Detection circuit, battery system and vehicle

Abstract

The utility model discloses a detection circuit, a battery system and a vehicle, the detection circuit comprises a first voltage dividing branch circuit, a to-be-detected part and a second voltage dividing branch circuit, the detection circuit is configured to detect the to-be-detected part when the first voltage dividing branch circuit and the second voltage dividing branch circuit are in a conducting state, and the to-be-detected part is connected with the first voltage dividing branch circuit. A first sampling signal of the first end of the bridge wire resistor relative to the ground end and a second sampling signal of the second end of the bridge wire resistor relative to the ground end are obtained based on a first power supply, and the first sampling signal and the second sampling signal are output to a control branch; and the control branch determines the resistance value of the bridge wire resistor according to the first sampling signal and the second sampling signal. Therefore, not only can the measurement precision of the bridge wire resistance be improved, but also the circuit complexity and cost can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a detection circuit, a battery system and a vehicle. Background Art

[0002] In recent years, new energy vehicles have entered a stage of rapid development. New energy vehicles are generally equipped with high-voltage batteries. In the event of collision, short circuit, overcurrent and other emergencies, new energy vehicles can disconnect the power supply of the high-voltage battery in time by fusing the bridge wire resistor inside the Pyrofuse to avoid secondary disasters.

[0003] Currently, it is necessary to accurately measure the resistance value of the bridge wire resistor inside the Pyrofuse to avoid the need for power outage when an emergency occurs. However, in the related art, the solution for measuring the resistance value of the bridge wire resistor is not only complex in circuit design, but also has poor accuracy. Utility Model Content

[0004] The utility model mainly provides a detection circuit, a battery system and a vehicle, which can not only improve the measurement accuracy of the bridge wire resistance, but also reduce the circuit complexity and cost.

[0005] The technical solution of the utility model is achieved in this way:

[0006] In a first aspect, an embodiment of the utility model provides a detection circuit, the detection circuit comprising a first voltage division branch, a component to be tested, and a second voltage division branch, wherein:

[0007] One end of the first voltage-dividing branch is used to be connected to the first power supply, and the first voltage-dividing branch, the bridge wire resistor in the component to be tested, and the second voltage-dividing branch are connected in series, and the other end of the second voltage-dividing branch is used to be connected to the ground, and the first power supply, the first voltage-dividing branch, the component to be tested, the second voltage-dividing branch and the ground form a series loop, and the first voltage-dividing branch and the second voltage-dividing branch are used to connect the control branch;

[0008] The detection circuit is configured to obtain a first sampling signal of the first end of the bridge wire resistor relative to the ground and a second sampling signal of the second end of the bridge wire resistor relative to the ground based on the first power supply when both the first voltage-dividing branch and the second voltage-dividing branch are in the on state, and output the first sampling signal and the second sampling signal to the control branch, so that the control branch determines the resistance value of the bridge wire resistor according to the first sampling signal and the second sampling signal.

[0009] By means of the above technical means, when both the first voltage-dividing branch and the second voltage-dividing branch are in the on state, the first sampling signal and the second sampling signal are obtained, and the resistance value of the bridge wire resistor is further determined. In this way, not only the circuit is simplified, the circuit complexity and cost are reduced, but also the first sampling signal and the second sampling signal are collected at both ends of the bridge wire resistor, thereby improving the measurement accuracy of the bridge wire resistor.

[0010] In some embodiments, the first voltage dividing branch includes a first switching device and a first current limiting device, and the second voltage dividing branch includes a second switching device and a second current limiting device, wherein: one end of the first switching device is used to connect to the first power supply, and the first switching device, the first current limiting device, the bridge resistor, the second current limiting device and the second switching device are connected in series, and the other end of the second switching device is used to connect to the ground; the detection circuit is also configured to obtain the first sampling signal and the second sampling signal when the first switching device and the second switching device are both in the on state, and output the first sampling signal and the second sampling signal to the control branch.

[0011] By means of the above technical means, when both the first switch device and the second switch device are in the on state, the first sampling signal and the second sampling signal at both ends of the bridge wire resistor are obtained, so that the control branch can further determine the resistance value of the bridge wire resistor. In this way, the bridge wire resistor is measured based on a simple series circuit, which not only reduces the circuit complexity but also improves the measurement accuracy.

[0012] In some embodiments, the detection circuit also includes a driving branch, wherein: the input end of the driving branch is used to connect to the control branch, the output end of the driving branch is used to connect to the bridge wire resistor, the power supply end of the driving branch is used to connect to the second power supply, and the ground end of the driving branch is used to connect to the ground end; the driving branch is configured to obtain a control signal output by the control branch, and the control signal is used to control the conduction or shutdown of the driving branch; the detection circuit is also configured so that when the driving branch is in the on state, the driving circuit formed by the second power supply, the driving branch, the bridge wire resistor and the ground end is turned on to cause the bridge wire resistor to melt.

[0013] Through the above technical means, when the driving branch is in the on state, the circuit where the bridge wire resistor is located is turned on based on the current output by the second power supply, and the bridge wire resistor is fused. In this way, the bridge wire resistor can be fused in time when a vehicle fails, while ensuring that it can still work normally at other times, thereby improving the safety and reliability of the vehicle.

[0014] In some embodiments, the driving branch includes a high-side driving device and a low-side driving device, wherein: the input end of the high-side driving device is used to connect to the control branch, the output end of the high-side driving device is used to connect to the first end of the bridge wire resistor, and the power supply end of the high-side driving device is used to connect to the second power supply; the input end of the low-side driving device is used to connect to the control branch, the output end of the low-side driving device is used to connect to the second end of the bridge wire resistor, and the ground end of the low-side driving device is used to connect to the ground end; the detection circuit is also configured to turn on the driving loop formed by the second power supply, the high-side driving device, the bridge wire resistor, the low-side driving device and the ground end when both the high-side driving device and the low-side driving device are in the on state, so as to cause the bridge wire resistor to fuse.

[0015] By using the above technical means, the high-side driver and the low-side driver are connected to the bridge wire resistor, so that when a fault occurs, the high-side driver and the low-side driver are driven to conduct in time to form a loop, so that the second power supply outputs current to the bridge wire resistor through the conducted loop, so that the bridge wire resistor is melted. In this way, when a fault occurs, the bridge wire resistor can be melted in time, thereby improving the safety and reliability of the vehicle.

[0016] In some embodiments, the output end of the high-side driver device and the output end of the first current limiting device form a first wiring harness, and the first wiring harness is used to connect to the first end of the bridge resistor; the output end of the low-side driver device and the output end of the second current limiting device form a second wiring harness, and the second wiring harness is used to connect to the second end of the bridge resistor.

[0017] By using the above technical means, the high-side driver and the first current limiting device on the board are connected to the external bridge wire resistor through the first wiring harness, and the low-side driver and the second current limiting device are connected to the external bridge wire resistor through the second wiring harness. In this way, the reliability and maintainability of the circuit can be improved.

