Primary-secondary vehicle power supply system and control method

Abstract

The invention relates to the technical field of charging control, and particularly discloses a primary-secondary vehicle power supply system and a control method. The system comprises a double-head charging and discharging gun, a primary vehicle power battery, a secondary vehicle power battery, a primary vehicle whole vehicle controller and a secondary vehicle whole vehicle controller, the double-end charging and discharging gun is used for transmitting a charging inserting gun signal to the whole secondary vehicle controller when being inserted into the primary vehicle charging and discharging port and the secondary vehicle charging and discharging port; the secondary vehicle whole vehicle controller is used for collecting a secondary vehicle electric quantity signal of a secondary vehicle power battery and transmitting the secondary vehicle electric quantity signal to the primary vehicle whole vehicle controller through the double-end charging and discharging gun when receiving a charging gun insertion signal; the mother vehicle whole vehicle controller is used for collecting a mother vehicle electric quantity signal of the mother vehicle power battery and controlling the mother vehicle power battery to be in the charging and discharging state of the child vehicle power battery according to the obtained comparison result of the child vehicle electric quantity signal and the mother vehicle electric quantity signal. The power of the secondary vehicle power battery is supplied to the primary vehicle power battery for use, so that the primary vehicle has larger battery capacity.

Description

Technical Field

[0001] The present invention relates to the technical field of charging control, and in particular to a power supply system and control method for a mother-and-child vehicle. Background Art

[0002] The mother-and-child truck for commercial vehicles adopts a specially designed transportation mode, mainly used for cargo transportation. This type of vehicle saves costs and improves efficiency by putting one vehicle on another. In this mode, one vehicle can load another vehicle without returning empty, thereby reducing the cost of unilateral cargo transportation. At the same time, the mother-and-child truck model can reduce tolls and fuel costs (for fuel vehicles), and can also reduce tire wear and extend tire life, thereby further saving costs.

[0003] At present, most new energy commercial vehicles adopt the rear-mounted or side-mounted battery pack layout. In order to achieve a longer driving range, large-capacity battery packs are often used to achieve the effect of long-distance transportation, or battery replacement is used to improve transportation efficiency. The main limitations of the new energy commercial vehicle mother-carriage transportation mode are difficult to charge, long charging time, small battery pack capacity and short driving range.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The main purpose of the present invention is to provide a power supply system and control method for a mother-and-child vehicle, aiming to solve the technical problem of small battery pack capacity and short cruising range in the mother-and-child vehicle transportation mode in the prior art.

[0006] To achieve the above-mentioned object, the present invention provides a mother-child vehicle power supply system, the mother-child vehicle power supply system comprising: a double-head charging and discharging gun, a mother vehicle power battery, a child vehicle power battery, a mother vehicle whole vehicle controller and a child vehicle whole vehicle controller;

[0007] One end of the double-headed charging and discharging gun is connected to the first end of the power battery of the mother vehicle through the charging and discharging port of the mother vehicle, and the other end of the double-headed charging and discharging gun is connected to the first end of the power battery of the sub-vehicle through the charging and discharging port of the sub-vehicle, and the second end of the power battery of the mother vehicle is connected to the vehicle controller of the mother vehicle, and the second end of the power battery of the sub-vehicle is connected to the vehicle controller of the sub-vehicle;

[0008] The double-head charging and discharging gun is used to transmit the charging gun plug signal to the vehicle controller of the sub-vehicle when it is inserted into the charging and discharging port of the mother vehicle and the charging and discharging port of the sub-vehicle;

[0009] The sub-vehicle whole vehicle controller is used to collect the sub-vehicle power signal of the sub-vehicle power battery, and transmit the sub-vehicle power signal to the mother vehicle whole vehicle controller through the double-head charging and discharging gun when receiving the charging plug signal;

[0010] The mother vehicle controller is used to collect the mother vehicle power signal of the mother vehicle power battery, and control the mother vehicle power battery to the charging and discharging state of the sub-vehicle power battery according to the comparison result between the acquired sub-vehicle power signal and the mother vehicle power signal.

[0011] In one embodiment, the mother-child vehicle power supply system includes: a mother vehicle main positive relay, a mother vehicle main negative relay, a mother vehicle charging positive relay and a mother vehicle charging negative relay;

[0012] The first end of the mother vehicle main positive relay is connected to the positive electrode of the mother vehicle power battery and the first end of the mother vehicle charging positive relay at the same time, the second end of the mother vehicle main positive relay is connected to the mother vehicle total positive power line, the second end of the mother vehicle charging positive relay is connected to the mother vehicle charging and discharging port, the first end of the mother vehicle negative positive relay is connected to the negative electrode of the mother vehicle power battery and the first end of the mother vehicle charging negative relay at the same time, the second end of the mother vehicle main negative relay is connected to the mother vehicle total negative power line, and the second end of the mother vehicle charging negative relay is connected to the mother vehicle charging and discharging port.

