal processing, and the pipeline positioning and depth algorithm calculation are performed based on the strength of the magnetic field.

6. A high-voltage tower grounding lightning protection test device as claimed in claim 5, characterized in that: Preprocessing the analog processed signal includes amplifying the analog processed signal. The specific method includes: Configure the parameters of the digital programmable instrumentation amplifier, determine the gain value of the digital programmable instrumentation amplifier according to the amplitude of the input signal and the output requirements, and write the gain value to the gain register of the amplifier through the I2C or SPI interface; determine the bandwidth of the amplifier according to the signal frequency, and write the bandwidth value to the bandwidth register through the digital interface; The signal to be amplified is amplified and input into the amplifier through the IN+ and IN- pins. The amplifier amplifies the input signal according to the configured gain value and the amplified signal is output to the subsequent circuit through the OUT pin.

7. A high-voltage tower grounding lightning protection test device as claimed in claim 5, characterized in that: ADC data acquisition is performed on the preprocessed signal. The specific method includes: Configure ADC parameters. According to actual needs, determine the sampling rate and number of channels of the ADC. The sampling rate should be at least twice the maximum frequency of the input signal. Determine the sampling bit number and number of sampling points of the ADC. The sampling is performed using an 8-fold sampling multiple and DMA is used to transfer the data to a defined array. The array size is M*N, where M is the number of channels and N is the number of sampling points. The array storage order is 1-M repeated storage. Each sampling is triggered by the TIM1 timer. When the number of samples reaches M*N, the array defined by A is split into arrays of 8 signals. The data can be processed by configuring a DMA full interrupt.

8. A high voltage tower grounding lightning protection test device as claimed in claim 5, characterized in that: The data after ADC data acquisition is subjected to digital signal processing according to a preset rule, wherein the preset rule is Fourier transform processing; for a periodic function, the Fourier series representation is defined as: Where T is the period of the function, F n is the Fourier expansion coefficient, F n for: For real-valued functions, their Rieger series can be written as: where a n and b n It is the amplitude of the real frequency component. A periodic signal is composed of an infinite number of sine and cosine waves. When the amplitude of the signal is to be obtained, the signal is transformed by Fourier transform to obtain the amplitude of the corresponding frequency.

9. A high-voltage tower grounding lightning protection test device as claimed in claim 8, characterized in that: When the ADC sampling frequency is Fs, the sampling signal frequency is f, and the number of sampling points is N, the sampling signal resolution is Fs / N. The frequency of the signal to be sampled is the (Fs / N+f)th point of the Fourier transform. The first point is the DC component. The amplitude K obtained by the Fourier transform is converted to the DC component amplitude L of the signal. 直流 =K / N, AC component amplitude L 交流 =K / (N / 2).

10. A high voltage tower grounding lightning protection test device as claimed in claim 8, characterized in that: When the ADC sampling frequency is Fs, the number of sampling points is N, and the transmitter transmission signal is P, the sampling signal resolution is Fs / N. At this time, the maximum modulus value obtained by Fourier transform is the sampling point position P / (Fs / N) when the transmission signal is P, that is, the P / (Fs / N)+1th value is the maximum value of Fourier transform.

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