Vehicle, energy conversion device and discharge method thereof

Abstract

The present invention provides a vehicle, an energy conversion device and a discharge method thereof. A first inductor, a second inductor and a first bidirectional H-bridge are provided to form different charge and discharge circuits with a vehicle to be charged. When it is detected that the voltage of a battery module is not higher than the voltage of the vehicle to be charged, the first inductor is used to boost the voltage of a voltage module before charging the voltage of the vehicle to be charged. When it is detected that the voltage of the battery module is higher than the voltage of the vehicle to be charged, the battery module is charged by the second inductor and then the vehicle to be charged is charged by the second inductor. This ensures that the vehicle to be charged can be charged regardless of the voltage of the battery module. The device has strong compatibility and adaptability, does not need to add an external boost or buck circuit, reduces the cost of the external circuit, and realizes charging and discharging between vehicles of different voltage platforms. At the same time, high-power charging can be achieved without an external high-voltage inverter or control box on a cable.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and in particular to a vehicle, an energy conversion device and a discharge method thereof. Background Art

[0002] With the strong support of national policies, new energy vehicles are becoming more and more popular in China. China's new energy vehicle industry has entered a new stage of large-scale development and a period of rapid growth driven by policies and markets. The cruising range and charging convenience of new energy vehicles are extremely important factors for people to consider buying or leasing new energy vehicles. On the one hand, due to the limitations of battery technology development, the cruising range of new energy vehicles is severely restricted; on the other hand, the supporting charging infrastructure is not well built. Although domestic charging piles are constantly improving and developing, the ratio of new energy vehicles to charging piles has only reached 5:1, and it is impossible to ensure that new energy vehicles can find charging facilities in time when the battery is exhausted. Therefore, V2V (Vehicle-to-Vehicle communication) technology came into being under special circumstances. V2V technology is an intelligent network connection technology. Its principle is to use the transmission unit carried by each vehicle to send signals through a high-speed wireless network. This information includes the vehicle's speed, direction, geographical location, route, etc. at the time, to achieve communication between vehicles. However, at this stage, V2V charging technology is limited by new energy vehicle equipment and cannot be charged at high power, resulting in low charging efficiency. In addition, adding a buck-boost circuit or a control box alone results in excessively high costs. Summary of the invention

[0003] The object of the present invention is to provide a vehicle, an energy conversion device and a discharge method thereof, so as to solve the problems in the prior art that the vehicle-to-vehicle charging technology cannot achieve high-power charging resulting in low charging efficiency and the cost is too high by adding a buck-boost circuit or a control box alone.

[0004] The present invention is implemented in this way. In a first aspect, the present invention provides an energy conversion device, characterized in that it includes:

[0005] A first inductor, a first end of which is connected to a first output end of the battery module;

[0006] a second inductor, a first end of which is connected to the first end of the first inductor;

[0007] A second switch connected between the first end of the second inductor and the first end of the charge and discharge port;

[0008] A first bidirectional H-bridge, one end of which is connected to the second output end of the battery module and the second end of the charge and discharge port, and includes a first bridge arm and a second bridge arm connected in parallel, the second end of the first inductor is connected to the first bridge arm, and the second end of the second inductor is connected to the second bridge arm;

[0009] A third switch is connected between the first end of the first inductor and the first end of the charge and discharge port.

[0010] A second aspect of the present invention provides a discharging method for an energy conversion device. Based on the energy conversion device described in the first aspect, when the charging and discharging port of the energy conversion device is connected to a vehicle to be charged, the discharging method comprises:

[0011] Acquiring the voltage of the battery module and the voltage of the vehicle to be charged, and selecting a discharge mode according to the voltage of the battery module and the voltage of the vehicle to be charged, wherein the discharge mode includes boost discharge, buck discharge and isobaric discharge;

[0012] The second switch, the third switch, the first bridge arm and the second bridge arm are controlled to enable the battery module to output direct current, and to enable the battery module to discharge the vehicle to be charged according to the selected discharge mode.

[0013] The third aspect of the present invention provides a vehicle, which also includes the energy conversion device, battery module and charge and discharge port described in the first aspect, one end of the battery module and one end of the energy conversion device are connected to one end of the charge and discharge port, and the other end of the battery module and the other end of the energy conversion device are connected to the other end of the charge and discharge port.

[0014] The present invention provides a vehicle, an energy conversion device and a discharge method thereof. A first inductor, a second inductor and a first bidirectional H-bridge are provided to form different charge and discharge circuits with a vehicle to be charged. When it is detected that the voltage of a battery module is not higher than the voltage of the vehicle to be charged, the first inductor is used to boost the voltage of a voltage module before charging the voltage of the vehicle to be charged. When it is detected that the voltage of the battery module is higher than the voltage of the vehicle to be charged, the battery module is charged by the second inductor and then the vehicle to be charged is charged by the second inductor. This ensures that the vehicle to be charged can be charged regardless of the voltage of the battery module. The device has strong compatibility and adaptability, does not require an additional external boost or buck circuit, reduces the cost of an external circuit, and realizes charging and discharging between vehicles of different voltage platforms. At the same time, high-power charging can be achieved without an external high-voltage inverter or control box on a cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0016] Figure 1 is a structural schematic diagram of an energy conversion device provided in Embodiment 1 of the present invention;

[0017] Figure 2 is another structural schematic diagram of an energy conversion device provided in Embodiment 1 of the present invention;

