LOCKING CONTROL DEVICE FOR BATTERY MANAGEMENT SYSTEM AND BATTERY MANAGEMENT SYSTEM EQUIPPED WITH SUCH A DEVICE

Abstract

The invention relates to a locking control device (5) for a battery management system (3), said device comprising at least: – a memory stage (7) for abnormal battery operating conditions, said stage being configured, on the one hand, to receive as input one or more voltages (VUV, VOV, VT) relating to abnormal operating conditions, and on the other hand, to permanently store the occurrence of an abnormal battery operating condition; – a locking control stage (9) whose input is connected to the output of said memory stage (7) and whose output is configured to be connected to said battery management system (3), said control stage (7) being configured to send a locking command to said battery management system (9) if an abnormal operating condition is stored in said memory stage (7).Figure to be published with the abbreviation: [Fig. 2].

Description

Title of the invention: LOCK CONTROL DEVICE FOR BATTERY MANAGEMENT SYSTEM BATTERY MULATORS AND BATTERY ACCUMULATOR MANAGEMENT SYSTEM EQUIPPED WITH SUCH A DEVICE

[0001] The technical context of the present invention is that of electric batteries, and in particular batteries with high electric current, in particular greater than 50 A, and preferably greater than 500 A, for example for aeronautical and / or aerospace applications. More particularly, the invention relates to a locking control device for a system for managing such batteries.

[0002] A battery generally comprises several battery modules, generally formed of several accumulators or cells, forming an assembly which can also be connected to an external bus allowing data to be sent to a supervision system, a system generally referred to as a battery accumulator management system (or “Battery Management System” in English).

[0003] The battery accumulator management system is notably configured to measure various physical quantities relating to the battery, the modules and / or battery cells, such as voltages, currents, temperatures, internal resistances, etc., but also includes protection circuits to prevent the battery from operating under abnormal operating conditions, conditions which may damage the battery and cause human and / or material damage.

[0004] Abnormal operating conditions are generally understood to mean: overvoltages, overcurrents, undervoltages, excessively high battery temperature, short circuits, etc., i.e. all parameters which do not correspond to a nominal operating range of the battery.

[0005] The accumulator management systems thus comprise safety devices, such as a disconnecting device configured to cut the electrical connections of the battery with the outside (and therefore electrically isolate it) in the event that abnormal operating conditions occur.

[0006] However, once the disconnecting device associated with the battery has tripped, rendering the battery inoperative, there is nothing to prevent the disconnecting device from being reset and the battery from being used again, regardless of any checking and / or testing of the battery.

[0007] It is therefore necessary to provide security which prevents any use of said battery due to an abnormal operating condition, until the battery is checked and it is certain that it is safe to use.

[0008] The present invention thus proposes to remedy at least one of the aforementioned drawbacks by proposing a new type of locking control device for a battery accumulator management system, said device comprising at least: - a stage for storing abnormal operating conditions of the battery, said stage being configured, on the one hand, to receive as input one or more voltages relating to abnormal operating conditions, and on the other hand, to permanently store the occurrence of an abnormal operating condition of the battery; - a locking control stage whose input is connected to the output of said storage stage and whose output is configured to be connected to said battery accumulator management system; said control stage being configured to send a locking command to said battery accumulator management system if an abnormal operating condition is stored in said storage stage.

[0009] It will be noted that here by battery is meant the battery as a whole, or one or more of its sub-elements, i.e. an accumulator or battery cell, or several accumulators, or cells, connected in series and / or in parallel. It will also be noted that by "permanent storage" is meant the fact that the device according to the invention, and more particularly the storage stage, is configured to retain a state, and therefore the information, independently of an electrical power supply (or another physical parameter), the information therefore being able to be retained for a long time regardless of the environment in which the battery is located.

[0010] The locking control device according to the invention makes it possible to memorize certain abnormal operating conditions of the battery, in particular by being connected to electrical quantities, here voltages, reflecting an overvoltage, an undervoltage and / or an abnormal temperature (too high or too low), and to control the locking of the battery via the battery accumulator management system. Once the battery is locked, it is rendered inoperative and cannot be used, no action can be performed by it, such as a current draw. The device according to the invention thus guarantees that the battery, whatever the fault that caused it to be blocked, cannot present a danger to an operator or equipment to which the battery is connected.

[0011] According to a possible characteristic, said storage stage comprises a disconnection member configured to store an abnormal operating condition of the battery. The memorization of an abnormal operating condition of the battery is therefore carried out by means of the disconnection, for example irreversible, or not of a disconnecting member. Such a disconnecting member is advantageously a fuse, for example of the blade type, with a transparent glass tube, etc. or a circuit breaker, preferably non-resettable, or inaccessible to the user of the battery if it is resettable.