[0018] In some embodiments, the detection circuit is also configured to obtain a third sampling signal corresponding to the first end of the bridge wire resistor and a fourth sampling signal corresponding to the second end of the bridge wire resistor when both the first switching device and the second switching device are in the off state, and output the third sampling signal and the fourth sampling signal to the control branch, so that the control branch determines whether the first wiring harness and / or the second wiring harness is in a short power state based on the third sampling signal and the fourth sampling signal.

[0019] By means of the above technical means, when both the first switch device and the second switch device are in the off state, it is determined whether the first wiring harness and / or the second wiring harness is in the short power state according to the third sampling signal and the fourth sampling signal collected at both ends of the bridge wire resistor. In this way, errors due to circuit faults can be avoided in the subsequent measurement of the bridge wire resistor value, thereby improving the measurement accuracy.

[0020] In some embodiments, the detection circuit is also configured to obtain a fifth sampling signal corresponding to the first end of the bridge wire resistor and a sixth sampling signal corresponding to the second end of the bridge wire resistor when the first switching device is in an on state and the second switching device is in an off state, and output the fifth sampling signal and the sixth sampling signal to the control branch, so that the control branch determines whether the first wiring harness and / or the second wiring harness is in an open circuit state based on the fifth sampling signal and the sixth sampling signal.

[0021] By means of the above technical means, when the first switch device is in the on state and the second switch device is in the off state, it is determined whether the first wiring harness and / or the second wiring harness is in the open circuit state according to the fifth sampling signal and the sixth sampling signal collected at both ends of the bridge wire resistor. In this way, errors due to circuit faults can be avoided in the subsequent measurement of the bridge wire resistor, thereby improving the measurement accuracy.

[0022] In some embodiments, the detection circuit is also configured to obtain a seventh sampling signal corresponding to the first end of the bridge wire resistor and an eighth sampling signal corresponding to the second end of the bridge wire resistor when both the first switching device and the second switching device are in the on state, and output the seventh sampling signal and the eighth sampling signal to the control branch, so that the control branch determines whether the first wiring harness and / or the second wiring harness is in a short-to-ground state based on the seventh sampling signal and the eighth sampling signal.

[0023] By means of the above technical means, when both the first switch device and the second switch device are in the on state, it is determined whether the first wire harness and / or the second wire harness is in the short-to-ground state according to the seventh sampling signal and the eighth sampling signal collected at both ends of the bridge wire resistor. In this way, errors due to circuit faults can be avoided in subsequent measurements of the bridge wire resistor, thereby improving the measurement accuracy.

[0024] In some embodiments, the component to be tested includes a bridge wire resistor and a third switch device; wherein: the bridge wire resistor and the third switch device are connected in parallel, and the third switch device is connected in series in the high-voltage circuit.

[0025] By means of the above technical means, the bridge wire resistor is connected in parallel with the third switch device, and the third switch device is connected in series in the high-voltage circuit. In this way, when the bridge wire resistor is blown, the third switch device can be disconnected in time, thereby disconnecting the circuit of the high-voltage circuit, thereby improving the safety and reliability of the vehicle.

[0026] In a second aspect, an embodiment of the utility model provides a battery system, which includes a battery branch, a control branch and a detection circuit as described in any one of the first aspects; wherein: the control branch is used to connect to the detection circuit; the third switching device in the detection circuit is used to connect to the battery branch and form a high-voltage circuit.

[0027] In a third aspect, an embodiment of the utility model provides a vehicle, the vehicle comprising the battery system as described in the second aspect.

[0028] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and are not intended to limit the technical solutions of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 1 ;

[0030] Figure 2 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 2 ;

[0031] Figure 3 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 3 ;

[0032] Figure 4 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 4 ;

[0033] Figure 5 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 5 ;

[0034] Figure 6 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 6 ;

[0035] Figure 7 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 7 ;

[0036] Figure 8 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 8 ;

[0037] Fig. 9 A schematic diagram of the structure of a battery system provided by an embodiment of the utility model;

[0038] Fig.10 A schematic diagram of the structure of a vehicle provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0039] In order to more thoroughly understand the features and technical contents of the embodiments of the present invention, the implementation of the embodiments of the present invention is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not intended to limit the embodiments of the present invention.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the field of the present invention. The terms used herein are only for the purpose of describing the embodiments of the present invention and are not intended to limit the present invention.

[0041] In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0042] It should also be pointed out that the terms "first\second\third" involved in the embodiments of the present invention are only used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of the present invention described here can be implemented in an order other than that illustrated or described here.

[0043] In addition, the reference to "embodiment" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present invention. 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.

[0044] At present, new energy vehicles are developing rapidly, and the safety of high-voltage batteries in new energy vehicles and the protection of life and property of users are extremely important. When new energy vehicles have major accidents such as accidental collisions, fires, overcurrent, etc., in addition to traditional protection devices such as fuses and relays to quickly disconnect the power supply circuit of the high-voltage battery, active fuses Pyrofuse are also needed for rapid response protection.

[0045] Pyrofuse, also known as Pyroswitch, is called explosion fuse or high-temperature fuse, pyrotechnic control switch, instantaneous circuit breaker, etc. in Chinese. Pyrofuse technology is not new technology, but its use in battery systems is a new application. It comes from the detonation method of automobile airbags. When an external trigger signal is received, an explosion shock is generated by the explosion of gunpowder, which pushes the mechanical rod to move, disconnects the copper busbar connection, acts as a fuse or relay, and disconnects the high-voltage circuit. Pyrofuse detonation is detonated by an electrical signal to detonate the internal explosives. Specifically, Pyrofuse has a built-in bridge wire resistor, which is similar to a fuse. When a certain current passes through it, it will melt and cause an arc. The spark generated by the arc will ignite the explosive; the bridge wire resistor has a small resistance value, generally 1~3ohm when not detonated, and the resistance value is greater than 100ohm after detonation. The battery management system (BMS) can determine whether it has detonated by diagnosing the resistance value of the bridge wire resistor. At the same time, the diagnostic circuit will also determine whether its drive circuit has related faults.

[0046] When the Pyrofuse is not detonated, the resistance value of the bridge wire resistor inside it is generally small, and it is necessary to accurately detect its resistance value to determine whether the bridge wire resistance is normal, that is, to determine whether the resistance value of the bridge wire resistance is within the normal resistance value range when it is not detonated, so as to avoid the risk of failure to detonate. In the related art, by setting a constant current source and a signal amplification circuit outside the detection circuit, the voltage difference between the two ends of the bridge wire resistor is amplified and input through the differential amplifier in the signal amplification circuit, and the voltage difference signal is proportionally amplified by the signal amplifier and then output, and then according to the output voltage and current, the resistance value of the bridge wire resistor is calculated and determined based on Ohm's law. Although this scheme can realize the measurement of the resistance value of the bridge wire resistor in the Pyrofuse, it can only be realized based on the setting of a constant current source, a differential amplification circuit, etc., which not only has complex circuit design, high cost, poor chip replaceability, but also poor accuracy of the detected resistance value.

