Bus current detection method and device, storage medium and fluxgate Hall sensor

Abstract

The embodiment of the invention provides a bus current detection method and device, a storage medium and a fluxgate Hall sensor. Belongs to the technical field of current measurement. Comprising the following steps: in response to a detected current measurement instruction, inputting a preset driving voltage to an excitation coil; adding a zero voltage interval in the driving voltage, wherein the zero voltage interval corresponds to a fixed starting moment and a random ending moment of a saturation overcurrent point; in response to the termination moment, controlling the driving bridge arm of the excitation coil to turn over so as to turn over the voltage polarity of the excitation coil, and repeating the step of adding the zero voltage interval to the step of controlling the driving bridge arm of the excitation coil to turn over until the detection is completed; acquiring a voltage signal obtained by the amplifying circuit; and according to the voltage signal, the starting time and the ending time, determining the current of the measured bus. The problem that the sampling average value deviates due to the fact that the frequency used by a fluxgate Hall sensor is consistent with the frequency of a measured bus is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of current measurement, and in particular to a bus current detection method and device, a storage medium and a fluxgate hall sensor. BACKGROUND

[0002] In the field of new energy vehicles and commercial vehicles, the remaining capacity (SOC) of the battery system is a key parameter for ensuring the safe operation of the vehicle and optimizing energy management. Currently, high-precision fluxgate hall sensors are commonly used in the battery system to sample the bus current in real time, and an integral algorithm is used to calculate the SOC value.

[0003] Currently, in related technologies, a fixed positive and negative saturation frequency is usually used during sampling by the fluxgate hall sensor.

[0004] However, the inventors have found that the related technology at least has the following technical problems: when the frequency used by the fluxgate hall sensor is consistent with the frequency of the measured bus, the fluxgate hall sensor samples a non-complete cycle of the sinusoidal fluctuation, and the highest point or the lowest point of the sinusoidal fluctuation is missing, resulting in a deviation in the average value of the sampling. SUMMARY

[0005] The bus current detection method and device, the storage medium and the fluxgate hall sensor provided by the embodiments of the present application solve the problem of deviation in the average value of the sampling caused by the frequency used by the fluxgate hall sensor being consistent with the frequency of the measured bus.

[0006] In a first aspect, the embodiments of the present application provide a bus current detection method, which includes: in response to detecting a current measurement instruction, inputting a driving voltage of a preset size to an excitation coil; adding a zero voltage interval to the driving voltage, wherein the zero voltage interval corresponds to a fixed starting time and a random ending time of a saturation overcurrent point; in response to reaching the ending time, controlling a driving bridge arm of the excitation coil to flip so that the voltage polarity of the excitation coil is flipped, and repeating the step of adding the zero voltage interval until the step of controlling the driving bridge arm of the excitation coil to flip is completed; obtaining a voltage signal obtained by an amplification circuit; and determining the current size of the measured bus according to the voltage signal, the starting time and the ending time.

[0007] In a possible implementation, determining the current size of the measured bus according to the voltage signal, the starting time and the ending time includes: removing the voltage signal from the starting time to the corresponding ending time to obtain a residual voltage signal; and determining the current size of the measured bus according to the residual voltage signal.

[0008] In one possible implementation, determining the current magnitude of the bus under test based on the residual voltage signal includes: determining the characteristic information of the residual voltage signal; and finding a preset correspondence between the characteristic information and the current magnitude based on the characteristic information to obtain the current magnitude of the bus under test.

[0009] In one possible implementation, a zero-voltage interval is added to the driving voltage, including: randomly adding a zero-voltage interval to the driving voltage during the overcurrent phase after coil saturation.

[0010] In one possible implementation, a zero-voltage interval is added to the driving voltage, including: obtaining the current time; obtaining the coil current of the excitation coil; generating a start time based on the current time, the coil current, and a preset overcurrent saturation threshold; generating an end time based on the start time and a random number; and adding a zero-voltage interval to the driving voltage based on the start time and the end time.

[0011] In one possible implementation, the difference between the termination time and the start time is less than a preset duration threshold.

