Hall sensor and shunt fused redundant current detection system and method

Abstract

According to the Hall sensor and shunt fused redundant current detection system and method provided by the invention, the Hall sensor and the shunt are fused, so that a heterogeneous current measurement framework is formed on the premise of not increasing the size of a current measurement device; compared with a current measurement mode formed by a single Hall sensor or a single shunt, the method has higher safety, and the common cause failure problem of sensors of the same principle is effectively avoided by using sensors of different measurement principles and data transmission paths, so that hardware has higher detection and diagnosis coverage rate; in addition, CAN communication is used in signal interaction, a low-voltage area and a high-voltage area are effectively isolated in hardware design, and CAN communication is located in the low-voltage area, so that the whole system has good insulativity; the Hall sensor is small in size and low in sensitivity to stray magnetic fields, the problem of high machining difficulty is solved, hardware cost is effectively reduced, and current detection accuracy is improved.

Description

Technical Field

[0001] The present invention relates to the field of current measurement, and in particular to a redundant current detection system and method integrating a Hall sensor and a shunt. Background Art

[0002] The current sensor is a device used to measure the magnitude of the current. The current sensors used in the existing passenger vehicle battery packs can be divided into different types according to their working principles, such as shunt sensors, fluxgate sensors and Hall sensors. Among them, the shunt sensor has the characteristics of low cost, high precision and high linearity, and is widely used in the current measurement scenario of automotive batteries. At present, the current measurement requirements for automotive batteries are not lower than the ASILC level. For this reason, it is necessary to design the current sensor redundantly at the hardware level (such as homogeneous current measurement architecture and heterogeneous current measurement architecture), which will lead to the current sensor being too large and seriously wasting space. In addition, the homogeneous current measurement architecture has the disadvantages of high cost of low-voltage / high-voltage insulation isolation and wiring harness insulation processing, high power loss, and high cost of analog-to-digital conversion channels; while the heterogeneous current measurement architecture has the disadvantages of large size, relatively low space utilization, susceptibility to stray magnetic field interference and high overall cost. It can be seen that the existing redundant design current sensors generally have the problems of being too large and common cause failure, and cannot provide stable and accurate current detection for automotive batteries. Summary of the invention

[0003] The object of the present invention is to provide a redundant current detection system and method integrating a Hall sensor and a shunt, which integrates the Hall sensor and the shunt to form a heterogeneous current measurement framework without increasing the volume of the current measurement device. Compared with the current measurement method formed by a single Hall sensor or a single shunt, the redundant current detection system and method have higher safety, and effectively avoid the common cause failure problem of sensors with the same principle by using sensors and data transmission paths with different measurement principles, so that the hardware has a higher detection and diagnosis coverage rate; in addition, CAN communication is used in signal interaction, and the low-voltage area is effectively isolated from the high-voltage area in hardware design, and the CAN communication is in the low-voltage area, so that the whole system has good insulation; and the Hall sensor is small in size, and its sensitivity to stray magnetic fields is low, and the problem of high processing difficulty is overcome, thereby effectively reducing hardware costs and improving current detection accuracy.

[0004] The present invention is achieved through the following technical solutions:

[0005] The redundant current detection system of the Hall sensor and the shunt is composed of:

[0006] A first precision resistor is arranged in series on a loop formed by connecting the battery and the load;

[0007] A second precision resistor, connected in parallel with the first precision resistor;

[0008] an analog front-end module, connected to the first precision resistor, for measuring a voltage drop across the first precision resistor;

[0009] The analog front-end module is also connected to the data processing unit via the isolation communication module, so as to transmit the voltage drop to the data processing unit;

[0010] The data processing unit is used to calculate the first current on the first precision resistor according to the voltage drop;

[0011] a digital isolation Hall sensor connected in series with the second precision resistor and used for measuring a second current on the second precision resistor;

[0012] The data processing unit is also connected to the data isolation Hall sensor, and is used to measure the first current, the second current, the first precision resistor and the second precision resistor's respective resistance values, determine the credibility of the current data, diagnose whether the redundant current detection system has a hardware failure, and output the final measured current value.

[0013] Optionally, the digital isolation Hall sensor and the isolation communication module isolate the high voltage area and the low voltage area of ​​the redundant current detection system.