[0047] Based on this, the embodiment of the utility model provides a detection circuit, a battery system and a vehicle, which obtains a first sampling signal and a second sampling signal when the first voltage-dividing branch and the second voltage-dividing branch are both in a conducting state, and further determines the resistance value of the bridge wire resistor. In this way, not only the circuit is simplified, the circuit complexity and cost are reduced, but also the first sampling signal and the second sampling signal are collected at both ends of the bridge wire resistor, thereby improving the measurement accuracy of the bridge wire resistor.

[0048] The present invention is further described in detail below through the accompanying drawings and specific embodiments.

[0049] In one embodiment of the present invention, Figure 1A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 1 .like Figure 1 As shown, the detection circuit 10 includes a first voltage division branch 101, a component to be tested 102, and a second voltage division branch 103, wherein:

[0050] One end of the first voltage-dividing branch 101 is used to be connected to the first power supply 201, and the first voltage-dividing branch 101, the bridge wire resistor 1021 in the component to be tested 102 and the second voltage-dividing branch 103 are connected in series, and the other end of the second voltage-dividing branch 103 is used to be connected to the ground, and the first power supply 201, the first voltage-dividing branch 101, the component to be tested 102, the second voltage-dividing branch 103 and the ground form a series loop, and the first voltage-dividing branch 101 and the second voltage-dividing branch 103 are used to connect to the control branch 301;

[0051] The detection circuit 10 is configured to obtain a first sampling signal of the first end of the bridge resistor 1021 relative to the ground and a second sampling signal of the second end of the bridge resistor 1021 relative to the ground based on the first power supply 201 when both the first voltage-dividing branch 101 and the second voltage-dividing branch 103 are in the on state, and output the first sampling signal and the second sampling signal to the control branch 301, so that the control branch 301 determines the resistance value of the bridge resistor 1021 according to the first sampling signal and the second sampling signal.

[0052] In an embodiment of the utility model, the first voltage-dividing branch 101 and the second voltage-dividing branch 103 may include devices such as resistors and switches, which are used to provide voltage division for the bridge filament resistor 1021 to avoid circuit short circuit, and are also used to turn on or off based on the control signal sent by the control branch 301, thereby controlling the conduction or shutoff of the loop between the bridge filament resistor 1021 and the first power supply 201.

[0053] In the embodiment of the utility model, the first power supply 201 can be a constant voltage source, which is a power supply in the form of a system basis chip (System Basis Chip, SBC), a low dropout linear regulator (Low Dropout Regulator, LDO), a smart power module (Smart Power Module, SPM) from a power module in a BMS, and has a high precision characteristic. At the same time, the power network of the first power supply 201 has a common characteristic and can be used by any other functional module. When the load capacity meets the use conditions, no additional design is required, which can reduce costs.

[0054] In the embodiment of the utility model, the component to be tested 102, i.e., the Pyrofuse, can be provided with a bridge wire resistor 1021, which will be blown when a collision, short circuit, overcurrent or other safety fault occurs, so that the Pyrofuse can cut off the power supply in a very short time, thereby reducing the probability of danger. The overcurrent capacity of the Pyrofuse is relatively strong, and the software can make a real-time judgment according to the working conditions to determine whether to start the protection. Since the Pyrofuse is a protection device that is triggered by software and cuts off the circuit by blasting, it is necessary to accurately measure the resistance value of the bridge wire resistor 1021 in the Pyrofuse, and then determine the current, voltage and other parameters that can blow the bridge wire resistor 1021 to avoid the risk of failure to detonate.

[0055] It should be noted that, when the first voltage-dividing branch 101 and the second voltage-dividing branch 103 are both in the on state based on the control signal sent by the control branch 301, the series loop composed of the first power supply 201, the first voltage-dividing branch 101, the bridge wire resistor 1021, the second voltage-dividing branch 103 and the ground terminal is turned on, and the voltage value of the first end of the bridge wire resistor 1021 is collected as the first sampling signal, and the voltage value of the second end of the bridge wire resistor 1021 is collected as the second sampling signal, and sent to the control branch 301. The control branch 301 determines the voltage difference between the two ends of the bridge wire resistor 1021 according to the difference between the first sampling signal and the second sampling signal, and can also obtain the current value passing through the bridge wire resistor 1021 by collecting or based on the second sampling signal. Further, according to the voltage difference of the bridge wire resistor 1021 and the current value in the loop, the resistance value of the bridge wire resistor 1021 is determined based on Ohm's law.

[0056] It should also be noted that the control branch 301 can also detect whether there is a fault in the circuit by controlling the conduction or disconnection of the first voltage-dividing branch 101 and the second voltage-dividing branch 103. The specific scheme is described in detail in the following embodiments.

[0057] The embodiment of the utility model provides a detection circuit, which obtains a first sampling signal and a second sampling signal when both the first voltage-dividing branch and the second voltage-dividing branch are in a conducting state, and further determines the resistance value of the bridge wire resistor. In this way, not only the circuit is simplified, the circuit complexity and cost are reduced, but also the first sampling signal and the second sampling signal are collected at both ends of the bridge wire resistor, thereby improving the measurement accuracy of the bridge wire resistor.

[0058] In another embodiment of the present invention, Figure 2 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 2 .like Figure 2As shown, the first voltage dividing branch 101 includes a first switch device 1011 and a first current limiting device 1012, and the second voltage dividing branch 103 includes a second switch device 1032 and a second current limiting device 1031, wherein:

[0059] One end of the first switch device 1011 is used to connect to the first power supply 201, and the first switch device 1011, the first current limiting device 1012, the bridge resistor 1021, the second current limiting device 1031 and the second switch device 1032 are connected in series, and the other end of the second switch device 1032 is used to connect to the ground;

[0060] The detection circuit 10 is further configured to obtain a first sampling signal and a second sampling signal when both the first switch device 1011 and the second switch device 1032 are in an on state, and output the first sampling signal and the second sampling signal to the control branch 301 .

[0061] In the embodiment of the utility model, the first switch device 1011 can also be called a high-side switch, and the second switch device 1032 can also be called a low-side switch. The first switch device 1011 and the second switch device 1032 can be triodes, transistors, IGBTs, metal-oxide-semiconductor field-effect transistors (Metal-Oxide-Semiconductor Field-EffectTransistor, MOSFET), and can even be switching components, high-low-side chips, signal relays and other devices with switching functions. In addition, according to the channel type classification, at this time, the first switch tube Q1 can be an N-type switch tube, or it can also be a P-type switch tube; neither is specifically limited here. Among them, the first switch device 1011 can be turned on or off based on the first control signal sent by the control branch 301, and the second switch device 1032 can be turned on or off based on the second control signal sent by the control branch 301.

[0062] In the embodiment of the utility model, the first current limiting device 1012 and the second current limiting device 1031 may include a high-precision power resistor for setting the current size of the loop. It should be understood that when the first power supply 201 is a constant voltage source, the first power supply 201, the first switch device 1011, the first current limiting device 1012, the bridge wire resistor 1021, the second current limiting device 1031, the second switch device 1032, and the ground terminal, which can also be called the power ground terminal, are connected in series in sequence to form a series loop, and the loop current is determined by the first power resistor in the first current limiting device 1012 and the second power resistor in the second current limiting device 1031, and the resistance value of the bridge wire resistor 1021.

