Control method of driving system, driving system and vehicle

Abstract

The invention provides a control method of a driving system, the driving system and a vehicle, and the control method of the driving system comprises the steps: when one of a first battery pack and a second battery pack breaks down, controlling a second electric control unit to receive the voltage provided by a non-fault battery pack; wherein the non-fault battery pack is a non-fault battery pack in the first battery pack and the second battery pack; controlling the second electric control unit to boost the voltage provided by the non-fault battery pack into a preset voltage, and providing the preset voltage to at least one of the n first electric control units; and controlling at least one first electric control unit to drive the corresponding motor to operate according to the preset voltage. According to the control method, the reliability of the driving system can be improved, and the safety of the vehicle can be improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a control method of a drive system, a drive system and a vehicle. Background Art

[0002] In the high-voltage system of electric vehicles, a battery pack is generally composed of multiple single cells connected in series and parallel to provide power for the vehicle. If the battery pack voltage does not reach the normal working voltage of the electronic control due to an abnormality, the electronic control recognizes that the voltage has not reached the set working voltage value, an undervoltage fault occurs, and the high-voltage load loses energy and cannot work, causing the vehicle to break down. However, if only a single cell has overtemperature, overvoltage, overdischarge, low temperature and other faults, the entire battery pack will also report a fault, causing the vehicle to break down and suddenly lose power, posing a huge safety hazard. In addition, if a single cell fails in a location far away from the car after-sales store, the tow truck cannot provide rescue in a short time, which will bring a poor experience to customers. Summary of the invention

[0003] In order to solve the above technical problems or at least partially solve the above technical problems, the present application provides a control method of a drive system, a drive system and a vehicle.

[0004] To achieve the above-mentioned object, the first aspect of the present application provides a control method of a drive system, the control method of the drive system comprising:

[0005] When a battery pack in the first battery pack and the second battery pack fails, the second electronic control unit is controlled to receive a voltage provided by a non-faulty battery pack; wherein the non-faulty battery pack is a battery pack in the first battery pack and the second battery pack that has not failed;

[0006] controlling the second electronic control unit to boost the voltage provided by the non-faulty battery pack to a preset voltage and provide the voltage to at least one of the n first electronic control units; and

[0007] Controlling at least one of the first electronic control units to drive a corresponding motor to operate according to a preset voltage;

[0008] Wherein, the driving system comprises:

[0009] A power battery, comprising a first battery group and a second battery group, wherein a negative electrode of the first battery group is electrically connected to a positive electrode of the second battery group;

[0010] n first electronic control units; wherein n is an integer and n≥1; and

[0011] The second electronic control unit.

[0012] The control method of the drive system provided in the present application controls the second electronic control unit to receive the voltage provided by the non-faulty battery pack, and controls the second electronic control unit to boost the voltage provided by the non-faulty battery pack to a preset voltage when one of the first battery pack and the second battery pack fails, so that at least one of the n first electronic control units can operate normally. In this way, the problem of the vehicle suddenly breaking down and losing power due to the failure of a single battery cell can be avoided, the reliability of the drive system can be improved, and the safety of the vehicle can be improved.

[0013] In some embodiments, controlling the second electronic control unit to receive the voltage provided by the non-faulty battery pack includes:

[0014] Controlling the first switch to be turned on so that the second electronic control unit receives the voltage provided by the non-faulty battery pack;

[0015] The second electronic control unit includes a motor and a first switch, a first end of the first switch is electrically connected to the motor in the second electronic control unit, and a second end of the first switch is electrically connected to both the negative electrode of the first battery pack and the positive electrode of the second battery pack.

[0016] In some embodiments, before controlling the second electric control unit to receive the voltage provided by the non-faulty battery pack, the control method of the drive system further includes:

[0017] When a battery pack of the first battery pack and the second battery pack fails, controlling the second switch in the non-faulty battery pack to be turned on, and controlling the second switch in the faulty battery pack to be turned off;

[0018] Wherein, the first battery pack and the second battery pack both include a single battery cell and a second switch, and the single battery cell and the second switch are connected in series.

[0019] In some embodiments, the step of controlling the second electronic control unit to boost the voltage provided by the non-faulty battery pack to a preset voltage and provide the voltage to at least one of the n first electronic control units includes:

[0020] According to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack, the upper tube and the lower tube of the target bridge arm in the second electronic control unit are controlled to be turned on alternately at a preset frequency, so that the target bridge arm and the target winding in the second electronic control unit form a boost circuit to boost the voltage provided by the non-faulty battery pack to a preset voltage, and provide the voltage to at least one of the n first electronic control units;

[0021] Among them, the second electronic control unit includes a motor and an inverter, the inverter includes at least one bridge arm connected in parallel between the positive pole of the first battery group and the negative pole of the second battery group, the bridge arm includes an upper tube, a lower tube and a midpoint, at least one phase winding of the motor is electrically connected to the midpoint of at least one bridge arm in the inverter in a one-to-one correspondence; the target bridge arm is at least one bridge arm of the inverter of the second electronic control unit, and the target winding is a winding in the motor of the second electronic control unit that is electrically connected to the target bridge arm.