[0012] In one possible implementation, before adding a zero-voltage range to the driving voltage, the method further includes: controlling the driving voltage of the excitation coil using a preset mode; acquiring the historical voltage signal of the amplifier circuit; determining the historical current of the bus under test based on the historical voltage signal; and if the historical current of the bus under test is less than a preset current threshold, then performing the steps from inputting a preset voltage to the excitation coil to determining the current magnitude of the bus under test based on the voltage signal, the start time, and the end time.

[0013] Secondly, embodiments of this application provide a bus current detection device, comprising: a voltage input module for inputting a preset driving voltage to an excitation coil in response to a current measurement command; a voltage addition module for adding a zero-voltage interval to the driving voltage, wherein the zero-voltage interval corresponds to a fixed start time and a random end time of the saturation overcurrent point; a voltage reversal module for controlling the driving bridge arm of the excitation coil to reverse in response to reaching the end time, thereby reversing the voltage polarity of the excitation coil, repeating the step of adding a zero-voltage interval until the step of controlling the driving bridge arm of the excitation coil to reverse, until the detection is completed; a signal acquisition module for acquiring a voltage signal obtained by an amplification circuit; and a current determination module for determining the magnitude of the current of the bus under test based on the voltage signal, the start time, and the end time.

[0014] Thirdly, embodiments of this application provide a fluxgate Hall sensor, including: a control circuit, a drive circuit, an excitation coil, a soft magnetic core, and a Hall element; the control circuit is used to control the drive circuit to input a drive voltage to the excitation coil and add a zero voltage range to the drive voltage, so as to execute the bus current detection method as described in the first aspect and determine the current magnitude of the bus being measured.

[0015] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the first aspect and / or various possible implementations of the first aspect.

[0016] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the first aspect and / or various possible implementations of the first aspect.

[0017] The bus current detection method, apparatus, storage medium, and fluxgate Hall sensor provided in this application discretize the saturation time distribution of the fluxgate Hall coil by inserting an interference signal to disturb the flux change rate, thereby breaking the resonance relationship between the fixed frequency and the bus current fluctuation frequency. Specifically, the insertion of the interference signal changes the integral characteristics of the coil flux, making the saturation time no longer fixed, resulting in a random shift in the sampling window position. When the bus current fluctuation frequency is close to the original saturation frequency, the fixed sampling window may only cover the peak or trough, while the randomly shifted sampling window covers the peak, trough, and intermediate region, thus fully reflecting the fluctuation characteristics. Ultimately, this method avoids the sampling deviation problem caused by resonance and significantly improves the accuracy of the bus current average value calculation. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] Figure 1 A schematic diagram illustrating a scenario for the bus current detection method provided in this application;

[0020] Figure 2 A schematic flowchart illustrating the bus current detection method provided in this application embodiment;

[0021] Figure 3 This is a voltage diagram showing the voltage before and after the addition of the zero-voltage region, provided in an embodiment of this application.

[0022] Figure 4 This is a schematic diagram of the bus current detection device provided in the embodiments of this application.

[0023] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0024] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0025] In the fields of new energy vehicles and commercial vehicles, the remaining charge (SOC) of a battery system is a key parameter for ensuring safe vehicle operation and optimizing energy management. Currently, commercial vehicle battery systems commonly use high-precision fluxgate Hall sensors to sample the bus current in real time and calculate the SOC value using an integral algorithm.

[0026] The core working principle of a fluxgate Hall sensor is to apply an excitation voltage to a coil made of magnetic material (such as a high-rectangular-ratio permanent magnet), causing it to periodically saturate in both directions. In the unsaturated state, the coil senses the magnetic field generated by the bus current, and the magnitude of the bus current is calculated by detecting the magnetic field strength. Since the bus current may exhibit periodic fluctuations (such as a sinusoidal wave shape) during charging and discharging, if the fixed saturation frequency of the fluxgate Hall sensor matches the current fluctuation frequency, the sensor will only sample a portion of the sinusoidal wave period in the unsaturated phase (e.g., missing peaks or troughs), leading to a systematic deviation in the calculated average current value. This deviation directly causes distortion in the SOC calculation results, affecting the accuracy of the battery management system (BMS) decisions, and may even lead to safety hazards such as overcharging or over-discharging. Therefore, in the field of battery energy management, there is an urgent need for a method that can dynamically adjust the saturation frequency of the fluxgate Hall sensor to avoid the resonance effect between the sampling signal and the saturation frequency, thereby improving the current sampling accuracy and the reliability of SOC calculation.

