An electric vehicle emergency cruising range energy storage and replacement system and control method thereof

Abstract

The present invention discloses an electric vehicle emergency cruising range energy storage and battery replacement system and a control method thereof. The electric vehicle emergency cruising range energy storage and battery replacement system comprises a SOC monitoring execution module, an electric vehicle power battery, a power battery extension module, an emergency electric energy storage module, a first relay, a second relay and a third relay. The SOC monitoring execution module comprises an ECU and a BMS. The electric vehicle power battery is connected to the power battery extension module, the portable battery replacement component is connected to the power battery extension module, and the braking energy recovery component is connected to the power battery and the emergency electric energy storage module; the ECU is connected to the power battery through the BMS to perform SOC monitoring, and the ECU signal is connected to the emergency electric energy storage module to perform voltage monitoring; the present invention solves the problem of insufficient emergency power and emergency cruising range, and only relying on road rescue after the power is exhausted, and provides specific power management methods such as energy supply and energy storage to improve the user's car experience.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and in particular to an electric vehicle emergency cruising range energy storage and battery replacement system and a control method thereof. Background Art

[0002] With the development of the new energy vehicle industry, the market share of electric vehicles is increasing day by day, and the automobile market will have a greater demand for the range of electric vehicles. The range is an important indicator that affects the performance evaluation of electric vehicles. As a result, in the daily use of electric vehicles, range anxiety, power anxiety, and power outages have become important factors that affect the user's pleasant car experience. However, the focus is usually on the power and range of normal driving, but the driver of a pure electric vehicle will still encounter the problem that after the power of the electric vehicle power battery is exhausted, they can only passively rely on road rescue and cannot go to the nearest charging point independently. Even if some electric vehicles are equipped with a second battery, it is not essentially for emergency use, and only provides a power supply method, lacks energy management and charging and energy storage methods, and the power module for battery replacement is limited by technology, has a large size, is difficult to replace, and cannot be operated by the driver himself. In essence, it still relies heavily on charging stations, and has not solved the problems of insufficient emergency power, insufficient emergency range, and charging and energy management of emergency batteries. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] Based on the above problems, the present invention provides an electric vehicle emergency cruising range energy storage and battery replacement system and a control method thereof, which solve the problem of insufficient emergency power and emergency cruising range, and only relying on road rescue after the power is exhausted. The present invention realizes emergency improvement of power and cruising range in a low-charge state through an emergency power storage module, so that there is enough power to support after the power battery is exhausted, and the vehicle can autonomously go to the nearest charging point, thereby improving the user's car experience, and provides specific power management methods such as energy supply and energy storage for the emergency power storage module.

[0005] (II) Technical solution

[0006] Based on the above technical problems, the present invention provides an electric vehicle emergency cruising range energy storage and battery replacement system, including an SOC monitoring execution module, an electric vehicle power battery, a power battery expansion module, an emergency power storage module, a first relay, a second relay and a third relay, the SOC monitoring execution module includes an ECU and a BMS, the emergency power storage module includes a portable battery replacement component and an energy storage battery, the energy storage battery is installed on the portable battery replacement component, the electric vehicle power battery is connected to the power battery expansion module, the portable battery replacement component is connected to the power battery expansion module through a first relay and a manual switch, the power battery extension module is connected to the necessary power components on the electric vehicle, and is connected to the non-essential power components on the electric vehicle through a third relay, the braking energy recovery component on the electric vehicle is connected to the electric vehicle power battery, and is connected to the portable battery replacement component through a second relay; the ECU is connected to the electric vehicle power battery through the BMS to perform SOC monitoring of the electric vehicle power battery, the ECU is connected to the portable battery replacement component for voltage monitoring of the emergency power storage module, and the ECU is connected to the first relay, the second relay and the third relay respectively.

[0007] Furthermore, the SOC monitoring execution module also includes a display instrument, and the ECU is connected to the display instrument to display the monitored voltage value of the emergency power storage module and the SOC value of the electric vehicle power battery on the display instrument.

[0008] Furthermore, the energy storage battery is a portable quick-plug energy storage battery, the portable battery replacement component is a quick-plug base with positive and negative pole anti-misplug interfaces at the bottom, the emergency power storage module is arranged below the spare tire in the trunk or in a storage box in the cabin, and an anti-collision partition is arranged at the arrangement position, and a buffer filler is placed outside the anti-collision partition.

