A shunt integrated assembly with temperature acquisition and signal processing method and device

Abstract

The present application belongs to the technical field of shunt, and particularly relates to a shunt integrated assembly and signal processing method and device with temperature acquisition, which is configured with a shunt body with a current wiring guide rod and a red copper mounting flange. Temperature data is acquired by a temperature acquisition module built in the body. The temperature data is collected by a signal collection module and transmitted to a signal processing unit. The signal processing unit analyzes and processes the temperature data and synchronously acquired current data. The processed data is uploaded to an upper computer, and current-temperature relationship data and equipment state judgment results are output. The method effectively overcomes the influence of shunt resistance drift with temperature on measurement through integrated 16-point current sampling and real-time temperature compensation, and realizes high-stability current measurement under extra-high voltage direct current conditions.

Description

Technical Field

[0001] This invention belongs to the field of shunt technology, specifically relating to a shunt integration assembly and signal processing method and device with temperature acquisition. Background Technology

[0002] An ultra-high voltage direct current (UHVDC) shunt is a device used to measure the current in UHVDC transmission lines. The shunt is connected in series with the DC line. Currently, the main structure of an UHVDC shunt consists of a central manganese-copper alloy resistor as a sampling resistor, which converts the current data from the DC line into a voltage signal. The subsequent processing unit uses the acquired voltage signal to calculate the current magnitude. The two side structures are made of copper, primarily used for assembling and connecting the shunt with other structures and for welding to the central manganese-copper alloy.

[0003] When using related technologies for voltage sampling, if the local resistance at the sampling point deviates from the overall average resistance due to material defects, residual stress, or micro-temperature differences, the sampled value cannot represent the true voltage drop of the entire resistive element, resulting in a systematic bias in the measurement results. Furthermore, the resistivity of the manganese-copper alloy in the shunt varies significantly with temperature. In outdoor operating environments, drastic temperature changes and the thermal effect of its own current can cause large fluctuations in resistance. Without effective temperature coefficient compensation, errors will occur at both ends of the temperature range, affecting the accuracy of the acquired signal. Summary of the Invention

[0004] This invention provides an integrated assembly and signal processing method for a shunt with temperature acquisition. By using multi-point temperature sampling and real-time synchronous compensation, the drift of the shunt resistance value with temperature changes is offset, achieving consistent current measurement accuracy over a wide temperature range. Multi-point sampling of current data reduces errors in current data acquisition caused by the unevenness of the manganese-copper resistors.

[0005] The methods include: S1: Configure the shunt body, which is provided with a current wiring rod and a copper mounting flange; S2: By setting a temperature acquisition module and multiple current acquisition points in the shunt body, the temperature data at the copper mounting flange and the current data generated by the manganese copper part in the middle of the shunt are collected. S3: The signal collection module installed in the shunt body receives temperature data and current data from the temperature acquisition module, and collects the temperature data and current data. S4: Transmit the collected temperature and current data to the signal processing unit; S5: The signal processing unit performs synchronous analysis on the received temperature and current data; S6: Based on the results of synchronous analysis, output the correspondence data between current and temperature and the status judgment results; also transmit the status judgment results to the host computer.

[0006] It should be further explained that in S3 and S4, receiving temperature data and current data from the temperature acquisition module, and then collecting and transmitting the collected temperature data and current data to the signal processing unit specifically includes the following steps: S31: The output interfaces of the temperature acquisition modules mounted on the two PCBs are connected to the signal collection module on the inner flange of the shunt via multiple wire harnesses; the signal collection module is connected to the signal processing unit. S32: The signal processing unit uses a hardware timer interrupt as a trigger signal to synchronously start the analog-to-digital converter, sample and quantize the voltage signals from the two temperature acquisition modules respectively, and generate two sets of digital temperature raw data. S33: The signal processing unit calls a preset filtering algorithm to smooth the two sets of digital temperature raw data. Then, based on a preset weighting factor related to the thermal response characteristics of the temperature acquisition module installation location, it performs a weighted fusion operation on the two sets of data to obtain a fused temperature value that characterizes the thermal state of the shunt body.

[0007] It should be further explained that S5 specifically includes the following steps: S51: The signal processing unit reads the raw digital temperature values ​​and corresponding temperature change coefficients collected and stored in step S3 from the memory chip in a loop. S52: When the signal processing unit reads each set of temperature data, it calls its internal hardware clock to set a timestamp for the current set of data. S53: Based on the two read digital temperature values ​​and their corresponding relationship, the signal processing unit, combined with the temperature change coefficient obtained from the memory chip, calculates in real time the comprehensive temperature compensation coefficient used to characterize the overall resistance temperature characteristics of the current shunt body through a preset interpolation calculation model. S54: The signal processing unit uses the generated timestamp to align and synchronize the calculated comprehensive temperature compensation coefficient with the acquired raw current sampling data that has the same timestamp.

[0008] It should be further explained that S53 specifically includes the following steps: S531: The signal processing unit reads the installation angle parameters of the PCB board where the two temperature acquisition modules are located, and calculates the regional weighting coefficients corresponding to the two temperature values ​​by combining the inner and outer diameters of the manganese copper ring of the shunt body. S532: The signal processing unit multiplies the two digital temperature values ​​by the corresponding region weighting coefficients, and obtains the average temperature value of the manganese copper ring by weighting. It then calls the resistance-temperature calibration coefficients pre-stored in the memory chip to calculate the resistance change rate under the average temperature. S533: The signal processing unit converts the resistance change rate into a comprehensive temperature compensation coefficient, binds the timestamp of the current group of data, and saves the compensation coefficient, waiting to be synchronized and bound with the current sampling data.