[0063] As mentioned above, since the resistance value of the bridge wire resistor 1021 is usually in the range of 1-3 ohms when not detonated, the resistance values ​​of the first power resistor in the first current limiting device 1012 and the second power resistor in the second current limiting device 1031 can be appropriately set to increase the loop current, thereby increasing the voltage drop across the bridge wire resistor 1021, and further improving the detection accuracy of the bridge wire resistor 1021. In other words, as long as the current is set within the tolerance range of the power resistor, the detection accuracy of the bridge wire resistor 1021 can be improved as much as possible while reducing the cost.

[0064] It should be noted that when the first switch device 1011 and the second switch device 1032 are both in the on state, the series circuit composed of the first power supply 201, the first switch device 1011, the first current limiting device 1012, the bridge resistor 1021, the second current limiting device 1031, the second switch device 1032, and the ground terminal connected in series in sequence is turned on, and the control branch 301 determines the voltage difference between the two ends of the bridge resistor 1021 according to the first sampling signal and the second sampling signal collected at the two ends of the bridge resistor 1021, and further according to the second sampling signal and the resistance value of the second current limiting device 1031, since the current in the series circuit is equal, it can be determined as the current value of the bridge resistor 1021. Finally, according to the voltage difference of the bridge resistor 1021 and the current value in the circuit, the resistance value of the bridge resistor 1021 is determined based on Ohm's law.

[0065] In addition, when the first switch device 1011 and the second switch device 1032 are both in the off state, or the first switch device 1011 is in the on state and the second switch device 1032 is in the off state, or the second switch device 1032 is in the on state and the first switch device 1011 is in the off state, the loop is disconnected and the resistance value of the bridge wire resistor 1021 cannot be measured.

[0066] Figure 3 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 3 .like Figure 3As shown, the first switch device is the first switch tube Q1, the second switch device is the second switch tube Q2, the first current limiting device is the first power resistor R1, and the second current limiting device is the second power resistor R2. The current value in the series circuit is determined by the first power resistor R1, the second power resistor R2 and the bridge wire resistor 1021. Therefore, after the control branch 301 controls the first switch tube Q1 and the second switch tube Q2 to be turned on, the voltage value at both ends of the bridge wire resistor 1021, that is, the voltage value at the first end of the bridge wire resistor 1021 can be collected as the first sampling signal, and the voltage value at the second end of the bridge wire resistor 1021 can be collected as the second sampling signal. Since the current in the series circuit is equal, the ratio of the voltage value in the second sampling signal to the resistance value of the second power resistor R2 can also be determined as the current value of the bridge wire resistor 1021. Further, the resistance value of the bridge wire resistor 1021 is determined according to the voltage difference of the bridge wire resistor 1021 and the current value passing through the bridge wire resistor 1021.

[0067] The embodiment of the utility model provides a detection circuit, which obtains the first sampling signal and the second sampling signal at both ends of the bridge wire resistor when the first switch device and the second switch device are both in the on state, so that the control branch can further determine the resistance value of the bridge wire resistor. In this way, the bridge wire resistor is measured based on a simple series circuit, which not only reduces the circuit complexity, but also improves the measurement accuracy.

[0068] In another embodiment of the present invention, Figure 4 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 4 .like Figure 4 As shown, the detection circuit 10 further includes a driving branch 104, wherein:

[0069] The input end of the driving branch 104 is used to connect to the control branch 301, the output end of the driving branch 104 is used to connect to the bridge wire resistor 1021, the power supply end of the driving branch 104 is used to connect to the second power supply 202, and the grounding end of the driving branch 104 is used to connect to the ground end;

[0070] The driving branch 104 is configured to obtain a control signal output by the control branch 301, and the control signal is used to control the on or off of the driving branch 104;

[0071] The detection circuit 10 is further configured such that when the driving branch 104 is in the on state, the driving loop formed by the second power supply 202, the driving branch 104, the bridge resistor 1021 and the ground terminal is turned on to fuse the bridge resistor 1021.

[0072] In an embodiment of the utility model, the driving branch 104 may include a driving chip, which is used to turn on or off based on the control signal output by the control branch 301, thereby controlling whether the second power supply 202 outputs current to the bridge wire resistor 1021, and further controlling whether the driving bridge wire resistor 1021 is blown.

[0073] It should be noted that the first switch device 1011 and the second switch device 1032 can be controlled by a control signal to enter a conducting state before the Pyrofuse starts working, and the resistance value of the bridge wire resistor 1021 in the Pyrofuse is detected. After determining that the resistance value of the bridge wire resistor 1021 is within a normal range, the Pyrofuse starts working. When a fault occurs, the first switch device 1011 and the second switch device 1032 are turned off, and the loop composed of the second power supply 202, the driving branch 104, and the bridge wire resistor 1021 is turned on, so that the bridge wire resistor 1021 is fused and the power supply is disconnected.

[0074] It should also be noted that, under normal working conditions, the drive circuit is not conducting, the bridge wire resistor 1021 is not blown, and the Pyrofuse works normally.

[0075] The embodiment of the utility model provides a detection circuit, when the driving branch is in the conducting state, based on the current output by the second power supply, the circuit where the bridge wire resistor is located is conducted, and the bridge wire resistor is fused. In this way, when a vehicle fails, the bridge wire resistor can be fused in time, while ensuring that it can still work normally at other times, thereby improving the safety and reliability of the vehicle.

[0076] In some embodiments, Figure 5 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 5 .like Figure 5 As shown, the driving branch includes a high-side driving device 1041 and a low-side driving device 1042, wherein:

[0077] The input end of the high-side driver 1041 is used to connect to the control branch 301, the output end of the high-side driver 1041 is used to connect to the first end of the bridge resistor 1021, and the power supply end of the high-side driver 1041 is used to connect to the second power supply 202;

[0078] The input end of the low-side driver 1042 is used to connect to the control branch 301, the output end of the low-side driver 1042 is used to connect to the second end of the bridge resistor 1021, and the ground end of the low-side driver 1042 is used to connect to the ground end;

[0079] The detection circuit 10 is also configured such that when both the high-side driver 1041 and the low-side driver 1042 are in the on state, the drive loop formed by the second power supply 202, the high-side driver 1041, the bridge resistor 1021, the low-side driver 1042 and the ground is turned on to melt the bridge resistor 1021.

[0080] In the embodiment of the present utility model, the high-side driver 1041 and the low-side driver 1042 may be devices such as MOS tubes and switch tubes, or may be switches with chips disposed inside.

[0081] In the embodiment of the present invention, the control branch 301 controls the on or off of the high-side driver 1041 through the third control signal, and controls the on or off of the low-side driver 1042 through the fourth control signal.

[0082] When a fault occurs, the control branch 301 controls the high-side driver 1041 and the low-side driver 1042 to be turned on, and the current output by the second power supply 202 flows through the bridge wire resistor 1021, causing the bridge wire resistor 1021 to fuse, the Pyrofuse to explode, and the circuit to be disconnected.

