Current measurement method and circuit breaker

Abstract

The invention provides a current measurement method and a circuit breaker, and relates to the technical field of low-voltage apparatuses. A plurality of magnetic sensors in the circuit breaker are sequentially arranged along the width direction of a copper bar body, and in an arrangement path formed by the plurality of magnetic sensors, a first end sensor is arranged close to a first side edge of the copper bar body along the length direction, and a second end sensor is arranged close to a second side edge of the copper bar body along the length direction. The method comprises the following steps: acquiring a total target voltage corresponding to a plurality of magnetic sensors when a first target current flows through a copper bar through an analog-to-digital converter; and calculating the first target current according to the total target voltage, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage and the total calibration voltage, so that the first target current can be determined according to the superposition of the sampling results of the plurality of magnetic sensors, and a relatively accurate current measurement result can be obtained. The mechanical stability and electrical performance of the copper bar are ensured, and the performance and service life of the circuit breaker are ensured.

Description

Technical Field

[0001] The present application relates to the technical field of low-voltage electrical appliances, and in particular to a current measurement method and a circuit breaker. Background Art

[0002] A magnetic sensor is a device used to measure current. It indirectly measures the current value by detecting the magnetic field generated by the current without direct contact with the circuit. It has the characteristics of good isolation, high safety, and fast response. It is widely used in power systems, industrial control, new energy and other fields.

[0003] In the prior art, when magnetic sensors are applied to busbars in circuit breakers for current measurement, since the magnetic sensors do not contain a magnetic core, in order to improve the sensor's detection sensitivity to magnetic fields, the busbar needs to be structurally designed to focus the current, forcing the current to concentrate in a specific area, thereby increasing the current density in that area. The increase in current density will lead to a stronger magnetic field, thereby improving the sensitivity of the magnetic sensor.

[0004] However, the existing method of increasing the current density through current focusing design to improve the magnetic field strength will increase the power consumption in specific areas due to the current concentration in these specific areas, causing the temperature of the copper busbar to rise, and the temperature increase will affect the mechanical stability and electrical performance of the copper busbar. Summary of the Invention

[0005] The purpose of this application is to provide a current measurement method and a circuit breaker to address the deficiencies in the above-mentioned prior art, which can ensure the mechanical stability and electrical performance of the copper busbar body.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows: In a first aspect, the present invention provides a current measurement method, which is applied to a controller in a circuit breaker, the circuit breaker comprising the controller and a copper busbar; the controller comprising an analog-to-digital converter, the copper busbar comprising a copper busbar body and a plurality of magnetic sensors, each of the magnetic sensors being connected to a sampling port of the analog-to-digital converter via a first signal processing module, wherein the plurality of magnetic sensors are disposed on the copper busbar body, the plurality of magnetic sensors being arranged in sequence along the width direction of the copper busbar body, and the arrangement path formed by the plurality of magnetic sensors having a first end sensor disposed proximate to a first side edge of the copper busbar body along the length direction, and a second end sensor disposed proximate to a second side edge of the copper busbar body along the length direction, the method comprising: Acquiring, by an analog-to-digital converter, a total target voltage corresponding to the plurality of magnetic sensors when a first target current flows through the copper busbar; A first target current flowing through the copper busbar is calculated based on the total target voltage, the total target sensitivity of the multiple magnetic sensors corresponding to the total target voltage, and the total calibration voltage, wherein the total calibration voltage is the total voltage corresponding to the multiple magnetic sensors when the calibration current flows through the copper busbar.

[0007] In an optional embodiment, the number of the magnetic sensors is determined according to the width of the copper busbar body and the width of the sensor sensitive area of ​​the magnetic sensor perpendicular to the current direction, and the sensor sensitive area is the area of ​​the magnetic sensor that responds to magnetic field changes in accordance with preset requirements.

[0008] In an optional embodiment, the plurality of magnetic sensors are axially symmetrically distributed along a center line in a width direction of the copper busbar body.

[0009] In an optional embodiment, the analog-to-digital converter includes a plurality of sampling ports, and each of the first signal processing modules includes: a first operational amplifier, a first resistor, and a second resistor; One end of the first resistor is electrically connected to the output end of the magnetic sensor, and the other end is electrically connected to one end of the second resistor and the non-inverting input end of the first operational amplifier, and the other end of the second resistor is grounded; The inverting input terminal of the first operational amplifier is electrically connected to the output terminal of the first operational amplifier and each sampling port of the analog-to-digital converter.

[0010] In an optional embodiment, before calculating the first target current flowing through the copper busbar based on the total target voltage and the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, the method further includes: Obtaining the total sensitivity and total voltage range of multiple magnetic sensors corresponding to multiple calibrated current ranges; Acquire a preset sensitivity mapping relationship according to the total sensitivities and total voltage ranges corresponding to the multiple calibrated current ranges of the multiple magnetic sensors, wherein the preset sensitivity mapping relationship includes: the total sensitivities corresponding to the multiple total voltage ranges; The total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage is determined according to the preset sensitivity mapping relationship.

[0011] In an optional embodiment, obtaining the total sensitivity of the plurality of magnetic sensors corresponding to the plurality of calibration current ranges includes: According to the calibration current and the reference current of each magnetic sensor in each calibration current range, respectively obtaining a calibration voltage corresponding to each magnetic sensor when the copper busbar flows through the calibration current, and a sub-reference voltage corresponding to each magnetic sensor when the copper busbar flows through the reference current; Calculating the sensitivity of each magnetic sensor corresponding to each calibration current range according to the calibration current, the reference current, the calibration voltage, and the sub-reference voltage; The total sensitivity of the plurality of magnetic sensors is calculated based on the sensitivity of each magnetic sensor in each calibration current range.

[0012] In an optional embodiment, obtaining the total voltage range of the plurality of magnetic sensors corresponding to the plurality of calibrated current ranges includes: Calculating a first total reference voltage according to the first sub-reference voltages corresponding to the magnetic sensors; calculating a second total reference voltage according to the second sub-reference voltages corresponding to the magnetic sensors; The total voltage range of the plurality of magnetic sensors corresponding to each calibration current range is calculated according to the first total reference voltage and the second total reference voltage.

[0013] In an optional embodiment, the first signal processing module includes: a plurality of second operational amplifiers, an adder, and an attenuation circuit, each of the magnetic sensors is electrically connected to an input of the adder through each second signal processing module, an output of the adder is electrically connected to an input of the attenuation circuit, and an output of the attenuation circuit is electrically connected to a sampling port of the analog-to-digital converter; Calculating a first target current flowing through the copper busbar according to the total target voltage, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, and the total calibration voltage includes: A first target current flowing through the copper bus is calculated based on the total target voltage, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, the feedback resistor and the input resistor corresponding to the adder, the attenuation coefficient corresponding to the attenuation circuit, and the total calibration voltage.