[0009] It should be further explained that S54 specifically includes the following steps: S541: The master clock source simultaneously drives the current sampling analog-to-digital converter (ADC) and the hardware timer that adds timestamps to temperature data frames, unifying the time base of the two data streams; S542: Define two independent first-in-first-out buffer queues, which are used to store the original current sampling point sequence with timestamps and the temperature compensation coefficient sequence with timestamps (K(T), tT) respectively, and obtain the relative time offset based on the timestamps of the data at the head of the two queues; S543: When real-time compensation calculation is required, the coefficient K(T) that satisfies |ti-tT|≤Δt is searched in the temperature compensation coefficient queue based on the timestamp ti of the original current sampling point to be processed; Δt is the preset synchronization tolerance window. The original current value is multiplied by K(T) using a hardware multiplier to obtain the final current value Icomp after temperature compensation at the sampling point, and a timestamp ti is added to the output.

[0010] It should be further explained that the synchronous analysis of temperature and current data in S5 specifically includes the following steps: S511: Locks the current sampling clock of the signal processing unit and the timing clock that sets the timestamp for the temperature data to the main clock source to achieve hardware synchronization of the sampling time. S512: For each raw current data point acquired by the current sampling clock, the signal processing unit performs interpolation matching in the buffered timestamp-temperature compensation coefficient sequence according to the sampling time to obtain the real-time temperature compensation coefficient corresponding to the current sampling point. S513: The signal processing unit performs a continuity test on the current value after obtaining the real-time temperature compensation coefficient in step S512 and the current values ​​after temperature compensation at multiple original current sampling points adjacent to the sampling time, and calculates its rate of change and consistency residual. S514: Within a set statistical analysis period, the signal processing unit continuously compares the difference between the average current value calculated from sampling points on different PCB boards and the main current value after synchronous temperature compensation, and generates evaluation parameters characterizing the consistency of the measurement system.

[0011] It should be further explained that step S513 specifically includes the following steps: S5131: The signal processing unit extracts the current value Icurrent that has been applied with the real-time temperature compensation coefficient, and also extracts the sequence of M original current sample values ​​Icomp[-M / 2]...Icomp[+M / 2] that are adjacent to the current time after the same temperature compensation processing, forming a continuity test window with a length of 2*(M / 2)+1; S5132: Perform time-weighted least-squares linear fitting on the current value sequence within the continuity test window, calculate the instantaneous rate of change di / dt of the current value in the central region of the window, and calculate the absolute value of the residual of the current value at each sampling point relative to the fitted curve. S5133: Sort the absolute values ​​of the calculated residuals, remove the top K largest residual values, calculate the root mean square value of the remaining residuals as the consistency residual index of the continuity test window, and compare the consistency residual index with the preset threshold.

[0012] The present invention also provides a multi-point sampling ultra-high voltage DC shunt, comprising: multiple PCB boards, a shunt body, current wiring rods, a signal aggregation module, and a signal processing unit; The shunt body is connected to the copper mounting flange; the current connection rod is fixedly connected to the outer end face of the copper mounting flange. Multiple PCBs are evenly arranged on the inner ring surface of the shunt body; A temperature acquisition module is installed on the PCB board; The PCB board is connected to the signal aggregation module via a wiring harness, and the signal aggregation module is installed on the inner flange of the splitter. The signal aggregation module is connected to the signal processing unit. The signal aggregation module receives temperature data and current data from the temperature acquisition module and aggregates the temperature and current data. The aggregated temperature and current data are then transmitted to the signal processing unit. The signal processing unit performs synchronous analysis on the received temperature and current data. Based on the results of the synchronous analysis, it outputs the correspondence between current and temperature and the status judgment result. The status judgment result is also transmitted to the host computer.

[0013] It should be further explained that the shunt body is a ring-shaped manganese copper resistor. The upper and lower end faces of the shunt body are respectively fused together with two copper mounting flanges by electron beam welding to form an integral whole, constituting the main current flow path. The ring-shaped manganese copper resistor provides a standard sampling resistor, and the flanges provide a high-current interface for connecting to the primary circuit.

[0014] It should be further noted that the signal aggregation module is fixedly installed on the surface or inside the flange of the splitter; The signal processing unit is placed inside the signal processing unit compartment; the signal processing unit compartment is a cavity on the shunt housing, which isolates the signal processing unit from the external environment; The metal shunt housing encapsulates the shunt body, PCB board, wiring harness, and signal aggregation module.

[0015] As can be seen from the above technical solutions, the present invention has the following advantages: The multi-point sampling UHVDC shunt converter and method provided by this invention uses a manganese copper resistor, machined into a single circular ring, as the current path, thereby eliminating the current sharing problem of multiple conductors in parallel. Combined with electron beam vacuum welding, this ensures the uniformity and stability of the current path. Multiple PCBs are evenly arranged inside the manganese copper ring, with each PCB corresponding to a sampling point, directly sensing the voltage drop across the manganese copper resistor. The temperature acquisition module is integrated on the PCB, closely attached to the heat-affected zone of the manganese copper ring, resulting in low thermal resistance and a short temperature response time. The acquired temperature data directly reflects the operating temperature of the manganese copper resistor, providing accurate raw data for compensation calculations.

[0016] The signal aggregation module of this invention is embedded in the inner flange of the shunt, resulting in a short distance between it and the wiring harness at the sampling point and low signal transmission loss. The module performs equalization processing on multiple sampled signals, reducing random errors in single-point sampling and improving the consistency of current measurement.

[0017] The signal processing unit is housed within a compartment inside the metal shunt housing. Both the signal lines and the processing unit are shielded, preventing external electromagnetic interference from penetrating. The fully sealed housing isolates it from dust and rain, allowing the shunt to operate for extended periods in extreme outdoor environments. Attached Figure Description

[0018] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 Schematic diagram of a multi-point sampling ultra-high voltage DC shunt; Figure 2 This is a schematic diagram of the splitter body; Figure 3 This is a schematic diagram of the signal processing unit compartment; Figure 4 This is a schematic diagram of an embodiment of the signal processing unit compartment; Figure 5 Flowchart of the integrated assembly and signal processing method for a shunt with temperature acquisition.