[0009] Furthermore, the energy storage battery is consistent with the type of power battery of the matching vehicle model, the energy density of the energy storage battery is ≥ the energy density of the power battery of the matching vehicle model, the battery capacity of the energy storage battery is in the range of 1 / 4 to 1 / 3 of the power battery capacity of the matching vehicle model, and the battery volume of the energy storage battery does not exceed 1 / 3 of the volume of the power battery of the matching vehicle model; the depth of the quick-plug base is consistent with the height of the portable quick-plug energy storage battery, and after the portable quick-plug energy storage battery is inserted into the quick-plug base, there is a gap of 2 to 3 cm between the quick-plug base and the inner wall of the quick-plug base.

[0010] Furthermore, the power battery expansion module is specifically a DC line extension harness, which includes three branches: a power battery connection end, a power supply end, and a power battery extension end. The branches all have two electrodes, one positive and one negative, and the same poles are connected. The positive and negative poles of the power battery connection end are connected to the positive and negative poles of the electric vehicle power battery; the positive and negative poles of the power supply end are connected to the positive and negative poles of the power supply circuit of the electrical component; and the positive and negative poles of the power battery extension end are connected to the positive and negative poles of the emergency power storage module.

[0011] Furthermore, the portable battery replacement component of the emergency power storage module is also connected to an inefficient charging system, and the inefficient charging system includes a solar charging system.

[0012] Furthermore, the non-essential power components include entertainment and leisure power components, and the necessary power components include power components, auxiliary driving components, and USB interface power components.

[0013] The present invention also discloses a control method for the electric vehicle emergency cruising range energy storage and battery replacement system, including an emergency capacity expansion power management mode and a battery replacement and capacity expansion mode, wherein the emergency capacity expansion power management mode includes:

[0014] S1, the SOC monitoring execution module obtains the voltage value Vi of the emergency power storage module and the SOC value SOC_i of the electric vehicle power battery in real time through the ECU and BMS;

[0015] S2, determine whether SOC_i<A, if so, proceed to step S3, otherwise proceed to step S5;

[0016] S3, determine whether Vi>Vm, Vm is the minimum discharge voltage of the emergency power storage module, if not, the first relay is adjusted to the disconnected state, the process ends, and the battery replacement and expansion mode is automatically entered; if yes, the first relay is controlled to be adjusted to the closed state, the emergency power storage module and the electric vehicle power battery jointly supply power to the electric vehicle, and at the same time, the third relay is adjusted to the disconnected state, and the power supply of non-essential power components is turned off;

[0017] S4. During the power supply process, determine whether Vi>Vm. If so, continue to supply power. Otherwise, the first relay is adjusted to the disconnected state, the emergency power storage module stops emergency power supply, and automatically enters the power replacement and expansion mode, and ends;

[0018] S5, judging whether Vi≥Vo, where Vo is the maximum charging voltage of the emergency power storage module, if so, then the process ends; if not, then proceeding to step S6;

[0019] S6, determining whether the electric vehicle power battery is in a charging state, if so, proceeding to step S7, and adjusting the third relay to a closed state, turning on the power supply of non-essential power components; otherwise, proceeding to step S9;

[0020] S7, judging whether SOC_i>C, if so, adjusting the first relay to a closed state, and the external charging device also charges the emergency power storage module; if not, re-entering step S7;

[0021] S8, during the charging process, determine whether Vi>Vo, if so, the emergency charging ends and the first relay is adjusted to the disconnected state, if not, the emergency charging continues;

[0022] S9, determine whether SOC_i>B, if not, end; if yes, the second relay is adjusted to a closed state, and the braking energy recovery component charges the electric vehicle power battery and the emergency power storage module simultaneously under the braking recovery condition;

[0023] S10, during the charging process, determine whether Vi>Vo or SOC_i≤B is satisfied. If so, the braking recovery emergency charging is terminated and the second relay is adjusted to the disconnected state. Otherwise, the second relay continues to remain in the closed state.

[0024] Among them, A is the minimum charge state allowable when the electric vehicle power battery is driven alone, B is the minimum charge state when the braking recovery system charges the emergency power storage module in the non-external charging state, and C is the minimum charge state when the external charging equipment charges the emergency power storage module in the external charging state.

[0025] Furthermore, in addition to the automatic entry into the battery replacement and capacity expansion mode, it also includes manually entering the battery replacement and capacity expansion mode. When the electric vehicle power battery or the emergency power storage module is not in a power-deficient state, the manual safety switch on the emergency power storage module is manually closed so that the manual switch is disconnected; the operation of entering the battery replacement and capacity expansion mode is: manually replacing the energy storage battery.