[0014] In an optional embodiment, after obtaining the total target voltage corresponding to the plurality of magnetic sensors when the copper busbar flows through the first target current through the analog-to-digital converter, the method further includes: A first target current flowing through the copper busbar is calculated based on the total target voltage and a preset fitting polynomial, wherein the preset fitting polynomial includes a plurality of fitting coefficients, each of which is obtained by fitting the total voltage and the plurality of preset currents corresponding to the plurality of preset currents flowing through the copper busbar.

[0015] In a second aspect, the present invention provides a circuit breaker, comprising a controller and a copper busbar, the controller comprising an analog-to-digital converter, the copper busbar comprising a copper busbar body and a plurality of magnetic sensors, each of the magnetic sensors being connected to a sampling port of the analog-to-digital converter via a first signal processing module, wherein the plurality of magnetic sensors are disposed on the copper busbar body, the plurality of magnetic sensors being arranged sequentially along the width direction of the copper busbar body, and wherein a first end sensor in an arrangement path formed by the plurality of magnetic sensors is disposed proximate to a first side edge of the copper busbar body along the length direction, and a second end sensor is disposed proximate to a second side edge of the copper busbar body along the length direction; The controller is used to execute the steps of the current measurement method as described in any of the aforementioned embodiments.

[0016] The beneficial effects of this application are: In the current measurement method and circuit breaker provided in the embodiment of the present application, the method is applied to a controller in the circuit breaker, the circuit breaker includes a controller and a copper busbar; the controller includes an analog-to-digital converter, the copper busbar includes a copper busbar body and a plurality of magnetic sensors, each magnetic sensor is connected to the sampling port of the analog-to-digital converter through a first signal processing module, wherein the plurality of magnetic sensors are arranged on the copper busbar body, the plurality of magnetic sensors are arranged in sequence along the width direction of the copper busbar body, and in the arrangement path composed of the plurality of magnetic sensors, the first end sensor is arranged close to the first side of the copper busbar body along the length direction, and the second end sensor is arranged close to the second side of the copper busbar body along the length direction. The method includes: obtaining, through the analog-to-digital converter, a total target voltage corresponding to the plurality of magnetic sensors when a first target current flows through the copper busbar ; According to the total target voltage, the total target sensitivity of multiple magnetic sensors corresponding to the total target voltage, and the total calibration voltage, the first target current flowing through the copper busbar is calculated, so that the total target voltage can be determined by superimposing the sampling results of multiple magnetic sensors, and then the first target current is calculated based on this. A more comprehensive current measurement result can be obtained, and the measurement error caused by the position deviation of a single magnetic sensor or the uneven distribution of local current can be reduced. It can more comprehensively reflect the current distribution of the entire copper busbar and improve the accuracy of the measurement results. Compared with the existing current measurement method, it is achieved that there is no need to set a current focusing structure on the copper busbar, which can avoid the structural strength, power consumption and temperature rise problems caused by the current focusing structure, ensure the mechanical stability and electrical performance of the copper busbar, and thus ensure the performance and life of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A schematic diagram of the structure of a copper busbar in the prior art provided in an embodiment of the present application; Figure 2 A schematic diagram of the structure of a copper busbar provided in an embodiment of the present application; Figure 3 A schematic diagram of a flow chart of a current measurement method provided in an embodiment of the present application; Figure 4 A schematic structural diagram of another copper busbar provided in an embodiment of the present application; Figure 5 A schematic diagram of a current measurement circuit provided in an embodiment of the present application; Figure 6 A schematic flow chart of another current measurement method provided in an embodiment of the present application; Figure 7 A schematic flow chart of another current measurement method provided in an embodiment of the present application; Figure 8 A schematic diagram of a current measurement circuit provided in an embodiment of the present application; Figure 9 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0019] Explanation of the main component symbols: 101-first signal processing module; 103-adder; 104-attenuation circuit; 110-copper busbar body; IC1-first operational amplifier; IC2-second operational amplifier; IC3-third operational amplifier; IC4-fourth operational amplifier; R1-first resistor; R2-second resistor; R7-seventh resistor; R8-eighth resistor; R9-ninth resistor; R10-tenth resistor; R11-eleventh resistor; R12-twelfth resistor; R13-thirteenth resistor; R14-fourteenth resistor; Sensor1-first magnetic sensor; Sensor2-second magnetic sensor; Sensor3-third magnetic sensor. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition or explanation in subsequent drawings.

[0023] A current sensor is a key device within a circuit breaker. In the field of low-voltage electrical equipment, it converts current signals into measurable electrical signals (such as voltage or digital signals). This is primarily used for real-time monitoring and control of circuit current and certain protective actions. It utilizes various physical principles (such as Ohm's law, electromagnetic induction, and the Hall effect) to achieve non-invasive or invasive measurement, making it a key component in power electronics, industrial automation, new energy, and other fields.

[0024] In related technologies, magnetic sensors are often used to measure the current of copper bars in circuit breakers. Magnetic sensors integrate magnetic sensitive elements (such as anisotropic magnetoresistive AMR or giant magnetoresistive GMR, Hall sensor) with signal processing circuits on a single chip, and output digital or analog signals by detecting the changes in the magnetic field generated by the current.

[0025] In addition, magnetic sensors can significantly reduce power loss while providing electrical isolation. These characteristics are particularly important for high voltage and high current applications, because electrical isolation ensures protection against contact, while low power consumption ensures low self-heating. Furthermore, magnetic sensors are coreless. Even in the case of overcurrent caused by a short circuit, core saturation and subsequent residual magnetism will not occur, avoiding hysteresis in the transmission characteristics.

[0026] However, since magnetic sensors don't contain a magnetic core, a current-concentrating busbar design is necessary to improve the sensor's sensitivity to magnetic field detection. This current-concentrating design involves slotting or reshaping the copper busbar, forcing the current to concentrate in a specific area, thereby increasing the current density in that area. This increased current density leads to a stronger magnetic field, which in turn increases the sensitivity of the magnetic sensor.

[0027] Common current-concentrating designs in related technologies include various structural shapes, such as straight, S-bend, and vertical insertion. Straight sensing structures have lower insertion resistance but are more sensitive to crosstalk. S-bend sensing structures reduce crosstalk by rotating the sensor, but have higher insertion resistance. Vertical insertion sensing structures are suitable for high-current systems and achieve better isolation performance by slotting the busbar.

