Protection device, battery management system, battery equipment and vehicle

Abstract

The utility model relates to a protection device, a battery management system, battery equipment and a vehicle, a forward surge signal and a reverse surge signal of a charging loop can be acquired in real time through an acquisition circuit, and both the forward surge signal and the reverse surge signal can be converted into a forward electric signal suitable for comparison through a signal processing circuit, so that the positive electric signal and the reverse electric signal can be compared. And the voltage is output to the trigger comparison circuit to be compared with the voltage of the reference voltage source. If the voltage of the forward electric signal is larger than the voltage of the reference voltage source, it is determined that overcurrent protection is triggered. At the moment, under the action of an output signal of the trigger comparison circuit, the first switch circuit triggers the action, the charging loop is cut off, and the charging operation is interrupted. According to the scheme, no matter whether a forward surge signal or a reverse surge signal occurs in the charging loop, overcurrent protection can be triggered, the triggering frequency of the protection device is improved, and high operation reliability is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of current detection, in particular to a protection device, a battery management system, a battery equipment and a vehicle. BACKGROUND

[0002] With the development of science and technology, electric vehicles such as electric motorcycles and electric cars powered by batteries are used more and more widely in daily life, bringing great traffic convenience to people. In order to meet the endurance requirements, the batteries of electric vehicles are often charged through charging piles. If the charging current is too large, the battery is easy to be damaged, so it is particularly important to protect the battery from overcurrent.

[0003] However, in the related art, when a surge occurs in the charging circuit, the protection device often does not perform a protection action, and the operation reliability of the protection device is poor. UTILITY MODEL CONTENT

[0004] Therefore, a protection device, a battery management system, a battery equipment and a vehicle are provided to improve the operation reliability of the protection device.

[0005] The present application provides a protection device, comprising a collection circuit, a signal processing circuit, a trigger comparison circuit and a first switch circuit, the collection circuit is arranged in a charging circuit, and the collection circuit is used to capture a forward surge signal and a reverse surge signal of the charging circuit; the signal processing circuit is connected to the collection circuit, and the signal processing circuit is used to convert the forward surge signal or the reverse surge signal into a forward electric signal and output; a first input end of the trigger comparison circuit is connected to the signal processing circuit, and a second input end of the trigger comparison circuit is used to connect a reference voltage source; the trigger comparison circuit is used to trigger overcurrent protection when the voltage of the forward electric signal is greater than the voltage of the reference voltage source; the first switch circuit is arranged in the charging circuit and connected to an output end of the trigger comparison circuit; and the first switch circuit is used to cut off the charging circuit when the trigger comparison circuit triggers overcurrent protection.

[0006] The protection device can collect the forward surge signal and the reverse surge signal of the charging circuit in real time through the acquisition circuit, and can convert the forward surge signal and the reverse surge signal into a forward electric signal suitable for comparison through the signal processing circuit, and output the forward electric signal to the trigger comparison circuit for comparison with the voltage of the reference voltage source. If the voltage of the forward electric signal is greater than the voltage of the reference voltage source, the overcurrent protection is triggered. At this time, under the action of the output signal of the trigger comparison circuit, the first switch circuit is triggered to act, and the charging circuit is cut off to interrupt the charging operation. Through the scheme, the overcurrent protection can be triggered whether the forward surge signal or the reverse surge signal of the charging circuit appears, the triggering frequency of the protection device is improved, and the operation reliability is high.

[0007] In some embodiments, the protection device further comprises a delay comparison circuit, an output end of the trigger comparison circuit is connected to the first switch circuit through the delay comparison circuit; the delay comparison circuit is used for starting a delay function when the trigger comparison circuit triggers the overcurrent protection, and outputting an off signal to the first switch circuit when the trigger comparison circuit maintains triggering the overcurrent protection within a preset delay time length; and the first switch circuit is used for cutting off the charging circuit when receiving the off signal.

[0008] The scheme further provides the delay comparison circuit between the trigger comparison circuit and the first switch circuit, and the overcurrent protection needs to be triggered for a time length reaching the preset delay time length when the trigger comparison circuit triggers the overcurrent protection, and then the power supply of the charging circuit is controlled to be cut off, so that the possibility of false triggering of the overcurrent protection is reduced.

[0009] In some embodiments, the delay comparison circuit comprises a second switch circuit, a charging circuit and a comparison circuit, a control end of the second switch circuit is connected to an output end of the trigger comparison circuit, an input end of the second switch circuit is connected to a power supply end of the comparison circuit, the power supply end of the comparison circuit is used for connecting a first power supply, an output end of the second switch circuit is connected to the charging circuit, the charging circuit is connected to a first input end of the comparison circuit, a second input end of the comparison circuit is used for connecting a second power supply, and an output end of the comparison circuit is connected to the first switch circuit.

[0010] The scheme realizes the delay triggering of the overcurrent protection through the charging of the charging circuit to a certain voltage value, and has simple circuit structure and implementation manner, and effectively saves the circuit cost.

[0011] In some embodiments, the delay comparison circuit further comprises an adjustable voltage dividing circuit, and a second input end of the comparison circuit is connected to the second power supply through the adjustable voltage dividing circuit.

[0012] The second input end of the comparison circuit is connected with the second power supply through the adjustable voltage dividing circuit, so that the reference voltage of the input comparison circuit is adjusted, and the preset delay time of the delay comparison circuit is changed, and the application range of the protection device is widened.