[0020] Explanation of reference numerals in the attached figures: 1-Shunter body, 2-PCB board, 3-Wire harness, 4-Temperature acquisition module, 5-Signal aggregation module, 6-Shunter inner flange, 7-Copper mounting flange, 8-Shunter housing, 9-Signal processing unit, 10-Signal processing unit compartment, 11-Current wiring rod. Detailed Implementation

[0021] like Figures 1 to 4 As shown, the method provided by this invention is based on a multi-point sampling UHVDC shunt. Specifically, the shunt body 1 is connected to a copper mounting flange 7. The shunt body 1 is a ring-shaped manganese-copper resistor. The upper and lower end faces of the shunt body 1 are respectively fused together with two copper mounting flanges 7 by electron beam welding to form a whole. This constitutes the main current flow path. The manganese-copper part provides a standard sampling resistor, while the flanges provide a high-current interface for easy connection to the primary circuit.

[0022] The current connection rod 11 is fixedly connected to the outer end face of the copper mounting flange 7. It can introduce and lead the large current from the external UHVDC bus into and out of the shunt body 1, and is the physical access point for current data acquisition.

[0023] Multiple PCBs 2 are evenly arranged on the inner ring surface of the shunt body 1. This enables spatial multi-point, in-situ sampling of voltage signals. Each PCB corresponds to a sampling point, used to directly sense the voltage drop generated by the current flowing through the manganese-copper resistor, which is the initial source of current and temperature data.

[0024] Temperature acquisition module 4 is mounted on PCB board 2, placing the temperature sensor directly at the critical temperature measurement point. It converts the operating temperature of the shunt unit—a key physical quantity—into an electrical signal, providing raw data for temperature compensation.

[0025] PCB board 2 is connected to signal aggregation module 5 via wiring harness 3. All voltage signals acquired on PCB board 2 are converged in parallel to the input terminal of signal aggregation module 5 via their respective wiring harnesses 3. Signal aggregation module 5 is mounted on the inner flange 6 of the shunt.

[0026] In this embodiment, the signal aggregation module 5 is mechanically fixed to the surface or internal space of the inner flange 6 of the shunt. The signal aggregation module 5 equalizes the voltage signals from multiple sampling points.

[0027] The signal collection module 5 is connected to the signal processing unit 9, and collects current sampling data and temperature data to the signal processing unit.

[0028] The signal processing unit 9 is housed within the signal processing unit compartment 10. The signal processing unit compartment 10 is a sealed cavity within a metal shunt housing 8, isolating the signal processing unit 9 from the external environment. The metal housing forms a continuous electromagnetic shield, providing Faraday cage protection for the sensitive internal electronic circuitry and signal harnesses, ensuring electromagnetic interference resistance. The shunt housing 8 surrounds and seals the entire internal structure, encapsulating all internal components, including the shunt body 1, PCB board 2, wiring harness 3, and signal aggregation module 5, ensuring the reliability and stability of the internal measurement circuitry in industrial environments.

[0029] The following describes in detail the shunt integration assembly and signal processing method with temperature acquisition involved in this application. Specific details such as particular system structures and technologies are presented for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application can also be implemented in other embodiments without these specific details.

[0030] It should be understood that, when used in this specification, the term "comprising" indicates the presence of the described feature, integral, step, operation, element, and / or component, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof. The terms "comprising," "including," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0031] The terms "one embodiment" or "some embodiments" used in this application mean that one or more embodiments of this application include the specific features, structures, or characteristics described in that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this application do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized.

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Please see Figure 5 The diagram shows a flowchart of a shunt integration assembly and signal processing method with temperature acquisition in a specific embodiment. The method includes: S1: Configure the shunt body, which is equipped with a current wiring rod and a copper mounting flange.

[0034] In some embodiments, the shunt body 1 is a ring-shaped manganese copper resistor, that is, a manganese copper ring, which is welded and fixed to the copper mounting flanges 7 on both sides. The manganese copper alloy has a low temperature coefficient, and the ring structure can reduce the cumulative assembly error and ensure uniform resistance distribution.

[0035] S2: By using the temperature acquisition module and 16 current acquisition points installed in the shunt body, the temperature data at the copper mounting flange and the current data generated by the manganese copper part in the middle of the shunt are collected.

[0036] In some embodiments, an NTC thermistor or other temperature sensing chip is used as a temperature acquisition module 4 and fixed on the pads of the PCB board 2. The two PCB boards 2 of the temperature acquisition module 4 are fixed to the inner side of the manganese copper ring with screws.

[0037] In this embodiment, the manganese-copper resistor is the main heat-generating area. Heat is transferred to the flange through thermal conduction. The PCB is installed close to the flange to reduce thermal resistance, allowing the temperature acquisition module 4 to quickly sense temperature changes at the solder joint. The resistance of the NTC thermistor changes exponentially with temperature, and the temperature can be indirectly calculated by measuring its voltage drop.

[0038] S3: The temperature data from the temperature acquisition module is received by the signal collection module installed in the shunt body, and the temperature data is collected.

[0039] In one embodiment of the present invention, step S3, receiving temperature data from the temperature acquisition module and collecting the temperature data, specifically includes the following steps: S31: The output interfaces of the temperature acquisition modules 4, which are installed on the two PCB boards 2, are connected to the signal collection module 5 on the inner flange 6 of the shunt via multiple wire harnesses; the signal collection module 5 is connected to the signal processing unit.

[0040] It should be noted that 16 current acquisition signal lines and two temperature signal lines can all be converged to the signal aggregation module. The 16 current acquisition signal lines are combined into a single signal line and input to the signal processing unit. The 16 current acquisition signal lines are equalized on the signal aggregation module, while the two temperature signal lines are not processed and are directly transferred to the signal processing unit.