[0013] In one embodiment, the parent-child vehicle power supply system further includes: a child vehicle main positive relay, a child vehicle main negative relay, a child vehicle charging positive relay, and a child vehicle charging negative relay;

[0014] The first end of the sub-vehicle main positive relay is connected to the positive electrode of the sub-vehicle power battery and the first end of the sub-vehicle charging positive relay at the same time, the second end of the sub-vehicle main positive relay is connected to the sub-vehicle total positive power line, the second end of the sub-vehicle charging positive relay is connected to the sub-vehicle charging and discharging port, the first end of the sub-vehicle negative positive relay is connected to the negative electrode of the sub-vehicle power battery and the first end of the sub-vehicle charging negative relay at the same time, the second end of the sub-vehicle main negative relay is connected to the sub-vehicle total negative power line, and the second end of the sub-vehicle charging negative relay is connected to the sub-vehicle charging and discharging port.

[0015] In addition, to achieve the above purpose, the present invention also proposes a parent-child vehicle power supply control method, the parent-child vehicle power supply control method is applied to the parent-child vehicle power supply system as described above, the method comprising:

[0016] Obtaining a mother vehicle power signal of a mother vehicle power battery and a sub-vehicle power signal of a sub-vehicle power battery;

[0017] Calculating the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold;

[0018] According to the comparison result of the power difference and the preset power threshold, the charging and discharging state of the power battery of the mother vehicle and the power battery of the child vehicle are controlled.

[0019] In one embodiment, after the step of determining the wearing condition of the headset according to the posture signal when receiving the trigger instruction, the method further includes:

[0020] When the headset is in a wearing state, the power management module is driven to execute a preset action corresponding to the trigger instruction.

[0021] In one embodiment, the step of controlling the charging and discharging state of the power battery of the mother vehicle and the power battery of the child vehicle according to the comparison result of the power difference and the preset power threshold comprises:

[0022] When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

[0023] In one embodiment, the step of controlling the charging and discharging state of the power battery of the mother vehicle and the power battery of the child vehicle according to the comparison result of the power difference and the preset power threshold comprises:

[0024] When the power difference is higher than the preset power threshold, detecting whether the power supply system of the parent-child vehicle is in a parking state;

[0025] If the vehicle is in a non-parking state, comparing the power signal of the mother vehicle with the power signal of the child vehicle;

[0026] According to the comparison result, a power battery with a higher power capacity is selected from the power battery of the mother vehicle and the power battery of the child vehicle for power supply.

[0027] In one embodiment, after the step of selecting a power battery with a higher power from the power battery of the mother vehicle and the power battery of the child vehicle for power supply according to the comparison result, the method further includes:

[0028] Continuously obtaining the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold;

[0029] When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

[0030] In one embodiment, after the step of detecting whether the power supply system of the parent-child vehicle is in a parking state when the power difference is higher than the preset power threshold, the method further includes:

[0031] If the vehicle is in a parking state, the power signal of the mother vehicle and the power signal of the child vehicle are compared;

[0032] According to the comparison result, a power battery with a higher power capacity is selected from the power battery of the mother vehicle and the power battery of the child vehicle to charge the other power battery.

[0033] In one embodiment, after the step of selecting a power battery with a higher power from the power battery of the mother vehicle and the power battery of the child vehicle to charge the other power battery according to the comparison result, the method further includes:

[0034] Continuously obtaining the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold;

[0035] When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

[0036] In one embodiment, the step of obtaining the mother vehicle power signal of the mother vehicle power battery and the sub-vehicle power signal of the sub-vehicle power battery includes:

[0037] Determine whether the voltage platforms of the power battery of the mother vehicle and the power battery of the child vehicle are consistent;

[0038] If they are consistent, determine whether the double-headed charging and discharging gun is connected to the charging and discharging port;

[0039] If inserted, the mother vehicle power signal of the mother vehicle power battery and the sub-vehicle power signal of the sub-vehicle power battery are obtained.

[0040] The technical solution of the present invention proposes a power supply system and control method for a mother-child vehicle. The power supply system for the mother-child vehicle includes: a double-headed charging and discharging gun, a mother vehicle power battery, a child vehicle power battery, a mother vehicle whole vehicle controller and a child vehicle whole vehicle controller; one end of the double-headed charging and discharging gun is connected to the first end of the mother vehicle power battery through the mother vehicle charging and discharging port, the other end of the double-headed charging and discharging gun is connected to the first end of the child vehicle power battery through the child vehicle charging and discharging port, the second end of the mother vehicle power battery is connected to the mother vehicle whole vehicle controller, and the second end of the child vehicle power battery is connected to the child vehicle whole vehicle controller; the double-headed charging and discharging gun is used to be inserted into the mother vehicle charging and discharging port. When the charging and discharging port of the sub-car is connected, the charging gun signal is transmitted to the sub-car whole vehicle controller; the sub-car whole vehicle controller is used to collect the sub-car power signal of the sub-car power battery, and when receiving the charging gun signal, the sub-car power signal is transmitted to the mother vehicle whole vehicle controller through the double-headed charging and discharging gun; the mother vehicle whole vehicle controller is used to collect the mother vehicle power signal of the mother vehicle power battery, and control the mother vehicle power battery to the charging and discharging state of the sub-car power battery according to the comparison result between the obtained sub-car power signal and the mother vehicle power signal. By setting the double-headed charging and discharging gun between the sub-car and the mother vehicle, the power of the sub-car power battery is used for the mother vehicle power battery, so that the mother vehicle has a larger battery capacity, reduces the distance to find the charging pile during transportation and shortens the number of charging times, and improves the cruising range of the new energy commercial vehicle when the mother-child vehicle is transported back and forth. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a structural schematic diagram of a first embodiment of a power supply system for a mother-and-child vehicle proposed by the present invention;