[0018] Figure 3 is another structural schematic diagram of an energy conversion device provided in Embodiment 1 of the present invention;

[0019] Figure 4 is a circuit diagram of an energy conversion device provided in Embodiment 1 of the present invention;

[0020] Figure 5 is a flow chart of a control method for an energy conversion device provided in Embodiment 2 of the present invention;

[0021] Figure 6 This is a circuit diagram of an energy conversion device connected to a vehicle to be charged provided by Embodiment 2 of the present invention;

[0022] Figure 7 is a current path diagram of a connection between an energy conversion device and a vehicle to be charged provided by the second embodiment of the present invention;

[0023] Figure 8 is another current path diagram of an energy conversion device connected to a vehicle to be charged provided by the second embodiment of the present invention;

[0024] Fig. 9 This is another current path diagram of an energy conversion device connected to a vehicle to be charged provided in the second embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] In order to illustrate the technical solution of the present invention, specific embodiments are provided below for illustration.

[0027] Embodiment 1 of the present invention provides an energy conversion device 10, such as Figure 1As shown, including:

[0028] A first inductor 11, a first end of which is connected to a first output end of the battery module 20 and a first end of the charge and discharge port 30;

[0029] A first switch 14, a first end of which is connected to a first output end of the battery module 20;

[0030] A second inductor 12, a first end of which is connected to a second end of the first switch 14;

[0031] A second switch 15 connected between a first end of the second inductor 12 and a first end of the charge / discharge port 30;

[0032] A first bidirectional H-bridge 13, one end of which is connected to the second output end of the battery module 20 and the second end of the charge and discharge port 30, and includes a first bridge arm 131 and a second bridge arm 132 connected in parallel, the second end of the first inductor 11 is connected to the first bridge arm 131, and the second end of the second inductor 12 is connected to the second bridge arm 132;

[0033] The third switch 16 is connected between the first end of the first inductor 11 and the first end of the charge / discharge port 30 .

[0034] Among them, the battery module 20 is used to provide power to the vehicle; the charging and discharging port 30 is used for external power supply equipment to charge the battery module 20 through the charging and discharging port 30, or the battery module 20 discharges to external power equipment (such as a vehicle) through the charging and discharging port 30; the first inductor 11 is used to store and release electric energy. When the first inductor 11 stores electric energy and discharges together with the battery module 20, boost discharge can be achieved; the second inductor 12 is used to store and release electric energy. When the second inductor 12 discharges alone, buck discharge can be achieved; the first bidirectional H bridge 13 includes a first bridge arm and a second bridge arm, and each phase bridge arm includes two power switches. The power switch can be a transistor, IGBT, MOS tube or other device type. The power switch can achieve bidirectional conduction, and the control end of the power switch is connected to the control end of each power switch. The second switch 15 is connected between the second inductor 12 and the charging and discharging port 30, and can control the second inductor 12 to output or stop outputting energy. The third switch 16 is connected between the battery module 20 and the charge and discharge port 30, and is used to control the battery module 20 to discharge or charge the battery module 20. The second switch is used to control the output energy of the second inductor 12, and the third switch is used to control the battery module 20 to output or stop outputting energy, thereby realizing precise control of the energy conversion device 10. By controlling the second switch 15, the third switch 16 and the four power switches, the battery module 20, the first inductor 11, the second inductor 12, the first bridge arm 131, the second bridge arm and the external electrical equipment form different charging and discharging circuits, thereby performing boost, equal pressure and step-down discharge on the external electrical equipment; the control module may include a vehicle controller, a control circuit of a motor controller and a BMS battery manager circuit, which are connected through a CAN line, and different modules in the control module control the conduction and shutoff of the power switch in the first bidirectional H bridge 13 according to the acquired external electrical equipment information to realize the conduction of different current loops.

[0035] As an implementation method, Figure 2 As shown, the energy conversion device 10 includes a control module 50, which is connected to the battery module 20, the control end of the first bridge arm 131, the control end of the second bridge arm 132, the control end of the first switch 14, the control end of the second switch 15, the control end of the third switch 16, and the control end of the fourth switch 17. When the charging and discharging port 30 is connected to the vehicle to be charged, the control module 50 is used to:

[0036] Obtaining the voltage of the battery module 20 and the voltage of the vehicle to be charged, and selecting a discharge mode according to the voltage of the battery module 20 and the voltage of the vehicle to be charged, wherein the discharge mode includes boost discharge, buck discharge and isobaric discharge;

[0037] The second switch 15 , the third switch 16 , the first bridge arm 131 and the second bridge arm 132 are controlled to enable the battery module 20 to output direct current, and to enable the battery module 20 to discharge the vehicle to be charged according to the selected discharge mode.