[0014] Optionally, the data processing unit is connected to the digital isolation Hall sensor via SPI and / or IIC, so as to obtain the second current measured by the digital isolation Hall sensor.

[0015] Optionally, the data processing unit is connected to the digital isolation Hall sensor via SPI and IIC, so as to obtain the second current measured by the digital isolation Hall sensor, including:

[0016] Step S1, the data processing unit simultaneously starts to obtain the second current measured by the digital isolation Hall sensor through SPI and IIC, and uses the following formula (1) to control the SPI and IIC of the data processing unit to be divided into a master-slave transmission scheme according to the change of the second current obtained multiple times,

[0017]

[0018] In the above formula (1), F represents the control value of the SPI and IIC of the data processing unit divided into the master-slave transmission scheme; I2(a+1) represents the second current value obtained for the a+1th time; I2(a) represents the second current value obtained for the ath time; I2(n) represents the second current value obtained for the nth time; I2(1) represents the second current value obtained for the 1st time; I0 represents the preset current threshold; n represents the total number of second currents obtained by a single transmission channel; It means that the maximum value of I2(a+1)-I2(a) is obtained under the condition of 1≤a≤n; && means AND operation. If both sides are true, the overall output value is 1, otherwise, the overall output value is 0;

[0019] If F=1, the transmission scheme of the data processing unit is that SPI is the main transmission and IIC is the backup transmission scheme;

[0020] If F=0, the transmission scheme of the data processing unit is that IIC is the main transmission and SPI is the backup transmission scheme;

[0021] Step S2, using the following formula (2), compare the data received under the primary and backup transmission schemes to control whether the backup transmission scheme is closed.

[0022]

[0023] In the above formula (2), B represents the control value of whether the backup transmission scheme is turned off; G_IIC 16 (k) indicates the kth data received under the IIC transmission channel; G_SPI 16 (k) represents the kth data received under the SPI transmission channel; m represents the total number of data obtained by a single transmission channel; F[], F{} both represent judgment functions. If the formula in the brackets is true, the function value of the judgment function is 1, otherwise, the function value of the judgment function is 0;

[0024] If B=1, the backup transmission scheme is controlled to be closed;

[0025] If B=0, the control standby transmission scheme is not closed;

[0026] Step S3: If the backup transmission scheme is not closed, the following formula (3) is used to control whether to merge the backup transmission scheme with the main transmission scheme to transmit data according to the amount of data received each time.

[0027]

[0028] In the above formula (3), H represents the control value of whether to merge and transmit data; S0 represents the preset data volume threshold; len[] represents the data volume of the data in the brackets;

[0029] If H=1, the backup transmission scheme is controlled and combined with the main transmission scheme to transmit data;

[0030] If H=0, the backup transmission scheme and the main transmission scheme are combined to transmit data without any control.

[0031] Optionally, the first precision resistor, the second precision resistor, the analog front-end module, the isolated communication module, the digital isolation Hall sensor, and the data processing unit are all arranged on the same PCB board.

[0032] The redundant current detection method of the Hall sensor and the shunt fusion includes:

[0033] Step S1, measuring the voltage drop across the first precision resistor by the analog front-end module; calculating the first current on the first precision resistor according to the resistance value of the first precision resistor and the voltage drop by the data processing unit;

[0034] Step S2, measuring a second current on the second precision resistor by using the digital isolation Hall sensor, and acquiring the second current from the digital isolation Hall sensor by using the data processing unit;

[0035] Step S3, determining the corresponding total current according to the first current and the second current; determining the Hall proportional total current and the precision resistor total current according to the resistance values ​​of the first precision resistor and the second precision resistor;

[0036] Step S4, judging the credibility of the current data according to the total current, the Hall proportional total current and the precision resistor total current, diagnosing whether the redundant current detection system has a hardware failure, and outputting the final measured current value.

[0037] Optionally, before step S1, the method further includes:

[0038] According to the rated current information of the analog front-end module and the digital isolation Hall sensor, the resistance values ​​of the first precision resistor and the second precision resistor are adjusted.