[0028] Figure 1 A schematic diagram of the structure of a copper busbar in the prior art provided in the embodiment of the present application is shown as follows: Figure 1 As shown, the copper busbar can be set as an S-bend sensing structure to realize a current focusing structure, and a magnetic sensor can be set at the S-bend sensing structure to measure the current flowing through the copper busbar.

[0029] Combine Figure 1 As can be seen, existing current concentrating designs often require slotting or reshaping the busbar copper busbar, which weakens the copper busbar's mechanical strength. For example, the copper busbar's thickness is reduced at the slotted area, making it more susceptible to deformation or fracture under mechanical stresses (such as vibration and thermal expansion). Furthermore, in applications with high vibration or thermal expansion, the copper busbar's mechanical stability may be affected, thereby compromising the reliability of the entire system.

[0030] The current-concentrating design increases magnetic field strength by increasing current density, which leads to uneven current distribution in the copper busbar. Current is concentrated in specific areas, increasing power consumption in those areas. This localized increase in power consumption can cause the copper busbar to heat up, impacting the system's thermal stability and efficiency. Furthermore, the increased current density exacerbates skin and eddy current effects, further increasing temperature rise. This temperature rise can degrade the copper busbar's mechanical properties and increase thermal expansion and contraction, affecting its mechanical stability and electrical performance, ultimately impacting the circuit breaker's performance and lifespan.

[0031] Furthermore, the current converging design changes the geometry of the copper busbar, increasing the length and complexity of the current path, thereby increasing the impedance of the copper busbar. Higher impedance will lead to greater voltage drop, increase system power consumption, and may affect the accuracy of current measurement.

[0032] In view of this, an embodiment of the present application provides a current measurement method, which can ensure the current measurement accuracy while avoiding the structural strength, power consumption and temperature rise problems caused by the current focusing structure, and ensure the mechanical stability and electrical performance of the copper busbar.

[0033] Figure 2 This is a schematic diagram of the structure of a copper busbar provided in an embodiment of the present application. Figure 3This is a flow chart of a current measurement method provided in an embodiment of the present application. The current measurement method can be applied to a controller in a circuit breaker, which may include a controller and a copper busbar. The controller includes an analog-to-digital converter (ADC), and the copper busbar includes a copper busbar body 110 and multiple magnetic sensors, each of which is connected to a sampling port of the ADC via a first signal processing module. It should be noted that the present application does not limit the configuration between the controller and the ADC. In some embodiments, the ADC may also be configured independently of the controller.

[0034] Among them, such as Figure 2 As shown, two magnetic sensors are used for illustration. Multiple magnetic sensors are arranged in sequence along the width direction of the copper busbar body 110. In the arrangement path composed of the multiple magnetic sensors, the first end sensor (i.e., the first magnetic sensor Sensor1) is arranged close to the first side edge of the copper busbar body 110 along the length direction, and the second end sensor (i.e., the second magnetic sensor Sensor2) is arranged close to the second side edge of the copper busbar body 110 along the length direction, and the first side edge and the second side edge are parallel. The copper busbar body 110 can be a rectangular structure, and the arrow in the figure can indicate the direction of current.

[0035] Based on this setting structure, on the one hand, by setting up multiple magnetic sensors, different areas of the copper busbar can be covered, effectively reducing measurement errors caused by position deviation of a single sensor or uneven local current distribution. On the other hand, considering that the rectangular copper busbar body 110 has stronger electric field concentration and leakage due to sharp edges, the current density is highest and the magnetic field is more concentrated at the corners. Therefore, by setting the first end sensor and the second end sensor close to the side of the copper busbar body 110 in the length direction, it can be ensured as much as possible that the magnetic sensors can receive the magnetic field to the greatest extent, thereby improving measurement accuracy and reducing measurement errors.

[0036] Alternatively, as Figure 2 As shown, the method includes: S101. Obtain, through an analog-to-digital converter, a total target voltage corresponding to multiple magnetic sensors when a first target current flows through the copper busbar.

[0037] Among them, the sampling port of the analog-to-digital converter, that is, the ADC sampling port, each magnetic sensor can be connected to the ADC sampling port of the analog-to-digital converter through the first signal processing module. It can be understood that the controller can obtain the sub-target voltage corresponding to each magnetic sensor when the copper bus passes through the first target current through the ADC sampling port of the analog-to-digital converter, and sum the sub-target voltages corresponding to each magnetic sensor to calculate the total target voltage corresponding to multiple magnetic sensors when the copper bus passes through the first target current.

[0038] S102 : Calculate a first target current flowing through the copper busbar according to the total target voltage, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, and the total calibration voltage.

[0039] The total calibration voltage is the total voltage corresponding to the multiple magnetic sensors when the calibration current flows through the copper busbar. Optionally, the total calibration voltage can be obtained through an analog-to-digital converter as described above, and the calibration current can be 0, but is not limited to this.

[0040] The sensitivity of a magnetic sensor can represent the minimum current change that the magnetic sensor can detect under steady-state operating conditions. The total target sensitivity of multiple magnetic sensors corresponding to the total target voltage can represent the total minimum current change that the multiple magnetic sensors can detect based on the total target voltage.

[0041] In some embodiments, based on the linearity performance of multiple magnetic sensors, if the linearity performance of multiple magnetic sensors is good (for example, the sub-voltage collected by each magnetic sensor is linearly related to the current flowing through the copper bus), different total target voltages can correspond to the same total target sensitivity. Alternatively, if the linearity performance of multiple magnetic sensors is poor, different total target voltages can correspond to different total target sensitivities. This is not limited here.

[0042] Optionally, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage may be determined by pre-calibration.

[0043] Among them, during the specific calculation, the target voltage difference between the total target voltage and the total calibration voltage can be calculated. According to the target voltage difference, the product of the total target sensitivity and the signal resolution of the analog-to-digital converter, the first target current flowing through the copper busbar can be calculated. The total target voltage can be determined by superimposing the sampling results of multiple magnetic sensors, and then the first target current is calculated based on this. A more comprehensive current measurement result can be obtained, and the measurement error caused by the position deviation of a single magnetic sensor or the uneven distribution of local current can be reduced. The current distribution of the entire copper busbar can be more comprehensively reflected, and the accuracy of the measurement results can be improved. Compared with the existing current measurement method, there is no need to set a current focusing structure on the copper busbar, which can avoid the structural strength, power consumption and temperature rise problems caused by the current focusing structure, ensure the mechanical stability and electrical performance of the copper busbar, and thus ensure the performance and life of the circuit breaker.