[0083] In normal working state, the control branch 301 controls the high-side driver 1041 and the low-side driver 1042 to be non-conductive, the bridge wire resistor 1021 does not melt, the Pyrofuse does not explode, and the circuit is powered normally.

[0084] In some embodiments, Figure 6 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 6 .like Figure 6 As shown, the driving branch may also include only the high-side driver device 1041, wherein: the input end of the high-side driver device 1041 is used to connect to the control branch 301, the output end of the high-side driver device 1041 is used to connect to the first end of the bridge wire resistor 1021, and the power supply end of the high-side driver device 1041 is used to connect to the second power supply 202.

[0085] The detection circuit 10 can also be configured such that when the high-side driver 1041 is in the on state, the drive loop formed by the second power supply 202, the high-side driver 1041, the bridge resistor 1021 and the ground is turned on to melt the bridge resistor 1021.

[0086] In some embodiments, Figure 7 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 7 .like Figure 7As shown, the driving branch may also include only the low-side driving device 1042, wherein: the input end of the low-side driving device 1042 is used to connect with the control branch 301, the output end of the low-side driving device 1042 is used to connect with the second end of the bridge wire resistor, and the ground end of the low-side driving device 1042 is used to connect with the ground end;

[0087] The detection circuit 10 can also be configured such that when the low-side driver 1042 is in the on state, the driving loop formed by the second power supply 202, the bridge resistor 1021, the low-side driver 1042 and the ground is turned on to melt the bridge resistor 1021.

[0088] The embodiment of the utility model provides a detection circuit, in which a high-side driver and a low-side driver are connected to a bridge wire resistor, so that when a fault occurs, the high-side driver and the low-side driver are promptly driven to conduct, forming a loop, so that the second power supply outputs current to the bridge wire resistor through the conducted loop, so that the bridge wire resistor is melted. In this way, when a fault occurs, the bridge wire resistor can be ensured to be melted in time, thereby improving the safety and reliability of the vehicle.

[0089] In some embodiments, see Figure 5 The output end of the high-side driver device 1041 and the output end of the first current limiting device 1012 form a first wiring harness 1051, and the first wiring harness 1051 is used to connect to the first end of the bridge wire resistor 1021; the output end of the low-side driver device 1042 and the output end of the second current limiting device 1031 form a second wiring harness 1052, and the second wiring harness 1052 is used to connect to the second end of the bridge wire resistor 1021.

[0090] In the embodiment of the utility model, the wires for outputting current or voltage from the high-side driver device 1041 and the wires between the first current limiting device 1012 and the bridge filament resistor 1021 are assembled into an arranged first wire harness 1051; the wires for inputting current or voltage from the low-side driver device 1042 and the wires between the second current limiting device 1031 and the bridge filament resistor 1021 are assembled into an arranged second wire harness 1052.

[0091] It should be noted that when the Pyrofuse does not require detonation, the BMS will perform open circuit, short circuit, and short power fault detection on the wiring harness of the Pyrofuse drive circuit, that is, the first wiring harness 1051 and the second wiring harness 1052, by controlling the conduction or disconnection of the first switch device 1011 and the second switch device 1032. It should be understood that when performing fault detection, the control branch can turn off the high-side driver device 1041 through the third control signal, and turn off the low-side driver device 1042 through the fourth control signal.

[0092] The embodiment of the utility model provides a detection circuit, which connects the high-side driver and the first current limiting device on the board to the external bridge wire resistor through the first wiring harness, and connects the low-side driver and the second current limiting device to the external bridge wire resistor through the second wiring harness. In this way, the reliability and maintainability of the circuit can be improved.

[0093] In another embodiment of the present invention, continue to refer to Figure 5 The detection circuit 10 is also configured to obtain a third sampling signal corresponding to the first end of the bridge wire resistor 1021 and a fourth sampling signal corresponding to the second end of the bridge wire resistor 1021 when both the first switch device 1011 and the second switch device 1032 are in the off state, and output the third sampling signal and the fourth sampling signal to the control branch 301, so that the control branch 301 determines whether the first wiring harness 1051 and / or the second wiring harness 1052 are in a short power state according to the third sampling signal and the fourth sampling signal.

[0094] In the embodiment of the utility model, the control branch 301 can turn off the first switch device 1011 based on the first control signal in the low level state, and turn off the second switch device 1032 based on the second control signal in the low level state. Further, the control branch 301 uses the voltage value of the first end of the bridge wire resistor 1021 as the first sampling signal, and uses the voltage value of the second end of the bridge wire resistor 1021 as the second sampling signal, and sends the first sampling signal and the second sampling signal to the control branch 301 through the wire. If the control branch 301 determines that the voltage value of the first sampling signal and the voltage value of the second sampling signal are consistent with the voltage value of the power supply in the BMS, the control branch 301 determines that the first wiring harness 1051 and / or the second wiring harness 1052 have a short power supply, that is, short-circuited to the power supply, that is, the first wiring harness 1051 and the second wiring harness 1052 are short-circuited to the second power supply 202. Otherwise, the first wiring harness 1051 and the second wiring harness 1052 are normal, and no fault is found.

[0095] It should be noted that the power supply in the BMS may be the aforementioned second power supply 202, or may be other lead-acid power supplies for powering the BMS.

[0096] The embodiment of the utility model provides a detection circuit, which determines whether the first wiring harness and / or the second wiring harness is in a short power state according to the third sampling signal and the fourth sampling signal collected at both ends of the bridge wire resistor when the first switch device and the second switch device are both in the off state. In this way, errors due to circuit failures can be avoided in subsequent measurements of the bridge wire resistor, thereby improving measurement accuracy.

[0097] In some embodiments, see Figure 5The detection circuit 10 is also configured to obtain a fifth sampling signal corresponding to the first end of the bridge wire resistor 1021 and a sixth sampling signal corresponding to the second end of the bridge wire resistor 1021 when the first switch device 1011 is in the on state and the second switch device 1032 is in the off state, and output the fifth sampling signal and the sixth sampling signal to the control branch 301, so that the control branch 301 determines whether the first wiring harness 1051 and / or the second wiring harness 1052 is in an open circuit state according to the fifth sampling signal and the sixth sampling signal.

[0098] In the embodiment of the utility model, the control branch 301 can also turn on the first switch device 1011 based on the first control signal in the high level state, and turn off the second switch device 1032 based on the second control signal in the low level state. In this case, if the voltage value of the first sampling signal collected by the first end of the bridge wire resistor 1021 is consistent with the voltage value of the first power supply, and the voltage value of the second sampling signal collected by the second end of the bridge wire resistor 1021 is 0V, it means that the first wiring harness 1051 and / or the second wiring harness 1052 has an open circuit. Alternatively, if the voltage value of the first sampling signal and the voltage value of the second sampling signal are consistent with the voltage value of the first power supply 201, it is determined that the first wiring harness 1051 and the second wiring harness 1052 are normal and no fault is found.