[0039] Optionally, in step S3, determining a corresponding total current according to the first current and the second current includes:

[0040] Performing filtering processing on the first current and the second current by the data processing unit, and then adding the first current and the second current to obtain the total current;

[0041] or,

[0042] In the step S3, determining the Hall proportional total current and the precision resistor total current according to the resistance values ​​of the first precision resistor and the second precision resistor respectively includes:

[0043] According to the resistance ratio between the first precision resistor and the second precision resistor, the Hall proportional total current and the precision resistor total current are determined; wherein the Hall proportional total current refers to the total current value calculated based on the second current measured by the digital isolation Hogg sensor; the precision resistor total current refers to the total current value calculated based on the first current calculated by the data processing unit.

[0044] Optionally, in step S4, judging the credibility of current data according to the total current, the Hall ratio total current and the precision resistor total current, diagnosing whether a hardware failure occurs in the redundant current detection system, and outputting a final measured current value, includes:

[0045] According to the difference between any two of the total current, the Hall proportional total current and the precision resistor total current, the credibility of the current data is judged, whether the analog front-end module and the digital isolation Hall sensor have hardware failures is diagnosed, and the final measured current value is output.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] The redundant current detection system and method of the Hall sensor and shunt provided in the present application integrate the Hall sensor and the shunt to form a heterogeneous current measurement framework without increasing the volume of the current measurement device. Compared with the current measurement method formed by a single Hall sensor or a single shunt, it has higher security, and effectively avoids the common cause failure problem of sensors with the same principle by using sensors and data transmission paths with different measurement principles, so that the hardware has a higher detection and diagnosis coverage rate; in addition, CAN communication is used in signal interaction, and the low-voltage area is effectively isolated from the high-voltage area in hardware design. The CAN communication is in the low-voltage area, so that the entire system has good insulation; and the Hall sensor is small in size, and its sensitivity to stray magnetic fields is low, and the problem of high processing difficulty is overcome, effectively reducing hardware costs and improving current detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0049] Figure 1 A schematic diagram of the structure of a redundant current detection system integrating a Hall sensor and a shunt provided by the present invention.

[0050] Figure 2 A schematic flow chart of a redundant current detection method combining a Hall sensor and a shunt provided by the present invention.

[0051] Figure numerals: 1. battery; 2. load; 3. first precision resistor; 4. second precision resistor; 5. analog front-end module; 6. isolated communication module; 7. data processing unit; 8. digital isolation Hall sensor. DETAILED DESCRIPTION

[0052] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It is to be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some structures related to the present application are shown in the accompanying drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0053] The terms "including" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0054] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0055] See also Figure 1As shown, a redundant current detection system integrating a Hall sensor and a shunt is provided in one embodiment of the present application. The redundant current detection system integrating a Hall sensor and a shunt includes:

[0056] A first precision resistor 3, which is arranged in series on a loop formed by connecting the battery 1 and the load 2;

[0057] The second precision resistor 4 is connected in parallel with the first precision resistor 3, so that the first precision resistor 3 and the second precision resistor 4 together form a shunt, and the current in the loop formed by the connection between the battery and the load 2 will be shunted by the first precision resistor 3 and the second precision resistor 4 respectively, and because the resistance values ​​of the first precision resistor 3 and the second precision resistor 4 are respectively known, the resistance ratio of the first precision resistor 3 and the second precision resistor 4 is also known. According to Kirchhoff's law, the ratio between the first current and the second current obtained by shunting the first precision resistor 3 and the second precision resistor 4 is also known;

[0058] An analog front-end module 5, which is connected to the first precision resistor 3, and is used to measure the voltage drop across the first precision resistor 3; the analog front-end module 5 may be, but is not limited to, a voltage sensor, which can measure the voltage drop corresponding to the first precision resistor 3 across the two ends;

[0059] The analog front-end module 5 is also connected to the data processing unit 7 through the isolation communication module 6, so as to transmit the voltage drop to the data processing unit 7; the isolation communication module 6 has good isolation performance, and can isolate the communication between the analog front-end module 5 and the data processing unit 7 in a low-voltage area, thereby preventing the communication between the two from being broken down by high voltage, and improving the stability of the communication between the two;

[0060] The data processing unit 7 is used to calculate the first current on the first precision resistor 3 according to the voltage drop; when the data processing unit 7 receives the voltage drop, it can calculate the first current on the first precision resistor 3 according to the voltage drop and the resistance value of the first precision resistor 3;

[0061] A digital isolation Hall sensor 8 is connected in series with the second precision resistor 4 to measure the second current on the second precision resistor 4. The digital isolation Hall sensor 8 is small in size and has good stray magnetic field isolation and anti-interference performance. It is directly connected in series with the second precision resistor 4 and can directly measure the second current on the second precision resistor 4, so that heterogeneous current measurement of the second precision resistor 4 can be achieved.