[0042] Figure 2 This is a schematic diagram of the structure of the hardware control in the first embodiment of the power supply system for the mother-child vehicle proposed by the present invention;

[0043] Figure 3 This is a schematic diagram of the architecture of the second embodiment of the power supply system for the mother-child vehicle proposed by the present invention;

[0044] Figure 4 This is a flow chart of the first embodiment of the power supply control method for the parent-child vehicle proposed by the present invention;

[0045] Figure 5 This is a flow chart of the second embodiment of the power supply control method for the parent-child vehicle proposed by the present invention.

[0046] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0047] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0050] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0051] Reference Figure 1 , Figure 1 This is a schematic diagram of the structure of the first embodiment of the power supply system for the mother-child vehicle proposed by the present invention. Figure 1 A first embodiment of a power supply system for a parent-child vehicle of the present invention is provided.

[0052] In this embodiment, the power supply system of the mother-child vehicle includes: a double-head charging and discharging gun 10, a mother vehicle power battery 20, a child vehicle power battery 30, a mother vehicle whole vehicle controller 21 and a child vehicle whole vehicle controller 31; one end of the double-head charging and discharging gun 10 is connected to the first end of the mother vehicle power battery 20 through the mother vehicle charging and discharging port 22, and the other end of the double-head charging and discharging gun 10 is connected to the first end of the child vehicle power battery 30 through the child vehicle charging and discharging port 32, the second end of the mother vehicle power battery 20 is connected to the mother vehicle whole vehicle controller 21, and the second end of the child vehicle power battery 30 is connected to the child vehicle whole vehicle controller 31.

[0053] It should be noted that the double-headed charge and discharge gun 10 can be used to transmit the charging gun signal to the sub-vehicle vehicle controller when inserted into the mother vehicle charging and discharging port 22 and the sub-vehicle charging and discharging port 32; the sub-vehicle vehicle controller 31 can be used to collect the sub-vehicle power signal of the sub-vehicle power battery 30, and when receiving the charging gun signal, transmit the sub-vehicle power signal to the mother vehicle controller 21 through the double-headed charge and discharge gun 10; the mother vehicle controller 21 can be used to collect the mother vehicle power signal of the mother vehicle power battery 20, and control the mother vehicle power battery 20 to be the charging and discharging state of the sub-vehicle power battery 30 according to the comparison result between the acquired sub-vehicle power signal and the mother vehicle power signal.

[0054] It should be understood that the mother-child vehicle can be a transportation mode in which one vehicle is placed on another vehicle. After the two vehicles transport the goods, the mother vehicle is used to load the child vehicle for the return trip when the vehicle is empty. The mother vehicle and the child vehicle in this solution are both new energy commercial vehicles, including a power battery management system (BMS) and a vehicle control unit (VCU).

[0055] Furthermore, the double-head charging and discharging gun 10 can be a device for charging new energy vehicles, which can connect the mother vehicle power battery 20 and the child vehicle power battery 30 to realize the function of mutual charging and discharging between the two vehicle power batteries. The two sides of the double-head charging and discharging gun 10 are connected to the charging and discharging ports of the mother and child vehicles through high-voltage wires. For vehicles charged with a single gun, the physical connection is a high-voltage wire, and for vehicles charged with two guns, two high-voltage wires are used to improve the charging and discharging efficiency. At the same time, the double-head charging and discharging gun 10 is also provided with a CAN line to transmit charging and discharging related signals.

[0056] It should be noted that the charging and discharging ports of each vehicle are connected to their respective power battery BMS through hard wires and CAN lines. The hard wires transmit the electric energy of charging and discharging, and the CAN lines transmit the related signals of charging and discharging. The BMS can identify the charging gun signal and the battery power (State of Charge, SOC) signal and return them to the VCU through the CAN line for high-voltage charging and discharging operation identification and judgment. At the same time, the BMS receives the high-voltage power-on and power-off requests sent by the VCU to control the on and off of the body-related relays.