[0044] In summary, an embodiment of the present application provides a current measurement method, which is applied to a controller in a circuit breaker, wherein the circuit breaker includes a controller and a copper busbar; the controller includes an analog-to-digital converter, and the copper busbar includes a copper busbar body and multiple magnetic sensors, each magnetic sensor being connected to a sampling port of the analog-to-digital converter via a first signal processing module, wherein the multiple magnetic sensors are disposed on the copper busbar body, the multiple magnetic sensors are arranged sequentially along the width direction of the copper busbar body, and in an arrangement path composed of the multiple magnetic sensors, a first end sensor is disposed proximate to a first side edge of the copper busbar body along the length direction, and a second end sensor is disposed proximate to a second side edge of the copper busbar body along the length direction. The method includes: obtaining, through the analog-to-digital converter, a total target voltage corresponding to the multiple magnetic sensors when a first target current flows through the copper busbar; The first target current flowing through the copper busbar is calculated based on the total target voltage, the total target sensitivity of multiple magnetic sensors corresponding to the total target voltage, and the total calibration voltage. This makes it possible to determine the total target voltage based on the superposition of the sampling results of multiple magnetic sensors, and then calculate the first target current based on this. This can obtain a more comprehensive current measurement result, and can also reduce measurement errors caused by the position deviation of a single magnetic sensor or uneven local current distribution. It can more comprehensively reflect the current distribution of the entire copper busbar and improve the accuracy of the measurement results. Compared with the existing current measurement method, it is no longer necessary to set a current focusing structure on the copper busbar, which can avoid the structural strength, power consumption and temperature rise problems caused by the current focusing structure, ensure the mechanical stability and electrical performance of the copper busbar, and thus ensure the performance and life of the circuit breaker.

[0045] Figure 4 A schematic diagram of another copper busbar structure provided in an embodiment of the present application. In an optional embodiment, the number of magnetic sensors is determined by the width of the copper busbar body and the width of the sensor sensitive area of ​​the magnetic sensor perpendicular to the direction of current flow. The sensor sensitive area is the area of ​​the magnetic sensor that responds to magnetic field changes in accordance with preset requirements.

[0046] Optionally, the sensor sensitive area may be an area where the magnetic signal collected by the magnetic sensor is the largest.

[0047] Among them, one end of the copper busbar along the length direction is used to connect the incoming line terminal, and the other end is used to connect the load. Figure 4 As shown, let the width of the copper busbar body 110 be D, the width of the sensor sensitive area perpendicular to the current direction in the magnetic sensor be d, and the number of magnetic sensors be N. The relationship between the three can be expressed as: N≤ D / d, where the value of N is greater than 2.

[0048] It should be noted that the present application does not limit the shapes of the magnetic sensor and the sensor sensitive area. In some embodiments, the shape of the magnetic sensor and the sensor sensitive area may be rectangular, but is not limited thereto.

[0049] In an optional embodiment, the plurality of magnetic sensors are axially symmetrically distributed along a center line in the width direction of the copper busbar body 110 .

[0050] Reference Figure 4 As shown, if three magnetic sensors are provided on the copper busbar body 110 , the three magnetic sensors may be axially symmetrically distributed along the center line in the width direction of the copper busbar body 110 , that is, the three magnetic sensors are axially symmetrically distributed about the third magnetic sensor Sensor3 .

[0051] In some implementations, to facilitate calculation, the property parameters (eg, size, shape, etc.) of the multiple magnetic sensors may be the same.

[0052] The application of the embodiments of the present application can not only solve the problems of increased copper bus impedance, increased temperature rise and structural deterioration caused by the use of a current-gathering structure in the copper bus, but also, by arranging multiple magnetic sensors to be axially symmetrically distributed along the center line in the width direction of the copper bus body 110, uniform sampling can be achieved and measurement accuracy can be improved. The use of multiple magnetic sensors increases the redundancy of the system. Even if a sensor fails, the system can still continue to work, thereby improving reliability.

[0053] Figure 5 A schematic diagram of a current measurement circuit provided in an embodiment of the present application. Optionally, if the number of available sampling ports of the analog-to-digital converter is greater than or equal to the number of magnetic sensors, in some embodiments, each first signal processing module 101 includes: a first operational amplifier IC1, a first resistor R1, and a second resistor R2; wherein one end of the first resistor R1 is electrically connected to the output of the magnetic sensor, the other end is electrically connected to one end of the second resistor R2 and the non-inverting input of the first operational amplifier IC1, and the other end of the second resistor R2 is grounded; the inverting input of the first operational amplifier IC1 is electrically connected to the output of the first operational amplifier IC1 and each sampling port of the analog-to-digital converter.

[0054] The number of sampling ports of the analog-to-digital converter may be the same as the number of magnetic sensors. If so, each magnetic sensor may be electrically connected to each sampling port of the analog-to-digital converter via each first signal processing module 101 .

[0055] like Figure 5As shown, in some embodiments, three magnetic sensors can be set on the copper bus body 110, wherein the first magnetic sensor Sensor1 can be electrically connected to the first sampling port ADC1 of the analog-to-digital converter through the first signal processing module 101, the second magnetic sensor Sensor2 can be electrically connected to the first sampling port ADC2 of the analog-to-digital converter through the first signal processing module 101, and the third magnetic sensor Sensor3 can be electrically connected to the third sampling port ADC3 of the analog-to-digital converter through the first signal processing module 101.

[0056] It should be noted that in the embodiment of the present application, the output of the magnetic sensor is a single-ended signal, but in practice the output of the magnetic sensor may be a differential signal. Accordingly, the first signal processing module 101 should select a differential follower or a differential operational amplifier for processing.

[0057] By applying the embodiments of the present application, it is possible to transmit the voltages (i.e., V1, V2, and V3) collected by each magnetic sensor to the output end as distortion-free as possible through the setting of the first signal processing module 101, that is, the voltages VO1, VO2, and VO3 at the output end are approximately equal to V1, V2, and V3, respectively, and the voltage at the output end is isolated and matched with the impedance of the subsequent circuit, thereby preventing the sensor output voltage from being affected by the subsequent circuit and improving stability.

[0058] Figure 6 A flow chart of another current measurement method provided in an embodiment of the present application. In an optional embodiment, as Figure 6 As shown, before calculating the first target current flowing through the copper busbar based on the total target voltage and the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, the method further includes: S201 : Obtain the total sensitivity and total voltage range of multiple magnetic sensors corresponding to multiple calibrated current ranges.

[0059] In some embodiments, considering the poor linearity of multiple magnetic sensors, the current range that can be measured by the multiple magnetic sensors can be divided into multiple calibrated current ranges. For example, the current range that can be measured by the multiple magnetic sensors is 0-100A. Optionally, it can be divided into the following three calibrated current ranges: 0-30A, 30-70A, and 70-100A, where each calibrated current range can include multiple preset calibration currents.