[0022] In some embodiments, the controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack includes:

[0023] deriving a target duty cycle according to a rated voltage of a faulty battery pack and a rated voltage of a non-faulty battery pack;

[0024] According to the target duty cycle, generating a first control signal and a second control signal, both of which have a preset frequency; wherein the duty cycle of the first control signal is the target duty cycle, and the second control signal is inverted with the first control signal; and

[0025] According to the fault conditions of the first battery pack and the second battery pack, the first control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the second control signal is output to the lower tube of the target bridge arm in the second electronic control unit, or the second control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the first control signal is output to the lower tube of the target bridge arm in the second electronic control unit, thereby controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency.

[0026] In some embodiments, the step of obtaining a target duty cycle according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack includes:

[0027] The target duty cycle is calculated according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack according to a preset duty cycle calculation formula; wherein the preset duty cycle calculation formula is D1=Ub / (Ua+Ub), D1 is the target duty cycle, Ua is the rated voltage of the non-faulty battery pack, and Ub is the rated voltage of the faulty battery pack.

[0028] In some embodiments, according to the fault conditions of the first battery pack and the second battery pack, the first control signal is output to the upper tube of the target bridge arm in the second electric control unit and the second control signal is output to the lower tube of the target bridge arm in the second electric control unit, or the second control signal is output to the upper tube of the target bridge arm in the second electric control unit and the first control signal is output to the lower tube of the target bridge arm in the second electric control unit, so as to control the upper tube and the lower tube of the target bridge arm in the second electric control unit to be alternately turned on at a preset frequency, including:

[0029] When the first battery pack fails, the second control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the first control signal is output to the lower tube of the target bridge arm in the second electronic control unit, so as to control the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency; and

[0030] When a fault occurs in the second battery pack, the first control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the second control signal is output to the lower tube of the target bridge arm in the second electronic control unit, thereby controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency.

[0031] In some embodiments, the control method of the drive system further includes:

[0032] Obtaining status information of a single cell; and

[0033] According to the status information of the single battery cells, it is determined that one of the first battery group and the second battery group fails.

[0034] A second aspect of the present application further provides a drive system, the drive system comprising:

[0035] A power battery, the power battery comprising a first battery group and a second battery group, wherein the negative electrode of the first battery group is electrically connected to the positive electrode of the second battery group;

[0036] n first electronic control units; wherein n is an integer, n≥1;

[0037] a second electronic control unit; and

[0038] The controller is electrically connected to the n first electric control units and the second electric control unit, and is used to execute the control method of the drive system described in the first aspect above.

[0039] A third aspect of the present application further provides a vehicle, the vehicle comprising:

[0040] the vehicle body; and

[0041] The drive system described in the second aspect above; wherein, the drive system is arranged in the vehicle body.

[0042] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a topological schematic diagram of a drive system provided in an embodiment of the present application;

[0044] Figure 2 yes Figure 1 The circuit structure diagram of the driving system shown;

[0045] Figure 3 is a flow chart of a control method of a drive system provided in an embodiment of the present application;

[0046] Figure 4 yes Figure 2 A schematic diagram of current flow in the drive system shown;

[0047] Figure 5 yes Figure 2 Another current flow diagram of the drive system shown;

[0048] Figure 6 It is a schematic diagram of the topological structure of a vehicle provided in an embodiment of the present application.

[0049] The following are the descriptions of the reference numerals:

[0050] Drive system 100

[0051] Power battery 1

[0052] The first battery pack 11

[0053] Second battery pack 12

[0054] First electronic control unit 3

[0055] Second electronic control unit 2

[0056] DC charging port 4

[0057] Inverter 21

[0058] AC port 212

[0059] DC Port 211

[0060] Motor 22

[0061] First switch K1

[0062] Second switch K2

[0063] The third switch K3

[0064] The fourth switch K4

[0065] Upper tube T1, T2, T3

[0066] Down tube T4, T5, T6

[0067] A phase winding WA

[0068] B phase winding WB

[0069] C phase winding WC

[0070] Capacitors C1, C2

[0071] Vehicle 1000

[0072] Vehicle body 200

[0073] The following specific implementation methods will illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0074] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0075] In addition, the terms "first", "second", etc. in the specification of the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0076] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0077] Please also read Figure 1-2 , Figure 1 is a topological diagram of a drive system provided in an embodiment of the present application, Figure 2 yes Figure 1The circuit structure diagram of the driving system is shown.

[0078] like Figure 1-2 As shown, the drive system 100 includes a power battery 1, n first electronic control units 3 and a second electronic control unit 2. Where n≥1, Figure 1-2 In the illustrated embodiment, the driving system 100 is described with n=1. In other embodiments, n may also be other values, such as 2, 3, 4, etc.