[0027] To address the above technical problems, the inventors propose the following technical concept: by randomly adding a zero-voltage interval to the driving voltage, and removing the data corresponding to the zero-voltage interval when calculating the current magnitude of the bus.

[0028] Figure 1 This is a schematic diagram illustrating a scenario for the bus current detection method provided in this application. Figure 1 The scenario includes: a fluxgate Hall sensor 100 and a busbar under test 200.

[0029] The fluxgate Hall sensor 100 can be either an open-loop or closed-loop fluxgate Hall sensor.

[0030] The busbar under test 200 can be any type of wire being tested.

[0031] It is understood that the scenarios illustrated in the embodiments of this application do not constitute a specific limitation on the bus current detection method. In other feasible embodiments of this application, the above scenarios may include more or fewer components than illustrated, or combine some components, or split some components, or arrange different components, which can be determined according to the actual application scenario and are not limited here. Figure 1 The scenario shown can be implemented by hardware, software, or a combination of both.

[0032] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0033] Figure 2 This is a flowchart illustrating the bus current detection method provided in an embodiment of this application. The execution entity of this embodiment may be... Figure 1 The fluxgate Hall sensor 100 in this embodiment can also be a fluxgate Hall sensor; this embodiment does not impose any particular limitation on it. Figure 2 As shown, the method includes:

[0034] S201: In response to the detection of a current measurement command, a preset driving voltage is input to the excitation coil.

[0035] In this step, after receiving the current measurement command, the control circuit outputs an enable signal to the drive circuit. The drive circuit then outputs a DC voltage of fixed amplitude (100% duty cycle), which is applied to the two ends of the excitation coil through the designated MOS transistor conduction loop of the drive bridge arm. Based on the principle of electromagnetic induction, the fixed amplitude drive voltage satisfies the growth condition of magnetic flux "Φ=∫udt", providing a stable magnetic field excitation basis for the subsequent magnetization of the magnetic core to saturation. Here, Φ represents the magnetic flux, and u represents the drive voltage.

[0036] The current measurement command can be a detected start signal or a trigger signal received from the operator pressing the detection button.

[0037] S202: Add a zero-voltage interval to the driving voltage, where the zero-voltage interval corresponds to the start time of the saturation overcurrent point and a random end time.

[0038] In this step, the moment when the coil current reaches the saturation overcurrent point is determined as the starting moment. The control circuit generates irregular time parameters through an internal random number generator, and combines them with the timing period of the driving voltage to determine the termination moment of the zero voltage range. Then, at the starting moment, a turn-off command is sent to the driving circuit to control all the MOSFETs of the driving bridge arms to turn off simultaneously, so that the voltage across the excitation coil drops to 0V instantaneously, forming a zero voltage range. At the termination moment, a turn-on command is sent to the driving circuit to make the driving circuit input a DC voltage of a fixed amplitude to the excitation coil again.

[0039] S203: In response to reaching the termination time, the drive bridge arm of the excitation coil is flipped to reverse the voltage polarity of the excitation coil. The steps of adding the zero voltage range are repeated until the drive bridge arm of the excitation coil is flipped, until the detection is completed.

[0040] In this step, after the magnetic core saturates, the magnetic reluctance drops sharply. According to Ohm's law, the coil current will rapidly surge and exceed the overcurrent saturation threshold. Therefore, the overcurrent saturation threshold is preset to the critical value of the coil current when the magnetic core reaches saturation. After the control circuit detects that the current exceeds the threshold, it sends a bridge arm switching command to the drive circuit, causing the voltage polarity across the excitation coil to reverse. The step of adding the zero voltage range can be step S202 above, and the step of controlling the flipping of the drive bridge arm of the excitation coil can be this step and step S203. The essence of the repeated process is to use the voltage polarity reversal to drive the magnetic core to alternately saturate in the forward / reverse direction, accumulating magnetic field modulation information through multiple cycles until the preset detection cycle or data volume requirement is met.