[0026] Furthermore, A=10%, B=65%, and C=85%.

[0027] (III) Beneficial effects

[0028] The above technical solution of the present invention has the following advantages:

[0029] (1) The present invention uses an emergency capacity expansion power management strategy to accurately determine the SOC of the electric vehicle power battery, and uses the charging, storage, and discharge functions of the emergency power storage module to achieve emergency battery capacity expansion and emergency improvement of the driving range under low charge state, effectively alleviating power and mileage anxiety, and solving the problem that the electric vehicle can only rely on road rescue when the power is exhausted. The electric vehicle can autonomously go to the nearest charging point through the emergency power storage module, thereby improving the driver's driving experience;

[0030] (2) The present invention strengthens the management of energy flow. Based on the monitoring signal and the emergency expansion power management strategy, the stored power of the emergency power storage module is replenished in time through idle charging and emergency charging by braking recovery, under the premise of ensuring the charging of the power battery, so as to prepare for emergency charging, so that the emergency power storage module can be used for a longer time and the frequency of battery replacement is reduced. Among them, idle charging stores more energy from the external charging device, and the energy provided by the braking energy recovery component to the power battery becomes less, but the less energy is allocated to the emergency power storage module. This energy allocation enables the driver to autonomously find the nearest charging point in advance and deal with the situation of power battery exhaustion more calmly. Moreover, the emergency charging and control of the charging and discharging circuit avoids the energy waste and battery performance loss caused by continuous charging of the emergency power storage module when it is fully charged.

[0031] (3) The present invention monitors the SOC value of the electric vehicle power battery and the real-time voltage value of the emergency power storage module. The voltage value monitoring method has a significantly lower monitoring cost than using two BMSs to monitor the SOC value of the power battery and the emergency power storage module respectively;

[0032] (4) The present invention also provides a battery replacement and expansion mode when the emergency expansion power management mode cannot solve the problem. The emergency power storage module of the present invention utilizes a small-volume, high-energy-density portable quick-plug energy storage battery, a quick-plug base, and a power battery expansion module to achieve convenient battery replacement and power supply. The operation is simple and the weight is light, so that the driver can replace the battery independently, reducing the difficulty of battery replacement. There is no need to rely on store replacement, which also reduces the cost. It effectively solves the problem of slow charging and difficult charging in urban traffic. It is suitable for various road scenes such as urban roads, suburban roads, and highways, and has the characteristics of idle power storage and convenient battery replacement.

[0033] (5) The present invention has good energy compatibility. The emergency power storage module has a low demand for charging efficiency and can be assisted by low-efficiency charging methods such as power recovery and solar charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the present invention in any way. In the accompanying drawings:

[0035] Figure 1 This is an operating principle diagram of an electric vehicle emergency cruising range energy storage and battery replacement system of the present invention;

[0036] Figure 2 This is a flow chart of the emergency capacity expansion power management control strategy of an electric vehicle emergency range energy storage and battery replacement system of the present invention. DETAILED DESCRIPTION

[0037] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0038] The embodiment of the present invention is an electric vehicle emergency range energy storage and battery replacement system, such as Figure 1 As shown, it includes a SOC (State of Charge) monitoring execution module, an electric vehicle power battery, a power battery expansion module, an emergency power storage module, a first relay, a second relay and a third relay;

[0039] The SOC monitoring execution module includes an ECU (Electronic Control Unit), a BMS (Battery management system) and a display instrument. The ECU is used to receive and determine the signal sent by the BMS in real time, monitor the real-time voltage value of the emergency power storage module, and send control instructions. The BMS is used to monitor the SOC information of the electric vehicle power battery and send it to the ECU in real time. The display instrument is used to display the monitored voltage value of the emergency power storage module and the SOC value of the electric vehicle power battery;