[0079] The power battery 1 includes a first battery group 11 and a second battery group 12 , and a negative electrode of the first battery group 11 is electrically connected to a positive electrode of the second battery group 12 .

[0080] Each of the first electric control unit 3 and the second electric control unit 2 includes an inverter 21 and a motor 22. The inverter 21 includes an AC port 212 and a DC port 211. The DC port 211 is electrically connected to the positive electrode of the first battery pack 11 and the negative electrode of the second battery pack 12, and the AC port 212 is electrically connected to the corresponding motor 22. The neutral point of the motor 22 in the second electric control unit 2 is electrically connected to the negative electrode of the first battery pack 11 and the positive electrode of the second battery pack 12.

[0081] The AC port 212 is electrically connected to the corresponding motor 22 , which means that the AC port 212 is electrically connected to the motor 22 in the electric control unit.

[0082] Exemplarily, each of the first battery group 11 and the second battery group 12 may include one or more battery packs, wherein each battery pack may include at least one single battery cell.

[0083] Exemplarily, the motor 22 includes a drive motor or an air conditioning compressor. The motor 22 may be a single-phase motor or a multi-phase motor. Figure 2 Three-phase motor shown.

[0084] Under normal circumstances, both the first battery pack 11 and the second battery pack 12 have no faults. The first battery pack 11 and the second battery pack 12 are connected in series and provide an electronic control working voltage to the n first electronic control units 3 and the second electronic control unit 2. In this way, any one of the n first electronic control units 3 and the second electronic control unit 2 can operate based on the electronic control working voltage provided by the power battery 1. Specifically, when a certain electronic control unit is operating, the inverter 21 in the electronic control unit receives the electronic control working voltage provided by the power battery 1 through the DC port 211, and inverts the electronic control working voltage into an AC voltage, and provides the AC voltage to the motor 22 in the electronic control unit through the AC port 212 to drive the motor 22 to operate.

[0085] However, when a single cell in the power battery 1 fails due to over-temperature, over-voltage, over-discharge, or low temperature, causing the power battery 1 to be unable to provide the electronic control working voltage, each electronic control unit will detect that the received voltage cannot reach the electronic control working voltage and an under-voltage fault will occur, thereby stopping working. This will cause the vehicle to break down and suddenly lose power, posing a huge safety hazard. In addition, if a single cell fails in a location far away from an aftermarket, a tow truck cannot provide rescue in a short time, which will bring a poor experience to customers.

[0086] In view of this, the present application provides a control method for a drive system, please refer to Figure 3 , Figure 3 is a flow chart of a control method of a drive system provided in an embodiment of the present application, and the control method is applied to the drive system 100 described above.

[0087] like Figure 3 As shown, the control method of the driving system includes steps S1 to S3, which are specifically as follows:

[0088] Step S1 : when one of the first battery pack 11 and the second battery pack 12 fails, the second electric control unit 2 is controlled to receive the voltage provided by the non-faulty battery pack.

[0089] The non-faulty battery group is a battery group that has not failed in the first battery group 11 and the second battery group 12 .

[0090] Step S2 , controlling the second electronic control unit 2 to boost the voltage provided by the non-faulty battery pack to a preset voltage, and providing the voltage to at least one of the n first electronic control units 3 .

[0091] Step S3, controlling at least one of the first electronic control units 3 to drive the corresponding motor 22 to operate according to a preset voltage.

[0092] The voltage value of the preset voltage is equal to or close to the voltage value of the electronic control working voltage, so that the n first electronic control units 3 will not have an undervoltage fault when receiving the preset voltage and can operate normally.

[0093] The control method of the drive system provided in the present application controls the second electronic control unit 2 to receive the voltage provided by the non-faulty battery pack when one of the first battery pack 11 and the second battery pack 12 fails, and controls the second electronic control unit 2 to perform a boost function to boost the voltage provided by the non-faulty battery pack to a preset voltage, so that at least one of the n first electronic control units 3 can operate normally. In this way, the problem of the vehicle suddenly breaking down and losing power due to the failure of a single battery cell can be avoided, the reliability of the drive system 100 can be improved, and the safety of the vehicle can be improved.

[0094] like Figure 2 As shown, in some embodiments, the second electronic control unit 2 also includes a first switch K1, a first end of the first switch K1 is electrically connected to the neutral point of the motor 22 in the second electronic control unit 2, and a second end of the first switch K1 is electrically connected to the negative electrode of the first battery group 11 and the positive electrode of the second battery group 12.

[0095] The controlling the second electronic control unit 2 to receive the voltage provided by the non-faulty battery pack comprises:

[0096] The first switch K1 is controlled to be turned on, so that the second electronic control unit 2 receives the voltage provided by the non-faulty battery pack.