[0041] S204: Obtain the voltage signal obtained from the amplifier circuit.

[0042] In this step, the Hall element is placed close to the magnetic core. When the magnetic field of the magnetic core changes, the charge carriers inside the Hall element are deflected under the action of the Lorentz force, forming a Hall voltage that is proportional to the magnetic field strength. The Hall voltage is amplified by the amplifier circuit to obtain a voltage signal. The control circuit receives the voltage signal through the signal acquisition module. The degree of waveform distortion (such as asymmetry of positive and negative half-cycles, even harmonics) directly reflects the modulation state of the magnetic core saturation.

[0043] S205: Determine the current magnitude of the busbar under test based on the voltage signal, start time, and end time.

[0044] In this step, the coil voltage is 0 in the zero voltage range, the magnetic flux growth stops, and the magnetic core magnetic field does not change effectively. The Hall voltage signal in the corresponding time period does not carry the bus current information. Therefore, by combining the start and end times, invalid signal segments can be located and the invalid new signal segments can be removed to obtain the remaining voltage signal. Then, the current of the bus under test is calculated based on the voltage signal.

[0045] As described in the above embodiments, this disclosure discretizes the saturation time distribution of the fluxgate Hall coil by inserting an interference signal to disturb the flux change rate, thereby breaking the resonance relationship between the fixed frequency and the bus current fluctuation frequency. Specifically, the insertion of the interference signal changes the integral characteristics of the coil flux, making the saturation time no longer fixed, resulting in a random shift in the sampling window position. When the bus current fluctuation frequency is close to the original saturation frequency, the fixed sampling window may only cover the peak or trough, while the randomly shifted sampling window covers the peak, trough, and intermediate region, thus fully reflecting the fluctuation characteristics. Ultimately, this method avoids the sampling deviation problem caused by resonance and significantly improves the accuracy of the bus current average value calculation.

[0046] In one possible implementation, step S205 above, determining the magnitude of the current in the bus under test based on the voltage signal, the start time, and the end time, includes:

[0047] S2051: Remove the voltage signal from the start time to the corresponding end time to obtain the remaining voltage signal.

[0048] In this step, the start and end times define the time range of zero voltage. During this period, the drive bridge arm is completely turned off, the magnetic flux of the magnetic core does not increase, and the voltage signal output by the Hall element contains only noise or fixed bias, and does not reflect the magnetic field modulation effect of the bus current. By comparing the timing, the data of this period is cut off from the original voltage signal, and the signal of the effective interval (non-zero voltage interval) is retained to ensure that the signals processed in subsequent steps all carry effective magnetic field information.

[0049] S2052: Determine the current magnitude of the busbar under test based on the residual voltage signal.

[0050] In this step, the residual voltage signal is the result of the magnetic field change transformation during the effective driving stage. The external magnetic field generated by the bus current will cause the magnetic core to saturate asymmetry, making the signal exhibit specific distortion characteristics. These characteristics are extracted by signal processing algorithms and matched with preset calibration relationships to quantify the magnetic field modulation information into current values. Essentially, it is the reverse conversion process of magnetic field-electrical signal-current.

[0051] As can be seen from the description of the above embodiments, the embodiments of this disclosure determine the current magnitude of the bus under test by removing the voltage signal from the start time to the corresponding end time and using the remaining voltage signal, thereby avoiding the impact of zero voltage interval data on the accuracy of data processing.

[0052] In one possible implementation, step S2052 above, determining the magnitude of the current in the bus under test based on the remaining voltage signal, includes:

[0053] S621: Determine the characteristic information of the remaining voltage signal.

[0054] In this step, the external magnetic field of the bus current will break the symmetry of the positive / reverse saturation of the magnetic core, causing distortion of the residual voltage signal. The main characteristic information includes even harmonic amplitude, positive and negative half-cycle amplitude difference, positive and negative saturation time difference, etc. The residual voltage signal is processed by algorithms such as filtering (removing high-frequency noise), Fourier transform (extracting harmonics), and time domain analysis (calculating time difference) to obtain the specific values ​​of these characteristics.