[0057] It should be understood that when the dual-head charging and discharging gun 10 is connected to the charging and discharging ports of the two vehicles, a charging gun signal will be sent to the VCU of the two vehicles so that the VCU confirms that the charging and discharging gun is successfully connected, and each VCU can obtain the remaining power signal of the BMS, and at the same time, each BMS can transmit the remaining power signal to the BMS and VCU of the other vehicle through the dual-head charging and discharging gun 10. For example: when the sub-vehicle vehicle controller 31 receives the charging gun signal of the dual-head charging and discharging gun 10, it controls the sub-vehicle power battery 30 to transmit the sub-vehicle power signal to the mother vehicle power battery 20 through the dual-head charging and discharging gun 10, and then transmits the sub-vehicle power signal and the mother vehicle power signal to the mother vehicle controller 21 through the CAN line. The mother vehicle controller 21 can control the mother vehicle related relays according to the size of the sub-vehicle power signal and the mother vehicle power signal to control the charge and discharge state of the mother vehicle power battery 20, and transmit the charging control signal to the sub-vehicle vehicle controller 31 to control the sub-vehicle related relays to control the charge and discharge state of the sub-vehicle power battery 30.

[0058] In one possible implementation, when the difference between the power signal of the mother vehicle and the power signal of the child vehicle is lower than a preset threshold value (e.g., 5%), it is determined that the power batteries of the current mother and child vehicles are in a parallel expansion state, that is, the child vehicle power battery 30 and the mother vehicle power battery 20 in the parallel expansion state simultaneously supply power to the mother vehicle, the capacity of the mother vehicle power battery 20 is expanded, and the current total battery capacity is the sum of the capacity of the mother vehicle power battery 20 and the capacity of the child vehicle power battery 30. When the difference between the power signal of the mother vehicle and the power signal of the child vehicle is higher than a preset threshold value (e.g., 5%), it is determined that the vehicle with high power needs to discharge the vehicle with low power, and the vehicle with low power performs charging. When the difference between charging and discharging SOC is lower than the above preset threshold value (e.g., 5%), the parallel expansion state of the power battery can be continued.

[0059] Further, refer to Figure 2 , Figure 2 The schematic diagram of the hardware control structure of the first embodiment of the parent-child vehicle power supply system proposed by the present invention is shown in FIG. The parent-child vehicle power supply system further includes: an IC instrument, a motor control unit (MCU) and an integrated thermal management controller (TMS).

[0060] It should be noted that the instrument IC can receive the charging status and other signals sent by the vehicle controller VCU through CAN for display, so as to display the power battery power in numerical form during the charging and discharging process, and can also prompt the vehicle's available cruising range and other information. The integrated thermal management controller TMS can collect battery status information, MCU motor controller status and other temperature states of components that need heat dissipation or heating through the CAN line during the power battery connection process, and drive electronic fans, water pumps, air conditioners, heating PTCs, solenoid valves and other thermal management related components through hard wires or signal lines to heat or cool the battery during the charging and discharging process.

[0061] In this embodiment, the power supply system of the mother-child vehicle includes: a double-head charging and discharging gun, a mother vehicle power battery, a child vehicle power battery, a mother vehicle whole vehicle controller and a child vehicle whole vehicle controller; one end of the double-head charging and discharging gun is connected to the first end of the mother vehicle power battery through the mother vehicle charging and discharging port, the other end of the double-head charging and discharging gun is connected to the first end of the child vehicle power battery through the child vehicle charging and discharging port, the second end of the mother vehicle power battery is connected to the mother vehicle whole vehicle controller, and the second end of the child vehicle power battery is connected to the child vehicle whole vehicle controller; the double-head charging and discharging gun is used to be inserted into the mother vehicle When the charging and discharging port and the charging and discharging port of the sub-vehicle are connected, the charging gun signal is transmitted to the vehicle controller of the sub-vehicle; the sub-vehicle vehicle controller is used to collect the sub-vehicle power signal of the sub-vehicle power battery, and when receiving the charging gun signal, the sub-vehicle power signal is transmitted to the vehicle controller of the mother vehicle through the double-headed charging and discharging gun; the mother vehicle controller is used to collect the mother vehicle power signal of the mother vehicle power battery, and control the mother vehicle power battery to the charging and discharging state of the sub-vehicle power battery according to the comparison result between the obtained sub-vehicle power signal and the mother vehicle power signal. By setting the double-headed charging and discharging gun between the sub-vehicle and the mother vehicle, the power of the sub-vehicle power battery is used for the mother vehicle power battery, so that the mother vehicle has a larger battery capacity, reduces the distance to find the charging pile during transportation and shortens the number of charging times, and improves the cruising range of the new energy commercial vehicle when the mother-child vehicle is transported back and forth.

[0062] Reference Figure 3 , Figure 3 The schematic diagram of the second embodiment of the power supply system for a parent-child vehicle proposed in the present invention is shown in FIG. Based on the first embodiment of the power supply system for a parent-child vehicle, the second embodiment of the power supply system for a parent-child vehicle proposed in the present invention is shown in FIG.

[0063] In this embodiment, the mother-child vehicle power supply system includes: a mother vehicle main positive relay K1, a mother vehicle main negative relay K2, a mother vehicle charging positive relay K3 and a mother vehicle charging negative relay K4.