[0097] In this way, when both the first battery group 11 and the second battery group 12 are in good condition, the first switch K1 can be controlled to disconnect the electrical connection between the neutral point of the motor 22 in the second electronic control unit 2 and the power battery 1, so that the second electronic control unit 2 can perform the inverter function to invert the electronic control working voltage provided by the power battery 1 into AC power to drive the motor 22 to operate; when one of the first battery group 11 and the second battery group 12 fails, the first switch K1 can be controlled to connect the electrical connection between the neutral point of the motor 22 in the second electronic control unit 2 and the power battery 1, so that the second electronic control unit 2 can perform the boost function, thereby realizing the reuse of the second electronic control unit 2.

[0098] In some embodiments, the first battery pack 11 and the second battery pack 12 both include a single battery cell and a second switch K2 , and the single battery cell and the second switch K2 are connected in series.

[0099] Before controlling the second electric control unit 2 to receive the voltage provided by the non-faulty battery pack through the neutral point of the motor 22, the control method of the drive system further includes:

[0100] When a fault occurs in one of the first battery group 11 and the second battery group 12 , the second switch K2 in the non-faulty battery group is controlled to be turned on, and the second switch K2 in the faulty battery group is controlled to be turned off.

[0101] In this way, the faulty battery pack can be reliably disconnected through the second switch K2, thereby avoiding a short circuit fault.

[0102] In some embodiments, each of the first electric control unit 3 and the second electric control unit 2 further includes a capacitor C1, and the capacitor C1 is electrically connected to the DC port 211 of the inverter 21 in the electric control unit. The capacitor C1 is used to keep the voltage received by the DC port 211 of the electric control unit stable.

[0103] In some other embodiments, the second electronic control unit 2 and the n first electronic control units 3 may also share a bus capacitor with a larger capacitance value, without providing a separate capacitor C1 for each electronic control unit.

[0104] In some embodiments, the inverter 21 includes at least one bridge arm connected in parallel between the positive electrode of the first battery group 11 and the negative electrode of the second battery group 12, and each bridge arm includes an upper tube, a lower tube and a midpoint, and the first bus end of the upper tube of the at least one bridge arm and the second bus end of the lower tube of the at least one bridge arm constitute the DC port 211, and the midpoint of the at least one bridge arm constitutes the AC port 212. At least one phase winding of the motor 22 is electrically connected to the midpoint of at least one bridge arm in the corresponding inverter 21 in a one-to-one correspondence.

[0105] The controlling the second electronic control unit 2 to boost the voltage provided by the non-faulty battery pack to a preset voltage and provide the voltage to at least one of the n first electronic control units 3 includes:

[0106] According to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack, the upper tube and the lower tube of the target bridge arm in the second electronic control unit 2 are controlled to be alternately turned on at a preset frequency, so that the target bridge arm and the target winding in the second electronic control unit 2 form a boost circuit to boost the voltage provided by the non-faulty battery pack to a preset voltage, and provide the preset voltage to at least one of the n first electronic control units 3 through the DC port 211.

[0107] The target bridge arm is at least one bridge arm of the inverter 21 of the second electronic control unit 2 , and the target winding is a winding in the motor 22 of the second electronic control unit 2 that is electrically connected to the target bridge arm.

[0108] Exemplarily, the preset frequency is between 5KHz and 20KHz.

[0109] For example, Figure 2As shown, the inverter 21 includes three bridge arms, namely, a first bridge arm, a second bridge arm and a third bridge arm, wherein the first bridge arm includes an upper tube T1 and a lower tube T4, the second bridge arm includes an upper tube T2 and a lower tube T5, the third bridge arm includes an upper tube T3 and a lower tube T6, and the motor 22 includes an A-phase winding WA, a B-phase winding WB and a C-phase winding WC.

[0110] Among them, the first connection end of the upper tube T1, the first connection end of the upper tube T2 and the first connection end of the upper tube T3 are connected together to form a first bus terminal, the second connection end of the upper tube T1 is electrically connected to the first connection end of the lower tube T4 to form the midpoint of the first bridge arm, the second connection end of the upper tube T2 is electrically connected to the first connection end of the lower tube T5 to form the midpoint of the second bridge arm, the second connection end of the upper tube T3 is electrically connected to the first connection end of the lower tube T6 to form the midpoint of the third bridge arm, the second connection end of the lower tube T4, the second connection end of the lower tube T5 and the second connection end of the lower tube T6 are connected together to form a second bus terminal, the first bus terminal and the second bus terminal constitute the DC port 211, and the midpoint of the first bridge arm, the midpoint of the second bridge arm and the midpoint of the third bridge arm constitute the AC port 212. One end of the A-phase winding WA is electrically connected to the midpoint of the first bridge arm, one end of the B-phase winding WB is electrically connected to the midpoint of the second bridge arm, one end of the C-phase winding WC is electrically connected to the midpoint of the second bridge arm, and the other end of the A-phase winding WA, the other end of the B-phase winding WB, and the other end of the C-phase winding WC are connected together to form a neutral point of the motor 22.