[0041] Optionally, the signal processing unit includes a main control processor, operational amplifiers, an analog-to-digital converter (ADC), and a power supply. The main control processor is an Altera MAX10 series FPGA, which offers fast real-time response and a significant advantage in processing speed compared to an MCU. The FPGA is responsible for triggering the ADC conversion and reading the digital signal.

[0042] The following is the shunt temperature calibration procedure and an optional method for current compensation: Place the shunt in the high and low temperature test chamber and pass the rated current through it. The function of the high and low temperature chamber is to set the ambient temperature of the shunt.

[0043] The high and low temperature test chamber sets a temperature point every 10℃, and the temperature coefficient of the shunt is obtained at the set temperature.

[0044] For example, a rated standard current of 5000A is applied at room temperature (20℃), and the shunt temperature coefficient at room temperature is calculated by the deviation between the collected current value and the actual current value. The shunt coefficients at other temperature points are obtained in the same way. The temperature range is -40℃ to 70℃, and the calibration temperature points are -40℃, -30℃, -20℃, -10℃, 0℃, 10℃, 20℃, 30℃, 40℃, 50℃, 60℃, and 70℃. To save time, the other temperature points are obtained through coefficient fitting. That is, the temperature coefficients at 12 temperature points are fitted by software to obtain a coefficient curve, thus yielding the temperature coefficient for the entire temperature range. A temperature coefficient is taken every 0.5℃, and the obtained temperature coefficient and its corresponding temperature are then written into a memory chip. The shunt has a temperature sensing module that monitors the shunt temperature in real time. The signal processing unit reads the temperature coefficient from the memory chip in real time based on the shunt temperature value and uses the read temperature coefficient to correct the collected current value.

[0045] S32: The signal processing unit uses the main clock source interrupt as a trigger signal to synchronously start the analog-to-digital converter, sample and quantize the voltage signals from the two temperature acquisition modules respectively, and generate two sets of digital temperature raw data.

[0046] In some embodiments, after clock configuration, one of the general-purpose timers is set to generate periodic update events at a frequency of 10 Hz. These update events are directly mapped to the external trigger inputs of the microcontroller's two ADCs. When the trigger signal arrives, the sample-and-hold circuits of both ADCs capture the instantaneous voltage values ​​on their respective input pins on the same clock edge, and then begin independent quantization processes.

[0047] An interrupt is generated after the ADC conversion is completed. The microcontroller's interrupt service routine reads the values ​​from the two ADC data registers in sequence. These two values ​​are the ratios of the sensor voltage to the ADC reference voltage.

[0048] S33: The signal processing unit calls a preset filtering algorithm to smooth the two sets of digital temperature raw data, and then performs a weighted fusion operation on the two sets of data based on a preset weighting factor related to the thermal response characteristics of the installation position of the temperature acquisition module 4, to obtain a fused temperature value that characterizes the thermal state of the shunt body 1.

[0049] In some embodiments, after obtaining two preliminary temperature data points T1 and T2, they are fed into a first-order infinite impulse response digital filter for smoothing to suppress any random white noise that may be mixed in. Weighting coefficients stored in flash memory are then invoked. For example, the weight of a probe near the geometric center of the ring is set to 0.7, and that near the edge is set to 0.3. The calculation is performed: Tf = 0.7 * T1 + 0.3 * T2. Before each calculation, the difference between T1 and T2 is compared to see if it exceeds a threshold. If it does, backup logic is activated, and the valid temperature value Tf from the previous cycle is used.

[0050] S34: Query the pre-stored resistance-temperature characteristic parameter table based on the fusion temperature value, and calculate the resistance temperature coefficient at the current temperature using linear interpolation to form a temperature compensation data package.

[0051] In some embodiments, the signal processing unit is equipped with a memory chip, which is an FRAM memory chip. The memory chip stores a lookup table, and each entry consists of two fields: a temperature index value and the temperature coefficient of resistance α of the manganese-copper alloy corresponding to the temperature point.

[0052] After obtaining Tf, the signal processing unit compares it with the temperature index in the lookup table one by one to find the largest index value Tlow less than or equal to Tf and its corresponding coefficient αlow, and the smallest index value Thigh greater than Tf and its corresponding coefficient αhigh.

[0053] Perform linear interpolation calculation: αc = αlow + ((Tf - Tlow) / (Thigh - Tlow)) * (αhigh - αlow). The signal processing unit packages the calculated αc, timestamp, and status word into a data packet.

[0054] S4: Transmit the temperature data collected by the signal collection module to the signal processing unit.

[0055] In some embodiments, the data output port of the signal aggregation module 5 is communicatively connected to the I2C communication interface of the signal processing unit 9.

[0056] S5: The signal processing unit performs synchronous analysis on the received temperature and current data.

[0057] Optionally, the shunt can collect both current and temperature data. Up to 16 PCB acquisition boards can be configured to collect current data. Two of these 16 PCB acquisition boards integrate temperature acquisition modules to collect temperature data.

[0058] In some embodiments, the same master clock source ensures the timing consistency of temperature and current data, eliminating crystal oscillator drift errors. Interpolation matching ensures that each current sampling point corresponds to a precise temperature coefficient, offsetting the effect of temperature drift from the manganese copper ring resistor. Timing dataset and fitting analysis can eliminate transient abnormal data, and multi-point mean comparison can assess the overall stability of the measurement system, ensuring that the data conforms to actual operating conditions.

[0059] S6: Based on the results of synchronous analysis, output the correspondence data between current and temperature and the status judgment results; also transmit the status judgment results to the host computer.

[0060] In some embodiments, the signal processing unit 9 sorts the synchronously analyzed result data according to the sampling point number of the PCB board 2, and generates a result table containing the sampling point ID, temperature value, corrected current value, timestamp, and evaluation parameters. Based on stored thresholds, temperatures exceeding the threshold range are marked as temperature abnormalities, current exceeding the rated range is marked as current abnormalities, both exceeding the range are marked as severe abnormalities, and no values ​​exceeding the range are marked as normal. The results are output to the host computer, simultaneously triggering the corresponding indicator lights on the shunt housing 8: green for normal, yellow for abnormal, and red for severe abnormalities. Abnormal results are associated with the sampling point number and timestamp and recorded in the fault log.