[0038] Among them, when the control module 50 detects that the vehicle to be charged is connected to the charging and discharging port 30, the control module compares the voltage of the battery module 20 and the voltage of the vehicle to be charged, and selects different discharge methods to discharge the vehicle to be charged according to the comparison result. When the voltage of the battery module 20 is not higher than the voltage of the vehicle to be charged, a DC boost discharge method can be used to discharge the vehicle to be charged. Since the first inductor 11 can store electrical energy, the power switch in the first bridge arm 131 and the second bridge arm 132 can be controlled to be turned on, and the first inductor 11 can be charged through the battery module 20, and then the battery module 20 and the first inductor 11 are discharged to the vehicle to be charged. During the discharge process, since the first inductor 11 also outputs electrical energy, boost discharge is achieved. By controlling the first bridge arm 131 and the second bridge arm 132, the charging process and the discharging process are alternately performed to achieve boost discharge of the vehicle to be charged. When the control module detects that the voltage of the battery module 20 is higher than the voltage of the vehicle to be charged, a DC step-down discharge method can be used to discharge the vehicle to be charged. Since the second inductor 12 can store electrical energy, the power switches in the first bridge arm 131 and the second bridge arm can be turned on to charge the second inductor 12 through the battery module 20, and then discharge the second inductor 12 to the vehicle to be charged. During the discharge process, since only the second inductor 12 also outputs electrical energy, step-down discharge is achieved. The charging process and the discharging process are alternately performed by controlling the first bridge arm 131 and the second bridge arm 132 to achieve step-down discharge of the vehicle to be charged.

[0039] In the first embodiment of the present invention, a first inductor 11, a second inductor 12, a second switch 15, a third switch 16, and a first bidirectional H-bridge 13 are provided to form different charging and discharging circuits with the vehicle to be charged. When it is detected that the voltage of the battery module 20 is not higher than the voltage of the vehicle to be charged, the first inductor 11 is used to boost the voltage of the voltage module and then charge the voltage of the vehicle to be charged. When it is detected that the voltage of the battery module 20 is higher than the voltage of the vehicle to be charged, the battery module 20 is charged by the second inductor 12 and then the vehicle to be charged is charged by the second inductor 12. This realizes that the vehicle to be charged can be charged regardless of the voltage of the battery module 20, and the compatibility and adaptability are strong. At the same time, there is no need to add an external boost or buck circuit, which reduces the cost of the external circuit, and realizes charging and discharging between vehicles of different voltage platforms. At the same time, high-power charging can be achieved without an external high-voltage inverter or control box on the cable.

[0040] Further, as an implementation mode, the first bridge arm 131 includes a first power switch and a second power switch connected in series, and the second end of the first inductor L1 is connected to the second end of the first power switch and the first end of the second power switch;

[0041] The second bridge arm 132 includes a third power switch and a fourth power switch connected in series, and the second end of the second inductor L2 is connected to the second end of the third power switch and the first end of the fourth power switch;

[0042] The first end of the first power switch and the first end of the third power switch are connected together to form the first bus terminal of the first bidirectional H-bridge 13; the second end of the second power switch and the second end of the fourth power switch are connected together to form the second bus terminal of the first bidirectional H-bridge, and the second bus terminal is connected to the second output terminal of the battery module 20 and the second end of the charge and discharge port 30.

[0043] As an implementation mode, when the control module 50 performs boost discharge, the first switch 14 and the third switch 16 are in the off state, the second switch 15 and the fourth switch 17 are in the on state, the battery module 20, the first inductor 11, the second power switch, and the vehicle to be charged form a first energy storage circuit, and the battery module 20, the first inductor 11, the second power switch, the third power switch, the second inductor 12, the second switch 15, the vehicle to be charged, and the fourth switch 17 form a first discharge circuit;

[0044] The control module controls the bridge arms of the first power switch, the third power switch and the fourth power switch to be in the off state, and controls the bridge arm of the second power switch to be alternately turned on and off, so that the first energy storage circuit and the first discharge circuit work alternately.

[0045] As an implementation mode, when the control module 50 performs step-down discharge, the first switch 14 and the third switch 16 are in the disconnected state, the second switch 15 and the fourth switch 17 are in the on state, the battery module 20, the first inductor 11, the second power switch, the third power switch, the second inductor 12, the second switch 15, the vehicle to be charged, and the fourth switch 17 form a second energy storage circuit, and the second inductor 12, the second switch 15, the vehicle to be charged, the fourth switch 17, and the fourth power switch form a second discharge circuit;

[0046] The control module 50 controls the bridge arms of the first power switch, the second power switch and the third power switch to be in the off state, and controls the bridge arm of the fourth power switch to be alternately turned on and off, so that the second energy storage circuit and the second discharge circuit work alternately.

[0047] Among them, when the energy conversion device 10 performs boost discharge, the control module 50 controls the first switch 14 and the third switch 16 to be in the off state, the second switch 15 and the fourth switch 17 to be in the on state, controls the bridge arms of the first power switch and the fourth power switch to be turned off, controls the bridge arm of the third power switch to be turned on, and when the bridge arm of the second power switch is controlled to be turned on, the battery module 20, the first inductor 11, the second power switch, and the vehicle to be charged form a first energy storage circuit, and the battery module 20 stores energy for the first inductor 11. When the bridge arm of the second power switch is controlled to be turned off, the battery module 20, the first inductor 11, the second power switch, the third power switch, the second inductor 12, the second switch 15, the vehicle to be charged, and the fourth switch 17 form a first discharge circuit, and the battery module 20 and the first inductor 11 discharge the vehicle to be charged. The second power switch is turned on and off by the PWM signal to realize the energy conversion device 10 to perform boost discharge on the vehicle to be charged. When the energy conversion device 10 performs step-down discharge, the control module controls the third switch 16 to be in the off state and the second switch 15 to be in the on state, controls the first power switch, the second power switch, and the fourth power switch to be turned off, and when the third power switch is controlled to be turned on, the battery module 20, the first inductor 11, the second power switch, the third power switch, the second inductor 12, the second switch 15, and the vehicle to be charged form a second energy storage circuit, and the battery module 20 stores energy in the second inductor 12. When the third power switch is controlled to be turned off, the second inductor 12, the second switch 15, the vehicle to be charged, and the fourth power switch form a second discharge circuit, and the fourth power switch is controlled to be turned on and off by the PWM signal, so that the energy conversion device 10 performs step-down discharge on the vehicle to be charged.