[0062] The data processing unit 7 is also connected to the data isolation Hall sensor, which is used to measure the resistance values ​​of the first current, the second current, the first precision resistor 3 and the second precision resistor 4, determine the credibility of the current data, diagnose whether a hardware failure occurs in the redundant current detection system, and output the final measured current value. In this way, the measured first current and second current are expanded into three different current data: total current, Hall ratio total current and precision resistor total current, so as to improve the reliability of current detection and the accuracy of judging hardware equipment failures.

[0063] The beneficial effects of the above embodiments are as follows: the redundant current detection system integrating the Hall sensor and the shunt integrates the Hall sensor and the shunt to form a heterogeneous current measurement framework without increasing the volume of the current measurement device. Compared with the current measurement method formed by a single Hall sensor or a single shunt, it has higher security, and by using sensors and data transmission paths with different measurement principles, it effectively avoids the common cause failure problem of sensors with the same principle, so that the hardware has a higher detection and diagnosis coverage rate; in addition, CAN communication is used in signal interaction, and the low-voltage area is effectively isolated from the high-voltage area in hardware design, and the CAN communication is in the low-voltage area, so that the entire system has good insulation; and the Hall sensor is small in size, and its sensitivity to stray magnetic fields is low, and the problem of high processing difficulty is overcome, effectively reducing hardware costs and improving current detection accuracy.

[0064] In another embodiment, the digital isolation Hall sensor 8 and the isolation communication module 6 isolate the high voltage area and the low voltage area of ​​the redundant current detection system.

[0065] The beneficial effect of the above embodiment is that in actual operation, the digital isolation Hall sensor 8 and the isolation communication module 6 themselves have good isolation performance, which can isolate the high-voltage area and the low-voltage area of ​​the redundant current detection system, avoid the communication hardware of the redundant current detection system from being broken down by high voltage and unable to work normally, and improve the working stability of the redundant current detection system.

[0066] In another embodiment, the data processing unit 7 is connected to the digital isolation Hall sensor 8 via SPI and / or IIC, so as to obtain the second current measured by the digital isolation Hall sensor 8 .

[0067] The beneficial effect of the above embodiment is that the data processing unit 7 is connected to the digital isolation Hall sensor 8 via SPI and / or IIC, so that a stable and continuous communication connection can be achieved between the digital processing unit 7 and the digital isolation Hall sensor 8, avoiding the influence of high voltage from the battery 1.

[0068] In another embodiment, the data processing unit is connected to the digital isolation Hall sensor through SPI and IIC to obtain the second current measured by the digital isolation Hall sensor, including:

[0069] Step S1, the data processing unit simultaneously starts to obtain the second current measured by the digital isolation Hall sensor through SPI and IIC, and uses the following formula (1) to control the SPI and IIC of the data processing unit to be divided into a master-slave transmission scheme according to the change of the second current obtained multiple times,

[0070]

[0071] In the above formula (1), F represents the control value of the SPI and IIC of the data processing unit divided into the master-slave transmission scheme; I2(a+1) represents the second current value obtained for the a+1th time; I2(a) represents the second current value obtained for the ath time; I2(n) represents the second current value obtained for the nth time; I2(1) represents the second current value obtained for the 1st time; I0 represents the preset current threshold; n represents the total number of second currents obtained by a single transmission channel; It means that the maximum value of I2(a+1)-I2(a) is obtained under the condition of 1≤a≤n; && means AND operation. If both sides are true, the overall output value is 1, otherwise, the overall output value is 0;

[0072] If F=1, the transmission scheme of the data processing unit is SPI as the main transmission and IIC as the backup transmission;

[0073] If F=0, the transmission scheme of the data processing unit is that IIC is the main transmission and SPI is the backup transmission scheme;

[0074] Step S2, using the following formula (2), compare the data received under the primary and backup transmission schemes to control whether the backup transmission scheme is closed.