[0055] S622: Based on the feature information, find the preset correspondence between the feature information and the current magnitude to obtain the current magnitude of the bus under test.

[0056] In this step, the correspondence between feature information and current magnitude can be a mapping relationship calibrated in advance through experiments. The calibration process may include passing a standard current of known magnitude through the bus, recording the corresponding signal feature information, and storing the correspondence between the two as a calibration curve or database. In this step, the extracted feature information is substituted into the mapping relationship, and the bus current value corresponding to the feature is obtained by interpolation calculation or direct matching. The core is to utilize the fixed correspondence between feature quantity and current under the same driving conditions.

[0057] As can be seen from the description of the above embodiments, the embodiments of this disclosure extract quantitative features that are strongly correlated with the bus current through in-depth processing of the effective voltage signal, remove interference and noise, strengthen stable magnetic field modulation information, and use a preset calibration mapping relationship to accurately convert these feature information into specific values ​​of the bus current. This not only ensures the consistency and accuracy of the measurement across the entire current range from small to large, but also achieves the repeatability of the measurement results through standardized conversion logic, so that the abstract voltage signal is ultimately transformed into practical and reliable current measurement data.

[0058] In one possible implementation, step S202 above, which involves adding a zero-voltage interval to the driving voltage, includes:

[0059] S202A1: A zero-voltage interval is randomly added to the driving voltage during the overcurrent stage after the coil is saturated.

[0060] In this step, the overcurrent stage after coil saturation can include a stage where the coil current exceeds a preset saturation overcurrent threshold. A zero-voltage signal, representing a voltage value of zero, is used to temporarily interrupt the integration process of the coil current.

[0061] Figure 3 This is a voltage diagram showing the voltage before and after the addition of the zero-voltage region, provided in an embodiment of this application. Figure 3 As shown, a DC voltage with a 100% duty cycle is used before the zero voltage interval is added. After the zero voltage interval is inserted, no voltage is input during a certain time interval (the time interval corresponding to the zero voltage interval).

[0062] As described in the above embodiments, this disclosure interrupts the integration process of the coil current by inserting a zero-voltage signal during the overcurrent stage after the coil saturates. This step locally perturbs the rate of change of magnetic flux, providing a basis for the dynamic shift of the subsequent sampling window position.

[0063] In one possible implementation, step S202 above involves adding a zero-voltage interval to the driving voltage, including:

[0064] S202B1: Get the current time.

[0065] In this step, the current time can be determined by obtaining a timestamp or by the elapsed time since the current measurement command was detected.

[0066] S20B2: Obtain the coil current of the excitation coil.

[0067] In this step, a sampling resistor is connected in series in the series circuit of the excitation coil, or the coil current signal is coupled through a current sensor (such as a shunt or Hall current sensor) to convert the current signal into a measurable voltage signal; the control circuit obtains the real-time value of the coil current by real-time acquisition and analog-to-digital conversion of the voltage signal.

[0068] S202B3: Generate the start time based on the current coil current and the preset overcurrent saturation threshold.

[0069] In this step, the starting time can be determined as the current moment when the coil current reaches the overcurrent saturation threshold.

[0070] S202B4: Generate the termination time based on the start time and a random number.

[0071] In this step, a random number is used to determine the duration of the zero-voltage interval, and its value range is limited to a preset range (similarly, it can be within the range of 0 to 1, 0 to 0.5, etc.). The random number is multiplied by the preset duration threshold to obtain the duration. The start time is added to the duration to obtain the end time, so that the duration of the zero-voltage interval is randomized. At the same time, the duration is avoided from being too long, which would prevent the magnetic core from reaching saturation within the driving cycle, thus ensuring the continuity of the saturation cycle.

[0072] S202B5: Add a zero-voltage interval to the driving voltage based on the start and end times.

[0073] In this step, the control circuit sends timing control commands to the drive circuit according to the generated start and end times. When the start time arrives, the MOSFETs of all drive bridge arms are turned off, and the voltage across the coil drops to 0V. When the end time arrives, the control bridge arms are restored to their previous on state, and the original drive voltage is restored, thereby forming a zero-voltage interval for a specified time period in the drive voltage timing.