[0061] In one embodiment of the present invention, based on step S5, the following is a possible embodiment and its specific implementation is described in a non-limiting manner. In S5, the signal processing unit processes the received temperature data and performs synchronous analysis with the acquired current data, specifically including the following steps: S51: Signal processing unit 9 reads from the storage chip the original digital temperature values ​​and corresponding temperature change coefficients collected and stored in step S3 in a cyclic manner.

[0062] S52: The signal processing unit 9 is equipped with a clock circuit as the master clock source. When reading each group of temperature data, the master clock source is called to set a timestamp for the current group of data.

[0063] S53: Based on the two read digital temperature values ​​and their corresponding relationship, and combined with the temperature change coefficient obtained from the memory chip, the signal processing unit 9 calculates in real time the comprehensive temperature compensation coefficient used to characterize the overall resistance temperature characteristics of the current shunt body 1 through a preset interpolation calculation model.

[0064] In some embodiments, S53 specifically includes the following steps: S531: The signal processing unit 9 reads the installation angle parameters of the PCB board 2 where the two temperature acquisition modules 4 are located, and calculates the regional weighting coefficients corresponding to the two temperature values ​​by combining the inner and outer diameters of the manganese copper ring of the shunt body 1.

[0065] In some embodiments, the signal processing unit 9 extracts the circumferential mounting angles of the PCB board 2 corresponding to the two temperature acquisition modules 4, which are denoted as θ1 and θ2 respectively.

[0066] Furthermore, combining the inner diameter D and outer diameter d of the manganese copper ring of the shunt body 1, the coverage arc length corresponding to each temperature acquisition module (4) is calculated as L1=θ1×π×(D+d) / 4, L2=θ2×π×(D+d) / 4. The proportion of the arc length to the total circumference is used as the regional weight coefficient w1=L1 / (π×(D+d)), w2=L2 / (π×(D+d)), and the weight coefficient is retained to four decimal places to ensure that w1+w2=1.

[0067] It can be seen that the temperature distribution of the manganese-copper ring is positively correlated with the arc length covered by the sampling points; the larger the arc length, the greater the impact of the temperature in the corresponding area on the overall resistance. By calculating the arc length ratio through the installation angle and the ring size, the contribution of two temperature points to the overall resistance can be quantified, avoiding the impact of local deviations at a single temperature point on the compensation accuracy.

[0068] S532: Signal processing unit 9 multiplies the two digital temperature values ​​by the corresponding region weighting coefficients, and obtains the average temperature value of the manganese copper ring by weighting. It then calls the resistance-temperature calibration coefficients pre-stored in the memory chip to calculate the resistance change rate under the average temperature.

[0069] In some embodiments, the signal processing unit 9 multiplies the two read digital temperature values ​​T1 and T2 by the corresponding weighting coefficients w1 and w2 respectively, calculates the average temperature Tavg=T1×w1+T2×w2, and retains two decimal places.

[0070] Read the pre-stored resistance value R0 at reference temperature T0 from the memory chip, along with the first-order temperature coefficient α and the second-order temperature coefficient β, and substitute them into the following formula: ΔR / R0 = α × (Tavg - T0) + β × (Tavg - T0)², calculate the rate of change of resistance.

[0071] S533: The signal processing unit converts the resistance change rate into a comprehensive temperature compensation coefficient, binds the timestamp of the current group of data, and saves the compensation coefficient, waiting to be synchronized and bound with the current sampling data.

[0072] In some embodiments, the signal processing unit converts the resistance change rate ΔR / R0 into a comprehensive temperature compensation coefficient K(Tavg) = 1 + ΔR / R0. It then calls the timestamp tT generated in step S52, binds K(Tavg) to tT, and saves it.

[0073] S54: The signal processing unit uses the generated timestamp to align and synchronize the calculated comprehensive temperature compensation coefficient with the acquired raw current sampling data that has the same timestamp.

[0074] In some embodiments, the signal processing unit continuously digitizes and stores the raw current data stream into a buffer using a high sampling rate ADC, with each current point defining a timestamp ti for the sampling time.

[0075] For the data with the received timestamp t generated in step S52 T The temperature compensation coefficient K(T) data stream is used. The data is aligned, and for each latest timestamp ti, the temperature coefficient buffer is searched for the compensation coefficient K(T) that minimizes |ti-tT|. If found, the original current value Iraw at this current sampling point is multiplied by the corresponding compensation coefficient K(T) to obtain the compensated current value Icomp = Iraw * K(T).

[0076] The compensated current value Icomp undergoes data processing to generate the final measurement result, which is then uploaded to the host computer. The current value output by signal processing unit 9 is always calibrated to the standard reference temperature. This ensures the entire measurement system maintains its nominal accuracy across the entire temperature range, improving measurement reliability and meeting the requirements of UHVDC projects for adaptability to extreme environments.

[0077] As one implementation of this application, S54 specifically includes the following steps: S541: The master clock source simultaneously drives the current sampling analog-to-digital converter (ADC) and the hardware timer that adds timestamps to temperature data frames, unifying the time base of the two data streams.

[0078] S542: Define two independent first-in-first-out (FIFO) buffer queues, one for storing the timestamped sequence of raw current sampling points (Iraw, ti) and the other for storing the timestamped sequence of temperature compensation coefficients (K(T), tT). The relative time offset of the two queues is dynamically maintained based on the timestamps of the data at the head of each queue.

[0079] In some embodiments, the dual-queue buffer is based on the fact that ADC and temperature compensation coefficient calculation are two independent processing methods. By setting up two first-in-first-out queues, it is equivalent to setting up two buffer areas, which can be processed continuously without interruption.