[0064] Among them, the first end of the mother vehicle main positive relay K1 is connected to the positive electrode of the mother vehicle power battery 20 and the first end of the mother vehicle charging positive relay K3 at the same time, the second end of the mother vehicle main positive relay K1 is connected to the mother vehicle main positive power line, the second end of the mother vehicle charging positive relay K3 is connected to the mother vehicle charging and discharging port 22, the first end of the mother vehicle negative positive relay K2 is connected to the negative electrode of the mother vehicle power battery 20 and the first end of the mother vehicle charging negative relay K4 at the same time, the second end of the mother vehicle main negative relay K2 is connected to the mother vehicle main negative power line, and the second end of the mother vehicle charging negative relay K4 is connected to the mother vehicle charging and discharging port 22.

[0065] Furthermore, the parent-child vehicle power supply system further includes: a child vehicle main positive relay K5, a child vehicle main negative relay K6, a child vehicle charging positive relay K7 and a child vehicle charging negative relay K8;

[0066] Among them, the first end of the sub-vehicle main positive relay K5 is connected to the positive electrode of the sub-vehicle power battery 30 and the first end of the sub-vehicle charging positive relay K7 at the same time, the second end of the sub-vehicle main positive relay K5 is connected to the sub-vehicle total positive power line, the second end of the sub-vehicle charging positive relay K7 is connected to the sub-vehicle charging and discharging port 32, the first end of the sub-vehicle negative positive relay K6 is connected to the negative electrode of the sub-vehicle power battery 30 and the first end of the sub-vehicle charging negative relay K8 at the same time, the second end of the sub-vehicle main negative relay K6 is connected to the sub-vehicle total negative power line, and the second end of the sub-vehicle charging negative relay K8 is connected to the sub-vehicle charging and discharging port 32.

[0067] It should be noted that the main positive power line and the main negative power line of the above-mentioned mother vehicle and child vehicle are power buses for the power battery to supply power to various high-voltage devices on the vehicle.

[0068] It should be understood that the working modes of the power batteries of the mother vehicle and the child vehicle may include: (1) Parallel expansion mode, in which the mother vehicle power battery 20 and the child vehicle power battery 30 are connected in parallel to supply power, and the charging positive relay, charging negative relay, main positive relay and main negative relay of the mother vehicle and the child vehicle are all closed. (2) Battery charging and discharging mode: the mother vehicle power battery 20 supplies power to the child vehicle power battery 30 or the child vehicle power battery 30 supplies power to the mother vehicle power battery 20, the charging positive relay, charging negative relay and main negative relay of the mother vehicle and the child vehicle are closed, and the main positive relay is disconnected. (3) Mother vehicle single battery power supply mode: only the mother vehicle power battery is used to power the mother vehicle for driving, the charging positive relay and charging negative relay of the mother vehicle and the child vehicle are both disconnected, the mother vehicle main positive relay K1 and the mother vehicle main negative relay K2 are closed, and the child vehicle main positive relay K5 and the child vehicle main negative relay K6 are disconnected. (4) Sub-car single battery power supply mode: Only the sub-car power battery is used to power the mother car. The sub-car main negative relay K6, sub-car charging positive relay K7 and sub-car charging negative relay K8 are closed, the sub-car main positive relay K5 is disconnected, the mother car main positive relay K1, mother car charging positive relay K3 and mother car charging negative relay K4 are closed, and the mother car main negative relay K2 is disconnected.

[0069] In this embodiment, the mother-child vehicle power supply system includes: a mother vehicle main positive relay, a mother vehicle main negative relay, a mother vehicle charging positive relay and a mother vehicle charging negative relay, and the mother-child vehicle power supply system also includes: a sub-vehicle main positive relay, a sub-vehicle main negative relay, a sub-vehicle charging positive relay and a sub-vehicle charging negative relay. The closed state of each relay is controlled by the mother vehicle controller and the sub-vehicle controller, thereby realizing the control of the battery charging and discharging mode, achieving the effect of mutual charging and discharging of the power batteries of the mother vehicle and the sub-vehicle, so that the mother vehicle has a larger battery capacity, reducing the distance to find the charging pile during transportation and shortening the number of charging times.

[0070] In addition, the present invention also proposes a power supply control method for a parent-child vehicle. Figure 4 , Figure 4 This is a flow chart of the first embodiment of the power supply control method for the parent-child vehicle proposed by the present invention. The power supply control method for the parent-child vehicle comprises:

[0071] Step S10: obtaining a mother vehicle power signal of a mother vehicle power battery and a sub-vehicle power signal of a sub-vehicle power battery.

[0072] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication and program running functions, or an electronic device capable of realizing the above functions. For example, the above-mentioned mother-child vehicle power supply system, the mother-child vehicle power supply system is taken as an example to illustrate this embodiment and the following embodiments.

[0073] It should be understood that the mother vehicle power signal can be obtained by the mother vehicle controller directly from the mother vehicle BMS through the CAN line. The sub-vehicle power signal can be obtained by the sub-vehicle power battery transmitting to the mother vehicle BMS through a double-head charging and discharging gun and then transmitting to the mother vehicle controller through the CAN line.