[0074] As can be seen from the description of the above embodiments, the embodiments of this disclosure achieve fully randomized control of zero-voltage insertion by combining the coil current of the excitation coil with the start and end times determined at the current time. This effectively avoids the risk of synchronization between the fixed saturation frequency and the bus current fluctuation frequency, avoids systematic deviations caused by missing sampling information, and ensures the cyclic continuity of the magnetic core's normal magnetization to saturation by reasonably constraining the interval duration. At the same time, it enhances the stability of the effective magnetic field modulation information in subsequent signal processing and ensures the accurate measurement of the bus current.

[0075] In one possible implementation, the difference between the termination time and the start time is less than a preset duration threshold.

[0076] The duration threshold can be preset by staff based on experimental data or empirical parameters.

[0077] As can be seen from the description of the above embodiments, the embodiments of this disclosure use a duration threshold to limit the difference between the termination time and the start time, so as to avoid the difference between the termination time and the start time being too large and affecting the measurement efficiency.

[0078] In one possible implementation, before randomly adding a zero-voltage interval to the driving voltage in step S202 above, the method further includes:

[0079] S220: The driving voltage of the excitation coil is controlled using a preset mode.

[0080] In this step, the preset mode provides stable initial driving parameters for the excitation coil, enabling the magnetic core to enter a predictable magnetization cycle. In this mode, the amplitude, frequency, and other parameters of the driving voltage are fixed, ensuring that the historical voltage signal output by the Hall element has a unified reference standard, providing a consistent signal source for subsequent historical current calculations.

[0081] Among them, the preset mode is, for example, a fixed 100% duty cycle, without adding a zero voltage range.

[0082] S221: Obtain the historical voltage signal of the amplifier circuit.

[0083] In this step, driven by a preset mode, the magnetic core is magnetized according to a fixed pattern. The Hall element captures the changes in the magnetic field of the magnetic core and outputs a voltage signal. The amplifier circuit amplifies the voltage signal of the Hall element. The control circuit collects and stores the amplified voltage signal to form historical voltage signal data, which includes the voltage measured under the preset mode.

[0084] S222: Determine the historical current of the bus under test based on the historical voltage signal.

[0085] In this step, the historical voltage signal also carries the modulation information of the bus current on the core saturation at a historical moment. Its processing logic is similar to that of step S2052 above. By extracting feature information and matching calibration relationships, the historical voltage signal is converted into the corresponding historical current value.

[0086] S223: If the historical current of the bus under test is less than the preset current threshold, then the above steps of inputting a preset voltage to the excitation coil are performed until the current of the bus under test is determined based on the voltage signal, the start time, and the end time.

[0087] In this step, the preset current threshold can be obtained through experimental testing. Based on the sensor's low-current measurement characteristics, the value corresponds to the critical current value at which the sensor is prone to systematic deviations under fixed excitation mode. The control circuit determines that the current bus current is in the low-current range when the historical current is less than the threshold, and initiates a dynamic saturation frequency measurement process that includes random zero-voltage insertion.

[0088] The step of inputting a preset voltage to the excitation coil is step S201 above, and the step of determining the current magnitude of the bus under test based on the voltage signal, the start time, and the end time is step S205 above.

[0089] As can be seen from the description of the above embodiments, the embodiments of this disclosure do not first add a zero-voltage interval to measure the bus current. When the current is large, the measurement result is used directly. If the historical current is not less than the threshold, it indicates that the bus current is strong. The fixed excitation mode can guarantee the measurement accuracy, and there is no need to perform this optimization process. This realizes the adaptive measurement strategy switching based on the current magnitude and ensures the measurement reliability under different current intervals.

[0090] Figure 4 This is a schematic diagram of the bus current detection device provided in an embodiment of this application. Figure 4 As shown, the bus current detection device 400 includes: a voltage input module 401, a voltage input module 402, a voltage reversal module 403, a signal acquisition module 404, and a current determination module 405.