[0111] Exemplarily, in some embodiments, the switch tubes in the inverter 21 (including the upper tube T1 to the lower tube T6) are all metal oxide semiconductor field effect transistors (MOSFET), such as NMOS. Of course, in other embodiments, one or more of various types of switch tubes such as relays, bipolar junction transistors (BJT), and insulated gate bipolar transistors (IGBT) can also be used, and the embodiments of the present application will not list them one by one.

[0112] In the embodiment of the present application, the target bridge arm may be any one, any two or three of the first bridge arm, the second bridge arm and the third bridge arm. For example, in some embodiments, the target bridge arm is the first bridge arm, and the target winding is the A-phase winding WA; in some embodiments, the target bridge arm is the first bridge arm and the second bridge arm, and the target winding is the A-phase winding WA and the B-phase winding WB; in some embodiments, Figure 4 and Figure 5 As shown, the target bridge arms are the first bridge arm, the second bridge arm and the third bridge arm, and the target windings are the A-phase winding WA, the B-phase winding WB and the C-phase winding WC.

[0113] Among them, a cycle corresponding to the preset frequency includes a first time period and a second time period which are performed successively, and the upper tube and the lower tube of the target bridge arm in the second electronic control unit 2 are controlled to be turned on alternately according to the preset frequency, including:

[0114] In the first period, the upper tubes of all target bridge arms are controlled to be turned on, and the lower tubes of all target bridge arms and the upper tubes and lower tubes of all bridge arms other than the target bridge arms are controlled to be turned off; in the second period, the lower tubes of all target bridge arms are controlled to be turned on, and the upper tubes of all target bridge arms and the upper tubes and lower tubes of all bridge arms other than the target bridge arms are controlled to be turned off; or,

[0115] In the first time period, the lower tubes of all target bridge arms are controlled to be turned on, and the upper tubes of all target bridge arms and the upper tubes and lower tubes of bridge arms other than the target bridge arms are controlled to be turned off. In the second time period, the upper tubes of all target bridge arms are controlled to be turned on, and the lower tubes of all target bridge arms and the upper tubes and lower tubes of bridge arms other than the target bridge arms are controlled to be turned off.

[0116] Combine the following Figure 4-5 , the working principle of the second electronic control unit 2 when performing the boost function is introduced:

[0117] Assuming that the first battery group 11 is a faulty battery group and the second battery group 12 is a normal battery group, the first switch K1 is first controlled to be turned on, and the second switch K2 in the first battery group 11 is controlled to be turned off, and the second switch K2 in the second battery group 12 is controlled to be turned on, and then the second electronic control unit 2 is controlled to perform the boost function.

[0118] Specifically, when performing the boost function, such as Figure 4As shown, in the first period of each cycle corresponding to the preset frequency, the lower tubes of all target bridge arms are controlled to be turned on, and the upper tubes of all target bridge arms are controlled to be turned off. At this time, the second battery pack 12 charges the A-phase winding WA through the turned-on lower tube T4, charges the B-phase winding WB through the turned-on lower tube T5, and charges the C-phase winding WC through the turned-on lower tube T6, and the charging current remains basically constant. At the same time, the capacitor C1 supplies power to the n first electric control units 3, and the power supply voltage remains basically constant.

[0119] like Figure 5 As shown, in the second period of each cycle corresponding to the preset frequency, the upper tubes of all target bridge arms are controlled to be turned on, and the lower tubes of all target bridge arms are controlled to be turned off. At this time, since the winding (equivalent to the inductor) has the characteristic that the current cannot change suddenly, the A-phase winding WA is freewheeling through the turned-on upper tube T1, that is, the A-phase winding WA and the second battery pack 12 simultaneously charge the capacitor C1 through the turned-on upper tube T1, and supply power to the n first electric control units 3, and the power supply voltage is basically constant and equal to the voltage of the A-phase winding WA. The sum of the voltage of the A-phase winding WA and the voltage of the second battery pack 12, similarly, the B-phase winding WB is freewheeling through the upper tube T2 that is turned on, that is, the B-phase winding WB and the second battery pack 12 are simultaneously charged by the upper tube T2 that is turned on, and the n first electric control units 3 are powered, and the C-phase winding WC is freewheeling through the upper tube T3 that is turned on, that is, the C-phase winding WC and the second battery pack 12 are simultaneously charged by the upper tube T3 that is turned on, and the n first electric control units 3 are powered. Since in the process of controlling the upper tube and the lower tube of the target bridge arm in the second electric control unit 2 to be alternately turned on at a preset frequency, the voltage across the capacitor C1 is substantially constant and equal to the sum of the voltage of the A-phase winding WA and the voltage of the second battery pack 12 (that is, the preset voltage), which is greater than the voltage of the second battery pack 12, therefore, the second electric control unit 2 can play a role in boosting.