[0048] As an implementation mode, when the control module 50 performs isobaric discharge, the third switch 16 is in an on state, the second switch 15 is in an off state, and the battery module 20, the third switch 16, and the vehicle to be charged form a third discharge circuit.

[0049] When the energy conversion device performs isobaric discharge on the vehicle to be charged, the two ends of the batteries of the two vehicles are directly connected, and the battery module 20 directly charges the battery in the vehicle to be charged.

[0050] Further, as an implementation mode, the energy conversion device 10 further includes:

[0051] The first capacitor is connected between the first bus terminal and the second bus terminal.

[0052] The first bidirectional H-bridge 13 is connected to the motor controller, and the motor controller is connected to the motor;

[0053] When the energy conversion device is in a driving state, the battery module 20, the first inductor 11, the second inductor 12, the first bidirectional H-bridge 13, the first capacitor, the motor controller and the motor serve as part of the driving circuit;

[0054] When the energy conversion device is in a discharging state, the battery module 20, the first inductor 11, the second inductor 12, the first bidirectional H-bridge 13, the second switch 15, the third switch 16, and the discharge circuit of the vehicle to be charged;

[0055] The first inductor 11, the second inductor 12, and the first bidirectional H-bridge 13 are reused in the driving circuit and the discharging circuit.

[0056] Among them, the motor controller is a three-phase inverter, and the two ends of the first capacitor are connected to the three-phase inverter for storing electric energy and then driving the motor through the three-phase inverter. The three-phase inverter includes a first power switch unit, a second power switch unit, a third power switch unit, a fourth power switch unit, a fifth power switch unit and a sixth power switch unit. The control end of each power switch unit is connected to the control module, and the input ends of the first power switch unit, the third power switch unit and the fifth power switch unit are connected together to form the first end of the three-phase inverter. The output ends of the second power switch unit, the fourth power switch unit and the sixth power switch unit are connected together to form the second end of the three-phase inverter. The first phase coil of the three-phase AC motor is connected to the output end of the first power switch unit and the input end of the fourth power switch unit, the second phase coil of the three-phase AC motor is connected to the output end of the third power switch unit and the input end of the sixth power switch unit, and the third phase coil of the three-phase AC motor is connected to the output end of the fifth power switch unit and the input end of the second power switch unit.

[0057] In this embodiment, a first capacitor, a three-phase inverter and a three-phase AC motor are connected in sequence at both ends of the first bidirectional H-bridge 13. By reusing the first inductor 11, the second inductor 12 and the first bidirectional H-bridge 13, the battery module 20 drives the three-phase AC motor through the three-phase inverter, which can be used for charging and discharging, and can output power to drive the vehicle.

[0058] Further, as an implementation method, Figure 3 As shown, the energy conversion device also includes:

[0059] The first switch 14 is connected between the first output terminal of the battery module 20 and the first terminal of the second inductor 12 , and the control module 50 is also connected to the control terminal of the first switch 14 .

[0060] The first switch 14 is used to connect the second inductor 12 to the battery module 20. When the first switch 14 is turned on, the battery module 20 charges the second inductor 12. After charging, the battery module 20 and the second inductor 12 are discharged together to achieve boost discharge. That is, by setting the first switch 14, the second inductor 12 can be used as a backup inductor for the first inductor 11.

[0061] In this embodiment, the second inductor 12 backs up the first inductor 11 by adding the first switch, thereby improving the reliability of the circuit.

[0062] Further, as an implementation method, Figure 3 As shown, the energy conversion device also includes:

[0063] The fourth switch 17 is connected between the second output terminal of the battery module 20 and the second terminal of the charge and discharge port 30 . The control module 50 is also connected to the control terminal of the fourth switch 17 .

[0064] By configuring the fourth switch 17 to cooperate with the third switch 16 , the battery module 20 is controlled to discharge externally through the charge and discharge port 30 .

[0065] Further, as an embodiment, the battery module 20 includes:

[0066] Battery;

[0067] a main positive contactor, a first end of which is connected to the positive terminal of the battery;

[0068] A pre-charge switch, a first end of which is connected to the positive electrode of the battery;

[0069] A pre-charging resistor, a first end of which is connected to the second end of the pre-charging switch;

[0070] A fuse has a first end connected to the second end of the main positive contactor and the second end of the pre-charging resistor.

[0071] The energy conversion device also includes:

[0072] The second capacitor has a first end connected to the second end of the fuse and a second end connected to the negative electrode of the battery. The first end of the second capacitor is respectively the first output end and the second output end of the battery module 20 .

[0073] The pre-charging switch and the main negative contactor are controlled to be turned on so that the battery charges the second capacitor through the pre-charging resistor and the fuse, and then the pre-charging switch is controlled to be turned off and the main positive contactor is controlled to be turned on so that the battery charges the second capacitor.

[0074] In this embodiment, a pre-charging switch and a pre-charging resistor are provided to prevent the battery from directly charging the second capacitor, and then the main positive contactor is turned on to allow the battery to charge the second capacitor, thereby ensuring the safety of the battery module.