[0060] For each calibrated current range, the total sensitivity and total voltage range of the multiple magnetic sensors can be calculated. The total voltage range can be obtained using an analog-to-digital converter (ADC) as described above. Specifically, the ADC can be used to obtain the total target voltages of the multiple magnetic sensors when the copper busbar flows through multiple calibrated currents in each calibrated current range.

[0061] S202 : Acquire a preset sensitivity mapping relationship according to total sensitivities and total voltage ranges corresponding to multiple calibrated current ranges of multiple magnetic sensors.

[0062] The preset sensitivity mapping relationship includes: total sensitivities corresponding to multiple total voltage ranges. After obtaining the total sensitivities and total voltage ranges corresponding to multiple calibration current ranges of multiple magnetic sensors, the preset sensitivity mapping relationship corresponding to the multiple calibration current ranges can be constructed accordingly.

[0063] For example, the total sensitivity corresponding to the first calibrated current range of 0-30 A can be K1, and the corresponding total voltage measurement range can be VM1-VM2; the total sensitivity corresponding to the second calibrated current range of 30-70 A can be K2, and the corresponding total voltage measurement range can be VM2-VM3; and the total sensitivity corresponding to the third calibrated current range of 70-100 A can be K3, and the corresponding total voltage measurement range can be VM3-VM4. Of course, the specific mapping relationship is not limited to this.

[0064] S203 : Determine the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage according to a preset sensitivity mapping relationship.

[0065] Among them, after obtaining the preset sensitivity mapping relationship, the total target voltage range corresponding to the total target voltage can be determined in multiple total voltage ranges by searching the preset sensitivity mapping relationship, and the total target sensitivity can be determined according to the total sensitivity corresponding to the total target voltage range.

[0066] For example, if the total target voltage corresponding to multiple magnetic sensors when the copper busbar flows through the first target current is obtained by an analog-to-digital converter according to the aforementioned method, Vs1, wherein the total voltage measurement range corresponding to Vs1 is determined to be VM2-VM3 through comparison, wherein VM2<Vs1≤VM3, then according to the preset sensitivity mapping relationship, the total sensitivity corresponding to the total target voltage Vs1 can be further determined to be K2.

[0067] It should be noted that, in some implementations, the preset sensitivity mapping relationship can be stored in a non-volatile memory of the controller, such as a flash memory (Flash), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), etc., which is not limited here.

[0068] By applying the embodiments of the present application, it is possible to obtain a preset sensitivity mapping relationship through a segmented calibration method, eliminate the error of the sensitivity coefficient under different calibration currents and poor sensor linearity, and improve the current measurement accuracy within the full measurement range. This makes the method provided by the present application applicable to application scenarios where the linearity of the magnetic sensor is poor, and can improve the applicability of the method of the present application.

[0069] Figure 7 A flow chart of another current measurement method provided in an embodiment of the present application. In an optional embodiment, as Figure 7 As shown, the above-mentioned method of obtaining the total sensitivity of multiple magnetic sensors corresponding to multiple calibration current ranges includes: S301. According to the calibration current and reference current of each magnetic sensor in each calibration current range, obtain the calibration voltage corresponding to each magnetic sensor when the copper busbar flows through the calibration current and the sub-reference voltage corresponding to each magnetic sensor when the copper busbar flows through the reference current.

[0070] Optionally, the calibration current in each calibration current range may be zero current, and the reference current in each calibration current range may be the maximum current corresponding to each calibration current range. Of course, the specific setting method is not limited to this.

[0071] In some embodiments, referring to the aforementioned method, the calibration voltage corresponding to each magnetic sensor when the calibration current flows through the copper busbar is obtained through an analog-to-digital converter, and the sub-reference voltage corresponding to each magnetic sensor when the reference current flows through the copper busbar is obtained through an analog-to-digital converter.

[0072] S302 : Calculate the sensitivity of each magnetic sensor corresponding to each calibration current range according to the calibration current, the reference current, the calibration voltage, and the sub-reference voltage.

[0073] Optionally, during the specific calculation, the reference voltage difference between the sub-reference voltage and the calibration voltage can be calculated, and the calibration current difference between the reference current and the calibration current can be calculated. Based on the ratio of the reference voltage difference and the calibration current difference, the sensitivity of each magnetic sensor corresponding to each calibration current range can be calculated and determined.

[0074] In some implementations, the sensitivity of each magnetic sensor at each calibration current range may be calculated with reference to the following formula: Ki=(Vi_ref2-Vi_offset1) / (Iref2-Iref1) Wherein, i represents the serial number of the magnetic sensor, which is an integer from 1 to N, N represents the total number of magnetic sensors, and N≥2; Iref1 represents the calibration current; Iref2 represents the reference current; Vi_offset1 represents the calibration voltage corresponding to the i-th magnetic sensor when the calibration current Iref1 flows through the copper busbar; Vi_ref2 represents the sub-reference voltage corresponding to the i-th magnetic sensor when the reference current Iref2 flows through the copper busbar. It should be noted that the calibration current Iref1 can be 0.

[0075] S303 , calculating the total sensitivity of the plurality of magnetic sensors according to the sensitivity of each magnetic sensor in each calibration current range.

[0076] Optionally, the total sensitivity corresponding to the plurality of magnetic sensors may be determined according to the sum of the sensitivities corresponding to the respective calibrated current ranges of the magnetic sensors.

[0077] For example, if an application scenario includes: a first magnetic sensor Sensor1, a second magnetic sensor Sensor2, and a third magnetic sensor Sensor3, where the sensitivity of the first magnetic sensor Sensor1 corresponding to a certain calibrated current range is K1, the sensitivity of the second magnetic sensor Sensor2 corresponding to the calibrated current range is K2, and the sensitivity of the third magnetic sensor Sensor3 corresponding to the calibrated current range is K3, then the total sensitivity Ktotal of multiple magnetic sensors corresponding to the calibrated current range can be expressed as: Ktotal = K1 + K2 + K3.

[0078] It should be noted that in some embodiments, if the linearity of multiple magnetic sensors meets preset requirements (good), the total sensitivity of the multiple magnetic sensors can also be determined based on the average total sensitivity Ktotal of the multiple magnetic sensors corresponding to multiple calibration current ranges. Optionally, the specific calculation can refer to the following formula:

[0079] Wherein, j represents the serial number of the calibration current range, N represents the number of calibration current ranges, i represents the serial number of the magnetic sensor, and M represents the number of magnetic sensors.