[0091] The voltage input module 401 is used to input a preset driving voltage to the excitation coil in response to the detection of a current measurement command.

[0092] The voltage input module 402 is used to add a zero voltage interval to the driving voltage, wherein the zero voltage interval corresponds to a fixed start time and a random end time of the saturation overcurrent point.

[0093] The voltage reversal module 403 is used to control the drive bridge arm of the excitation coil to reverse in response to the arrival of the termination time, so as to reverse the voltage polarity of the excitation coil, and repeat the steps of adding the zero voltage range to control the drive bridge arm of the excitation coil to reverse until the detection is completed.

[0094] The signal acquisition module 404 is used to acquire the voltage signal obtained by the amplifier circuit.

[0095] The current determination module 405 is used to determine the magnitude of the current of the bus under test based on the voltage signal, the start time, and the end time.

[0096] The apparatus provided in this embodiment can be used to execute the technical solutions of the above method embodiments. Its implementation principle and technical effects are similar, and will not be described again here.

[0097] In one possible implementation, the current determination module 405 is used to remove the voltage signal from the start time to the corresponding end time to obtain the remaining voltage signal; and to determine the current magnitude of the bus under test based on the remaining voltage signal.

[0098] In one possible implementation, the current determination module 405 is used to determine the characteristic information of the remaining voltage signal; based on the characteristic information, it searches for a preset correspondence between the characteristic information and the current magnitude to obtain the current magnitude of the bus under test.

[0099] In one possible implementation, the voltage application module 402 is used to randomly apply a zero-voltage interval to the drive voltage during the overcurrent phase after the coil saturates.

[0100] In one possible implementation, the voltage input module 402 is used to obtain the current time; obtain the coil current of the excitation coil; generate the start time based on the current time, the coil current and the preset overcurrent saturation threshold; and generate the end time based on the start time and a random number.

[0101] A zero-voltage interval is added to the driving voltage based on the start and end times.

[0102] In one possible implementation, the difference between the termination time and the start time is less than a preset duration threshold.

[0103] In one possible implementation, the bus current detection device 400 further includes a historical current determination module 406.

[0104] The historical current determination module 406 is used to control the driving voltage of the excitation coil using a preset mode; acquire the historical voltage signal of the Hall element; determine the historical current of the bus under test based on the historical voltage signal; if the historical current of the bus under test is less than a preset current threshold, then the steps of inputting a preset voltage to the excitation coil and determining the current of the bus under test based on the voltage signal, the start time and the end time are executed.

[0105] The apparatus provided in this embodiment can be used to execute the technical solutions of the above method embodiments. Its implementation principle and technical effects are similar, and will not be described again here.

[0106] This application also provides a fluxgate Hall sensor. The fluxgate Hall sensor includes: a control circuit, a drive circuit, an excitation coil, a soft magnetic core, and a Hall element. The control circuit controls the drive circuit to input a drive voltage to the excitation coil and adds a zero-voltage interval to the drive voltage to execute the bus current detection method provided in any of the above embodiments, thereby determining the magnitude of the current in the bus being measured.

[0107] The control circuit can consist of a microcontroller (MCU / MPU), an ADC sampling module, a random number generator, a clock module, a memory unit (ROM / RAM), a comparator, and I / O interface circuits. The drive circuit mainly consists of a full-bridge drive arm (four high-voltage MOSFETs), a drive chip, sampling resistors, overcurrent protection circuitry, and a power conversion module. The excitation coil is constructed by winding highly conductive enameled copper wire (such as copper enameled wire) onto a soft magnetic core. The soft magnetic core can be made of a soft magnetic material with high permeability and low coercivity (such as permalloy or nanocrystalline alloy). The Hall element can consist of a Hall chip (including a semiconductor Hall plate and signal conditioning circuitry), a package, and pins.

[0108] The functions described above in this document can be performed at least in part by one or more hardware logic components. For example, exemplary types of hardware logic components that can be used, without limitation, include: field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip (SoCs), complex programmable logic devices (CPLDs), and so on.