[0075] Figure 4 An exemplary circuit diagram of an energy conversion device provided in an embodiment of the present invention. For the convenience of explaining the energy conversion device, other electrical equipment is ignored in the above figure. The energy conversion device includes a first inductor A-L1, a second inductor A-L2, a first bidirectional H-bridge, a first capacitor C1, a first switch A-KS4, a second switch A-KS3, a third switch A-KS1, and a fourth switch A-KS2. The battery module includes a battery E1, a pre-charge switch K1, a main positive contactor K2, a main negative contactor K3, a pre-charge resistor R1, a fuse FS1, a second capacitor C2, and a The positive electrode of the battery E1 is connected to the first end of the pre-charging switch K1 and the first end of the main positive contactor K2, the second end of the pre-charging switch K1 is connected to the first end of the main positive contactor K2 and the first end of the fuse FS1, the second end of the fuse FS1 is connected to the first end of the second capacitor C2, the first end of the first switch A-KS4, the first end of the third switch A-KS1, and the first end of the first inductor A-L1, the second end of the main negative contactor K3 is connected to the second end of the second capacitor C2, the first end of the fourth switch A-KS2, the second end of the first switch A-KS4 is connected to the second inductor A-L1, The first end of the inductor A-L2 is connected to the first end of the second switch A-KS3, the second end of the third switch A-KS1 is connected to the second end of the second switch A-KS3 and the first end of the charging base, the second end of the fourth switch A-KS2 is connected to the second end of the charging base, the first bidirectional H bridge includes a first bridge arm and a second bridge arm, the first bridge arm includes a first power switch A-S2 and a second power switch A-S3 connected in series, the first midpoint of the first power switch A-S2 and the second power switch A-S3 is connected to the first inductor A-L1; the second bridge arm includes a first power switch A-S2 and a second power switch A-S3 connected in series The third power switch A-S4 and the fourth power switch A-S5 are connected, and the second midpoints of the third power switch A-S4 and the fourth power switch A-S5 are connected to the second inductor A-L2; the first end of the first power switch A-S2 and the first end of the third power switch A-S4 are connected together to form the first bus terminal of the first bidirectional H bridge; the second end of the second power switch A-S3 and the second end of the fourth power switch A-S5 are connected together to form the second bus terminal of the first bidirectional H bridge, and the second bus terminal is connected to the second end of the main negative contactor K3. Please refer to the following embodiments for the specific control method of the control module.

[0076] Embodiment 2 of the present invention provides an energy conversion device based on embodiment 1, such as Figure 5 As shown, when the charging and discharging port of the energy conversion device is connected to the vehicle to be charged, the discharging method includes:

[0077] Step S11. Obtain the voltage of the battery module and the voltage of the vehicle to be charged, and select a discharge mode according to the voltage of the battery module and the voltage of the vehicle to be charged, wherein the discharge mode includes boost discharge, buck discharge and isobaric discharge.

[0078] Step S12: Control the second switch, the third switch, the first bridge arm and the second bridge arm to enable the battery module to output direct current, and enable the battery module to discharge the vehicle to be charged according to the selected discharge mode.

[0079] Select the discharge method according to the voltage of the battery module and the voltage of the vehicle to be charged, including:

[0080] When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is greater than a first preset voltage value, a step-down discharge mode is selected;

[0081] Controlling the first switch, the second switch, the third switch, the fourth switch, the first bridge arm, and the second bridge arm to enable the battery module to output direct current, and to enable the battery module to discharge the vehicle to be charged according to the selected discharge mode, including:

[0082] The first switch, the second switch, the third switch, the fourth switch, the first bridge arm and the second bridge arm are controlled to alternately perform a charging process of the battery module for the second inductor and a discharging process of the second inductor for the vehicle to be charged, so as to step down the discharge voltage of the battery module before discharging to the vehicle to be charged.

[0083] Select the discharge method according to the voltage of the battery module and the voltage of the vehicle to be charged, including:

[0084] When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is less than a second preset voltage value, a boost discharge mode is selected;

[0085] Controlling the first switch, the second switch, the third switch, the fourth switch, the first bridge arm, and the second bridge arm to enable the battery module to output direct current, and to enable the battery module to discharge the vehicle to be charged according to the selected discharge mode, including:

[0086] The first switch, the second switch, the third switch, the fourth switch, the first bridge arm and the second bridge arm are controlled to alternately perform a charging process of the battery module for the first inductor and a discharging process of the battery module and the first inductor for the vehicle to be charged, so as to boost the discharge voltage of the battery module before discharging to the vehicle to be charged.

[0087] Select the discharge method according to the voltage of the battery module and the voltage of the vehicle to be charged, including:

[0088] When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is not greater than the first preset voltage value and not less than the second preset voltage value, an isobaric discharge mode is selected;

[0089] Controlling the second switch, the third switch, the first bridge arm, and the second bridge arm to enable the battery module to output direct current, and enabling the battery module to discharge the vehicle to be charged according to the selected discharge mode, including:

[0090] The third switch is controlled to be in an on state and the second switch is controlled to be in an off state, so that the battery module discharges to the vehicle to be charged through the third switch.