[0012] According to another possible characteristic, said disconnecting member is configured to permanently store an abnormal operating condition of the battery. Advantageously, said disconnecting member thus passes from one physical state to another irreversibly following an abnormal operating condition of the battery.

[0013] According to another possible characteristic, said disconnecting member is configured to disconnect if an input voltage of the storage stage is greater than or equal to a predetermined value. The predetermined value triggering the storage of an abnormal operating condition is chosen in such a way as to avoid the tripping of the circuit breaker following fluctuations in the input voltages.

[0014] According to another possible characteristic, said storage stage comprises at least one switch configured to trigger the disconnection of said disconnection member as a function of the input voltage of said storage stage.

[0015] According to another possible characteristic, said at least one switch is a transistor, for example of the MOSFET type. Advantageously, said switch is a MOSFET transistor, for example of type N, allowing voltage control of the triggering of the disconnecting member, and therefore the memorization of an abnormal operating condition of the battery.

[0016] According to another possible characteristic, said storage stage is configured to deliver as output: - a first voltage value if the disconnecting device has not stored an abnormal operating condition; - a second voltage value if the disconnecting device has memorized an abnormal operating condition; said control stage being configured to send a locking command to said battery accumulator management system if the control stage receives the second voltage value as input.

[0017] According to another possible characteristic, said control stage comprises at least one operational amplifier mounted as a comparator. Said control stage advantageously comprises an operational amplifier mounted as a comparator, for example an inverter, making it possible, depending on the state of the disconnecting member, to deliver an output signal triggering or not the locking of the battery by the battery accumulator management system.

[0018] The invention also relates to a system for managing battery accumulators, characterized in that said system comprises a locking control device as defined above.

[0019] The invention further relates to an electric battery, advantageously for aeronautical and / or aerospace applications, characterized in that said battery comprises a battery accumulator management system as defined above.

[0020] Other characteristics and advantages of the invention will become apparent from the following description on the one hand, and from several examples of embodiment given for informational and non-limiting purposes with reference to the attached schematic drawings on the other hand, in which: - [Fig.l] illustrates a very schematic and side view of an electric battery equipped with a battery accumulator management system; - [Fig.2] illustrates a schematic view of a locking control device according to the invention; - [Fig. 3] is a schematic, enlarged and detailed view of the device of [Fig. 2].

[0021] Of course, the characteristics, variants and different embodiments of the invention may be associated with each other, in various combinations, to the extent that they are not incompatible or mutually exclusive. In particular, variants of the invention may be imagined comprising only a selection of characteristics described below in isolation from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention from the prior art.

[0022] In particular, all the variants and all the embodiments described can be combined with each other if nothing prevents this combination from a technical point of view. Furthermore, in the different figures, the elements common to several figures retain the same reference.

[0023] [Fig.l] illustrates a very schematic and functional view of an electric battery 1, for example a lithium-ion battery advantageously intended for aeronautical or aerospace applications, which comprises battery accumulators 2 (or cells), a battery accumulator management system 3 connected to said accumulators, system 3 also designated by the English acronym “BMS” for “Battery Management System”, as well as a communication circuit 4 connected to said management system 3 and configured to allow the system 3 to exchange information. training with the outside (information relating to the environment, the battery, the aircraft, etc.), for example with a computer, a server, a sensor, etc.

[0024] Said management system 3 is generally integrated into said battery 1, in order to monitor the various physical or electrical quantities characteristic of a battery 1, and / or of its accumulators 2 (or cells), for example a voltage, an internal resistance, etc.

[0025] Said management system 3 is also configured to prevent the operation of the battery 1 outside its nominal operating range, that is to say that the system is configured to detect abnormal operating conditions of the battery (or of one or more of its cells), such as an overcurrent, an overvoltage (in particular during its charging), an undervoltage (in particular during its discharging), an overheating, etc.

[0026] Such a system 3 may also comprise a locking circuit (not shown) configured to prevent the use of the battery 1, and therefore its operation, in particular if an abnormal operating condition has previously occurred.

[0027] [Fig.2] thus illustrates a diagram of the locking control device 5 of the locking circuit, activation of said locking circuit causing the electrical disconnection of the battery 1, in order to protect it from possible damage. The locking circuit comprises for example an electromechanical or semiconductor relay.

[0028] Said device 5 thus comprises at least: - a stage 7 for storing abnormal operating conditions of the battery, said stage 7 being configured, on the one hand, to receive as input one or more voltages Vuv, Vov, VT relating to abnormal operating conditions of the battery 1 (or one or more of its cells 2), and on the other hand, to permanently store the occurrence of an abnormal operating condition of the battery 1; - a locking control stage 9 whose input is connected to the output of said storage stage 7 and whose output is configured to be connected to said battery accumulator management system 3, and more particularly to the locking circuit.