[0080] S543: When real-time compensation calculation is required, the coefficient K(T) that satisfies |ti-tT|≤Δt is searched in the temperature compensation coefficient queue based on the timestamp ti of the original current sampling point to be processed; Δt is the preset synchronization tolerance window. The final current value Icomp at the sampling point after temperature compensation is obtained by multiplying Iraw with K(T) using a hardware multiplier, and a timestamp ti is added to the output.

[0081] In some embodiments, when the compensation calculation task is scheduled to be executed, the next sampling point to be processed is taken from the original current queue, and the value Iraw and the timestamp ti are recorded.

[0082] A timestamp-based binary search is used to quickly locate a timestamp tT in the temperature coefficient queue, such that the absolute value of the time difference between tT and ti is less than a preset, very small threshold Δt. This threshold represents the maximum allowed synchronization error of the system. Once found, the corresponding coefficient K(T) is retrieved from the queue.

[0083] The multiplication operation Icomp = Iraw * K(T) is performed by the hardware multiplier of signal processing unit 9. The calculated Icomp is assigned the same timestamp ti as Iraw and sent to the next processing stage or output buffer. This is effective for tracking rapidly changing fault currents and harmonics, as rapid current changes may be accompanied by rapid temperature changes in the resistive element. Precise time alignment ensures the compensation accuracy during the process. Ultimately, each Icomp value output to the host computer is a corrected real current value, meeting the high fidelity requirements of UHVDC systems for measurement data.

[0084] In one embodiment of the present invention, based on step S5, the following is a possible embodiment and its specific implementation is described in a non-limiting manner. In S5, the synchronous analysis of temperature data and current data specifically includes the following steps: S511: Locks the current sampling clock of the signal processing unit and the timing clock that sets the timestamp for temperature data to the master clock source to achieve hardware synchronization of the sampling time.

[0085] In some embodiments, the bias caused by clock source differences can be eliminated. If current sampling and temperature marking use two independent clocks, due to the slight differences in the actual frequency of each crystal oscillator and the drift over time with temperature, these two clocks will accumulate a time difference after running for a period of time. Software timestamp alignment can only correct communication delays, but cannot correct the underlying drift caused by this clock source asynchrony. Locking both to the same master clock source ensures that the entire system has only one time.

[0086] S512: For each raw current data point acquired by the current sampling clock, the signal processing unit (9) performs interpolation matching in the cached timestamp-temperature compensation coefficient sequence according to the sampling time to obtain the real-time temperature compensation coefficient corresponding to the current sampling point.

[0087] In some embodiments, the high-speed ADC of the signal processing unit continuously samples the current at a fixed, known period to generate a sequence of equally spaced current data points C[t1], C[t2], C[t3]..., each point having a precise sampling time.

[0088] The temperature compensation coefficient K(T) is updated at a low frequency, forming a sparse sequence K[T1], K[T2], ... Here, for each current sampling time ti, the most suitable compensation coefficient K is found. The system performs linear interpolation: find the two nearest temperature coefficient timestamps Tm and T{m+1} before and after ti, and the corresponding coefficient values ​​Km and K{m+1}. Define the temperature coefficient as changing linearly between these two times, and then calculate a virtual coefficient value Ki at time ti according to the formula Ki=Km+(K{m+1}-Km)*(ti-Tm) / (T{m+1}-Tm). This Ki is the compensation coefficient that corresponds precisely to the current sampling point C[ti] in time.

[0089] S513: The signal processing unit performs a continuity check on the current value after obtaining the real-time temperature compensation coefficient in step S512 and the current values ​​after temperature compensation at multiple original current sampling points adjacent to that moment, and calculates its rate of change and consistency residual.

[0090] Step S513 in this embodiment specifically includes the following steps: S5131: The signal processing unit extracts the current value Icurrent that has been applied with the real-time temperature compensation coefficient, and also extracts the sequence of M original current sample values ​​Icomp[-M / 2]...Icomp[+M / 2] that are adjacent to this moment after the same temperature compensation processing, forming a continuity test window with a length of 2*(M / 2)+1.

[0091] S5132: Perform time-weighted least-squares linear fitting on the current value sequence within the continuity test window, calculate the instantaneous rate of change di / dt of the current value in the central region of the window, and calculate the absolute value of the residual of the current value at each sampling point relative to the fitted curve.

[0092] In some embodiments, the signal processing unit obtains a sequence of current values ​​{I} with a time offset. comp，i , Δt i After that, assign a weight coefficient to each data point within the window. The weighting function uses a Gaussian or Hanning window, with the highest weight at the center point and gradually decreasing towards the edges of the window. This allows the test to better reflect the local trend near the current point and reduces the truncation effect that may exist at the window edges. Weighted least squares linear fitting is then performed: find Ifit(t) = a*t + b, such that the weighted sum of squared residuals for all data points is... Minimum. Where N is the total number of data points within the window participating in the fitting. I represents the time offset of the i-th data point relative to the center of the window. comp，i为 The current value of the i-th data point after temperature compensation.

[0093] By solving this optimization problem, the slope *a* and intercept *b* of the fitted line are obtained. The physical meaning of the slope *a* is the instantaneous rate of change of current *di / dt* in the central region of the current window. For each data point within the window, its residual *e[i]* = I is calculated. comp，i -(a* +b), and take the absolute value |e[i]|.

[0094] It should be noted that Ifit(t) is an idealized current change trend model constructed using a weighted least squares linear fitting algorithm within a specified continuity test time window. Ifit(t) compares each actual sampled value I_comp[i] with the value of Ifit(t) at that sampling time t[i], and the difference is the residual e[i] = I_comp[i] - I_fit(t[i]). The magnitude of the residual directly reflects the degree to which the sampling point deviates from the ideal smooth trend.