[0091] Among them, the execution body of the above-mentioned discharge method is a control module. When the control module detects that the vehicle to be charged is connected to the charging and discharging port, the control module compares the voltage of the battery module and the voltage of the vehicle to be charged, and selects different discharge methods to discharge the vehicle to be charged according to the comparison result. When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is greater than the first preset voltage value, a DC boost discharge method can be used to discharge the vehicle to be charged. Since the first inductor can store electrical energy, the switching state of the first switch, the second switch, the third switch, and the fourth switch can be controlled, and the power switch in the first bridge arm and the second bridge arm is controlled to be turned on, so that the first inductor is charged through the battery module, and then the battery module and the first inductor are discharged to the vehicle to be charged. During the discharge process, since the first inductor also outputs electrical energy, boost discharge is realized. By controlling the first bridge arm and the second bridge arm, the charging process and the discharging process are alternately performed to realize boost discharge of the vehicle to be charged. When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is less than the second preset voltage value, the vehicle to be charged can be discharged by DC step-down discharge. Since the second inductor can store electric energy, the switching states of the first switch, the second switch, the third switch, and the fourth switch and the conduction of the power switches in the first bridge arm and the second bridge arm can be controlled to charge the second inductor through the battery module, and then discharge the vehicle to be charged by the second inductor. During the discharge process, since only the second inductor also outputs electric energy, step-down discharge is achieved. The charging process and the discharging process are alternately performed by controlling the first bridge arm and the second bridge arm to achieve step-down discharge of the vehicle to be charged. When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is not greater than the first preset voltage value and not less than the second preset voltage value, the equal-pressure discharge mode is selected, and the battery of the charging vehicle is directly charged through the battery module.

[0092] The technical solution of the embodiment of the present invention is specifically described below through a specific circuit structure:

[0093] Figure 6An exemplary circuit diagram of vehicle-to-vehicle charging provided in an embodiment of the present invention, vehicle A includes a first battery module, a first energy device, a first bidirectional H-bridge, and a first charging station. The first energy conversion device includes a first inductor A-L1, a second inductor A-L2, a first bidirectional H-bridge, a first capacitor C1, a first switch A-KS4, a second switch A-KS3, a third switch A-KS1, and a fourth switch A-KS2. The first battery module includes a battery E1, a pre-charging switch K1, a main positive contactor K2, a main negative contactor K3, a pre-charging resistor R1, and a fuse FS1. , a second capacitor C2, a positive electrode of the battery E1 is connected to a first end of the pre-charging switch K1 and a first end of the main positive contactor K2, a second end of the pre-charging switch K1 is connected to a first end of the main positive contactor K2 and a first end of the fuse FS1, a second end of the fuse FS1 is connected to a first end of the second capacitor C2, a first end of the first switch A-KS4, a first end of the third switch A-KS1, a first end of the first inductor A-L1, a second end of the main negative contactor K3 is connected to a second end of the second capacitor C2, a first end of the fourth switch A-KS2, a second end of the first switch A-KS4 The first end of the first inductor A-L2 is connected to the first end of the second switch A-KS3, the second end of the third switch A-KS1 is connected to the second end of the second switch A-KS3 and the first end of the charging base, the second end of the fourth switch A-KS2 is connected to the second end of the charging base, the first bidirectional H-bridge includes a first bridge arm and a second bridge arm, the first bridge arm includes a first power switch A-S2 and a second power switch A-S3 connected in series, the first midpoint of the first power switch A-S2 and the second power switch A-S3 is connected to the first inductor A-L1; the second bridge arm includes The third power switch A-S4 and the fourth power switch A-S5 are connected in series, and the second midpoints of the third power switch A-S4 and the fourth power switch A-S5 are connected to the second inductor A-L2; the first end of the first power switch A-S2 and the first end of the third power switch A-S4 are connected together to form the first bus terminal of the first bidirectional H-bridge; the second end of the second power switch A-S3 and the second end of the fourth power switch A-S5 are connected together to form the second bus terminal of the first bidirectional H-bridge, and the second bus terminal is connected to the second end of the main negative contactor K3.

[0094] Vehicle B includes a second battery module, a second energy device, a second bidirectional H-bridge, and a second charging station. The second energy conversion device includes a third inductor B-L1, a fourth inductor B-L2, a second bidirectional H-bridge, a third capacitor C3, a fifth switch B-S1, a sixth switch B-KS3, a seventh switch B-KS1, and an eighth switch B-KS2. The second battery module includes a battery E2, a pre-charging switch K4, a main positive contactor K5, a main negative contactor K6, a pre-charging resistor R2, a fuse FS2, and a fourth capacitor C4. The positive electrode of the battery E2 is connected to the first end of the pre-charging switch K4 and the main positive contactor. The first end of the pre-charge switch K5 is connected to the first end of the pre-charge resistor R2, the second end of the pre-charge resistor R2 is connected to the first end of the main positive contactor K5 and the first end of the fuse FS2, the second end of the fuse FS2 is connected to the first end of the fourth capacitor C4, the first end of the fifth switch B-S1, the first end of the eighth switch B-KS2, and the first end of the third inductor B-L1, the second end of the main negative contactor K6 is connected to the second end of the fourth capacitor C4, the first end of the seventh switch B-KS1, the second end of the fifth switch B-S1 is connected to the first end of the fourth inductor B-L2 and ... eighth switch B-KS2, the second end of the fifth switch B-S2 is connected to the first end of the fourth inductor B-L2 and the first end of the eighth switch B-L1, the second end of the fifth switch B-S1 is connected to the first end of the fourth inductor B-L2 and the first end of the eighth switch B-KS2, the second end of the fifth switch B-S2 is connected to the first end of the fourth inductor The first end of the sixth switch B-KS3, the second end of the sixth switch B-KS3 is connected to the second end of the eighth switch B-KS2 and the first end of the second charging base, the second end of the first switch B-KS1 is connected to the second end of the second charging base, the second bidirectional H bridge includes a third phase bridge arm and a fourth phase bridge arm, the third phase bridge arm includes a fifth power switch B-S2 and a sixth power switch B-S3 connected in series, the first midpoint of the fifth power switch B-S2 and the sixth power switch B-S3 is connected to the third inductor B-L1; the fourth phase bridge arm includes a seventh power switch B-S4 connected in series and the eighth power switch B-S5, the second midpoints of the seventh power switch B-S4 and the eighth power switch B-S5 are connected to the fourth inductor B-L2; the first end of the fifth power switch B-S2 and the first end of the seventh power switch B-S4 are connected together to form the first bus terminal of the second bidirectional H-bridge; the second end of the sixth power switch B-S3 and the second end of the eighth power switch B-S5 are connected together to form the second bus terminal of the second bidirectional H-bridge, the second bus terminal is connected to the second end of the main negative contactor K6, and a third capacitor is also connected between the first bus terminal and the second bus terminal.