[0120] Among them, when executing the boost function, the boost ratio of the second electronic control unit 2 is related to the duration ratio of the first time period and the second time period in a cycle. Specifically, the relationship between the output voltage Uout and the input voltage Uin of the second electronic control unit 2 is: Uout=Uin / (1-D), wherein D=T1 / (T1+T2), D is the duty cycle, T1 is the duration of the first time period, and T2 is the duration of the second time period.

[0121] In some embodiments, the controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit 2 to be alternately turned on at a preset frequency according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack includes:

[0122] According to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack, a target duty cycle D1 is obtained;

[0123] According to the target duty cycle D1, a first control signal and a second control signal are generated, both of which have a preset frequency; wherein the duty cycle of the first control signal is the target duty cycle D1, and the second control signal is inverted with the first control signal; and,

[0124] According to the fault conditions of the first battery group 11 and the second battery group 12, the first control signal is output to the upper tube of the target bridge arm in the second electronic control unit 2 and the second control signal is output to the lower tube of the target bridge arm in the second electronic control unit 2, or the second control signal is output to the upper tube of the target bridge arm in the second electronic control unit 2 and the first control signal is output to the lower tube of the target bridge arm in the second electronic control unit 2, thereby controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit 2 to be alternately turned on at a preset frequency.

[0125] Exemplarily, both the first control signal and the second control signal are PWM signals.

[0126] In this way, the voltage boost ratio of the second electronic control unit 2 can be adjusted by adjusting the duty cycle of the first control signal, so that the second electronic control unit 2 can output a suitable voltage.

[0127] In some embodiments, the step of obtaining a target duty cycle according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack includes:

[0128] The target duty cycle is calculated according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack according to a preset duty cycle calculation formula; wherein the preset duty cycle calculation formula is D1=Ub / (Ua+Ub), D1 is the target duty cycle, Ua is the rated voltage of the non-faulty battery pack, and Ub is the rated voltage of the faulty battery pack.

[0129] In some embodiments, Figure 4-5 As shown, the first battery pack 11 is a faulty battery pack, and the second battery pack 12 is a non-faulty battery pack. In this case, D1=U1 / (U1+U2), wherein U1 is the rated voltage of the first battery pack 11, and U2 is the rated voltage of the second battery pack 12. In other embodiments, the first battery pack 11 is a non-faulty battery pack, and the second battery pack 12 is a faulty battery pack. In this case, D1=U2 / (U1+U2).

[0130] It is not difficult to understand that the voltage provided by the power battery 1 under normal circumstances is U1+U2. Therefore, setting D1=Ub / (Ua+Ub) allows Uout=Ua / (1-D)=Ua / (1-Ub / (Ua+Ub))=Ua+Ub=U1+U2, that is, the output voltage Uout of the second electronic control unit 2 is consistent with the voltage provided by the power battery 1 under normal circumstances, which can ensure that the motor 22 in the first electronic control unit 3 can perform at its best performance.

[0131] In some embodiments, according to the fault conditions of the first battery group 11 and the second battery group 12, the first control signal is output to the upper tube of the target bridge arm in the second electric control unit 2 and the second control signal is output to the lower tube of the target bridge arm in the second electric control unit 2, or the second control signal is output to the upper tube of the target bridge arm in the second electric control unit 2 and the first control signal is output to the lower tube of the target bridge arm in the second electric control unit 2, so as to control the upper tube and the lower tube of the target bridge arm in the second electric control unit 2 to be alternately turned on at a preset frequency, including:

[0132] When the first battery pack 11 fails, the second control signal is output to the upper tube of the target bridge arm in the second electric control unit 2 and the first control signal is output to the lower tube of the target bridge arm in the second electric control unit 2, so as to control the upper tube and the lower tube of the target bridge arm in the second electric control unit 2 to be alternately turned on at a preset frequency; and

[0133] When a fault occurs in the second battery pack 12, the first control signal is output to the upper tube of the target bridge arm in the second electronic control unit 2 and the second control signal is output to the lower tube of the target bridge arm in the second electronic control unit 2, thereby controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit 2 to be alternately turned on at a preset frequency.

[0134] In some embodiments, Figure 4-5 As shown, when the first battery group 11 fails and the second battery group 12 is not faulty, the second control signal is output to the upper tube (i.e., upper tube T1 to upper tube T3) of the target bridge arm in the second electronic control unit 2 and the first control signal is output to the lower tube (i.e., lower tube T4 to lower tube T6) of the target bridge arm in the second electronic control unit 2.

[0135] In some embodiments, the control method of the drive system further includes:

[0136] Obtaining status information of a single cell; and,

[0137] According to the status information of the single battery cells, it is determined that one of the first battery group 11 and the second battery group 12 is faulty.