[0013] In some embodiments, the charging circuit includes a first capacitor, a first end of the first capacitor is connected with the output end of the second switch circuit, and a second end of the first capacitor is connected with the first input end of the comparison circuit.

[0014] The above scheme uses the first capacitor as the charging circuit, has a simple implementation manner, and can effectively save the circuit volume and circuit cost.

[0015] In some embodiments, the charging circuit includes a second capacitor, a third capacitor and a diode, a first end of the second capacitor and an anode of the diode are connected with the output end of the second switch circuit, a cathode of the diode is connected with a first end of the third capacitor and the first input end of the comparison circuit, and a second end of the second capacitor and a second end of the third capacitor are grounded.

[0016] The above scheme uses the second capacitor, the third capacitor and the diode to form the charging circuit, and the diode can realize the anti-reverse protection and the freewheeling function while realizing the delay function, so that the voltage of the charging circuit is stabilized, and the operation reliability of the charging circuit is improved.

[0017] In some embodiments, the second capacitor includes an adjustable capacitor, and / or the third capacitor includes an adjustable capacitor.

[0018] The above scheme configures the second capacitor and / or the third capacitor as an adjustable capacitor, so that the charging time of the charging circuit is adjusted, and the application range of the protection device is widened.

[0019] In some embodiments, the comparison circuit includes a first comparator and a first current limiting resistor, a power supply end of the first comparator is connected with the first power supply and the input end of the second switch circuit, a first input end of the first comparator is connected with the charging circuit, a second input end of the first comparator is used for connecting the second power supply, a ground end of the first comparator is grounded, and an output end of the first comparator is connected with the first switch circuit through the first current limiting resistor.

[0020] The above scheme uses the first comparator and the first current limiting resistor to form the comparison circuit, which can not only realize the comparison function, but also limit the current flowing into the first switch circuit, so that the operation safety of the protection device is improved.

[0021] In some embodiments, the trigger comparison circuit comprises a second comparator and a second current-limiting resistor, a first input end of the second comparator is connected to the signal processing circuit, a second input end of the second comparator is used for connecting the reference voltage source, and an output end of the second comparator is connected to the first switch circuit through the second current-limiting resistor.

[0022] The above scheme forms the trigger comparison circuit through the second comparator and the second current-limiting resistor, realizes the comparison function, limits the current flowing into the subsequent circuit, and further improves the operation safety of the protection device.

[0023] In some embodiments, the first switch circuit comprises a first switch device and a relay, a control end of the first switch device is connected to the output end of the trigger comparison circuit, an input end of the first switch device is connected to a first end of a coil of the relay, a second end of the coil of the relay is used for connecting a third power supply, an output end of the first switch device is grounded, and the switch of the relay is connected in series to the charging circuit.

[0024] The above scheme, the first switch circuit comprises a first switch device and a relay, and the relay is used to realize the on-off control of the charging circuit, so that the on-off control reliability of the charging circuit is high.

[0025] In some embodiments, the signal processing circuit comprises a rectifier circuit, and the acquisition circuit is connected to the first input end of the trigger comparison circuit through the rectifier circuit.

[0026] The above scheme uses the rectifier circuit to realize the processing of the forward surge signal and the reverse surge signal, so that a forward electric signal capable of reasonably representing the size of the surge signal is obtained, and the trigger accuracy of the overcurrent comparison circuit is improved.

[0027] The application provides a battery management system comprising a charging circuit and the above protection device.

[0028] The application provides a battery equipment comprising a battery and the above battery management system.

[0029] The application provides a vehicle comprising a driving assembly and the above battery equipment. BRIEF DESCRIPTION OF DRAWINGS

[0030] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments, and are not intended to limit the scope of the application. Moreover, the same reference numerals in all the drawings represent the same or similar elements. In the drawings:

[0031] Figure 1 It is a schematic diagram of the protection device in some embodiments of the application.

[0032] Figure 2 Structure diagram of protection device in some other embodiments of the present application;

[0033] Figure 3 Structure diagram of protection device in some other embodiments of the present application;

[0034] Figure 4 Structure diagram of protection device in some other embodiments of the present application;

[0035] Figure 5 Structure diagram of protection device in some other embodiments of the present application;

[0036] Figure 6 Structure diagram of protection device in some other embodiments of the present application;

[0037] Figure 7 Structure diagram of protection device in some other embodiments of the present application;

[0038] Figure 8 Structure diagram of protection device in some other embodiments of the present application;

[0039] Figure 9 Structure diagram of protection device in some other embodiments of the present application.

[0040] Explanation of reference signs:

[0041] 10 - acquisition circuit, 20 - signal processing circuit, 30 - trigger comparison circuit, 40 - first switch circuit, 50 - delay comparison circuit; 51 - second switch circuit, 52 - charging circuit, 53 - comparison circuit; 54 - adjustable voltage dividing circuit; C1 - first capacitor, Ra - first resistor, Rb - second resistor; C2 - second capacitor, C3 - third capacitor, D - diode, Q1 - first comparator, R1 - first current limiting resistor, Q2 - second comparator, R2 - second current limiting resistor, K1 - first switching device, J0 - relay, 21 - rectifier circuit; Vr - reference voltage source, V1 - first power supply, V2 - second power supply, V3 - third power supply. DETAILED DESCRIPTION

[0042] The embodiments of the technical scheme of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical scheme of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application; the use of the terms "including," "comprising," or "having" and variations thereof herein is intended to be broad and encompass the terms "consisting of" and "consisting essentially of" and variations thereof. Unless otherwise required by context, singular terms shall include pluralities and vice versa. Unless otherwise required by context, the use herein of the singular is also to be construed as a use of the plural and vice versa.