[0095] like Figure 6As shown, after the two vehicles complete the physical connection, the vehicle activates the V2V mode, prohibits the vehicle from entering the driving mode, and establishes CAN handshake communication. The vehicle battery voltage / SOC and other information are sent through CAN, and the vehicle with a lower SOC is automatically identified as the vehicle being charged, and the vehicle with a higher SOC is the vehicle providing charging energy. The vehicle providing charging energy selects the charging mode according to the battery voltage of the vehicle being charged. For example, vehicle A is the vehicle providing charging, and vehicle B is the vehicle to be charged. When the battery voltage of vehicle A is greater than the battery voltage of vehicle B, it enters the step-down discharge mode. When the battery voltage of vehicle A is equal to the battery voltage of vehicle B, it enters the equal-voltage discharge mode. When the battery voltage of vehicle A is less than the battery voltage of vehicle B, it enters the boost discharge mode.

[0096] Working mode 1, boost discharge mode:

[0097] Car A is a vehicle with a voltage platform V1, and car B is a vehicle with a voltage platform V2, where V1 < V2. Car A discharges and charges car B. Figure 7 As shown, the control module in vehicle A controls the main positive contactor K2, the main negative contactor K3, the first switch A-S1, and the third switch A-KS1 to be disconnected, controls the second switch A-KS3 and the fourth switch A-KS2 to be turned on, controls the bridge arms of the first power switch A-S2 and the fourth power switch A-S5 to be in the off state through the PWM control signal, controls the bridge arm of the third power switch A-S4 to be turned on, and controls the bridge arm of the second power switch A-S3 to be turned on and off alternately. The control module in vehicle B controls the main positive contactor K5, the main negative contactor K6, the seventh switch B-KS1, and the eighth switch B-KS2 to be turned on, and the remaining switches and power switches are all turned off. When the bridge arm controlling the second power switch A-S3 is in the on state, the battery E1, the main positive contactor K2, the fuse FS1, the first inductor A-L1, the second power switch A-S3, and the main negative contactor K3 form a first energy storage circuit. At this time, the battery E1 stores energy in the first inductor A-L1; Figure 8 As shown, when the bridge arm controlling the second power switch A-S3 is in the off state, the battery E1, the main positive contactor K2, the fuse FS1, the first inductor A-L1, the first power switch A-S2, the third power switch A-S4, the second inductor A-L2, the second switch A-KS3, the charging stand M1, the charging stand M2, the eighth switch B-KS2, the fuse FS2, the main positive contactor K5, the battery E2, the main negative contactor K6, the seventh switch B-KS1, the charging stand M2, the charging stand M1, the fourth switch A-KS2, and the main negative contactor K3 form a first discharge circuit, and the battery E1 and the first inductor A-L1 simultaneously boost and discharge the battery E2.

[0098] In this working mode, the second inductor A-L2 acts as a common inductor and does not store energy, the first inductor A-L1 acts as an energy storage inductor and stores energy, the bridge arm of the first power switch A-S2 is disconnected to allow energy to flow through the freewheeling diode, and the energy storage and proper charging of the first inductor A-L1 are achieved by switching the second power switch A-S3, thereby boosting the high voltage of the battery in vehicle A to a voltage suitable for charging vehicle B.

[0099] Working mode 2: Same voltage charging mode:

[0100] Car A and Car B are both vehicles with voltage platform V. Car A discharges to charge Car B. When the voltages of the two cars are the same, car-to-car charging and discharging can be completed without voltage conversion. However, there is a very high risk of directly connecting two battery packs. Therefore, the voltage of Car A is increased to before charging Car B. Therefore, the control method of this charging mode is the same as that of the boost discharge mode, which can be referred to working mode 1.