[0074] Step S20: Calculate the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and compare the power difference with a preset power threshold.

[0075] It should be noted that the power difference between the power signal of the mother vehicle and the power signal of the child vehicle can be a positive value (i.e., the power signal of the mother vehicle is higher than the power signal of the child vehicle) or a negative value (i.e., the power signal of the mother vehicle is lower than the power signal of the child vehicle). The preset power threshold can be a pre-set power threshold for determining whether the power battery of the mother vehicle or the power battery of the child vehicle needs to be charged. When the absolute value of the power difference exceeds the preset power threshold (e.g., 5%), it is necessary to control the power battery with a higher power to supply power to the power battery with a lower power.

[0076] Step S30: Controlling the charging and discharging states of the power battery of the mother vehicle and the power battery of the child vehicle according to the comparison result between the power difference and the preset power threshold.

[0077] It should be noted that when the power difference is lower than the preset power threshold (e.g. 5%), the power battery of the mother vehicle and the power battery of the child vehicle can be controlled to supply power in parallel. When the power difference is higher than the preset power threshold (e.g. 5%), the power battery with higher power can be controlled to supply power to the power battery with lower power.

[0078] Furthermore, the step S10 includes:

[0079] Step S101: Determine whether the voltage platforms of the power battery of the mother vehicle and the power battery of the child vehicle are consistent.

[0080] It should be noted that the voltage platform of the power battery is the output voltage level of the power battery of new energy vehicles, and all parts and components of new energy vehicles are parameterized and developed and verified at the corresponding voltage level. For example, there are 400V and 800V voltage levels.

[0081] It should be understood that only when the voltage platforms of the mother vehicle power battery and the child vehicle power battery are consistent can they control each other's charging and discharging. For example, when both are 400V or 800V, the collection of the battery power signals of the mother and child vehicles and the control of the charging and discharging functions can be used normally. When the voltage platforms of the child vehicle and the mother vehicle are inconsistent, each vehicle uses its own power battery for power supply.

[0082] Step S102: If they are consistent, determine whether the double-headed charge and discharge gun is connected to the charge and discharge port.

[0083] It should be noted that, when it is determined that the voltage platforms of the power battery of the mother vehicle and the power battery of the child vehicle are consistent, the acquisition of the battery power signal of the mother vehicle and the control of the charging and discharging functions can be used normally, and the double-head charging and discharging gun can also be normally inserted into the charging and discharging port of the mother vehicle. After the double-head charging and discharging gun is connected to the charging and discharging port, it can send a charging gun signal to the BMS. When the BMS receives the charging gun signal, it determines that the double-head charging and discharging gun is connected.

[0084] Step S103: If inserted, obtaining the mother vehicle power signal of the mother vehicle power battery and the sub-vehicle power signal of the sub-vehicle power battery.

[0085] It should be noted that after the power battery detects that the dual-head charging and discharging gun is connected to the charging and discharging port, the sub-vehicle power battery can transmit the sub-vehicle power signal to the mother vehicle power battery through the CAN line, and then transmit the sub-vehicle power signal and the mother vehicle power signal to the mother vehicle whole vehicle controller. Similarly, the mother vehicle power battery can transmit the mother vehicle power signal to the sub-vehicle power battery through the CAN line, and then transmit the sub-vehicle power signal and the mother vehicle power signal to the sub-vehicle whole vehicle controller.

[0086] In this embodiment, the power signal of the mother vehicle power battery and the power signal of the child vehicle power battery are obtained; the power difference between the mother vehicle power signal and the child vehicle power signal is calculated, and the power difference is compared with a preset power threshold; according to the comparison result of the power difference and the preset power threshold, the charge and discharge state of the mother vehicle power battery and the child vehicle power battery is controlled. By controlling the charge and discharge of the mother vehicle power battery and the child vehicle power battery according to the battery power, the mother vehicle can have a larger capacity battery pack and obtain a longer driving range, avoiding the time-consuming and labor-intensive search for charging piles along the way, shortening the transportation time, and improving the transportation efficiency.

[0087] Reference Figure 5 , Figure 5 This is a flow chart of the second embodiment of the power supply control method for the parent-child vehicle proposed by the present invention. The step S30 includes:

[0088] Step S501: When the power difference is higher than the preset power threshold, detecting whether the power supply system of the parent-child vehicle is in a parking state.

[0089] It should be noted that when the power difference between the power signal of the mother vehicle and the power signal of the child vehicle is higher than the preset power threshold, the charging and discharging functions need to be controlled according to the running status of the vehicle. If the mother vehicle is in driving status at this time, the power battery should supply power for the vehicle operation and will not charge the other power battery.

[0090] Step S502: If the vehicle is in a non-parking state, compare the power signal of the parent vehicle and the power signal of the child vehicle.

[0091] Step S503: According to the comparison result, a power battery with a higher power is selected from the power battery of the mother vehicle and the power battery of the child vehicle for power supply.