[0044] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly and specifically limited.

[0045] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification is not necessarily all referring to the same embodiment, or to an independent or alternative embodiment, in isolation from other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0046] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0047] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0048] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanical connection, or it can be electrical connection; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0049] At present, from the development of market situation, the application of battery is more and more extensive. Not only be applied to the energy storage system of hydropower, thermal power, wind power and solar power station, but also be widely used in electric vehicles such as electric bicycles, electric motorcycles, electric vehicles, and many other fields such as military equipment and aerospace. With the continuous expansion of the application field of battery, the demand of its market is also increasing.

[0050] During the use of the battery, it needs to be charged to supplement the electric energy. If the current of the charging circuit is too large, the battery is easy to be damaged. Therefore, a protection device is generally configured. When the surge occurs in the charging circuit, the protection device cuts off the charging circuit, thereby protecting the safety of the battery.

[0051] However, although the protection device is configured, the phenomenon of battery damage due to overcurrent during charging still occurs. Through in-depth research, it is found that the phenomenon of battery damage due to overcharging at the present stage usually occurs in the case of negative surge in the charging circuit. Since the negative surge cannot be identified by the protection device, the overcurrent protection cannot be triggered.

[0052] In order to alleviate the above phenomenon, a protection device capable of identifying both positive surge signal and negative surge signal can be considered, so that overcurrent protection can be triggered whether positive surge or negative surge occurs in the charging circuit.

[0053] Based on the above consideration, the protection device provided in the present application can collect the positive surge signal and the negative surge signal of the charging circuit in real time through the acquisition circuit, and whether the positive surge signal or the negative surge signal can be converted into a positive electric signal suitable for comparison by the signal processing circuit, and output to the trigger comparison circuit for comparison with the voltage of the reference voltage source. If the voltage of the positive electric signal is greater than the voltage of the reference voltage source, it is determined that the overcurrent protection is triggered. At this time, under the action of the output signal of the trigger comparison circuit, the first switch circuit will trigger the action to cut off the charging circuit and interrupt the charging operation.

[0054] Through the above scheme, whether the positive surge signal or the negative surge signal occurs in the charging circuit, the overcurrent protection can be triggered, the trigger frequency of the protection device is improved, and the operation reliability is high.

[0055] The protection device provided in the present application is applied in the charging circuit of the battery to perform overcurrent protection on the charging circuit. The charging circuit can be configured separately, for example, configured in the controller or processor of the electric device; or integrated in the battery management system of the battery, which is not limited.

[0056] Among them, the battery can be a power battery used in electric vehicles such as electric vehicles, or a battery used to provide electric energy in other types of electric devices, which is also not limited.

[0057] Referring to Figure 1 The application provides a protection device, which comprises a collection circuit 10, a signal processing circuit 20, a trigger comparison circuit 30 and a first switch circuit 40. The collection circuit 10 is arranged in a charging circuit (not shown in the figure), and is used for capturing a forward surge signal and a reverse surge signal of the charging circuit. The signal processing circuit 20 is connected to the collection circuit 10, and is used for converting the forward surge signal or the reverse surge signal into a forward electric signal and outputting. The first input end of the trigger comparison circuit 30 is connected to the signal processing circuit 20, and the second input end of the trigger comparison circuit 30 is used for connecting a reference voltage source (Vr shown in the figure). The trigger comparison circuit 30 is used for triggering overcurrent protection when the voltage of the forward electric signal is greater than the voltage of the reference voltage source. The first switch circuit 40 is arranged in the charging circuit and is connected to the output end of the trigger comparison circuit 30. The first switch circuit 40 is used for cutting off the charging circuit when the trigger comparison circuit 30 triggers overcurrent protection.

[0058] Specifically, the collection circuit 10 is a circuit capable of collecting current signals flowing through the charging circuit in real time. The forward surge signal refers to an electric signal flowing through the charging circuit when the current rapidly increases and exceeds the normal working range, which can be expressed by a current signal or a voltage signal. The reverse surge refers to an electric signal flowing through the charging circuit when the inductive element of the circuit releases electric energy and flows back to the charging circuit in the form of reverse current in an abnormal state, which can also be expressed by a current signal or a voltage signal. The signal processing circuit 20 refers to a circuit capable of performing maintaining processing on the input forward surge signal and reverse processing on the input reverse surge signal. The trigger comparison circuit 30 is a circuit for comparing the output of the signal processing circuit 20 with a reference voltage signal, so as to determine whether overcurrent protection needs to be triggered according to the comparison result. The first switch circuit 40 is a circuit capable of maintaining the closure of the charging circuit through switching action or cutting off the charging circuit according to the comparison result of the trigger comparison circuit 30.

[0059] The collection circuit 10 is arranged in the charging circuit, and can monitor the surge of the circuit during the charging of the battery by the charging circuit. The collection circuit 10 can collect the electric signals of the charging circuit in real time and send them to the processor. Correspondingly, when the surge phenomenon occurs, the surge signals can also be collected and sent to the processor in time, that is, the capture of the surge signals (including the forward surge signal and the reverse surge signal) is realized.