[0040] The emergency electric energy storage module includes a portable battery replacement component and an energy storage battery, and the energy storage battery is a portable quick-plug energy storage battery; the energy storage battery is consistent with the type of the power battery of the matching vehicle model, the energy density of the energy storage battery is ≥ the energy density of the power battery of the matching vehicle model, the battery capacity of the energy storage battery is in the range of 1 / 4 to 1 / 3 of the power battery capacity of the matching vehicle model, and the battery volume of the energy storage battery does not exceed 1 / 3 of the volume of the power battery of the matching vehicle model; the emergency electric energy storage module is arranged below the spare tire in the trunk or in the storage box in the cabin, and an anti-collision partition is arranged at the arrangement position, and a buffer filler is placed outside the anti-collision partition; the portable battery replacement component is a quick-plug base with a positive and negative anti-misplugging interface at the bottom, and the positive and negative poles of the extended end of the power battery are respectively connected to the positive and negative poles of the quick-plug base from the outside of the quick-plug base. The depth of the quick-plug base is consistent with the height of the portable quick-plug energy storage battery. After the portable quick-plug energy storage battery is inserted into the quick-plug base, there is a 2-3 cm gap between the quick-plug base and the inner wall of the quick-plug base, and the portable quick-plug energy storage battery is connected to the power battery extension end circuit of the electric vehicle power battery extension module. The portable quick-plug energy storage battery is installed on the quick-plug base to achieve quick replacement.

[0041] The electric vehicle power battery is connected to the power battery expansion module, the quick-plug base of the emergency power storage module is connected to the power battery expansion module through a manual switch and a first relay, the manual switch is disconnected when the manual safety switch on the emergency power storage module is turned off, the power battery expansion module is connected to the necessary power components on the electric vehicle, and is connected to the non-essential power components on the electric vehicle through the third relay, the brake energy recovery component on the electric vehicle is connected to the electric vehicle power battery, and is connected to the quick-plug base of the emergency power storage module through the second relay; the ECU is connected to the electric vehicle power battery through the BMS for SOC monitoring, the ECU is connected to the quick-plug base of the emergency power storage module for voltage monitoring, the ECU is connected to the first relay, the second relay and the third relay respectively, so as to control the opening and closing of the line where the relay is located, and the ECU is connected to the display instrument to display the monitored voltage value of the emergency power storage module and the SOC value of the electric vehicle power battery on the display instrument. The non-essential power components include entertainment and leisure power components, and the necessary power components include power, auxiliary driving, USB interface and other power components.

[0042] The power battery expansion module is specifically a DC line expansion harness, which includes three branches: a power battery connection end, a power supply end, and a power battery expansion end. Each branch has two electrodes, one positive and one negative, and the same poles are connected. The positive and negative poles of the power battery connection end are connected to the positive and negative poles of the electric vehicle power battery; the positive and negative poles of the power supply end are connected to the positive and negative poles of the power supply circuit of the electrical component; and the positive and negative poles of the power battery expansion end are connected to the positive and negative poles of the emergency power storage module.

[0043] The quick-plug base of the emergency power storage module is also connected to an inefficient charging system, such as a solar charging system, to recharge the emergency power storage device in real time by means of inefficient power conversion, thereby achieving "charging while walking".

[0044] The system includes two modes: emergency capacity expansion power management mode and battery replacement capacity expansion mode. The control method in the emergency capacity expansion power management mode is as follows: Figure 2 As shown, in this embodiment, the constant SOC_i=A=10% is the minimum charge state allowed when the power battery is driven alone; the constant SOC_i=B=65% is the minimum charge state for the braking recovery system to charge the emergency power storage module in the non-external charging state; the constant SOC_i=C=85% is the minimum charge state for the external charging device to charge the emergency power storage module in the external charging state.

[0045] The following steps are involved:

[0046] S1, the SOC monitoring execution module obtains the voltage value Vi of the emergency power storage module and the SOC value SOC_i of the electric vehicle power battery in real time through the ECU and BMS;

[0047] The monitoring cost of the voltage Vi is significantly lower than the monitoring cost of the SOC value through the BMS. Therefore, in this embodiment, the voltage value Vi is monitored on the emergency power storage module, and a decision is made based on Vi and SOC_i.

[0048] S2, determine whether SOC_i < 10%, if so, trigger the emergency expansion control logic and go to step S3, otherwise, go to step S5;

[0049] When SOC_i is less than 10%, the electric vehicle power battery is in a power shortage state and requires emergency power supply from the emergency power storage module. Therefore, the subsequent step S3 determines whether the emergency power storage module can provide emergency power supply.

[0050] S3, emergency expansion control logic: determine whether Vi>Vm, if not, the first relay is adjusted to the disconnected state, the end, and automatically enter the battery replacement expansion mode; if so, the ECU triggers the emergency power supply instruction, controls the first relay from the disconnected state to the closed state, so that the power supply line of the emergency power storage module is closed, and the third relay is changed from the closed state to the disconnected state, shutting down the power supply of non-essential power components. At this time, the emergency power storage module and the electric vehicle power battery jointly supply power to the electric vehicle;

[0051] Vm is the minimum discharge voltage of the emergency power storage module. When Vi≤Vm, the emergency power storage module is also short of power and automatically enters the battery replacement and expansion mode. The energy storage battery in the emergency power storage module needs to be replaced to provide emergency power supply. When Vi>Vm, the emergency power storage module can provide emergency power supply and supply power to the electric vehicle together with the electric vehicle power battery. At this time, the power supply is tight and it is necessary to shut down the power supply of non-essential power components.