[0092] It should be noted that when the mother vehicle is in a non-parking state, the power battery with higher power among the mother vehicle power battery and the sub-vehicle power battery is judged by the positive or negative value of the above-mentioned power difference, that is, when the power difference is positive, the mother vehicle power battery has higher power, and when the power difference is negative, the sub-vehicle power battery has higher power.

[0093] It should be understood that at this time, the mother vehicle uses a single power battery with a higher power capacity to drive and travel, meeting the driving and control needs of the entire vehicle and various electrical appliances.

[0094] Furthermore, after step S503, the method further includes:

[0095] Step S504: continuously obtaining the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold.

[0096] It should be noted that as the power battery with a higher power level continues to supply power, the power level of the power battery will gradually decrease until the power difference of the power battery of the parent-child vehicle is lower than the preset power threshold. Therefore, it is necessary to collect the power difference of the power battery of the parent-child vehicle in real time and compare it with the preset power threshold.

[0097] Step S505: When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

[0098] It should be noted that when the above-mentioned power battery with higher power continues to supply power so that the power difference with the power of another power battery is lower than the preset power threshold (for example, 5%), the battery parallel capacity expansion mode is entered, and the power batteries of the mother and child vehicles are connected in parallel to power the mother vehicle to achieve the purpose of expanding the battery capacity.

[0099] Furthermore, after step S501, the method further includes:

[0100] Step S506: If the vehicle is in a parked state, compare the power signal of the parent vehicle and the power signal of the child vehicle.

[0101] Step S507: According to the comparison result, a power battery with a higher power level is selected from the power battery of the mother vehicle and the power battery of the child vehicle to charge the other power battery.

[0102] It should be noted that when the mother vehicle is in a parked state, the power battery with higher power among the mother vehicle power battery and the sub-vehicle power battery is judged by the positive or negative value of the above-mentioned power difference, that is, when the power difference is positive, the mother vehicle power battery has higher power, and when the power difference is negative, the sub-vehicle power battery has higher power.

[0103] It should be understood that at this time, a power battery with a higher power is selected to charge a power battery with a lower power so that the power of the parent and child vehicle is more balanced.

[0104] Furthermore, after step S507, the method further includes:

[0105] Step S508: continuously obtaining the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold.

[0106] It should be noted that as the power battery with a higher power level continues to charge the power battery with a lower power level, the remaining power of the power battery with a higher power level will gradually decrease until the power difference between the power batteries of the parent and child vehicle is lower than the preset power threshold. Therefore, it is necessary to collect the power difference between the power batteries of the parent and child vehicle in real time and compare it with the preset power threshold.

[0107] Step S509: When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

[0108] It should be noted that when the power battery with higher power continues to supply power so that the power difference with the power of another power battery is lower than a preset power threshold (for example, 5%), the battery parallel expansion mode is entered to achieve the purpose of expanding the battery capacity.

[0109] In this embodiment, when the power difference is higher than the preset power threshold, it is detected whether the power supply system of the mother-car and the child-car is in a parking state; if it is in a non-parking state, the power signal of the mother car and the power signal of the child car are compared; according to the comparison result, the power battery with higher power is selected from the power battery of the mother car and the power battery of the child car for power supply. If it is in a parking state, the power signal of the mother car and the power signal of the child car are compared; according to the comparison result, the power battery with higher power is selected from the power battery of the mother car and the power battery of the child car to charge the other power battery, so that charging can be achieved when parking and electricity can be used when driving, avoiding the time-consuming and labor-intensive search for charging piles along the way, shortening transportation time, and improving transportation efficiency.

[0110] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0111] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A power supply system for a mother-child vehicle, characterized in that: The power supply system of the mother-child vehicle includes: a double-head charging and discharging gun, a mother vehicle power battery, a child vehicle power battery, a mother vehicle whole vehicle controller and a child vehicle whole vehicle controller; One end of the double-headed charging and discharging gun is connected to the first end of the power battery of the mother vehicle through the charging and discharging port of the mother vehicle, and the other end of the double-headed charging and discharging gun is connected to the first end of the power battery of the sub-vehicle through the charging and discharging port of the sub-vehicle, and the second end of the power battery of the mother vehicle is connected to the vehicle controller of the mother vehicle, and the second end of the power battery of the sub-vehicle is connected to the vehicle controller of the sub-vehicle; The double-head charging and discharging gun is used to transmit the charging gun plug signal to the vehicle controller of the sub-vehicle when it is inserted into the charging and discharging port of the mother vehicle and the charging and discharging port of the sub-vehicle; The sub-vehicle whole vehicle controller is used to collect the sub-vehicle power signal of the sub-vehicle power battery, and transmit the sub-vehicle power signal to the mother vehicle whole vehicle controller through the double-head charging and discharging gun when receiving the charging plug signal; The mother vehicle controller is used to collect the mother vehicle power signal of the mother vehicle power battery, and control the mother vehicle power battery to the charging and discharging state of the sub-vehicle power battery according to the comparison result between the acquired sub-vehicle power signal and the mother vehicle power signal.