[0060] The signal processing circuit 20 can convert and process the real-time collected electric signal of the collecting circuit 10, obtain a forward electric signal and transmit it to the trigger comparison circuit 30 for comparison with the voltage signal of the reference voltage source input to the trigger comparison circuit 30. In a normal state, the voltage of the electric signal output by the signal processing circuit 20 should be less than the voltage of the reference voltage source, at which time the trigger comparison circuit 30 outputs a first level signal (which can be a high level or a low level according to actual requirements). In the case of a surge phenomenon, the electric signal output by the collecting circuit 10 is a forward surge signal or a reverse surge signal, and the voltage of the forward electric signal output by the signal processing circuit 20 will be greater than the voltage of the reference voltage source, so that the trigger comparison circuit 30 outputs a second level signal (opposite to the first level signal). The output of the second level signal by the trigger comparison circuit 30 represents triggering of the overcurrent protection, and the first switching circuit 40 will be triggered off under the action of the second level signal, thereby cutting off the charging circuit and interrupting the charging to complete the overcurrent protection.

[0061] It should be pointed out that the specific type of the collecting circuit 10 is not unique, and any circuit that can withstand surge impact and real-time feedback of the collection result to the signal processing circuit 20 can be used. For example, in an embodiment, the collecting circuit 10 can include a current transformer (CT). In another embodiment, the capture of the forward surge signal and the reverse surge signal can also be realized by a resistance shunt circuit, a Hall current sensor circuit, etc., and the specific implementation is not limited.

[0062] The above protection device can real-time collect the forward surge signal and the reverse surge signal of the charging circuit through the collecting circuit 10, and whether it is a forward surge signal or a reverse surge signal, it can be converted into a suitable forward electric signal by the signal processing circuit 20 and output to the trigger comparison circuit 30 for comparison with the voltage of the reference voltage source. If the voltage of the forward electric signal is greater than the voltage of the reference voltage source, it is determined to trigger the overcurrent protection. At this time, under the action of the output signal of the trigger comparison circuit 30, the first switching circuit 40 will trigger and act, cutting off the charging circuit and interrupting the charging operation. Through this scheme, whether it is a forward surge signal or a reverse surge signal of the charging circuit, the overcurrent protection can be triggered, the triggering frequency of the protection device is improved, and the operation reliability is high.

[0063] Please refer to Figure 2In some embodiments, the protection device further comprises a delay comparison circuit 50, the output end of the trigger comparison circuit 30 is connected to the first switch circuit 40 through the delay comparison circuit 50; the delay comparison circuit 50 is configured to start a delay function when the trigger comparison circuit 30 triggers the overcurrent protection, and output a shutdown signal to the first switch circuit 40 when the trigger comparison circuit 30 maintains triggering the overcurrent protection within a preset delay time; and the first switch circuit 40 is configured to cut off the charging circuit when receiving the shutdown signal.

[0064] Specifically, the delay comparison circuit 50 detects the triggering duration of the overcurrent protection when triggering the overcurrent protection, and controls the first switch circuit 40 to act when the triggering duration reaches the preset delay time, so as to execute the overcurrent protection function circuit. In actual scenarios, in order to reduce the possibility of mistaking the peak current as a surge signal and improve the overcurrent protection reliability of the protection device, the delay comparison circuit 50 needs to be arranged between the trigger comparison circuit 30 and the first switch circuit 40.

[0065] In this way, when triggering the overcurrent protection through the trigger detection circuit, the delay comparison circuit 50 starts the delay function, and the charging circuit will not be cut off within the preset delay time. If the overcurrent protection is triggered continuously within the preset delay time, so that the delay comparison circuit 50 meets certain conditions, a shutdown signal is output to control the first switch circuit 40 to cut off the charging circuit. If the overcurrent protection is not triggered continuously within the preset delay time, the delay comparison circuit 50 will not meet the above conditions, and no shutdown signal is output, so the first switch circuit 40 will not act, and the charging circuit will maintain conduction.

[0066] The above scheme further arranges the delay comparison circuit 50 between the trigger comparison circuit 30 and the first switch circuit 40, and needs to trigger the overcurrent protection continuously for a preset delay time when the trigger comparison circuit 30 triggers the overcurrent protection, and then controls the charging circuit to be powered off, which can reduce the possibility of false triggering of the overcurrent protection.

[0067] Please refer to Figure 2 In some embodiments, the delay comparison circuit 50 comprises a second switch circuit 51, a charging circuit 52 and a comparison circuit 53, the control end of the second switch circuit 51 is connected to the output end of the trigger comparison circuit 30, the input end of the second switch circuit 51 is connected to the power supply end of the comparison circuit 53, the power supply end of the comparison circuit 53 is configured to be connected to a first power supply (V1 shown in the figure), the output end of the second switch circuit 51 is connected to the charging circuit 52, the charging circuit 52 is connected to the first input end of the comparison circuit 53, the second input end of the comparison circuit 53 is configured to be connected to a second power supply (V2 shown in the figure), and the output end of the comparison circuit 53 is connected to the first switch circuit 40.

[0068] Specifically, the second switch circuit 51 is turned on or turned off by the level signal output by the trigger comparison circuit 30, so that the charging circuit 52 charges or stops charging. The charging circuit 52 is a circuit that can increase the voltage by charging when the first power supply is connected. The comparison circuit 53 is a circuit that compares the voltage of the charging circuit 52 and the voltage of the second power supply, and changes the output level signal when the voltage of the charging circuit 52 is greater than the voltage of the second power supply.