[0138] Exemplarily, the drive system may further include a battery management system (BMS), which may be used to obtain status information of a single cell, wherein the status information includes voltage, temperature, current, and the like. In some embodiments, a single cell whose voltage value is not within a preset voltage value threshold range may be identified as a faulty cell, in some embodiments, a single cell whose temperature value is not within a preset temperature value threshold range may be identified as a faulty cell, and in some embodiments, a single cell whose maximum current value is less than a preset current threshold may be identified as a faulty cell. When one of the first battery pack 11 and the second battery pack 12 contains at least one faulty cell, the battery pack is identified as a faulty battery pack.

[0139] like Figure 2 As shown, in some embodiments, the n first electric control units 3 and one of the second electric control units 2 are reused as charging units. The drive system 100 also includes a DC charging port 4, a capacitor C2, a third switch K3 and a fourth switch K4.

[0140] Among them, one end of the third switch K3 is electrically connected to the neutral point of the motor 22 in the charging unit, the other end of the third switch K3 is electrically connected to the positive electrode of the capacitor C2 and the positive electrode of the DC charging port 4, the negative electrode of the capacitor C2 is electrically connected to the negative electrode of the second battery pack 12 and one end of the fourth switch K4, and the other end of the fourth switch K4 is electrically connected to the negative electrode of the DC charging port 4.

[0141] The multi-phase windings of the motor 22 in the charging unit and the inverter 21 form a charging circuit, and the charging circuit is used to boost the DC power received by the DC charging port to charge the power battery 1.

[0142] Please refer again Figure 1 Based on the same inventive concept, the present application also provides a driving system 100 including a power battery 1, n first electronic control units 3, a second electronic control unit 2 and a controller (not shown in the figure). Wherein, n is an integer, n≥1.

[0143] The power battery 1 includes a first battery group 11 and a second battery group 12 , and a negative electrode of the first battery group 11 is electrically connected to a positive electrode of the second battery group 12 .

[0144] Each of the first electric control unit 3 and the second electric control unit 2 includes an inverter 21 and a motor 22. The inverter 21 includes an AC port 212 and a DC port 211. The DC port 211 is electrically connected to the positive electrode of the first battery pack 11 and the negative electrode of the second battery pack 12, and the AC port 212 is electrically connected to the corresponding motor 22. The neutral point of the motor 22 in the second electric control unit 2 is electrically connected to the negative electrode of the first battery pack 11 and the positive electrode of the second battery pack 12.

[0145] The controller is electrically connected to the n first electric control units 3 and the second electric control unit 2, and is used to execute the control method of the drive system described in any of the above embodiments.

[0146] See also Figure 6 Based on the same inventive concept, the present application also provides a vehicle 1000, which includes a vehicle body 200 and a drive system 100 as described in any of the above embodiments. The drive system 100 is disposed in the vehicle body 200.

[0147] The drive system 100 and vehicle 1000 provided in the present application, when one of the first battery pack 11 and the second battery pack 12 fails, controls the second electronic control unit 2 to receive the voltage provided by the non-faulty battery pack, and controls the second electronic control unit 2 to boost the voltage provided by the non-faulty battery pack to a preset voltage, so that at least one of the n first electronic control units 3 can operate normally. In this way, the problem of the vehicle suddenly breaking down and losing power due to the failure of a single battery cell can be avoided, the reliability of the drive system 100 can be improved, and the safety of the vehicle can be improved.

[0148] Based on the same inventive concept, the present application also provides a computer-readable storage medium, which stores executable instructions. When the executable instructions are executed by a processor, the control method of the drive system described in any of the above embodiments is implemented.

[0149] The computer storage medium of the embodiment of the present application can adopt any combination of one or more computer-readable media. Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above. More specific examples (non-exhaustive lists) of computer-readable storage media include: electrical connections with one or more wires, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In this document, computer-readable storage media can be any tangible medium containing or storing programs, which can be used by instruction execution systems, devices or devices or used in combination with them.

[0150] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0151] The program code embodied on the computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0152] Computer program code for performing the operations of the present invention may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as C or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer or may be connected to an external computer (e.g., via the Internet using an Internet service provider) through any type of network, including a local area network (LAN) or a wide area network (WAN).

[0153] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A control method for a drive system, characterized in that: The control method of the drive system comprises: When a battery pack in the first battery pack and the second battery pack fails, the second electronic control unit is controlled to receive a voltage provided by a non-faulty battery pack; wherein the non-faulty battery pack is a battery pack in the first battery pack and the second battery pack that has not failed; controlling the second electronic control unit to boost the voltage provided by the non-faulty battery pack to a preset voltage and provide the voltage to at least one of the n first electronic control units; and Controlling at least one of the first electronic control units to drive a corresponding motor to operate according to a preset voltage; Wherein, the driving system comprises: A power battery, comprising a first battery group and a second battery group, wherein a negative electrode of the first battery group is electrically connected to a positive electrode of the second battery group; n first electronic control units; wherein n is an integer and n≥1; and The second electronic control unit.