[0029] It will be noted that by battery is meant the battery 1 as a whole, or one or more of its sub-elements, that is to say a single accumulator 2, or battery cell, or even several accumulators 2, or cells, connected in series and / or in parallel.

[0030] Thus, the storage stage 7 is connected to circuits delivering voltages representing different abnormal operating conditions of said battery and / or of its modules, these circuits being for example integrated into said management system 3. There are advantageously three voltages reflecting abnormal conditions, respectively linked to an undervoltage Vuv, to an overvoltage Vov and / or a temperature problem VT (i.e. an excess temperature or a temperature that is too low).

[0031] Thus, as soon as one of the input voltages Vuv, Vov, VT exceeds a threshold value, previously determined (here a value common to said voltages), indicative of an abnormal operating condition, then there is permanent storage of this state by said storage stage 7.

[0032] Furthermore, said control stage 9 is configured to send a locking command (or signal) Sv to said management system 3, when the storage stage 7 has stored an abnormal operating condition.

[0033] [Fig. 3] is an enlarged and detailed schematic view of the locking control device 5, and in particular of the storage stages 7 and locking control stages 9.

[0034] Thus, the storage stage 7 comprises at least: - an input resistor Ri, called the first resistor, and a second resistor R2 mounted as a divider bridge, said bridge being supplied with voltage by one or more of the input voltages Vuv, Vov, VT relating to an abnormal operating condition of the battery 1; - a disconnecting member Fi configured to memorize an abnormal operating condition of the battery and powered by a direct voltage VCc, advantageously via a current limiting resistor RL1; - a MOSFET type transistor T i having a gate, a source and a drain, the gate of the transistor being supplied by one or more input voltages Vuv, Vov, VT, this via the divider bridge formed by the first and second resistors Ri and R2, the source being connected to a ground G (by the ground of the management system 3), while the drain is supplied by the DC voltage Vœ via the disconnecting member Fi; - a storage stage output 7 which is connected to a node ND, or drain node, located between the fuse Fi and the drain of the transistor Ti and which connects the storage stage 7 to the input of the locking control stage 9.

[0035] The storage stage 7 further advantageously comprises: - a capacitor Ci, called the first capacitor, mounted in parallel with the second resistor R2, and forming a parallel RC circuit which is connected, on the one hand, between the first resistor Ri and the gate of the transistor Ti, and on the other hand, to ground G; - a resistor R3, called the third resistor, and a resistor R4, called the fourth resistor, forming another divider bridge which is connected to the drain node ND and to the input of the control stage 9; - a capacitor C2, called the second capacitor, connected in parallel with the fourth resistor R4, and thus forming a parallel RC circuit, an RC circuit connected, on the one hand, to the drain node ND, via the third resistor R3, and on the other hand, to ground G.

[0036] More particularly, it will be noted that the first divider bridge formed by the first and second resistors Ri and R2, and the parallel RC circuit, formed by the second resistor R2 and the first capacitor Ci, respectively make it possible to reduce the voltage applied to the gate of the transistor Ti (for example to 0.33 V), and to allow a progressive increase in the voltage applied to the gate of the transistor Ti (thus avoiding an overvoltage which could damage it).

[0037] The second divider bridge formed by the third and fourth resistors R3 and R4 makes it possible, among other things, to limit the output voltage of the storage stage 7 which supplies the inverting input of the operational amplifier AOi.

[0038] More particularly, said disconnecting member Fi is advantageously a fuse, for example of the blade type, transparent glass tube, etc. or a circuit breaker, preferably non-resettable, or inaccessible to the user of the battery 1 if it is resettable. Thus, said disconnecting member Fi is configured to permanently store an abnormal operating condition of the battery, by passing from one physical state to another irreversibly.

[0039] It will be noted that permanent storage and irreversible change of state are understood to mean that the disconnecting member Fi is not configured to return to its initial state spontaneously, for example when there is no longer any electrical power supply.

[0040] Thus, if said disconnecting member is configured to change state if an input voltage Vuv, Vov, VT of the storage stage 7 is greater than or equal to a predetermined value.

[0041] The transistor Ti, for its part, acts as a switch configured to trigger the disconnection of said disconnection member as a function of the value of the input voltages V uv, Vov, VT of said storage stage 7 (in particular when one of these voltages exceeds the predetermined value).

[0042] Indeed, the voltage between the drain and the source of the transistor Ti is fixed by the DC voltage VCc, whereas as a function of the gate voltage of the transistor Ti depending on the value of the input voltages Vuv, Vov, VT, the value of the current passing through the disconnection member Fi causes its disconnection when the value of the input voltages Vuv, Vov, VT exceeds the predetermined threshold value.