[0069] When the trigger comparison circuit 30 does not trigger the overcurrent protection, the first level signal is input to the control end of the second switch circuit 51, and the second switch circuit 51 is turned off under the action of the first level signal. At this time, since the charging circuit 52 does not store electric energy, the voltage of the first input end of the comparison circuit 53 is 0, and the voltage value of the second input end is greater than that of the first input end. The comparison circuit 53 outputs the first level signal (which can also be a high level signal or a low level signal, which is different according to the polarity of the two input ends), and the first switch circuit 40 maintains the on state, so that the charging loop continues to operate in a closed state.

[0070] When the trigger comparison circuit 30 triggers the overcurrent protection, the second level signal is input to the control end of the second switch circuit 51, and the second switch circuit 51 is turned on under the action of the second level signal. The charging circuit 52 is connected with the first power supply, and the charging circuit 52 is charged by the first power supply. With the increase of charging time, the voltage of the charging circuit 52 will eventually be greater than the voltage of the first power supply (at this time, it is indicated that the delay time reaches the preset delay time, and the trigger comparison circuit 30 continues to trigger the overcurrent protection), and the comparison circuit 53 will switch to output the second level signal, that is, the off signal. Under the action of the second level signal, the first switch circuit 40 is switched to the off state, so as to cut off the charging loop. If the trigger comparison circuit 30 does not trigger the overcurrent protection when the voltage of the charging circuit 52 is not greater than the voltage of the first power supply, the charging circuit 52 will interrupt the charging, and at this time the voltage of the charging circuit 52 will not continue to increase, and the comparison circuit 53 will not act.

[0071] It should be pointed out that the above-mentioned first power supply and second power supply can be the same power supply or different power supplies, and the specific limitation is not made.

[0072] The above-mentioned scheme realizes the delay trigger of the overcurrent protection by the charging of the charging circuit 52 to a certain voltage value, and the circuit structure and implementation mode are simple, which effectively saves the circuit cost.

[0073] It can be understood that the structure of the second switch circuit 51 is not unique, and in an embodiment, the second switch circuit 51 can include a switching device, which can be a field effect tube, a crystal triode, or an insulated gate bipolar transistor, and the like, and the specific limitation is not made. In another embodiment, the second switch circuit 51 can include a switching device and a current limiting resistor, and the input end of the switching device is connected to the power supply end of the comparison circuit 53 through the current limiting resistor, so that the operation safety of the switching device can be improved.

[0074] Please refer to Figure 3 In some embodiments, the delay comparison circuit 50 further includes an adjustable voltage dividing circuit 54, and the second input end of the comparison circuit 53 is connected to the second power supply through the adjustable voltage dividing circuit 54.

[0075] Specifically, the adjustable voltage dividing circuit 54 is a voltage dividing circuit whose voltage dividing value can be adjusted. Please refer to Figure 4 The voltage dividing circuit includes a first resistor Ra and a second resistor Rb connected in series, one end of the first resistor Ra away from the second resistor Rb is connected to the second power supply, one end of the second resistor Rb away from the first resistor Ra is grounded, and the common end of the two resistors is connected to the second input end of the comparison circuit 53. Among them, the first resistor Ra and / or the second resistor Rb can be configured as an adjustable resistor, and by adjusting the resistance value of the voltage dividing resistor, the voltage value input to the second input end of the comparison circuit 53 can be changed.

[0076] Correspondingly, if the voltage value input to the second input end is reduced, the charging circuit 52 only needs to reach a lower voltage to change the output state of the comparison circuit 53, and at this time, the preset delay time length will also be reduced. If the voltage value input to the second input end is increased, the charging circuit 52 needs to reach a higher voltage to change the output state of the comparison circuit 53, and at this time, the preset delay time length will also be increased.

[0077] The above scheme, the second input end of the comparison circuit 53 is connected to the second power supply through the adjustable voltage dividing circuit 54, so that the reference voltage input to the comparison circuit 53 is adjusted, and the preset delay time length of the delay comparison circuit 50 is changed, and the application range of the protection device is widened.

[0078] Please refer to Figure 4 In some embodiments, the charging circuit 52 includes a first capacitor C1, the output end of the second switch circuit 51 is connected to the first end of the first capacitor C1, and the second end of the first capacitor C1 is connected to the first input end of the comparison circuit 53.

[0079] Specifically, the type of the charging circuit 52 is not unique, and a first capacitor C1 can be used as the charging circuit 52. When the first capacitor C1 is charged to a certain extent, for example, full, the voltage value at the first input end of the comparison circuit 53 can be greater than the voltage value at the second input end, so as to realize the delay triggering of the overcurrent protection.

[0080] It should be noted that, in an embodiment, the first capacitor C1 is an adjustable capacitor. Thus, when the voltage value at the second input end of the comparison circuit 53 changes, the charging time and the voltage value of the first capacitor C1 can be changed by adjusting the capacitance value of the first capacitor C1, so as to expand the application range of the protection device.

[0081] The above scheme uses the first capacitor C1 as the charging circuit 52, and the implementation is simple, which can effectively save the circuit size and the circuit cost.

[0082] Please refer to Figure 5 In some embodiments, the charging circuit 52 includes a second capacitor C2, a third capacitor C3, and a diode D. The output end of the second switch circuit 51 is connected to the first end of the second capacitor C2 and the anode of the diode D. The cathode of the diode D is connected to the first end of the third capacitor C3 and the first input end of the comparison circuit 53. The second end of the second capacitor C2 and the second end of the third capacitor C3 are grounded.