[0080] For example, in some scenarios, three calibration current ranges can be set, wherein the three calibration current ranges can be 0-30A, 0-60A and 0-90A respectively, then the value of N is 3, and the values ​​of j are 1, 2 and 3. Indicates the sensitivity of the first magnetic sensor in the first calibrated current range. Indicates the sensitivity of the first magnetic sensor in the second calibration current range. Indicates the sensitivity of the first magnetic sensor in the third calibrated current range. It represents the sensitivity of the second magnetic sensor corresponding to the first calibrated current range, and so on, which will not be repeated here.

[0081] In an optional embodiment, the step of obtaining the total voltage range of the plurality of magnetic sensors corresponding to the plurality of calibrated current ranges includes: A first total reference voltage is calculated based on the first sub-reference voltage corresponding to each magnetic sensor; a second total reference voltage is calculated based on the second sub-reference voltage corresponding to each magnetic sensor; and a total voltage range corresponding to each calibrated current range of the multiple magnetic sensors is calculated based on the first total reference voltage and the second total reference voltage.

[0082] The total voltage range corresponding to each calibration current range of the plurality of magnetic sensors may be determined based on the first total reference voltage and the second total reference voltage corresponding to each calibration current range of the plurality of magnetic sensors.

[0083] Optionally, the first total reference voltage can be determined based on the sum of the first sub-reference voltages corresponding to the magnetic sensors when the copper bus passes a first reference current, and the second total reference voltage can be determined based on the sum of the second sub-reference voltages corresponding to the magnetic sensors when the copper bus passes a second reference current.

[0084] For example, when a first reference current flows through the copper busbar, the calibration voltages corresponding to the three magnetic sensors are V1_ref1, V2_ref1, and V3_ref1, respectively. The first total reference voltage Vsum_ref1 can be expressed as: Vsum_ref1 = V1_ref1 + V2_ref1 + V3_ref1. The calculation method for the second total reference voltage Vsum_ref2 can be found in the same formula as for the first total reference voltage and is not further described here. Furthermore, the total voltage range corresponding to the multiple magnetic sensors at a calibration current range can be expressed as: Vsum_ref1 - Vsum_ref2.

[0085] By applying the embodiments of the present application, a relatively accurate preset sensitivity mapping relationship can be obtained when the linearity of the magnetic sensor is poor, thereby improving the applicability of the method of the present application.

[0086] In an optional embodiment, after obtaining the total target voltage corresponding to the plurality of magnetic sensors when the copper busbar flows through the first target current through the analog-to-digital converter, the method further includes: A first target current flowing through the copper busbar is calculated based on the total target voltage and a preset fitting polynomial, wherein the preset fitting polynomial includes a plurality of fitting coefficients, each fitting coefficient being obtained by fitting the total voltage and the plurality of preset currents corresponding to the plurality of preset currents flowing through the copper busbar.

[0087] In some embodiments, the first target current flowing through the copper busbar can also be calculated using a preset fitting polynomial. The preset fitting polynomial can be obtained by fitting the relationship between the total voltage corresponding to a plurality of preset currents flowing through the copper busbar and the plurality of preset currents. Optionally, the preset fitting polynomial includes a plurality of fitting coefficients, which can be determined using a least squares method.

[0088] Optionally, the multiple preset currents can be: 0A, 1A, 2A, 3A, ..., 100A, a total of 101, and the total voltage corresponding to each preset current can be Vtotal0, Vtotal1, Vtotal2, Vtotal3, ..., Vtotal100, respectively. Curve fitting can be performed based on the multiple preset currents and multiple total voltages to calculate a polynomial fitting formula.

[0089] Optionally, the preset fitting polynomial may be expressed as:

[0090] in, It indicates the total target voltage corresponding to multiple magnetic sensors when the copper busbar flows through the first target current. Indicates the first target current flowing through the copper busbar, 、 as well as They are respectively the coefficients of the quadratic term, the linear term, and the constant term in the preset fitting polynomial.

[0091] It should be noted that when performing specific calculations, the calculation method can be determined based on the computing power of the controller and the current measurement accuracy. Optionally, if the computing power of the controller is sufficient and the accuracy of the controller is high, a preset fitting polynomial can be used for calculation. Otherwise, the aforementioned method can be used to calculate the first target current flowing through the copper busbar based on the total target voltage, the total target sensitivity of multiple magnetic sensors corresponding to the total target voltage, and the total calibration voltage. This application does not limit this and can be flexibly selected according to the actual application scenario.

[0092] In an optional embodiment, if the number of magnetic sensors is greater than the number of available sampling ports in the analog-to-digital converter, for example, the number of magnetic sensors includes multiple and the number of available sampling ports in the analog-to-digital converter is 1, then the above-mentioned first signal processing module may include: multiple second operational amplifiers IC2, adders, adder 103 and attenuation circuit 104, each magnetic sensor is electrically connected to the input end of the adder 103 through each second operational amplifier IC2, the output end of the adder 103 is electrically connected to the input end of the attenuation circuit 104, and the output end of the attenuation circuit 104 is electrically connected to the sampling port of the analog-to-digital converter.

[0093] Figure 8 This is a schematic diagram of a current measurement circuit provided in an embodiment of the present application. Figure 8 As shown, in some embodiments, if the number of available sampling ports of the analog-to-digital converter is limited, and only one fourth sampling port ADC4 is available, it can be seen that the number of available sampling ports is less than the number of magnetic sensors. In this case, each magnetic sensor can be electrically connected to the sampling port of the analog-to-digital converter via each second operational amplifier IC2, the adder 103, and the attenuation circuit 104.

[0094] like Figure 8 As shown, the output of each magnetic sensor can be electrically connected to the non-inverting input of its corresponding second operational amplifier IC2 , and the inverting input of each second operational amplifier IC2 is electrically connected to the output of the second operational amplifier IC2 and the input of the adder 103 .

[0095] Optionally, the adder 103 may include: a third operational amplifier IC3, a matching resistor, a tenth resistor R10, an eleventh resistor R11, and a twelfth resistor R12, wherein the number of the matching resistors is determined according to the number of the magnetic sensors, such as Figure 8 As shown, when there are three magnetic sensors, the matching resistors may include: a seventh resistor R7, an eighth resistor R8, and a ninth resistor R9. The twelfth resistor R12 and the twelfth resistor R12 may be regarded as the feedback resistor and input resistor corresponding to the adder 103.