[0099] The embodiment of the utility model provides a detection circuit, which determines whether the first wiring harness and / or the second wiring harness is in an open circuit state according to the fifth sampling signal and the sixth sampling signal collected at both ends of the bridge wire resistor when the first switch device is in an on state and the second switch device is in an off state. In this way, errors due to circuit failures can be avoided in subsequent measurements of the bridge wire resistor, thereby improving measurement accuracy.

[0100] In some embodiments, see Figure 5 The detection circuit 10 is also configured to obtain a seventh sampling signal corresponding to the first end of the bridge wire resistor 1021 and an eighth sampling signal corresponding to the second end of the bridge wire resistor 1021 when both the first switch device 1011 and the second switch device 1032 are in the on state, and output the seventh sampling signal and the eighth sampling signal to the control branch 301, so that the control branch 301 determines whether the first wiring harness 1051 and / or the second wiring harness 1052 are in a short-to-ground state according to the seventh sampling signal and the eighth sampling signal.

[0101] In the embodiment of the utility model, the control branch 301 can also turn on the first switch device 1011 based on the first control signal in the high level state, and turn on the second switch device 1032 based on the second control signal in the high level state. In this case, if the voltage value of the first sampling signal collected at the first end of the bridge wire resistor 1021 and the voltage value of the second sampling signal collected at the second end of the bridge wire resistor 1021 are both small and close to 0V, the control branch 301 determines that the first wiring harness 1051 and / or the second wiring harness 1052 are short-circuited to the ground terminal connected to the second switch device 1032. Alternatively, if the first sampling signal and the second sampling signal are not close to 0V, it is determined that the first wiring harness 1051 and the second wiring harness 1052 are both normal and no fault is found.

[0102] It should also be noted that after completing the above fault detection and determining that there is no abnormality in the first wiring harness 1051 and the second wiring harness 1052, the resistance value of the bridge wire resistor 1021 can be determined based on the scheme of measuring the resistance value of the bridge wire resistor 1021 in the above embodiment. If any item in the above fault detection process fails, an alarm can be issued, and the fault detection is performed again after the fault is eliminated until the fault detection passes.

[0103] The embodiment of the utility model provides a detection circuit, which determines whether the first wire harness and / or the second wire harness is in a short-to-ground state according to the seventh sampling signal and the eighth sampling signal collected at both ends of the bridge wire resistor when the first switch device and the second switch device are both in the on state. In this way, errors due to circuit failures can be avoided in subsequent measurements of the bridge wire resistor, thereby improving measurement accuracy.

[0104] In some embodiments, Figure 8 A schematic diagram of the structure of a detection circuit provided in an embodiment of the utility model Figure 8 .like Figure 8 As shown, the component to be tested includes a bridge resistor 1021 and a third switch device 1022; wherein: the bridge resistor 1021 and the third switch device 1022 are connected in parallel, and the third switch device 1022 is connected in series in the high-voltage circuit. Specifically, one end of the third switch device 1022 is connected to the positive terminal (+) in the high-voltage circuit, and the other end of the third switch device 1022 is connected to the negative terminal (-) in the high-voltage circuit.

[0105] In the embodiment of the utility model, the bridge wire resistor 1021 and the third switch device 1022 can be set in the component to be tested, which can also be called Pyrofuse. Among them, the bridge wire resistor 1021 is a resistor with a relatively small resistance value, and the third switch device 1022 can be a switch component, or MOS, etc.

[0106] It should be noted that the detection circuit performs open circuit, short circuit, short power supply and other fault detection on the first wire harness 1051 and the second wire harness 1052 connected to the bridge wire resistor 1021. After confirming that there is no fault, the resistance value of the bridge wire resistor 1021 can be detected to determine the resistance value of the bridge wire resistor 1021.

[0107] Furthermore, based on the resistance value of the bridge wire resistor 1021, in the event of a vehicle failure, the control branch causes the high-side driver 1041 and the low-side driver 1042 to be turned on based on the output control signal, and causes the bridge wire resistor 1021 to fuse based on the current output by the second power supply 202, thereby detonating the internal explosion fuel between the bridge wire resistor 1021 and the third switch device 1022, driving the piston device between the bridge wire resistor 1021 and the third switch device 1022 to move quickly, cutting off the copper bar in the third switch device 1022, that is, turning off the third switch device 1022, thereby cutting off the high-voltage circuit where the third switch device 1022 is located, thereby achieving power outage.

[0108] In other cases, the high-side driver 1041 and the low-side driver 1042 are not turned on, the bridge resistor 1021 is normal, the third switch device 1022 is in the on state, the BMS works normally, and the high-voltage circuit is powered normally.

[0109] The embodiment of the utility model provides a detection circuit, which connects the bridge wire resistor in parallel with the third switch device, and the third switch device is connected in series in the high-voltage circuit. In this way, when the bridge wire resistor is blown, the third switch device can be disconnected in time, thereby disconnecting the circuit of the high-voltage circuit, thereby improving the safety and reliability of the vehicle.

[0110] In another embodiment of the present invention, Fig. 9 The following is a schematic diagram of the structure of a battery system provided by an embodiment of the utility model. Fig. 9 As shown, the battery system 30 includes a battery branch 302, a control branch 301 and the detection circuit 10 in the above-mentioned embodiment; wherein:

[0111] The control branch 301 is used to connect with the detection circuit 10;

[0112] The third switch device 1022 in the detection circuit 10 is used to connect with the battery branch 302 and form a high-voltage loop.

[0113] In the embodiment of the present invention, one end of the third switch device 1022 is connected to the positive terminal (+) of the battery branch 302, and the other end of the third switch device 1022 is connected to the negative terminal (-) of the battery branch 302 to form a high voltage loop.

[0114] In the embodiment of the utility model, the control branch 301 may be a microcontroller unit (MCU), which is used to send a first control signal to the first switch device 1011 in the detection circuit 10, and send a second control signal to the second switch device 1032 in the detection circuit 10, so as to control the on and off of the first switch device 1011 and the second switch device 1032. The control branch 301 may also send a third control signal to the high-side driver device 1041 in the detection circuit 10 to control the on or off of the high-side driver device 1041, or send a fourth control signal to the low-side driver device 1042 in the detection circuit 10 to control the on or off of the low-side driver device 1042. In the aforementioned embodiment, the control branch 301 may also determine the resistance value of the bridge wire resistor 1021 based on the first sampling signal, the second sampling signal, and the resistance value of the second current limiting device 1031.

[0115] In the embodiment of the utility model, when the Pyrofuse is not required to be detonated, the BMS will detect the open circuit, short circuit and short power fault of the first wire harness 1051 and the second wire harness 1052 in the Pyrofuse driving circuit including the high-side driver device 1041, the bridge wire resistor 1021 and the low-side driver device 1042, and will further detect the resistance value of the bridge wire resistor of the Pyrofuse.

[0116] First, the Pyrofuse drive circuit can be tested for open circuit, short circuit, and short power faults in the wiring harness.