[0075]

[0076] In the above formula (2), B represents the control value of whether the backup transmission scheme is turned off; G_IIC 16 (k) indicates the kth data received under the IIC transmission channel; G_SPI 16 (k) represents the kth data received under the SPI transmission channel; m represents the total number of data obtained by a single transmission channel; F[], F{} both represent judgment functions. If the formula in the brackets is true, the function value of the judgment function is 1, otherwise, the function value of the judgment function is 0;

[0077] If B=1, the backup transmission scheme is controlled to be closed;

[0078] If B=0, the control standby transmission scheme is not closed;

[0079] Step S3: If the backup transmission scheme is not closed, the following formula (3) is used to control whether to merge the backup transmission scheme with the main transmission scheme to transmit data according to the amount of data received each time.

[0080]

[0081] In the above formula (3), H represents the control value of whether to merge and transmit data; S0 represents the preset data volume threshold; len[] represents the data volume of the data in the brackets;

[0082] If H=1, the backup transmission scheme is controlled and combined with the main transmission scheme to transmit data;

[0083] If H=0, the backup transmission scheme and the main transmission scheme are combined to transmit data without any control.

[0084] The beneficial effect of the above embodiment is that, by using the above formula (1), according to the change of the second current obtained multiple times, the SPI and IIC of the data processing unit are controlled to be divided into the main and standby transmission schemes, so that the appropriate transmission mode is selected according to the speed of change of the second current to ensure the reliability of data transmission; then by using the above formula (2), according to the data received under the main and standby transmission schemes, the comparison is performed to control whether the standby transmission scheme is closed, so that when the success rate of the main transmission is high, a separate transmission is performed to reduce system power consumption and control; then by using the above formula (3), according to the amount of data received each time, whether the backup transmission scheme is combined with the main transmission scheme to transmit data is controlled, and when the amount of data is large, the combined transmission is performed to improve the data transmission efficiency.

[0085] In another embodiment, the first precision resistor 3 , the second precision resistor 4 , the analog front-end module 5 , the isolated communication module 6 , the digital isolated Hall sensor 8 , and the data processing unit 7 are all arranged on the same PCB board.

[0086] The beneficial effects of the above embodiment are that the first precision resistor 3, the second precision resistor 4, the analog front-end module 5, the isolated communication module 6, the digital isolation Hall sensor 8, and the data processing unit 7 are all arranged on the same PCB board, which can not only improve the integration of the redundant current detection system, but also reduce the manufacturing cost of the redundant current detection system and ensure its manufacturing accuracy.

[0087] See also Figure 2 As shown, an embodiment of the present application provides a redundant current detection method for integrating a Hall sensor and a shunt. The redundant current detection method for integrating a Hall sensor and a shunt includes:

[0088] Step S1, measuring the voltage drop across the first precision resistor 3 through the analog front-end module 5; calculating the first current on the first precision resistor 3 according to the resistance value and the voltage drop of the first precision resistor 3 through the data processing unit 7; the analog front-end module 5 may be but is not limited to a voltage sensor, which can measure the voltage drop corresponding to the two ends of the first precision resistor 3, and transmit the measured voltage drop to the data processing unit 7, so that the data processing unit 7 divides the voltage drop by the resistance value of the first precision resistor 3, and can calculate the first current on the first precision resistor 3;

[0089] Step S2, measuring the second current on the second precision resistor 4 through the digital isolation Hall sensor 8, and obtaining the second current from the digital isolation Hall sensor 8 through the data processing unit 7; the digital isolation Hall sensor 8 is small in size and has good stray magnetic field isolation and anti-interference performance. It is directly connected in series with the second precision resistor 4 and can directly measure the second current on the second precision resistor 4, so that heterogeneous current measurement of the second precision resistor 4 can be achieved; it can be seen that the first current and the second current distribution are measured by sensors with different working principles, which can effectively avoid the occurrence of common cause failure;