[0096] One end of the seventh resistor R7, the eighth resistor R8, and the ninth resistor R9 can be electrically connected to the output terminal of the second operational amplifier IC2 corresponding to the first magnetic sensor Sensor1, the second magnetic sensor Sensor2, and the third magnetic sensor Sensor3, respectively. The other ends of the seventh resistor R7, the eighth resistor R8, and the ninth resistor R9 are electrically connected to one end of the tenth resistor R10 and the inverting input terminal of the third operational amplifier IC3. The other end of the tenth resistor R10 is grounded. One end of the eleventh resistor R11 is grounded. The other end of the eleventh resistor R11 is electrically connected to one end of the twelfth resistor R12 and the non-inverting input terminal of the third operational amplifier IC3. The other end of the twelfth resistor R12 is electrically connected to the output terminal of the third operational amplifier IC3 and the input terminal of the attenuation circuit 104.

[0097] Optionally, the attenuation circuit 104 may include: a fourth operational amplifier IC4, a thirteenth resistor R13, and a fourteenth resistor R14. Figure 8 As shown, one end of the thirteenth resistor R13 can be electrically connected to the output end of the third operational amplifier IC3, the other end can be electrically connected to one end of the fourteenth resistor R14 and the inverting input end of the fourth operational amplifier IC4, the other end of the fourteenth resistor R14 is grounded, and the non-inverting input end of the fourth operational amplifier IC4 is electrically connected to the output end of the fourth operational amplifier IC4 and the fourth sampling port ADC4 of the analog-to-digital converter.

[0098] based on Figure 8 As shown in the circuit diagram, the calculation of the first target current flowing through the copper busbar based on the total target voltage, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, and the total calibration voltage includes: A first target current flowing through the copper bus is calculated based on the total target voltage, the total target sensitivity of the multiple magnetic sensors corresponding to the total target voltage, the feedback resistor and input resistor corresponding to the adder, the attenuation coefficient corresponding to the attenuation circuit, and the total calibration voltage.

[0099] The specific calculation can refer to the following calculation formula. For the adder 103, the signal output by the adder 103 can be expressed as: Vtotal_add=(R12 / R7)*(Va1+Va2+Va3), wherein Vtotal_add represents the voltage after the adder 103 superimposes and fuses the voltage, Va1 represents the output voltage of the second operational amplifier IC2 corresponding to the first magnetic sensor Sensor1, Va2 represents the output voltage of the second operational amplifier IC2 corresponding to the second magnetic sensor Sensor2, and Va3 represents the output voltage of the second operational amplifier IC2 corresponding to the third magnetic sensor Sensor3. In addition, for Figure 8It should be noted that in the circuit diagram shown, the seventh resistor R7, the eighth resistor R8, the ninth resistor R9 and the tenth resistor R10 have the same resistance value and can be regarded as a parallel relationship.

[0100] For attenuation circuit 104, see Figure 8 As shown in the circuit diagram, the attenuation coefficient Ks of the attenuation circuit 104 can be expressed as Ks=R14 / (R13+R14).

[0101] Furthermore, the signal Vadc_in attenuated by the attenuation circuit 104 and input to the analog-to-digital converter can be calculated as: Vadc_in=Vtotal_add*Ks=(R12 / R7)*(Va1+Va2+Va3)*Ks.

[0102] In some implementations, assuming that the reference sampling voltage of the analog-to-digital converter is Vref, the sampling resolution of the analog-to-digital converter is n bits, the value converted by the analog-to-digital converter is: Value_adc=(Vadc_in / Vref)*(2^n), where Vadc_in represents the input voltage of the analog-to-digital converter.

[0103] Then, combined with the total target sensitivity Ktotal of multiple magnetic sensors corresponding to the total target voltage, the first target current Itotal flowing through the copper busbar can be calculated. The specific calculation formula is: Itotal =(Value_adc-Voffset_adc) / (2^n)*Vref / Ktotal Wherein, Value_adc represents the ADC sampling value after the analog-to-digital converter converts the input voltage Vadc_in. Voffset_adc represents the total ADC sampling value corresponding to multiple magnetic sensors when the calibration current flows through the copper busbar, that is, the ADC sampling value of the offset voltage signal when the current flowing through the copper busbar is zero. n represents the sampling resolution of the analog-to-digital converter, Vref represents the reference sampling voltage of the analog-to-digital converter, and Ktotal represents the total target sensitivity of multiple magnetic sensors corresponding to the total target voltage.

[0104] By applying the embodiments of the present application, the voltages collected by multiple magnetic sensors are respectively voltage-followed by the second operational amplifiers, so that the output of the magnetic sensor can be isolated and matched with the impedance of the subsequent circuit; further, the voltages output by the second operational amplifiers can be superimposed by an adder, wherein, if the amplitude of the signal is too high after superposition, the amplitude can be attenuated by an attenuation current, and finally the signal output by the attenuation circuit is input to the ADC for collection and calculation, so that the method provided by the embodiments of the present application can be applicable to situations where the analog-to-digital converter has fewer sampling ports, which can improve the applicability of the method of the present application.

[0105] Optionally, the present invention also provides a circuit breaker, comprising a controller and a copper busbar, the controller comprising an analog-to-digital converter, the copper busbar comprising a copper busbar body and a plurality of magnetic sensors, each magnetic sensor being connected to a sampling port of the analog-to-digital converter through a first signal processing module, wherein the plurality of magnetic sensors are arranged on the copper busbar body, the plurality of magnetic sensors are arranged in sequence along the width direction of the copper busbar body, and in an arrangement path composed of the plurality of magnetic sensors, the first end sensor is arranged close to the first side edge of the copper busbar body along the length direction, and the second end sensor is arranged close to the second side edge of the copper busbar body along the length direction; the controller is used to perform the steps of the current measurement method in any of the aforementioned embodiments.

[0106] By applying the embodiments of the present application, it is possible to determine the total target voltage based on the superposition of the sampling results of multiple magnetic sensors, and then calculate the first target current based on this, so as to obtain a more comprehensive current measurement result, and reduce the measurement error caused by the position deviation of a single magnetic sensor or the uneven distribution of local current. It can more comprehensively reflect the current distribution of the entire copper busbar and improve the accuracy of the measurement results. Compared with the existing current measurement method, it is possible to avoid the need to set a current focusing structure on the copper busbar, and avoid the structural strength, power consumption and temperature rise problems caused by the current focusing structure, thereby ensuring the mechanical stability and electrical performance of the copper busbar, and thus ensuring the performance and life of the circuit breaker.

[0107] It should be noted that the specific working process and technical effects of the controller in the circuit breaker are the same as those of the corresponding method embodiment described above. For the sake of brief description, some parts are not mentioned in this embodiment, and reference may be made to the corresponding contents in the method embodiment.

[0108] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application, which can be integrated into the above-mentioned circuit breaker. Figure 9 As shown, the electronic device may include: a processor 210, a storage medium 220, and a bus 230. The storage medium 220 stores machine-readable instructions executable by the processor 210. When the electronic device is running, the processor 210 and the storage medium 220 communicate via the bus 230, and the processor 210 executes the machine-readable instructions to perform the steps of the above-mentioned method embodiment. The specific implementation methods and technical effects are similar and will not be repeated here.