2. The power supply system for the parent-child vehicle according to claim 1, characterized in that: The mother-child vehicle power supply system comprises: a mother vehicle main positive relay, a mother vehicle main negative relay, a mother vehicle charging positive relay and a mother vehicle charging negative relay; The first end of the mother vehicle main positive relay is connected to the positive electrode of the mother vehicle power battery and the first end of the mother vehicle charging positive relay at the same time, the second end of the mother vehicle main positive relay is connected to the mother vehicle total positive power line, the second end of the mother vehicle charging positive relay is connected to the mother vehicle charging and discharging port, the first end of the mother vehicle negative positive relay is connected to the negative electrode of the mother vehicle power battery and the first end of the mother vehicle charging negative relay at the same time, the second end of the mother vehicle main negative relay is connected to the mother vehicle total negative power line, and the second end of the mother vehicle charging negative relay is connected to the mother vehicle charging and discharging port.

3. The power supply system for the mother-child vehicle according to claim 2, characterized in that: The parent-child vehicle power supply system also includes: a child vehicle main positive relay, a child vehicle main negative relay, a child vehicle charging positive relay and a child vehicle charging negative relay; The first end of the sub-vehicle main positive relay is connected to the positive electrode of the sub-vehicle power battery and the first end of the sub-vehicle charging positive relay at the same time, the second end of the sub-vehicle main positive relay is connected to the sub-vehicle total positive power line, the second end of the sub-vehicle charging positive relay is connected to the sub-vehicle charging and discharging port, the first end of the sub-vehicle negative positive relay is connected to the negative electrode of the sub-vehicle power battery and the first end of the sub-vehicle charging negative relay at the same time, the second end of the sub-vehicle main negative relay is connected to the sub-vehicle total negative power line, and the second end of the sub-vehicle charging negative relay is connected to the sub-vehicle charging and discharging port.

4. A method for controlling power supply of a mother-child vehicle, characterized in that: The parent-child vehicle power supply control method is applied to the parent-child vehicle power supply system according to any one of claims 1 to 3; the method comprises: Obtaining a mother vehicle power signal of a mother vehicle power battery and a sub-vehicle power signal of a sub-vehicle power battery; Calculating the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold; According to the comparison result of the power difference and the preset power threshold, the charging and discharging state of the power battery of the mother vehicle and the power battery of the child vehicle are controlled.

5. The power supply control method for the parent-child vehicle according to claim 4, characterized in that: The step of controlling the charging and discharging states of the power battery of the mother vehicle and the power battery of the child vehicle according to the comparison result of the power difference and the preset power threshold comprises: When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

6. The power supply control method for the parent-child vehicle according to claim 4, characterized in that: The step of controlling the charging and discharging states of the power battery of the mother vehicle and the power battery of the child vehicle according to the comparison result of the power difference and the preset power threshold comprises: When the power difference is higher than the preset power threshold, detecting whether the power supply system of the mother-child vehicle is in a parking state; If the vehicle is in a non-parking state, comparing the power signal of the mother vehicle with the power signal of the child vehicle; According to the comparison result, a power battery with a higher power capacity is selected from the power battery of the mother vehicle and the power battery of the child vehicle for power supply.

7. The power supply control method for the parent-child vehicle according to claim 6, characterized in that: After the step of selecting a power battery with a higher power from the power battery of the mother vehicle and the power battery of the child vehicle for power supply according to the comparison result, the method further includes: Continuously obtaining the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold; When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

8. The power supply control method for the parent-child vehicle according to claim 6, characterized in that: After the step of detecting whether the power supply system of the parent-child vehicle is in a parking state when the power difference is higher than the preset power threshold, the method further includes: If the vehicle is in a parking state, the power signal of the mother vehicle and the power signal of the child vehicle are compared; According to the comparison result, a power battery with a higher power capacity is selected from the power battery of the mother vehicle and the power battery of the child vehicle to charge the other power battery.

9. The power supply control method for the parent-child vehicle according to claim 8, characterized in that: After the step of selecting a power battery with a higher power from the power battery of the mother vehicle and the power battery of the child vehicle to charge the other power battery according to the comparison result, the method further includes: Continuously obtaining the power difference between the power signal of the mother vehicle and the power signal of the child vehicle, and comparing the power difference with a preset power threshold; When the power difference is lower than the preset power threshold, the power battery of the mother vehicle and the power battery of the child vehicle are controlled to supply power in parallel.

10. The power supply control method for the parent-child vehicle according to claim 4, characterized in that: The step of obtaining the mother vehicle power signal of the mother vehicle power battery and the sub-vehicle power signal of the sub-vehicle power battery includes: Determine whether the voltage platforms of the power battery of the mother vehicle and the power battery of the child vehicle are consistent; If they are consistent, determine whether the double-headed charging and discharging gun is connected to the charging and discharging port; If inserted, the mother vehicle power signal of the mother vehicle power battery and the sub-vehicle power signal of the sub-vehicle power battery are obtained.

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