[0090] Step S3, determining the corresponding total current according to the first current and the second current; determining the Hall ratio total current and the precision resistor total current according to the resistance values ​​of the first precision resistor 3 and the second precision resistor 4; thus expanding the measured first current and the second current into three different current data, namely, the total current, the Hall ratio total current and the precision resistor total current, to improve the reliability of current detection and the accuracy of judging hardware device failure;

[0091] Step S4, judging the credibility of the current data according to the total current, the Hall ratio total current and the precision resistor total current, diagnosing whether the redundant current detection system has a hardware failure, and outputting the final measured current value, by comparing and analyzing the total current, the Hall ratio total current and the precision resistor total current, determining the credibility of the three current data, and then diagnosing whether the redundant current detection system has a hardware failure, and outputting the final measured current value, thereby improving the accuracy of current detection.

[0092] The beneficial effects of the above embodiments are as follows: the redundant current detection method integrating the Hall sensor and the shunt integrates the Hall sensor and the shunt to form a heterogeneous current measurement framework without increasing the volume of the current measurement device. Compared with the current measurement method formed by a single Hall sensor or a single shunt, it has higher security, and by using sensors and data transmission paths with different measurement principles, it effectively avoids the common cause failure problem of sensors with the same principle, so that the hardware has a higher detection and diagnosis coverage rate; in addition, CAN communication is used in signal interaction, and the low-voltage area is effectively isolated from the high-voltage area in hardware design, and the CAN communication is in the low-voltage area, so that the entire system has good insulation; and the Hall sensor is small in size, and its sensitivity to stray magnetic fields is low, and the problem of high processing difficulty is overcome, effectively reducing hardware costs and improving current detection accuracy.

[0093] In another embodiment, before step S1, the method further includes:

[0094] According to the rated current information of the analog front-end module 5 and the digital isolation Hall sensor 8 , the resistance values ​​of the first precision resistor 3 and the second precision resistor 4 are adjusted.

[0095] The beneficial effect of the above embodiment is that the analog front-end module 5 and the digital isolated Hall sensor 8 each have a different rated current range. When the actual current of the analog front-end module 5 and the digital isolated Hall sensor 8 exceeds the upper limit of the corresponding rated current range, the analog front-end module 5 and the digital isolated Hall sensor 8 are easily damaged, thereby affecting the working reliability of the redundant current detection system; for this reason, according to the rated current information of the analog front-end module 5 and the digital isolated Hall sensor 8, the resistance values ​​of the first precision resistor 3 and the second precision resistor 4 are adjusted respectively, so that the actual current of the analog front-end module 5 and the digital isolated Hall sensor 8 can be maintained within the corresponding rated current range.

[0096] In another embodiment, in step S3, determining the corresponding total current according to the first current and the second current includes:

[0097] The first current and the second current are filtered by the data processing unit 7, and then the first current and the second current are added to obtain a total current;

[0098] or,

[0099] In step S3, according to the resistance values ​​of the first precision resistor 3 and the second precision resistor 4, the Hall proportional total current and the precision resistor total current are determined, including:

[0100] According to the resistance ratio between the first precision resistor 3 and the second precision resistor 4, the Hall proportional total current and the precision resistor total current are determined; wherein the Hall proportional total current refers to the total current value calculated based on the second current measured by the digital isolation Hogg sensor; the precision resistor total current refers to the total current value calculated based on the first current calculated by the data processing unit 7.

[0101] The beneficial effect of the above embodiment is that the first current and the second current are filtered by the data processing unit 7, and then the first current and the second current are added to obtain the total current, which can effectively reduce the interference noise inside the first current and the second current and improve the accuracy of the total current; wherein, the filtering of the first current and the second current can be but not limited to Kalman filtering. In addition, according to the resistance ratio between the first precision resistor 3 and the second precision resistor 4, the Hall ratio total current and the precision resistor total current are determined, so that the Hall ratio total current and the precision resistor total current can be calculated based on different measurement principles, thereby expanding the measured first current and second current into three different current data of total current, Hall ratio total current and precision resistor total current, in order to improve the reliability of current detection and the accuracy of judging hardware equipment failure.

[0102] In another embodiment, in step S4, the credibility of the current data is judged according to the total current, the Hall ratio total current and the precision resistor total current, and whether the redundant current detection system has a hardware failure is diagnosed, and the final measured current value is output, including:

[0103] According to the difference between any two of the total current, the Hall proportional total current and the precision resistor total current, the credibility of the current data is judged, the analog front-end module 5 and the digital isolation Hall sensor 8 are diagnosed whether there is a hardware failure, and the final measured current value is output.