[0083] Specifically, the scheme of the embodiment includes two capacitors and a diode D. When the overcurrent protection is triggered, the second switch circuit 51 is turned on to charge the second capacitor C2 and the third capacitor C3, so as to realize the delay triggering function. When the surge disappears, the charging circuit 52 can not only quickly realize the energy discharge, but also can reduce the possibility of energy backflow to the second switch circuit 51 to a certain extent.

[0084] The above scheme uses the second capacitor C2, the third capacitor C3, and the diode D to form the charging circuit 52. The delay function can be realized, and the anti-reverse protection and the freewheeling function can be realized through the diode D, so as to stabilize the voltage of the charging circuit 52 and improve the operation reliability of the charging circuit 52.

[0085] In some embodiments, the second capacitor C2 includes an adjustable capacitor, and / or the third capacitor C3 includes an adjustable capacitor.

[0086] Specifically, the second capacitor C2 and the third capacitor C3 can be capacitors with fixed capacitance values. Alternatively, the second capacitor C2 can be configured as an adjustable capacitor, and / or the third capacitor C3 can be configured as an adjustable capacitor. In actual scenarios, the capacitance values of the second capacitor C2 and / or the third capacitor C3 can be adjusted according to different delay triggering requirements, so as to change the voltage value and the charging time of the charging circuit 52.

[0087] For example, when the voltage value of the second input end of the comparison circuit 53 changes, the capacitance value of the second capacitor C2 and / or the third capacitor C3 can be changed accordingly to match the voltage value of the second input end, so that the voltage value of the charging circuit 52 and the charging time are more matched with the voltage value of the second input end.

[0088] The above scheme configures the second capacitor C2 and / or the third capacitor C3 as an adjustable capacitor, so that the charging time of the charging circuit 52 is adjusted, and the application range of the protection device is widened.

[0089] The structure of the comparison circuit 53 is not unique. In an embodiment, the comparison circuit 53 includes a comparator, and the power supply end, the first input end and the second input end of the comparator are respectively the power supply end, the first input end and the second input end of the comparison circuit 53.

[0090] In another embodiment, referring to Figure 5 , the comparison circuit 53 includes a first comparator Q1 and a first current limiting resistor R1. The power supply end of the first comparator Q1 is connected to the first power supply and the input end of the second switch circuit 51. The first input end of the first comparator Q1 is connected to the charging circuit 52. The second input end of the first comparator Q1 is connected to the second power supply. The ground end of the first comparator Q1 is grounded. The output end of the first comparator Q1 is connected to the first switch circuit 40 through the first current limiting resistor R1.

[0091] Specifically, the voltage of the charging circuit 52 and the voltage of the second power supply are input to the first comparator Q1 to realize the comparison function. Further, the first current limiting resistor R1 is arranged between the output of the first comparator Q1 and the first switch circuit 40 to limit the current of the electric signal flowing into the first switch circuit 40, thereby reducing the possibility of damage of the first switch circuit 40 due to overcurrent.

[0092] The above scheme builds the comparison circuit 53 by the first comparator Q1 and the first current limiting resistor R1, which realizes the comparison function and limits the current flowing into the first switch circuit 40, thereby improving the operation safety of the protection device.

[0093] Similarly, the structure of the trigger comparison circuit 30 is not unique. In an embodiment, the trigger comparison circuit 30 includes a comparator, and the power supply end, the first input end and the second input end of the comparator are respectively the power supply end, the first input end and the second input end of the trigger comparison circuit 30.

[0094] In another embodiment, referring to Figure 6The trigger comparison circuit 30 comprises a second comparator Q2 and a second current limiting resistor R2, the first input end of the second comparator Q2 is connected to the signal processing circuit 20, the second input end of the second comparator Q2 is connected to a reference voltage source, and the output end of the second comparator Q2 is connected to the first switch circuit 40 through the second current limiting resistor R2.

[0095] Specifically, the voltage of the forward electric signal and the voltage of the reference voltage source are input to the second comparator Q2, so as to realize the trigger comparison function. Further, the first current limiting resistor R1 is arranged between the output of the second comparator Q2 and the subsequent circuit (for example, the delay comparison circuit 50), so as to limit the current size of the electric signal flowing into the subsequent circuit, and reduce the possibility of damage of the subsequent circuit due to overcurrent.

[0096] The above scheme forms the trigger comparison circuit 30 through the second comparator Q2 and the second current limiting resistor R2, realizes the comparison function, limits the current flowing into the subsequent circuit, and further improves the operation safety of the protection device.

[0097] Please refer to Figure 7 In some embodiments, the first switch circuit 40 comprises a first switching device K1 and a relay J0, the control end of the first switching device K1 is connected to the output end of the trigger comparison circuit 30, the input end of the first switching device K1 is connected to the first end of the coil of the relay J0, the second end of the coil of the relay J0 is connected to a third power supply (V3 shown in the figure), the output end of the first switching device K1 is grounded, and the switch of the relay J0 is connected in series in the charging circuit.

[0098] Specifically, in the case of triggering overcurrent protection or triggering overcurrent protection for a preset delay duration, the first switching device K1 enters an off state under the action of the output signal of the trigger comparison circuit 30 or the off signal output by the delay comparison circuit 50. In this state, the coil of the relay J0 loses power, and the switch of the relay J0 is disconnected, so as to cut off the charging circuit. The third power supply can be a power supply different from the first power supply and the second power supply, or can be the same power supply as the first power supply and / or the second power supply, and the specific power supply is not limited.