[0109] Optionally, the present application further provides a storage medium storing a computer program, which, when executed by a processor, executes the steps of the above method embodiment. The specific implementation and technical effects are similar and will not be described in detail here.

[0110] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0111] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0112] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0113] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) or a processor (English: processor) to perform some steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: USB flash drives, mobile hard drives, read-only memory (English: Read-Only Memory, abbreviated: ROM), random access memory (English: Random Access Memory, abbreviated: RAM), magnetic disks or optical disks, and other media that can store program code.

[0114] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element. The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application. It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A current measurement method, characterized in that: A controller for a circuit breaker, the circuit breaker comprising the controller and a copper busbar; the controller comprising an analog-to-digital converter, the copper busbar comprising a copper busbar body and a plurality of magnetic sensors, each of the magnetic sensors being connected to a sampling port of the analog-to-digital converter via a first signal processing module, wherein the plurality of magnetic sensors are disposed on the copper busbar body, the plurality of magnetic sensors being sequentially arranged along the width direction of the copper busbar body, and a first end sensor in an arrangement path formed by the plurality of magnetic sensors being disposed proximate to a first side edge of the copper busbar body along the length direction, and a second end sensor being disposed proximate to a second side edge of the copper busbar body along the length direction, the method comprising: Acquiring, by an analog-to-digital converter, a total target voltage corresponding to the plurality of magnetic sensors when a first target current flows through the copper busbar; A first target current flowing through the copper busbar is calculated based on the total target voltage, the total target sensitivity of the multiple magnetic sensors corresponding to the total target voltage, and the total calibration voltage, wherein the total calibration voltage is the total voltage corresponding to the multiple magnetic sensors when the calibration current flows through the copper busbar.

2. The method according to claim 1, characterized in that The number of the magnetic sensors is determined according to the width of the copper busbar body and the width of the sensor sensitive area perpendicular to the current direction in the magnetic sensor. The sensor sensitive area is the area in the magnetic sensor that responds to magnetic field changes in accordance with preset requirements.

3. The method according to claim 1, characterized in that The plurality of magnetic sensors are axially symmetrically distributed along a center line in a width direction of the copper busbar body.

4. The method according to claim 1, wherein The analog-to-digital converter includes a plurality of sampling ports, and each of the first signal processing modules includes: a first operational amplifier, a first resistor, and a second resistor; One end of the first resistor is electrically connected to the output end of the magnetic sensor, and the other end is electrically connected to one end of the second resistor and the non-inverting input end of the first operational amplifier, and the other end of the second resistor is grounded; The inverting input terminal of the first operational amplifier is electrically connected to the output terminal of the first operational amplifier and each sampling port of the analog-to-digital converter.

5. The method according to claim 1, wherein Before calculating the first target current flowing through the copper busbar based on the total target voltage and the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, the method further includes: Obtaining the total sensitivity and total voltage range of multiple magnetic sensors corresponding to multiple calibrated current ranges; Acquire a preset sensitivity mapping relationship according to the total sensitivities and total voltage ranges corresponding to the multiple calibrated current ranges of the multiple magnetic sensors, wherein the preset sensitivity mapping relationship includes: the total sensitivities corresponding to the multiple total voltage ranges; The total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage is determined according to the preset sensitivity mapping relationship.

6. The method according to claim 5, characterized in that The obtaining of the total sensitivity of the plurality of magnetic sensors corresponding to the plurality of calibration current ranges includes: According to the calibration current and the reference current of each magnetic sensor in each calibration current range, respectively obtaining a calibration voltage corresponding to each magnetic sensor when the copper busbar flows through the calibration current, and a sub-reference voltage corresponding to each magnetic sensor when the copper busbar flows through the reference current; Calculating the sensitivity of each magnetic sensor corresponding to each calibration current range according to the calibration current, the reference current, the calibration voltage, and the sub-reference voltage; The total sensitivity of the plurality of magnetic sensors is calculated based on the sensitivity of each magnetic sensor in each calibration current range.

7. The method according to claim 6, characterized in that The obtaining of the total voltage range of the plurality of magnetic sensors corresponding to the plurality of calibrated current ranges includes: Calculating a first total reference voltage according to the first sub-reference voltages corresponding to the magnetic sensors; calculating a second total reference voltage according to the second sub-reference voltages corresponding to the magnetic sensors; The total voltage range of the plurality of magnetic sensors corresponding to each calibration current range is calculated according to the first total reference voltage and the second total reference voltage.

8. The method according to claim 1, characterized in that The first signal processing module includes: a plurality of second operational amplifiers, an adder, and an attenuation circuit, each of the magnetic sensors is electrically connected to an input of the adder via a second operational amplifier, an output of the adder is electrically connected to an input of the attenuation circuit, and an output of the attenuation circuit is electrically connected to a sampling port of the analog-to-digital converter; Calculating a first target current flowing through the copper busbar according to the total target voltage, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, and the total calibration voltage includes: A first target current flowing through the copper bus is calculated based on the total target voltage, the total target sensitivity of the plurality of magnetic sensors corresponding to the total target voltage, the feedback resistor and the input resistor corresponding to the adder, the attenuation coefficient corresponding to the attenuation circuit, and the total calibration voltage.

9. The method according to any one of claims 1 to 8, characterized in that After obtaining the total target voltage corresponding to the plurality of magnetic sensors when the copper busbar flows through the first target current through the analog-to-digital converter, the method further includes: A first target current flowing through the copper busbar is calculated based on the total target voltage and a preset fitting polynomial, wherein the preset fitting polynomial includes a plurality of fitting coefficients, each of which is obtained by fitting the total voltage and the plurality of preset currents corresponding to the plurality of preset currents flowing through the copper busbar.

10. A circuit breaker, characterized in that: The circuit breaker includes a controller and a copper busbar, the controller includes an analog-to-digital converter, the copper busbar includes a copper busbar body and a plurality of magnetic sensors, each of the magnetic sensors is connected to a sampling port of the analog-to-digital converter via a first signal processing module, wherein the plurality of magnetic sensors are disposed on the copper busbar body, the plurality of magnetic sensors are sequentially arranged along the width direction of the copper busbar body, and in an arrangement path formed by the plurality of magnetic sensors, a first end sensor is disposed proximate to a first side edge of the copper busbar body along the length direction, and a second end sensor is disposed proximate to a second side edge of the copper busbar body along the length direction; The controller is configured to execute the steps of the current measurement method according to any one of claims 1 to 9.

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