[0117] Before the resistance value of the bridge wire resistor 1021 is detected, the pyrofuse drive harness can be diagnosed for a fault. The third control signal and the fourth control signal of the control branch 301 are in a low level state, so that the high-side driver 1041 and the low-side driver 1042 are not closed, and the following fault diagnosis can be performed:

[0118] In the first case, the first control signal and the second control signal do not close the first switch device 1011 and the second switch device 1012. If the first sampling signal and the second sampling signal collect a voltage value consistent with the voltage value of the power supply of the BMS, it means that the first wiring harness 1051 and / or the second wiring harness 1052 is short-circuited, otherwise the wiring harness is normal.

[0119] In the second case, the first control signal causes the first switch device 1011, that is, the high-side switch to close, and the second control signal causes the second switch device 1032, that is, the low-side switch to not close. If the first sampling signal collects a voltage value consistent with the voltage of the first power supply 201, and the second sampling signal collects 0V, it means that the wiring harness is open. If the first sampling signal and the second sampling signal collect voltage values ​​consistent with the voltage of the first power supply 201, it means that the wiring harness is normal.

[0120] In the third case, the first control signal closes the first switch device 1011, and the second control signal closes the second switch device 1032. If the first sampling signal and the second sampling signal collect less than or close to 0V, it indicates that the wiring harness is short-grounded. If the first sampling signal and the second sampling signal collect not close to 0V, the resistance value detection of the bridge wire resistor 1021 can be continued.

[0121] Furthermore, the resistance value of the bridge wire resistor 1021 may be detected.

[0122] During resistance detection, the third control signal and the fourth control signal of the control branch 301 are in a low level state, so that the high-side driver 1041 and the low-side driver 1042 are not closed. The first control signal and the second control signal close the first switch device 1011 and the second switch device 1032, and a series loop consisting of "first power supply 201-first switch device 1011-first current limiting device 1012-first wiring harness 1051-bridge wire resistor 1021 in pyrofuse-second current limiting device 1031-second switch device 1032-power ground" is formed, and the loop current is determined by the voltage of the first power supply 201, the bridge wire resistor 1021, the first current limiting device 1012 and the second current limiting device 1031.

[0123] The first power supply 201 is a power supply in the form of SBC, LDO, SPM, etc. from the BMS power module, which has high precision. At the same time, the power supply network has a shared characteristic and can be used by any other functional module. If the load capacity meets the use conditions, no additional design is required, and the cost can be reduced.

[0124] The first current limiting device 1012 and the second current limiting device 1031 are mainly composed of high-precision power resistors, which are used to set the current size of the loop. When the voltage of the first power supply 201 is known, the current of the loop is determined by the power resistor and the bridge wire resistor 1021. Because the resistance of the bridge wire resistor 1021 in the pyrofuse is usually in the range of 1~3ohm when it is not detonated, the appropriate setting of the power resistor resistance can increase the loop current, thereby increasing the voltage drop across the bridge wire resistor 1021 and improving the resistance detection accuracy of the bridge wire resistor 1021. As long as the current is set within the tolerance range of the power resistor, it has the characteristics of high precision and low cost.

[0125] The first switch device 1011 is a switch device connected to the positive terminal of the first power supply 201, and the second switch device 1032 is a switch device connected to the negative terminal of the power supply. The on and off of the control loop is controlled. The first switch device 1011 and the second switch device 1032 are closed simultaneously only when the pyrofuse resistance value needs to be detected. The switch device can be a device with a switch function such as a MOS, a triode, a high-side or low-side chip, a signal relay, etc.

[0126] After determining the resistance value of the bridge wire resistor 1021, when the Pyrofuse driver requires detonation, the high-side driver 1041 and the low-side driver 1042 are respectively turned on by the high-level third control signal and the fourth control signal of the control branch 301, so that the Pyrofuse drive circuit is turned on and detonated, and the high-voltage circuit where the third switch device is located is further turned off, and the battery branch 302 stops supplying power. Alternatively, when the pyrofuse does not require detonation, the third control signal and the fourth control signal of the control branch 301 are in a low-level state, the high-side driver 1041 and the low-side driver 1042 are turned off, the Pyrofuse drive circuit is not turned on, the high-voltage circuit where the third switch device 1022 is located is turned on, and the battery branch 302 is powered normally.

[0127] In the embodiment of the utility model, as shown in Table 1, taking the second power supply 202 as KL30, the first power supply 201 as VCC, and the first power resistor R1 and the second power resistor R2 as 25Ω as an example, when the voltage value of VCC is 5V, and the voltage value of KL30 is 8V, 12V or 16V respectively, when it is determined that the Pyrofuse is not detonated, the resistance value of the bridge wire resistor 1021 is 1.7Ω, 2Ω or 2.3Ω respectively; after the Pyrofuse is detonated, the resistance value of the bridge wire resistor 1021 is 100Ω. That is to say, when the output voltage of the second power supply 202 changes, based on the detection circuit 10 in the embodiment of the utility model, it is still possible to accurately detect whether the resistance value of the bridge wire resistor 1021 is within the normal range.

[0128] Table 1

[0129]

[0130] In the embodiment of the utility model, as shown in Table 2, it shows that the voltage value of the first sampling signal, the voltage value of the second sampling signal and the resistance value of the bridge wire resistor 1021 are collected when the first switch device 1011 and the second switch device 1032 are both closed, and under the conditions of detonation or non-detonation. According to Table 2, it can be seen that even if there is an error in the circuit, it is possible to accurately detect whether the resistance value of the bridge wire resistor 1021 when it is not detonated is within the normal range, and measure the resistance value of the bridge wire resistor 1021 when it is not detonated. In addition, Table 2 also shows the voltage values ​​of the first sampling signal and the second sampling signal when the first switch device 1011 and the second switch device 1032 are both turned off and under the short circuit condition. It can be seen that when the output voltage of the power supply of the BMS is 12V, if the first wiring harness 1051 and / or the second wiring harness 1052 has a short power supply failure, the voltage value of the first sampling signal and the voltage value of the second sampling signal are both 12V. Table 2 also shows the voltage value of the first sampling signal and the voltage value of the second sampling signal when the first switch device 1011 is closed, the second switch device 1032 is turned off, and the circuit is open. It can be seen that when the output voltage of the first power supply 201 is 5V, if the first wiring harness 1051 and / or the second wiring harness 1052 has an open circuit fault, the voltage value of the first sampling signal is equal to the output voltage of the first power supply, both of which are 5V, and the voltage value of the second sampling signal is 0.

[0131] Table 2

[0132]

[0133] Table 2 also shows the voltage value of the first sampling signal and the voltage value of the second sampling signal when the first switch device 1011 and the second switch device 1032 are both closed and the first sampling signal is shorted to ground or the second sampling signal is shorted to ground. It can be seen that if the first wiring harness 1051 and / or the second wiring harness 1052 is shorted to ground, the voltage value of the first sampling signal and the voltage value of the second sampling signal are both 0V or close to 0V.