[0095] In step S5132, the physical current flowing through the shunt is constrained by the characteristics of the power grid load, exhibiting continuity and smoothness within the time window. Even with rapid changes, it should follow a certain rate of change. However, electromagnetic interference, sampling noise, or channel faults may cause abrupt changes or jumps in the current sampling values ​​that do not conform to physical laws. Step S5132 establishes a mathematical model Ifit(t) describing the trend of current change within a short time window to verify the rationality of each sampling value.

[0096] The weighted fitting here can use time weighting to ensure that the established trend model reflects the local features near the current sampling time. Giving higher weights to the current point and its neighboring points allows the fitted line Ifit(t) = a*t + b to be dominated by the trends of these points. This reduces the impact of edge effects; their smaller weights mean that even if the data contains interference or data from different trend segments, their influence on the trend judgment of the current point is limited. The key test is whether the trend of the current sampled value is consistent with that of its immediate neighbors. If the current point is a value caused by strong interference, even if it is within the window, it will produce a large residual e[i] because its value deviates significantly from the local trend determined by the high weights of surrounding points.

[0097] The instantaneous rate of change (di / dt = a) can be used to determine whether the system is in a transient process of drastic current change, providing a basis for different processing strategies.

[0098] The residual (e[i]) is the direct output of the test. The absolute value of the residual at each sampling point quantifies the degree to which the data at that point deviates from the ideal smooth trend. A residual greater than that at other points indicates that the point may be an abnormal interference point or a channel fault point. By constructing a weighted, localized trend baseline, the physical rationality of each current sampling point is measured. An adaptive and quantitative discrimination method is provided to identify and eliminate abnormal data that violate the physical law of continuous current change, ensuring that the final output current value reflects the true physical quantity under strong interference environment.

[0099] S5133: Sort the absolute values ​​of the calculated residuals, remove the top K largest residual values, calculate the root mean square value of the remaining residuals as the consistency residual index of the continuity test window, and compare the consistency residual index with the preset threshold.

[0100] In some embodiments, after obtaining the array of absolute residual values ​​|e[i]| of all data points within the window, the signal processing unit (9) calls a function to sort the array in ascending order. The largest K values ​​in the sorted array are then removed, for example, K=2, which means removing the two points most likely to be abnormal.

[0101] The K value for elimination can be configured based on the window size M and the expected interference density. The root mean square value is calculated for the remaining (2*(M / 2) + 1 - K) residuals: .

[0102] RMS residual It is the final consistency residual metric. represents the residual value of the j-th valid data point, and M is the number of valid data points after removing outliers. Based on the dynamic threshold of historical data, the adaptive test standard is realized, enabling the system to maintain the best anomaly detection performance in complex field environments and reducing the false alarm rate and false negative rate. S514: During the set statistical analysis period, the signal processing unit continuously compares the difference between the average current calculated from the sampling points of different PCB boards (2) and the main current value after synchronous temperature compensation, and generates evaluation parameters characterizing the consistency of the measurement system.

[0103] In some embodiments, multiple sampling points provide spatial redundancy. At any given moment, the readings are consistent. The synchronization analysis in step S514 aligns the temperature and current at different points in time, establishing a calibration reference based on data consistency. When the differences in readings between multiple points exceed the historical normal range, the system can provide early warning of potential fault risks, even if the final output value is normal.

[0104] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0105] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A shunt integrated assembly and signal processing method with temperature acquisition, characterized in that the method... include: S1: Configure the shunt body, which is provided with a current wiring rod and a copper mounting flange; S2: By setting a temperature acquisition module and multiple current acquisition points in the shunt body, the temperature data at the copper mounting flange and the current data generated by the manganese copper part in the middle of the shunt are collected. S3: The signal collection module installed in the shunt body receives temperature data and current data from the temperature acquisition module, and collects the temperature data and current data. S4: Transmit the collected temperature and current data to the signal processing unit; S5: The signal processing unit performs synchronous analysis on the received temperature and current data; S6: Based on the results of synchronous analysis, output the correspondence data between current and temperature and the status judgment results; also transmit the status judgment results to the host computer.

2. The shunt integration assembly and signal processing method with temperature acquisition according to claim 1, characterized in that, In steps S3 and S4, temperature data and current data are received from the temperature acquisition module, and the collected temperature data and current data are aggregated and transmitted to the signal processing unit. Specifically, this includes the following steps: S31: The output interfaces of the temperature acquisition modules (4) installed on the two PCB boards (2) are connected to the signal collection module (5) on the inner flange (6) of the shunt via multiple wire harnesses; the signal collection module (5) is connected to the signal processing unit. S32: The signal processing unit uses a hardware timer interrupt as a trigger signal to synchronously start the analog-to-digital converter, sample and quantize the voltage signals from the two temperature acquisition modules respectively, and generate two sets of digital temperature raw data. S33: The signal processing unit calls the preset filtering algorithm to smooth the two sets of digital temperature raw data, and then performs weighted fusion calculation on the two sets of data according to the preset weight factor related to the thermal response characteristics of the installation position of the temperature acquisition module (4) to obtain a fusion temperature value that characterizes the thermal state of the shunt body (1).

3. The shunt integration assembly and signal processing method with temperature acquisition according to claim 1, characterized in that, S5 specifically includes the following steps: S51: The signal processing unit (9) reads the original digital temperature value and the corresponding temperature change coefficient collected and stored in step S3 from the memory chip in a loop. S52: When reading each set of temperature data, the signal processing unit (9) calls its internal hardware clock to set a timestamp for the current set of data; S53: The signal processing unit (9) calculates the comprehensive temperature compensation coefficient in real time, based on the two digital temperature values ​​read and their corresponding relationship, combined with the temperature change coefficient obtained from the memory chip, through the preset interpolation calculation model, to characterize the overall resistance temperature characteristics of the current shunt body (1). S54: The signal processing unit (9) uses the generated timestamp to align and synchronize the calculated comprehensive temperature compensation coefficient with the collected original current sampling data with the same timestamp.