[0109] This application also provides a computer-readable storage medium storing computer-executable instructions. When a processor executes the computer-executable instructions, it implements the technical solution of the bus current detection method in any of the above embodiments. The implementation principle and beneficial effects are similar to those of the bus current detection method, and can be found in the implementation principle and beneficial effects of the bus current detection method, which will not be repeated here.

[0110] In the context of this application, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. Machine-readable media can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0111] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the technical solution of the bus current detection method in any of the above embodiments. Its implementation principle and beneficial effects are similar to those of the bus current detection method, and can be found in the implementation principle and beneficial effects of the bus current detection method, which will not be repeated here.

[0112] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

[0113] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0114] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A method for detecting bus current, characterized in that, include: In response to the detection of a current measurement command, a preset driving voltage is input to the excitation coil; A zero-voltage interval is added to the driving voltage, wherein the zero-voltage interval corresponds to a fixed start time and a random end time of the saturation overcurrent point; In response to reaching the termination time, the drive bridge arm of the excitation coil is controlled to flip, so that the voltage polarity of the excitation coil is reversed. The steps of adding the zero voltage range are repeated until the step of controlling the drive bridge arm of the excitation coil to flip is completed. Obtain the voltage signal from the amplifier circuit; The magnitude of the current in the busbar under test is determined based on the voltage signal, the start time, and the end time.

2. The method according to claim 1, characterized in that, Determining the current magnitude of the busbar under test based on the voltage signal, the start time, and the end time includes: Remove the voltage signal from the start time to the corresponding end time to obtain the remaining voltage signal; The magnitude of the current in the busbar under test is determined based on the remaining voltage signal.

3. The method according to claim 2, characterized in that, Determining the magnitude of the current in the bus under test based on the remaining voltage signal includes: Determine the characteristic information of the remaining voltage signal; Based on the feature information, a preset correspondence between the feature information and the current magnitude is found to obtain the current magnitude of the busbar under test.

4. The method according to claim 1, characterized in that, Adding a zero-voltage range to the driving voltage includes: A zero-voltage interval is randomly added to the driving voltage during the overcurrent stage after the coil saturates.

5. The method according to claim 1, characterized in that, Adding a zero-voltage range to the driving voltage includes: Get the current time; Obtain the coil current of the excitation coil; The starting time is generated based on the current time, the coil current, and the preset overcurrent saturation threshold. The termination time is generated based on the start time and the random number. Based on the start time and the end time, the zero voltage range is added to the driving voltage.

6. The method according to claim 1, characterized in that, The difference between the termination time and the start time is less than a preset duration threshold.

7. The method according to any one of claims 1 to 6, characterized in that, Before adding the zero-voltage range to the driving voltage, the following is also included: The driving voltage of the excitation coil is controlled using a preset mode; Obtain the historical voltage signal of the amplifier circuit; Based on the historical voltage signal, determine the historical current of the busbar under test; If the historical current of the bus under test is less than a preset current threshold, then the steps of inputting a preset voltage to the excitation coil and determining the current magnitude of the bus under test based on the voltage signal, the start time, and the end time are executed.

8. A busbar current detection device, characterized in that, include: The voltage input module is used to input a preset driving voltage to the excitation coil in response to the detection of a current measurement command; A voltage input module is used to input a zero voltage interval into the driving voltage, wherein the zero voltage interval corresponds to a fixed start time and a random end time of the saturation overcurrent point. A voltage reversal module is used to control the drive bridge arm of the excitation coil to reverse in response to reaching the termination time, so as to reverse the voltage polarity of the excitation coil, and repeat the step of adding the zero voltage range to the step of controlling the drive bridge arm of the excitation coil to reverse until the detection is completed; The signal acquisition module is used to acquire the voltage signal obtained from the amplifier circuit. The current determination module is used to determine the magnitude of the current of the bus under test based on the voltage signal, the start time, and the end time.

9. A fluxgate Hall effect sensor, characterized in that, include: Control circuit, drive circuit, excitation coil, soft magnetic core and Hall element; The control circuit is used to control the drive circuit to input a drive voltage to the excitation coil and to add a zero voltage range to the drive voltage, so as to perform the bus current detection method as described in any one of claims 1 to 6 and determine the current magnitude of the bus under test.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1 to 6.

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