2. The control method of the drive system according to claim 1, characterized in that: The controlling the second electric control unit to receive the voltage provided by the non-faulty battery pack comprises: Controlling the first switch to be turned on so that the second electronic control unit receives the voltage provided by the non-faulty battery pack; The second electronic control unit includes a motor and a first switch, a first end of the first switch is electrically connected to the motor in the second electronic control unit, and a second end of the first switch is electrically connected to both the negative electrode of the first battery pack and the positive electrode of the second battery pack.

3. The control method of the drive system according to claim 1, characterized in that: Before controlling the second electric control unit to receive the voltage provided by the non-faulty battery pack, the control method of the drive system further includes: When a battery pack of the first battery pack and the second battery pack fails, controlling the second switch in the non-faulty battery pack to be turned on, and controlling the second switch in the faulty battery pack to be turned off; Wherein, the first battery pack and the second battery pack both include a single battery cell and a second switch, and the single battery cell and the second switch are connected in series.

4. The control method of the drive system according to claim 1, characterized in that: The controlling the second electronic control unit to boost the voltage provided by the non-faulty battery pack to a preset voltage and provide the voltage to at least one of the n first electronic control units includes: According to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack, the upper tube and the lower tube of the target bridge arm in the second electronic control unit are controlled to be turned on alternately at a preset frequency, so that the target bridge arm and the target winding in the second electronic control unit form a boost circuit to boost the voltage provided by the non-faulty battery pack to a preset voltage, and provide the voltage to at least one of the n first electronic control units; Among them, the second electronic control unit includes a motor and an inverter, the inverter includes at least one bridge arm connected in parallel between the positive pole of the first battery group and the negative pole of the second battery group, the bridge arm includes an upper tube, a lower tube and a midpoint, at least one phase winding of the motor is electrically connected to the midpoint of at least one bridge arm in the inverter in a one-to-one correspondence; the target bridge arm is at least one bridge arm of the inverter of the second electronic control unit, and the target winding is a winding in the motor of the second electronic control unit that is electrically connected to the target bridge arm.

5. The control method of the drive system according to claim 4, characterized in that: According to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack, controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency includes: deriving a target duty cycle according to a rated voltage of a faulty battery pack and a rated voltage of a non-faulty battery pack; According to the target duty cycle, generating a first control signal and a second control signal, both of which have a preset frequency; wherein the duty cycle of the first control signal is the target duty cycle, and the second control signal is inverted with the first control signal; and According to the fault conditions of the first battery pack and the second battery pack, the first control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the second control signal is output to the lower tube of the target bridge arm in the second electronic control unit, or the second control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the first control signal is output to the lower tube of the target bridge arm in the second electronic control unit, thereby controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency.

6. The control method of the drive system according to claim 5, characterized in that: The step of obtaining a target duty cycle according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack includes: The target duty cycle is calculated according to the rated voltage of the faulty battery pack and the rated voltage of the non-faulty battery pack according to a preset duty cycle calculation formula; wherein the preset duty cycle calculation formula is D1=Ub / (Ua+Ub), D1 is the target duty cycle, Ua is the rated voltage of the non-faulty battery pack, and Ub is the rated voltage of the faulty battery pack.

7. The control method of the driving system according to claim 6, characterized in that: According to the fault conditions of the first battery pack and the second battery pack, the first control signal is output to the upper tube of the target bridge arm in the second electric control unit and the second control signal is output to the lower tube of the target bridge arm in the second electric control unit, or the second control signal is output to the upper tube of the target bridge arm in the second electric control unit and the first control signal is output to the lower tube of the target bridge arm in the second electric control unit, so as to control the upper tube and the lower tube of the target bridge arm in the second electric control unit to be alternately turned on at a preset frequency, comprising: When the first battery pack fails, the second control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the first control signal is output to the lower tube of the target bridge arm in the second electronic control unit, so as to control the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency; and When a fault occurs in the second battery pack, the first control signal is output to the upper tube of the target bridge arm in the second electronic control unit and the second control signal is output to the lower tube of the target bridge arm in the second electronic control unit, thereby controlling the upper tube and the lower tube of the target bridge arm in the second electronic control unit to be alternately turned on at a preset frequency.

8. The control method of the driving system according to claim 3, characterized in that: The control method of the drive system further includes: Obtaining status information of a single cell; and According to the status information of the single battery cells, it is determined that one of the first battery group and the second battery group fails.

9. A drive system, characterized in that: The drive system comprises: A power battery, the power battery comprising a first battery group and a second battery group, wherein the negative electrode of the first battery group is electrically connected to the positive electrode of the second battery group; n first electronic control units; wherein n is an integer, n≥1; a second electronic control unit; and A controller is electrically connected to the n first electric control units and the second electric control unit, and is used to execute the control method of the drive system according to any one of claims 1 to 8.

10. A vehicle, characterized in that: include: Vehicle body; as well as The drive system as claimed in claim 9; wherein the drive system is arranged in the vehicle body.

Images