4. The shunt integration assembly and signal processing method with temperature acquisition according to claim 3, characterized in that, S53 specifically includes the following steps: S531: The signal processing unit (9) reads the installation angle parameters of the PCB board (2) where the two temperature acquisition modules (4) are located, and calculates the regional weight coefficients corresponding to the two temperature values ​​by combining the inner and outer diameters of the manganese copper ring of the shunt body (1). S532: The signal processing unit (9) multiplies the two digital temperature values ​​by the corresponding regional weighting coefficients respectively, and obtains the average temperature value of the manganese copper ring by weighting. It then calls the resistance-temperature calibration coefficient stored in the memory chip to calculate the resistance change rate under the average temperature. S533: The signal processing unit (9) converts the resistance change rate into a comprehensive temperature compensation coefficient, binds the timestamp of the current group data, and saves the compensation coefficient, waiting to be synchronized with the current sampling data.

5. The shunt integration assembly and signal processing method with temperature acquisition according to claim 3, characterized in that, S54 specifically includes the following steps: S541: The master clock source simultaneously drives the current sampling analog-to-digital converter (ADC) and the hardware timer that adds timestamps to temperature data frames, unifying the time base of the two data streams; S542: Define two independent first-in-first-out buffer queues, which are used to store the original current sampling point sequence with timestamps and the temperature compensation coefficient sequence with timestamps (K(T), tT) respectively, and obtain the relative time offset based on the timestamps of the data at the head of the two queues; S543: When real-time compensation calculation is required, the coefficient K(T) that satisfies |ti-tT|≤Δt is searched in the temperature compensation coefficient queue based on the timestamp ti of the original current sampling point to be processed; Δt is the preset synchronization tolerance window. The original current value is multiplied by K(T) using a hardware multiplier to obtain the final current value Icomp after temperature compensation at the sampling point, and a timestamp ti is added to the output.

6. The shunt integration assembly and signal processing method with temperature acquisition according to claim 1, characterized in that, In S5, the synchronous analysis of temperature and current data includes the following steps: S511: Lock the current sampling clock of the signal processing unit (9) and the timing clock that sets the timestamp for the temperature data to the main clock source to achieve hardware synchronization of the sampling time; S512: For each raw current data point acquired by the current sampling clock, the signal processing unit (9) performs interpolation matching in the buffered timestamp-temperature compensation coefficient sequence according to the sampling time to obtain the real-time temperature compensation coefficient corresponding to the current sampling point. S513: The signal processing unit (9) performs a continuity test on the current value after the real-time temperature compensation coefficient obtained in step S512 and the current value after temperature compensation of multiple original current sampling points adjacent to the sampling time, and calculates its rate of change and consistency residual. S514: The signal processing unit (9) continuously compares the difference between the average current value calculated from the sampling points of different PCB boards (2) and the main current value after synchronous temperature compensation within the set statistical analysis time period, and generates evaluation parameters characterizing the consistency of the measurement system.

7. The shunt integration assembly and signal processing method with temperature acquisition according to claim 6, characterized in that, Step S513 specifically includes the following steps: S5131: The signal processing unit (9) extracts the current value Icurrent that has been applied with the real-time temperature compensation coefficient, and also extracts the sequence of M original current sample values ​​Icomp[-M / 2]...Icomp[+M / 2] that are adjacent to the current time after the same temperature compensation processing, forming a continuity test window with a length of 2*(M / 2)+1; S5132: Perform time-weighted least-squares linear fitting on the current value sequence within the continuity test window, calculate the instantaneous rate of change di / dt of the current value in the central region of the window, and calculate the absolute value of the residual of the current value at each sampling point relative to the fitted curve. S5133: Sort the absolute values ​​of the calculated residuals, remove the top K largest residual values, calculate the root mean square value of the remaining residuals as the consistency residual index of the continuity test window, and compare the consistency residual index with the preset threshold.

8. A multi-point sampling ultra-high voltage DC shunt, characterized in that, The multi-point sampling ultra-high voltage DC shunt is used to realize the integrated assembly and signal processing method of the shunt with temperature acquisition as described in any one of claims 1 to 7; Includes: multiple PCB boards (2), shunt body (1), current wiring rod (11), signal aggregation module (5) and signal processing unit (9); The shunt body (1) is connected to the copper mounting flange (7); the current wiring rod (11) is fixedly connected to the outer end face of the copper mounting flange (7); Multiple PCBs (2) are evenly arranged on the inner ring surface of the shunt body (1); A temperature acquisition module (4) is installed on the PCB board (2); The PCB board (2) is connected to the signal aggregation module (5) via a wire harness (3), and the signal aggregation module (5) is installed on the inner flange (6) of the splitter; The signal collection module (5) is connected to the signal processing unit (9). The signal collection module (5) receives temperature data and current data from the temperature acquisition module and collects the temperature data and current data. It transmits the collected temperature data and current data to the signal processing unit. The signal processing unit performs synchronous analysis on the received temperature data and current data. Based on the results of the synchronous analysis, it outputs the correspondence data between current and temperature and the status judgment result. It also transmits the status judgment result to the host computer.

9. The multi-point sampling ultra-high voltage DC shunt according to claim 8, characterized in that, The shunt body (1) is a ring-shaped manganese copper resistor. The upper and lower end faces of the shunt body (1) are respectively fused together with two copper mounting flanges (7) by electron beam welding to form an integral whole, constituting the main path for current flow. The ring-shaped manganese copper resistor provides a standard sampling resistor, and the flanges provide a high-current interface for connecting to the primary circuit.

10. The multi-point sampling ultra-high voltage DC shunt according to claim 8, characterized in that, The signal aggregation module (5) is fixedly installed on the surface or inside the flange (6) of the splitter; The signal processing unit (9) is placed inside the signal processing unit compartment (10); the signal processing unit compartment (10) is a cavity on the splitter housing (8) to isolate the signal processing unit (9) from the external environment; The metal shunt housing (8) encapsulates the shunt body (1), PCB board (2), wire harness (3), and signal aggregation module (5).

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