[0043] Thus, said storage stage 7 is configured to deliver as output: - a first voltage value VN if the circuit breaker Fi has not stored an abnormal operating condition; - a second voltage value VA if the Fi circuit breaker has stored an abnormal operating condition.

[0044] The locking control stage 9 comprises, for its part, at least one operational amplifier AOi mounted as a comparator. Said operational amplifier AOi has an inverting input, a non-inverting input, as well as an output connected to said locking circuit of the management system 3.

[0045] The inverting input of said operational amplifier AOi is connected to the output of the storage stage 9, while the non-inverting input is supplied by a reference voltage VRu and is connected to ground G, for example via a capacitor C3, called the third capacitor. It will be noted that this third capacitor C3 has the particular purpose of reducing the input impedance of the non-inverting input of the operational amplifier AOp

[0046] The output of the operational amplifier AOi corresponds, for its part, to the output of the control stage 9 and is therefore connected to the locking circuit of said management system 3.

[0047] The operational amplifier AOi, mounted here as an inverting comparator, allows, depending on the state of the disconnecting member Fi, to deliver an output signal Sv triggering or not the locking of the battery 1 by the management system 3 of the battery accumulators.

[0048] Thus, if the output voltage of the storage stage 7 corresponds to the first voltage value VN then this is higher than the reference voltage VREF, and the output voltage is -VSAT, a voltage value which does not trigger the locking of the battery 1. Whereas if the output voltage of the storage stage 7 corresponds to the second voltage value VA then this is lower than the reference voltage VREF, and the output voltage is +VSAT of the control stage 9. This voltage value +VSAT is identified with the locking signal Sv and therefore triggers the locking of the battery 1 by the locking circuit.

[0049] It will be noted that the control stage 9 can also be configured so that the locking signal Sv corresponds to another voltage value, for example with an operational amplifier AOi mounted as a non-inverting comparator, as long as the management system 3 is configured accordingly.

[0050] In other variant embodiments of the invention not shown, the device 5 does not comprise resistors R2, R3 and / or R4 respectively forming a divider bridge at the input and output of the storage stage 7, for example because the input voltages Vuv, Vov, VT (and following) have voltage values ​​compatible with the different electronic components of the device 5 or because a voltage step-down circuit is arranged upstream of said storage stage 7.

Claims

Claims

1. Lock control device (5) for a battery accumulator management system (3), said device comprising at least: - a storage stage (7) for abnormal battery operating conditions, said stage being configured, on the one hand, to receive as input one or more voltages (Vuv, Vov, VT) relating to abnormal operating conditions, and on the other hand, to permanently store the occurrence of an abnormal battery operating condition; - a locking control stage (9) whose input is connected to the output of said storage stage (7) and whose output is configured to be connected to said battery accumulator management system (3), said control stage (7) being configured to send a locking command to said battery accumulator management system (9) if an abnormal operating condition is stored in said storage stage (7).

2. Device (5) according to the preceding claim, characterized in that said storage stage (7) comprises a disconnection member (FJ) configured to store an abnormal operating condition of the battery.

3. Device (5) according to the preceding claim, characterized in that said disconnecting member (Fi) is configured to permanently store an abnormal operating condition of the battery.

4. Device (5) according to the preceding claim, characterized in that said disconnecting member (Fi) is configured to disconnect if an input voltage (Vuv, Vov, VT) of the storage stage (7) is greater than or equal to a predetermined value.

5. Device (5) according to any one of the preceding claims, characterized in that said storage stage (7) comprises at least one switch (Ti) configured to trigger the disconnection of said disconnection member (FJ) as a function of the input voltage (Vuv, Vov, VT) of said storage stage (7).

6. Device (5) according to the preceding claim, characterized in that said at least one switch (Ti) is a MOSFET type transistor.

7. Device (5) according to any one of the preceding claims, characterized in that said storage stage (7) is configured to deliver as output: - a first voltage value (VN) if the disconnecting member (FJ) has not stored an abnormal operating condition; - a second voltage value (VA) if the disconnecting member (FJ) has stored an abnormal operating condition; said control stage (9) being configured to send a locking command to said battery accumulator management system (3) if the control stage (9) receives the second voltage value (VA) as input.

8. Device (5) according to any one of the preceding claims, characterized in that said control stage (9) comprises at least one operational amplifier (AOi) mounted as a comparator.

9. Battery accumulator management system (3), characterized in that said system (3) comprises a locking control device (5) according to any one of the preceding claims.

10. Electric battery (1), characterized in that said battery comprises a management system (3) of the battery accumulators according to the preceding claim.

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