[0099] The above scheme, the first switch circuit 40 comprises a first switching device K1 and a relay J0, and the relay J0 is used to realize the on-off control of the charging circuit, so as to have high reliability of the on-off control of the charging circuit.

[0100] Please refer to Figure 8 In some embodiments, the signal processing circuit 20 comprises a rectifier circuit 21, and the acquisition circuit 10 is connected to the first input end of the trigger comparison circuit 30 through the rectifier circuit 21.

[0101] Specifically, the rectifier circuit 21, i.e. a circuit for converting alternating current into direct current, converts the negative half cycle or the positive half cycle of the alternating current signal into a direct current signal of the same direction by using the unidirectional conduction characteristic of an electronic element (usually a diode D). Therefore, whether it is a forward surge signal or a reverse surge signal, it can be converted into a forward signal by rectification, so as to realize the trigger comparison of overcurrent.

[0102] The above scheme uses the rectifier circuit 21 to process the forward surge signal and the reverse surge signal, so as to obtain a forward signal that can reasonably represent the size of the surge signal, and improve the trigger accuracy of the overcurrent comparison circuit 53.

[0103] It can be understood that in another embodiment, the signal processing circuit 20 can also be formed by logic gates and inverters. When the forward surge signal is input, the state can be kept unchanged by the structure, and when the reverse surge signal is input, the output can be performed after being reversed by the structure.

[0104] Please refer to Figure 9 In order to facilitate the understanding of the technical scheme of the present application, the present application will be explained and described in detail in combination with the embodiments.

[0105] The reference voltage source is the reverse input end of the second comparator Q2 of the trigger comparison circuit 30, and provides a stable reference voltage. The current transformer is arranged in the charging circuit, and can monitor the surge of the charging circuit in real time. When the surge occurs, the current transformer collects the forward surge or the reverse surge, and sends it to the rectifier circuit 21 for processing, converts it into a forward signal, and transmits it to the forward input end of the second comparator Q2 for comparison with the reference voltage.

[0106] If the voltage value of the forward signal is greater than the reference voltage, at this time the second comparator Q2 outputs a high level signal, which represents the trigger of the overcurrent protection. Under the action of the high level signal, the second switch circuit 51 of the delay comparison circuit 50 is switched from the off state to the on state, and the electric energy of the first power supply flows into the charging circuit 52 through the second switch circuit 51, and charges the second capacitor C2 and the third capacitor C3 of the charging circuit 52. If the overcurrent protection is triggered continuously during the charging process, the voltage value of the forward input end of the first comparator Q1 of the comparison circuit 53 in the input delay comparison circuit 50 will gradually increase. When the charging time (delay time) reaches the preset delay time length, the voltage value of the forward input end of the first comparator Q1 is greater than the voltage value input by the reverse input end, which is the voltage value of the second power supply after being divided by the adjustable voltage dividing circuit 54. The first comparator Q1 outputs a high level signal.

[0107] Under the action of the high level signal outputted by the first comparator Q1, the first switching device K1 of the first switching circuit 40 is switched from the on state to the off state, the loop between the coil of the relay J0 and the power supply is disconnected, the relay J0 loses power, the switch of the relay J0 is turned off, and finally the charging loop is cut off.

[0108] The application further provides a battery management system comprising the charging loop and the protection device.

[0109] Specifically, the structure and implementation of the protection device are as shown in the above embodiments and the accompanying drawings, which will not be repeated here. The battery management system can collect the forward surge signal and the reverse surge signal of the charging loop in real time through the acquisition circuit 10, and can convert the forward surge signal and the reverse surge signal into a forward electric signal suitable for comparison through the signal processing circuit 20 and output to the trigger comparison circuit 30 for comparison with the voltage of the reference voltage source. If the voltage of the forward electric signal is greater than the voltage of the reference voltage source, it is determined that the overcurrent protection is triggered. At this time, under the action of the output signal of the trigger comparison circuit 30, the first switching circuit 40 will trigger and cut off the charging loop to interrupt the charging operation. Through this scheme, the overcurrent protection can be triggered no matter whether the forward surge signal or the reverse surge signal appears in the charging loop, and the operation reliability of the overcurrent protection is improved.

[0110] The application further provides a battery device comprising a battery and the battery management system.

[0111] Specifically, in the battery management system, the structure and implementation of the protection device are as shown in the above embodiments and the accompanying drawings, which will not be repeated here. The battery device can collect the forward surge signal and the reverse surge signal of the charging loop in real time through the acquisition circuit 10, and can convert the forward surge signal and the reverse surge signal into a forward electric signal suitable for comparison through the signal processing circuit 20 and output to the trigger comparison circuit 30 for comparison with the voltage of the reference voltage source. If the voltage of the forward electric signal is greater than the voltage of the reference voltage source, it is determined that the overcurrent protection is triggered. At this time, under the action of the output signal of the trigger comparison circuit 30, the first switching circuit 40 will trigger and cut off the charging loop to interrupt the charging operation. Through this scheme, the overcurrent protection can be triggered no matter whether the forward surge signal or the reverse surge signal appears in the charging loop, and the charging safety of the battery device is improved.

[0112] The application further provides a vehicle comprising a driving assembly and the battery device.