[0052] S4: During the power supply process, Vi will be judged to determine whether Vi>Vm. If so, the power supply will continue. If not, that is, when Vi≤Vm, the power of the emergency power storage module is exhausted, triggering the power replacement protection mechanism. The first relay changes from the closed state to the open state, and the emergency power supply cannot be triggered. The state ends and the power replacement expansion mode is automatically entered;

[0053] S5, emergency power reserve charging control logic: determine whether Vi≥Vo, Vo is the maximum charging voltage of the emergency power storage module, and its value is slightly lower than the voltage value of the emergency power storage module under full charge state. If so, the emergency power reserve module has sufficient power, and no form of charging will be performed on the emergency power reserve module, and the process ends; if not, proceed to step S6;

[0054] When Vi≥Vo, the emergency power storage module has sufficient power and does not need to be charged; when Vi<Vo, the emergency power storage module can be charged for emergency power supply.

[0055] S6, determine whether the electric vehicle power battery is in a charging state, if so, trigger the idle charging control logic, enter step S7, and at the same time adjust the third relay to a closed state to start the power supply of non-essential power components; otherwise, trigger the braking recovery emergency charging control logic, and enter step S9;

[0056] S7, idle charging control logic: determine whether SOC_i>85%. If so, the ECU triggers the idle charging instruction, and the first relay is adjusted to a closed state. At this time, the external charging device will charge the electric vehicle power battery and the emergency power storage module at the same time; if not, re-enter step S7;

[0057] S8, during this charging process, Vi will be judged to determine whether Vi>Vo. If so, the emergency charging ends, and the first relay changes from closed to open. If not, the first relay continues to remain in the closed state, and the external charging device will continue to charge the electric vehicle power battery and the emergency power storage module at the same time;

[0058] According to steps S6-S8, when the electric vehicle power battery is being charged, if SOC_i≤85%, only the electric vehicle power battery is charged to satisfy the power of the electric vehicle power battery first, and the emergency power storage module waits for SOC_i>85% to start charging. When SOC_i>85%, the external charging device charges the electric vehicle power battery and the emergency power storage module at the same time until Vi>Vo, and the emergency power storage module does not need to continue charging.

[0059] S9, braking recovery emergency energy charging control logic: determine whether SOC_i>65%, if not, do not trigger the braking recovery emergency energy charging instruction, end; if yes, the ECU triggers the braking recovery emergency energy charging instruction, the second relay is adjusted to the closed state, at this time the braking energy recovery component will charge the electric vehicle power battery and the emergency power storage module at the same time under the braking recovery condition;

[0060] When the electric vehicle power battery is not charging, if SOC_i≤65%, the electric vehicle power battery is insufficient, the electric brake energy recovery component only charges the electric vehicle power battery under the brake recovery condition, and will not trigger the brake recovery emergency charging of the emergency power storage module; if SOC_i>65%, the electric vehicle power battery is sufficient, triggering the brake recovery emergency charging of the emergency power storage module, the brake energy recovery component will charge the electric vehicle power battery and the emergency power storage module at the same time under the brake recovery condition; compared with the traditional charging of the electric vehicle power battery only, the electric vehicle power battery is charged relatively less, but through this power distribution strategy, the insufficient power of the electric vehicle power can be detected earlier, and the missing power can be charged to the emergency power storage module, so that when the electric vehicle power battery is exhausted, it can be powered by the emergency power storage module, and actively seek rescue, rather than passively waiting for road rescue. The brake recovery emergency charging here is aimed at the emergency power storage module. The brake energy recovery component in the electric vehicle will always charge the electric vehicle power battery. Only when the electric vehicle power battery is sufficient, will it charge the emergency power storage module and start the brake recovery emergency charging.

[0061] S10. During this charging process, SOC_i and Vi will be judged at the same time to determine whether Vi>Vo or SOC_i≤65% is satisfied. If so, the braking recovery emergency charging ends and the second relay changes from a closed state to an open state. Otherwise, the second relay continues to remain in a closed state. At this time, the braking energy recovery component will continue to charge the electric vehicle power battery and the emergency power storage module at the same time under the braking recovery condition.