[0134] The embodiment of the utility model provides a battery system, which can not only realize the small resistance detection of the bridge wire resistor in the Pyrofuse, but also has a simple circuit design, low cost and high resistance detection accuracy. In addition, it can also realize the diagnosis of open circuit, short power supply, short ground and other faults of the wiring harness connected to the Pyrofuse without the need for additional configuration devices.

[0135] In another embodiment of the present invention, Fig.10 The following is a schematic diagram of the structure of a vehicle provided by an embodiment of the utility model. Fig.10 As shown, a vehicle 40 includes the battery system 30 of the aforementioned embodiment.

[0136] In the embodiment of the present utility model, the vehicle 40 may be a new energy vehicle, for example, the vehicle 40 may be an electric vehicle, a hybrid vehicle, an electric motorcycle or other device having a battery system.

[0137] It should be understood that those skilled in the art should understand that the present invention can be implemented in the form of hardware embodiments, software embodiments, or embodiments combining software and hardware. Moreover, the present invention can be implemented in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program codes.

[0138] It should also be understood that "one embodiment" or "an embodiment" mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the utility model. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in various embodiments of the utility model, the size of the serial numbers of the above-mentioned steps / processes does not mean the order of execution. The execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the utility model. The serial numbers of the above-mentioned embodiments of the utility model are only for description and do not represent the advantages and disadvantages of the embodiments.

[0139] It should be noted that, in the present utility model, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0140] In the several embodiments provided by the present utility model, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0141] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in each embodiment of the utility model, each functional unit may be fully integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0142] The above description is only a preferred embodiment of the present utility model and is not intended to limit the protection scope of the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included in the protection scope of the present utility model.

Claims

1. A detection circuit, characterized in that: The detection circuit comprises a first voltage-dividing branch, a component to be tested and a second voltage-dividing branch, wherein: One end of the first voltage-dividing branch is used to be connected to a first power supply, and the first voltage-dividing branch, the bridge wire resistor in the component to be tested and the second voltage-dividing branch are connected in series, the other end of the second voltage-dividing branch is used to be connected to a ground terminal, the first power supply, the first voltage-dividing branch, the component to be tested, the second voltage-dividing branch and the ground terminal form a series loop, and the first voltage-dividing branch and the second voltage-dividing branch are used to connect a control branch; The detection circuit is configured to obtain a first sampling signal of the first end of the bridge wire resistor relative to the ground end and a second sampling signal of the second end of the bridge wire resistor relative to the ground end based on the first power supply when both the first voltage-dividing branch and the second voltage-dividing branch are in an on state, and output the first sampling signal and the second sampling signal to the control branch, so that the control branch determines the resistance value of the bridge wire resistor according to the first sampling signal and the second sampling signal.

2. The detection circuit according to claim 1, characterized in that: The first voltage dividing branch includes a first switch device and a first current limiting device, and the second voltage dividing branch includes a second switch device and a second current limiting device, wherein: One end of the first switch device is used to be connected to the first power supply, and the first switch device, the first current limiting device, the bridge resistor, the second current limiting device and the second switch device are connected in series, and the other end of the second switch device is used to be connected to the ground terminal; The detection circuit is further configured to obtain the first sampling signal and the second sampling signal when the first switching device and the second switching device are both in an on state, and output the first sampling signal and the second sampling signal to the control branch.

3. The detection circuit according to claim 2, characterized in that: The detection circuit also includes a driving branch, wherein: The input end of the driving branch is used to be connected to the control branch, the output end of the driving branch is used to be connected to the bridge wire resistor, the power supply end of the driving branch is used to be connected to the second power supply, and the grounding end of the driving branch is used to be connected to the ground; The driving branch is configured to obtain a control signal output by the control branch, wherein the control signal is used to control the on or off of the driving branch; The detection circuit is further configured such that when the driving branch is in a conducting state, a driving loop formed by the second power supply, the driving branch, the bridge wire resistor and the ground terminal is turned on to cause the bridge wire resistor to fuse.

4. The detection circuit according to claim 3, characterized in that: The driving branch includes a high-side driving device and a low-side driving device, wherein: The input end of the high-side driver device is used to be connected to the control branch, the output end of the high-side driver device is used to be connected to the first end of the bridge wire resistor, and the power supply end of the high-side driver device is used to be connected to the second power supply; The input end of the low-side driver device is used to be connected to the control branch, the output end of the low-side driver device is used to be connected to the second end of the bridge wire resistor, and the ground end of the low-side driver device is used to be connected to the ground end; The detection circuit is also configured to, when both the high-side driver and the low-side driver are in an on state, turn on the drive loop formed by the second power supply, the high-side driver, the bridge wire resistor, the low-side driver and the ground terminal to melt the bridge wire resistor.

5. The detection circuit according to claim 4, characterized in that: The output end of the high-side driver and the output end of the first current limiting device form a first wiring harness, and the first wiring harness is used to connect to the first end of the bridge wire resistor; The output end of the low-side driver device and the output end of the second current limiting device form a second wiring harness, and the second wiring harness is used to be connected to the second end of the bridge wire resistor.

6. The detection circuit according to claim 5, characterized in that: The detection circuit is also configured to obtain a third sampling signal corresponding to the first end of the bridge wire resistor and a fourth sampling signal corresponding to the second end of the bridge wire resistor when both the first switching device and the second switching device are in the off state, and output the third sampling signal and the fourth sampling signal to the control branch, so that the control branch determines whether the first wiring harness and / or the second wiring harness is in a short power state according to the third sampling signal and the fourth sampling signal.

7. The detection circuit according to claim 5, characterized in that: The detection circuit is also configured to obtain a fifth sampling signal corresponding to the first end of the bridge wire resistor and a sixth sampling signal corresponding to the second end of the bridge wire resistor when the first switching device is in an on state and the second switching device is in an off state, and output the fifth sampling signal and the sixth sampling signal to the control branch, so that the control branch determines whether the first wiring harness and / or the second wiring harness is in an open circuit state according to the fifth sampling signal and the sixth sampling signal.

8. The detection circuit according to claim 7, characterized in that: The detection circuit is also configured to obtain a seventh sampling signal corresponding to the first end of the bridge wire resistor and an eighth sampling signal corresponding to the second end of the bridge wire resistor when both the first switching device and the second switching device are in the on state, and output the seventh sampling signal and the eighth sampling signal to the control branch, so that the control branch determines whether the first wiring harness and / or the second wiring harness is in a short-to-ground state based on the seventh sampling signal and the eighth sampling signal.

9. The detection circuit according to any one of claims 1 to 8, characterized in that: The component to be tested includes the bridge wire resistor and a third switch device; wherein: The bridge wire resistor and the third switch device are connected in parallel, and the third switch device is connected in series in the high-voltage loop.

10. A battery system, characterized in that: The battery system comprises a battery branch, a control branch and a detection circuit as claimed in any one of claims 1 to 9; wherein: The control branch is used to connect with the detection circuit; The third switch device in the detection circuit is used to connect with the battery branch to form a high-voltage loop.

11. A vehicle, characterized in that: The vehicle includes the battery system as claimed in claim 10.

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