[0104] The beneficial effect of the above embodiment is that in actual work, according to the difference between any two of the total current, the Hall ratio total current and the precision resistor total current, the credibility of the current data is judged, the analog front-end module 5 and the digital isolation Hall sensor 8 are diagnosed whether a hardware failure occurs, and the final measured current value is output. For example, the difference between any two of the total current, the Hall ratio total current and the precision resistor total current is subjected to threshold comparison and statistical analysis to obtain the credibility of each of the three current data, namely the total current, the Hall ratio total current and the precision resistor total current; when the credibility of a certain current data is less than the preset credibility threshold, it is determined that the measurement hardware corresponding to the current data (such as the analog front-end module or the digital isolation Hall sensor) is faulty, and the current data corresponding to the maximum credibility is output as the final measured current value.

[0105] In general, the redundant current detection system and method integrating the Hall sensor and the shunt integrate the Hall sensor and the shunt to form a heterogeneous current measurement framework without increasing the volume of the current measurement device. Compared with the current measurement method formed by a single Hall sensor or a single shunt, the redundant current detection system and method have higher security, and effectively avoid the common cause failure problem of sensors with the same principle by using sensors and data transmission paths with different measurement principles, so that the hardware has a higher detection and diagnosis coverage rate; in addition, CAN communication is used in signal interaction, and the low-voltage area is effectively isolated from the high-voltage area in hardware design, and the CAN communication is in the low-voltage area, so that the whole system has good insulation; and the Hall sensor is small in size, and its sensitivity to stray magnetic fields is low, and the problem of high processing difficulty is overcome, which effectively reduces the hardware cost and improves the accuracy of current detection.

[0106] The above is only a specific implementation of the present invention, and any other improvements made based on the concept of the present invention are considered to be within the protection scope of the present invention.

Claims

1. A redundant current detection system integrating a Hall sensor and a shunt, characterized in that: include: A first precision resistor is arranged in series on a loop formed by connecting the battery and the load; A second precision resistor, connected in parallel with the first precision resistor; an analog front-end module, connected to the first precision resistor, for measuring a voltage drop across the first precision resistor; The analog front-end module is also connected to the data processing unit via the isolation communication module, so as to transmit the voltage drop to the data processing unit; The data processing unit is used to calculate the first current on the first precision resistor according to the voltage drop; a digital isolation Hall sensor connected in series with the second precision resistor and used for measuring a second current on the second precision resistor; The data processing unit is also connected to the data isolation Hall sensor, and is used to measure the first current, the second current, the first precision resistor and the second precision resistor's respective resistance values, determine the credibility of the current data, diagnose whether the redundant current detection system has a hardware failure, and output the final measured current value.

2. The redundant current detection system integrating the Hall sensor and the shunt as claimed in claim 1, characterized in that: The digital isolation Hall sensor and the isolation communication module isolate the high voltage area and the low voltage area of ​​the redundant current detection system.

3. The redundant current detection system integrating the Hall sensor and the shunt as claimed in claim 1, characterized in that: The data processing unit is connected to the digital isolation Hall sensor via SPI and / or IIC, so as to obtain the second current measured by the digital isolation Hall sensor.