[0113] Specifically, in the battery device, the structure and implementation manner of the protection device are as shown in the above various embodiments and the drawings, and will not be described here. The vehicle can collect the forward surge signal and the reverse surge signal of the charging circuit in real time through the collection circuit 10, and no matter whether it is the forward surge signal or the reverse surge signal, it can be converted into a forward electric signal suitable for comparison through the signal processing circuit 20 and output to the trigger comparison circuit 30 for comparison with the voltage of the reference voltage source. If the voltage of the forward electric signal is greater than the voltage of the reference voltage source, it is determined that the overcurrent protection is triggered. At this time, under the action of the output signal of the trigger comparison circuit 30, the first switch circuit 40 will trigger the action to cut off the charging circuit and interrupt the charging operation. Through this scheme, no matter whether the forward surge signal or the reverse surge signal appears in the charging circuit, the overcurrent protection can be triggered, and the charging safety of the vehicle is improved.

[0114] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. Especially, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A protection device, characterized in that The application relates to a protection device for a charging circuit. The protection device comprises a collection circuit arranged in the charging circuit, which is used for capturing a forward surge signal and a reverse surge signal of the charging circuit; a signal processing circuit connected to the collection circuit, which is used for converting the forward surge signal or the reverse surge signal into a forward electric signal and outputting the same; a trigger comparison circuit, a first input end of which is connected to the signal processing circuit, and a second input end of which is used for connecting a reference voltage source; the trigger comparison circuit is used for triggering overcurrent protection when the voltage of the forward electric signal is greater than the voltage of the reference voltage source; a first switch circuit arranged in the charging circuit and connected to the output end of the trigger comparison circuit; the first switch circuit is used for cutting off the charging circuit when the trigger comparison circuit triggers overcurrent protection. The protection device further comprises a delay comparison circuit, the output end of the trigger comparison circuit is connected to the first switch circuit through the delay comparison circuit; the delay comparison circuit is used for starting a delay function when the trigger comparison circuit triggers overcurrent protection, and outputting a cut-off signal to the first switch circuit when the trigger comparison circuit maintains triggering overcurrent protection within a preset delay time length; the first switch circuit is used for cutting off the charging circuit when the cut-off signal is received. The delay comparison circuit comprises a second switch circuit, a charging circuit and a comparison circuit, the control end of the second switch circuit is connected to the output end of the trigger comparison circuit, the input end of the second switch circuit is connected to the power supply end of the comparison circuit, the power supply end of the comparison circuit is used for connecting a first power supply, the output end of the second switch circuit is connected to the charging circuit, the charging circuit is connected to the first input end of the comparison circuit, the second input end of the comparison circuit is used for connecting a second power supply, and the output end of the comparison circuit is connected to the first switch circuit. The delay comparison circuit further comprises an adjustable voltage dividing circuit, and the second input end of the comparison circuit is connected to the second power supply through the adjustable voltage dividing circuit. The charging circuit comprises a first capacitor, the output end of the second switch circuit is connected to the first end of the first capacitor, and the second end of the first capacitor is connected to the first input end of the comparison circuit.

2. The protection device according to claim 1, characterized in that The charging circuit comprises a second capacitor, a third capacitor and a diode, the output end of the second switch circuit is connected to the first end of the second capacitor and the anode of the diode, the cathode of the diode is connected to the first end of the third capacitor and the first input end of the comparison circuit, and the second end of the second capacitor and the second end of the third capacitor are grounded.

3. The protection device according to claim 2, characterized in that The second capacitor comprises an adjustable capacitor, and / or the third capacitor comprises an adjustable capacitor.

4. The protection device according to claim 3, characterized in that ​ 5. Protection according to claim 3 or 4, characterized in that ​ 6. Protection according to claim 3 or 4, characterized in that ​ 7. The protection device according to claim 6, characterized in that ​ 8. The protection device according to claim 3 or 4, characterized in that The comparison circuit comprises a first comparator and a first current-limiting resistor, a power supply end of the first comparator is connected with the first power supply and an input end of the second switch circuit, a first input end of the first comparator is connected with the charging circuit, a second input end of the first comparator is used for connecting the second power supply, a ground end of the first comparator is grounded, and an output end of the first comparator is connected with the first switch circuit through the first current-limiting resistor.

9. The protection device according to any one of claims 1 to 4, characterized in that The trigger comparison circuit comprises a second comparator and a second current-limiting resistor, a first input end of the second comparator is connected with the signal processing circuit, a second input end of the second comparator is used for connecting the reference voltage source, and an output end of the second comparator is connected with the first switch circuit through the second current-limiting resistor.

10. The protection device according to any one of claims 1 to 4, characterized in that The first switch circuit comprises a first switch device and a relay, a control end of the first switch device is connected with an output end of the trigger comparison circuit, an input end of the first switch device is connected with a first end of a coil of the relay, a second end of the coil of the relay is used for connecting a third power supply, an output end of the first switch device is grounded, and a switch of the relay is connected in series with the charging loop.

11. The protection device according to any one of claims 1 to 4, characterized in that The signal processing circuit comprises a rectifier circuit, and the acquisition circuit is connected with a first input end of the trigger comparison circuit through the rectifier circuit.

12. A battery management system, characterized by, The battery management system comprises a battery and the protection device according to any one of claims 1-11.

13. A battery device characterized by comprising: The battery device comprises a battery and the battery management system according to claim 12.

14. A vehicle characterized by comprising: The battery device comprises a battery and the battery management system according to claim 12.

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