[0062] If Vi>Vo, the emergency power storage module is fully charged and does not need to be charged further, but the electric vehicle power battery continues to be charged until SOC_i≤65%; if SOC_i≤65%, the electric vehicle power battery is insufficient, and the electric braking energy recovery component only meets the charging of the electric vehicle power battery and does not charge the emergency power storage module.

[0063] In summary, the emergency power storage module of the system has an emergency power supply state and a charging state:

[0064] (1) Emergency power supply status: When SOC_i is less than 10%, the electric vehicle power battery is out of power. If Vi≤Vm, the emergency power storage module is also out of power and automatically enters the battery replacement and capacity expansion mode. If Vi>Vm, the emergency power storage module is triggered to supply power to the emergency energy storage module until Vi≤Vm, when the emergency power storage module is exhausted and automatically enters the battery replacement and capacity expansion mode.

[0065] (2) Charging status: When SOC_i ≥ 10%, the electric vehicle power battery is not short of power. If Vi ≥ Vo, the emergency power storage module has sufficient power and does not need to be charged; if Vi < Vo, the emergency power storage module can be charged:

[0066] (2.1) Idle charging state: When the electric vehicle power battery is in the charging state and SOC_i>85%, the idle charging is triggered. If SOC_i>85% is not satisfied, it will be triggered when it is satisfied. The external charging device will charge the electric vehicle power battery and the emergency power storage module at the same time until Vi>Vo, and the charging is terminated. The emergency power storage module does not need to be charged anymore;

[0067] (2.2) Braking recovery emergency charging state: When the electric vehicle power battery is not in a charging state, if SOC_i≤65%, the electric braking energy recovery component only charges the electric vehicle power battery, and the braking recovery emergency charging of the emergency power storage module is not triggered; if SOC_i>65%, the braking recovery emergency charging is triggered, and the braking energy recovery component charges the electric vehicle power battery and the emergency power storage module at the same time until one of Vi>Vo or SOC_i≤65% is met, that is, the emergency power storage module does not need to be charged again, or only charges the electric vehicle power battery, and the braking recovery emergency charging of the emergency power storage module is terminated.

[0068] The operation methods in the battery replacement and capacity expansion mode include automatic entry and manual entry, as follows:

[0069] Automatically enter the battery replacement and capacity expansion mode: When the electric vehicle power battery is in a power-deficient state and cannot drive the vehicle and the voltage of the emergency power storage module is lower than Vm, based on the emergency capacity expansion power management mode control logic, that is, SOC_i<10% and Vi<Vm, the emergency battery power is exhausted and the battery replacement protection mechanism is triggered. The first relay changes from a closed state to an open state to ensure the safe battery replacement work. Power off the vehicle, open the trunk (or front trunk), open the fastening buffer device on the surface of the emergency power storage module, and take out the power-deficient portable fast-plug energy storage battery in the emergency power storage module, and replace it with a spare fully charged portable fast-plug energy storage battery. When replacing, install the portable fast-plug energy storage battery according to the positive and negative polarity error prevention instructions, then close the fastening buffer device, close the trunk, and consider objective factors such as battery damage. Power on the vehicle to check whether the SOC value of the electric vehicle power battery and the voltage value Vi of the emergency power storage module displayed on the display instrument are normal. If the voltage value Vi of the emergency power storage module is lower than Vm, the vehicle cannot be driven. If the voltage value Vi is close to the Vo value, the vehicle can be driven normally. After completing the instrument inspection, the battery replacement and capacity expansion mode operation is completed.

[0070] Manually enter the battery replacement and expansion mode: When the electric vehicle power battery or emergency power storage module is not in a power-deficient state, it is necessary to manually close the manual safety switch on the emergency power storage module, so that the manual switch on the emergency power supply line, that is, the line between the emergency power storage module and the power battery expansion module, is in the disconnected state, and then perform the battery replacement operation. After completing the battery replacement, manually open the safety switch, so that the manual switch of the emergency power supply line is in the closed state, close the trunk, power on the vehicle, and check whether the SOC value of the electric vehicle power battery and the voltage value Vi of the emergency power storage module displayed on the display instrument are normal.