4. The redundant current detection system integrating the Hall sensor and the shunt as claimed in claim 3, characterized in that: The data processing unit is connected to the digital isolation Hall sensor through SPI and IIC to obtain the second current measured by the digital isolation Hall sensor, including: Step S1, the data processing unit simultaneously starts to obtain the second current measured by the digital isolation Hall sensor through SPI and IIC, and uses the following formula (1) to control the SPI and IIC of the data processing unit to be divided into a master-slave transmission scheme according to the change of the second current obtained multiple times, In the above formula (1), F represents the control value of the SPI and IIC of the data processing unit divided into the master-slave transmission scheme; I2(a+1) represents the second current value obtained for the a+1th time; I2(a) represents the second current value obtained for the ath time; I2(n) represents the second current value obtained for the nth time; I2(1) represents the second current value obtained for the first time; I0 represents the preset current threshold; n represents the total number of second currents obtained by a single transmission channel; Indicates that the maximum value of I2(a+1)-I2(a) is obtained under the condition of 1≤a≤n; && indicates an AND operation. If both sides are established, the overall output value is 1, otherwise, the overall output value is 0; if F=1, the transmission scheme of the data processing unit is SPI is the main transmission scheme, and IIC is the backup transmission scheme; If F=0, the transmission scheme of the data processing unit is that IIC is the main transmission and SPI is the backup transmission scheme; Step S2, using the following formula (2), compare the data received under the primary and backup transmission schemes to control whether the backup transmission scheme is closed. In the above formula (2), B represents the control value of whether the backup transmission scheme is shut down; G_IIC 16 (k) indicates the kth data received under the IIC transmission channel; G_SPI 16 (k) represents the kth data received under the SPI transmission channel; m represents the total number of data obtained by a single transmission channel; F[ ], F{} both represent judgment functions. If the equation in the brackets is true, the function value of the judgment function is 1, otherwise, the function value of the judgment function is 0; If B=1, the backup transmission scheme is controlled to be closed; If B=0, the control standby transmission scheme is not closed; Step S3: If the backup transmission scheme is not closed, the following formula (3) is used to control whether to merge the backup transmission scheme with the main transmission scheme to transmit data according to the amount of data received each time. In the above formula (3), H represents the control value of whether to merge and transmit data; S0 represents the preset data volume threshold; len[ ] represents the data volume of the data in the brackets; If H=1, the backup transmission scheme is controlled and combined with the main transmission scheme to transmit data; If H=0, the backup transmission scheme and the main transmission scheme are combined to transmit data without any control.

5. The redundant current detection system integrating the Hall sensor and the shunt as claimed in claim 1, characterized in that: The first precision resistor, the second precision resistor, the analog front-end module, the isolated communication module, the digital isolation Hall sensor, and the data processing unit are all arranged on the same PCB board.

6. A current detection method using a redundant current detection system in which a Hall sensor and a shunt are integrated as claimed in any one of claims 1 to 5, characterized in that: include: Step S1, measuring the voltage drop across the first precision resistor by the analog front-end module; Calculating, by the data processing unit, a first current on the first precision resistor according to the resistance value of the first precision resistor and the voltage drop; Step S2, measuring a second current on the second precision resistor by using the digital isolation Hall sensor, and acquiring the second current from the digital isolation Hall sensor by using the data processing unit; Step S3, determining a corresponding total current according to the first current and the second current; Determine the Hall proportional total current and the precision resistor total current according to the resistance values ​​of the first precision resistor and the second precision resistor; Step S4, judging the credibility of the current data according to the total current, the Hall proportional total current and the precision resistor total current, diagnosing whether the redundant current detection system has a hardware failure, and outputting the final measured current value.

7. The current detection method according to claim 6, characterized in that: Before step S1, the method further includes: According to the rated current information of the analog front-end module and the digital isolation Hall sensor, the resistance values ​​of the first precision resistor and the second precision resistor are adjusted.

8. The current detection method according to claim 6, characterized in that: In the step S3, determining the corresponding total current according to the first current and the second current includes: Performing filtering processing on the first current and the second current by the data processing unit, and then adding the first current and the second current to obtain the total current; or, In the step S3, determining the Hall proportional total current and the precision resistor total current according to the resistance values ​​of the first precision resistor and the second precision resistor respectively includes: According to the resistance ratio between the first precision resistor and the second precision resistor, the Hall proportional total current and the precision resistor total current are determined; wherein the Hall proportional total current refers to the total current value calculated based on the second current measured by the digital isolation Hogg sensor; the precision resistor total current refers to the total current value calculated based on the first current calculated by the data processing unit.

9. The current detection method according to claim 6, characterized in that: In the step S4, the credibility of the current data is judged according to the total current, the Hall ratio total current and the precision resistor total current, whether the redundant current detection system has a hardware failure is diagnosed, and the final measured current value is output, including: According to the difference between any two of the total current, the Hall proportional total current and the precision resistor total current, the credibility of the current data is judged, whether the analog front-end module and the digital isolation Hall sensor have hardware failures is diagnosed, and the final measured current value is output.

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