[0071] In summary, the above-mentioned electric vehicle emergency cruising range energy storage and replacement system and control method thereof have the following advantages:

[0072] (1) The present invention uses an emergency capacity expansion power management strategy to accurately determine the SOC of the electric vehicle power battery, and uses the charging, storage, and discharge functions of the emergency power storage module to achieve emergency battery capacity expansion and emergency improvement of the driving range under low charge state, effectively alleviating power and mileage anxiety, and solving the problem that the electric vehicle can only rely on road rescue when the power is exhausted. The electric vehicle can autonomously go to the nearest charging point through the emergency power storage module, thereby improving the driver's driving experience;

[0073] (2) The present invention strengthens the management of energy flow. Based on the monitoring signal and the emergency expansion power management strategy, the stored power of the emergency power storage module is replenished in time through idle charging and emergency charging by braking recovery, under the premise of ensuring the charging of the power battery, so as to prepare for emergency charging, so that the emergency power storage module can be used for a longer time and the frequency of battery replacement is reduced. Among them, idle charging stores more energy from the external charging device, and the energy provided by the braking energy recovery component to the power battery becomes less, but the less energy is allocated to the emergency power storage module. This energy allocation enables the driver to autonomously find the nearest charging point in advance and deal with the situation of power battery exhaustion more calmly. Moreover, the emergency charging and control of the charging and discharging circuit avoids the energy waste and battery performance loss caused by continuous charging of the emergency power storage module when it is fully charged.

[0074] (3) The present invention monitors the SOC value of the electric vehicle power battery and the real-time voltage value of the emergency power storage module. The voltage value monitoring method has a significantly lower monitoring cost than using two BMSs to monitor the SOC value of the power battery and the emergency power storage module respectively;

[0075] (4) The present invention also provides a battery replacement and expansion mode when the emergency expansion power management mode cannot solve the problem. The emergency power storage module of the present invention utilizes a small-volume, high-energy-density portable quick-plug energy storage battery, a quick-plug base, and a power battery expansion module to achieve convenient battery replacement and power supply. The operation is simple and the weight is light, so that the driver can replace the battery independently, reducing the difficulty of battery replacement. There is no need to rely on store replacement, which also reduces the cost. It effectively solves the problem of slow charging and difficult charging in urban traffic. It is suitable for various road scenes such as urban roads, suburban roads, and highways, and has the characteristics of idle power storage and convenient battery replacement.

[0076] (5) The present invention has good energy compatibility. The emergency power storage module has a low demand for charging efficiency and can be assisted by low-efficiency charging methods such as power recovery and solar charging.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations shall fall within the scope defined by the appended claims.

Claims

1. An electric vehicle emergency range energy storage and replacement system, characterized in that: It includes an SOC monitoring execution module, an electric vehicle power battery, a power battery extension module, an emergency power storage module, a first relay, a second relay and a third relay. The SOC monitoring execution module includes an ECU and a BMS. The emergency power storage module includes a portable battery replacement component and an energy storage battery. The energy storage battery is installed on the portable battery replacement component. The electric vehicle power battery is connected to the power battery extension module. The portable battery replacement component is connected to the power battery extension module through a first relay and a manual switch. The power battery extension module is connected to necessary power components on the electric vehicle and is connected to non-essential power components on the electric vehicle through a third relay. The braking energy recovery component on the electric vehicle is connected to the electric vehicle power battery and is connected to the portable battery replacement component through a second relay. The ECU is connected to the electric vehicle power battery through the BMS to monitor the SOC of the electric vehicle power battery. The ECU is connected to the portable battery replacement component for voltage monitoring of the emergency power storage module. The ECU is connected to the first relay, the second relay and the third relay respectively. The energy storage battery is a portable quick-plug energy storage battery, the portable battery replacement component is a quick-plug base with positive and negative poles anti-misplug interfaces at the bottom, the emergency power storage module is arranged below the spare tire in the trunk or in the storage box in the cabin, and an anti-collision partition is arranged at the arrangement position, and a buffer filler is placed outside the anti-collision partition; The power battery expansion module is specifically a DC line expansion harness, which includes three branches: a power battery connection end, a power supply end, and a power battery expansion end. Each branch has two electrodes, one positive and one negative, and the same poles are connected. The positive and negative poles of the power battery connection end are connected to the positive and negative poles of the electric vehicle power battery; the positive and negative poles of the power supply end are connected to the positive and negative poles of the power supply circuit of the electrical component; and the positive and negative poles of the power battery expansion end are connected to the positive and negative poles of the emergency power storage module.

2. The electric vehicle emergency cruising range energy storage and replacement system according to claim 1 is characterized in that: The SOC monitoring execution module also includes a display instrument, and the ECU is connected to the display instrument to display the monitored voltage value of the emergency power storage module and the SOC value of the electric vehicle power battery on the display instrument.

3. The electric vehicle emergency cruising range energy storage and replacement system according to claim 1 is characterized in that: The energy storage battery is consistent with the type of power battery of the matching vehicle model, the energy density of the energy storage battery is ≥ the energy density of the power battery of the matching vehicle model, the battery capacity of the energy storage battery is in the range of 1 / 4 to 1 / 3 of the power battery capacity of the matching vehicle model, and the battery volume of the energy storage battery does not exceed 1 / 3 of the volume of the power battery of the matching vehicle model; the depth of the quick-plug base is consistent with the height of the portable quick-plug energy storage battery, and after the portable quick-plug energy storage battery is inserted into the quick-plug base, there is a gap of 2 to 3 cm between the quick-plug base and the inner wall of the quick-plug base.

4. The electric vehicle emergency cruising range energy storage and replacement system according to claim 1 is characterized in that: The portable battery replacement component of the emergency power storage module is also connected to an inefficient charging system, which includes a solar charging system.

5. The electric vehicle emergency cruising range energy storage and replacement system according to claim 1 is characterized in that: The non-essential power components include entertainment and leisure power components, and the necessary power components include power components, auxiliary driving components, and USB interface power components.

6. A control method for an electric vehicle emergency cruising range energy storage and battery replacement system according to any one of claims 1 to 5, characterized in that: It includes an emergency capacity expansion power management mode and a battery replacement capacity expansion mode. The emergency capacity expansion power management mode includes: S1, the SOC monitoring execution module obtains the voltage value Vi of the emergency power storage module and the SOC value SOC_i of the electric vehicle power battery in real time through the ECU and BMS; S2, determine whether SOC_i<A, if so, proceed to step S3, otherwise proceed to step S5; S3, determine whether Vi>Vm, Vm is the minimum discharge voltage of the emergency power storage module, if not, the first relay is adjusted to the disconnected state, the process ends, and the battery replacement and expansion mode is automatically entered; if yes, the first relay is controlled to be adjusted to the closed state, the emergency power storage module and the electric vehicle power battery jointly supply power to the electric vehicle, and at the same time, the third relay is adjusted to the disconnected state, and the power supply of non-essential power components is turned off; S4. During the power supply process, determine whether Vi>Vm. If so, continue to supply power. Otherwise, the first relay is adjusted to the disconnected state, the emergency power storage module stops emergency power supply, and automatically enters the power replacement and expansion mode, and ends; S5, judging whether Vi≥Vo, where Vo is the maximum charging voltage of the emergency power storage module, if so, then ending; if not, then proceeding to step S6; S6, determining whether the electric vehicle power battery is in a charging state, if so, proceeding to step S7, and adjusting the third relay to a closed state, turning on the power supply of non-essential power components; otherwise, proceeding to step S9; S7, judging whether SOC_i>C, if so, adjusting the first relay to a closed state, and the external charging device also charges the emergency power storage module; if not, re-entering step S7; S8. During the charging process, determine whether Vi>Vo. If so, emergency charging ends and the first relay is adjusted to the disconnected state. If not, emergency charging continues. S9, determine whether SOC_i>B, if not, end; if yes, the second relay is adjusted to a closed state, and the braking energy recovery component charges the electric vehicle power battery and the emergency power storage module simultaneously under the braking recovery condition; S10. During the charging process, determine whether Vi>Vo or SOC_i≤B is satisfied. If so, the braking recovery emergency charging is terminated and the second relay is adjusted to the disconnected state. Otherwise, the second relay continues to remain in the closed state. A is the minimum charge state allowed when the electric vehicle power battery is driven alone, B is the minimum charge state of the braking recovery system to charge the emergency power storage module in the non-external charging state, and C is the minimum charge state of the external charging device to charge the emergency power storage module in the external charging state.

7. The control method of the electric vehicle emergency cruising range energy storage and battery replacement system according to claim 6 is characterized in that: In addition to the automatic entry into the battery replacement and capacity expansion mode, it also includes manually entering the battery replacement and capacity expansion mode. When the electric vehicle power battery or the emergency power storage module is not in a power-deficient state, the manual safety switch on the emergency power storage module is manually closed to disconnect the manual switch; the operation of entering the battery replacement and capacity expansion mode is: manually replacing the energy storage battery.

8. The control method of the electric vehicle emergency cruising range energy storage and battery replacement system according to claim 6 is characterized in that: A=10%, B=65%, C=85%.

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