[0101] Working mode three, buck discharge mode:

[0102] like Figure 6 As shown, car A is a vehicle with voltage platform V1, and car B is a vehicle with voltage platform V2, where V1>V2. Car A discharges to charge car B, and the charging of car A and car B is connected through a V2V high-voltage connecting cable. Figure 8 As shown, in vehicle A, the control module controls the first switch A-S1 and the third switch A-KS1 to be turned off, controls the main positive contactor K2, the main negative contactor K3, the second switch A-KS3 and the fourth switch A-KS2 to be turned on, controls the bridge arms of the first power switch A-S2, the second power switch A-S3 and the fourth power switch A-S5 to be in the off state through the PWM control signal, and controls the bridge arm of the third power switch A-S4 to be turned on and off alternately. The control module in vehicle B controls the main positive contactor K5, the main negative contactor K6, the seventh switch B-KS1 and the eighth switch B-KS2 to be turned on, and the remaining switches and power switches are all turned off. Fig. 9As shown, when the bridge arm controlling the third power switch A-S4 is in the on state, when the bridge arm controlling the second power switch A-S3 is in the on state, the battery E1, the main positive contactor K2, the fuse FS1, the first inductor A-L1, the first power switch A-S2, the third power switch A-S4, the second inductor A-L2, the second switch A-KS3, the charging stand M1, the charging stand M2, the eighth switch B-KS2, the fuse FS2, the main positive contactor K5, the battery E2, the main negative contactor K6, the seventh switch B-KS1, the charging stand M2, the charging stand M1, the The fourth switch A-KS2 and the main negative contactor K3 form a second energy storage circuit, and the battery E1 charges the second inductor A-L2; when the bridge arm controlling the third power switch A-S4 is in the off state, the second inductor A-L2, the second switch A-KS3, the charging seat M1, the charging seat M2, the eighth switch B-KS2, the fuse FS2, the main positive contactor K5, the battery E2, the main negative contactor K6, the seventh switch B-KS1, the charging seat M2, the charging seat M1, and the fourth power switch A-S5 form a second discharge circuit, and the second inductor A-L2 discharges the battery E2.

[0103] In this working mode, the first inductor A-L1 acts as a common inductor and does not store energy. The first power switch A-S2 is disconnected, and energy flows through the freewheeling diode. By switching the third power switch A-S4, energy storage and proper charging of the second inductor A-L2 are achieved, and the high voltage V1 of the battery E1 is reduced to a voltage V2 suitable for charging vehicle B.

[0104] Another embodiment of the present disclosure provides a vehicle, which also includes the energy conversion device, battery module and charge and discharge port provided in the above-mentioned embodiment one, one end of the battery module and one end of the energy conversion device are connected to one end of the charge and discharge port, and the other end of the battery module and the other end of the energy conversion device are connected to the other end of the charge and discharge port.

[0105] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention.

Claims

1. An energy conversion device, characterized in that: include: A first inductor, a first end of which is connected to a first output end of the battery module; a second inductor, a first end of which is connected to the first end of the first inductor; A second switch connected between the first end of the second inductor and the first end of the charge and discharge port; A first bidirectional H-bridge, one end of which is connected to the second output end of the battery module and the second end of the charge and discharge port, and includes a first bridge arm and a second bridge arm connected in parallel, the second end of the first inductor is connected to the first bridge arm, and the second end of the second inductor is connected to the second bridge arm; a third switch connected between the first end of the first inductor and the first end of the charge and discharge port; The energy conversion device further includes a control module, which is connected to the battery module, the control end of the first bridge arm, the control end of the second bridge arm, the control end of the second switch, and the control end of the third switch. When the charging and discharging port is connected to a vehicle to be charged, the control module is used to: Acquiring the voltage of the battery module and the voltage of the vehicle to be charged, and selecting a discharge mode according to the voltage of the battery module and the voltage of the vehicle to be charged, wherein the discharge mode includes boost discharge, buck discharge and isobaric discharge; Controlling the second switch, the third switch, the first bridge arm, and the second bridge arm to enable the battery module to output direct current, and to enable the battery module to discharge the vehicle to be charged according to the selected discharge mode; The first bridge arm includes a first power switch and a second power switch connected in series, and the second end of the first inductor is connected to the second end of the first power switch and the first end of the second power switch; The second bridge arm includes a third power switch and a fourth power switch connected in series, and the second end of the second inductor is connected to the second end of the third power switch and the first end of the fourth power switch; The first end of the first power switch and the first end of the third power switch are connected together to form a first bus terminal of the first bidirectional H-bridge; the second end of the second power switch and the second end of the fourth power switch are connected together to form a second bus terminal of the first bidirectional H-bridge, and the second bus terminal is connected to the second output terminal of the battery module and the second end of the charge and discharge port; When the control module performs boost discharge, the third switch is in an off state, the second switch is in an on state, the battery module, the first inductor, the second power switch, and the vehicle to be charged form a first energy storage circuit, and the battery module, the first inductor, the second power switch, the third power switch, the second inductor, the second switch, and the vehicle to be charged form a first discharge circuit.

2. The energy conversion device according to claim 1, characterized in that: When the control module performs step-down discharge, the third switch is in an off state, the second switch is in an on state, the battery module, the first inductor, the second power switch, the third power switch, the second inductor, the second switch, and the vehicle to be charged form a second energy storage circuit, and the second inductor, the second switch, the vehicle to be charged, and the fourth power switch form a second discharge circuit.

3. The energy conversion device according to claim 1, characterized in that: When the control module performs isobaric discharge, the third switch is in an on state, the second switch is in an off state, and the battery module, the third switch, and the vehicle to be charged form a third discharge circuit.

4. The energy conversion device according to claim 1, characterized in that: It also includes: A first capacitor is connected between the first bus terminal and the second bus terminal.

5. The energy conversion device according to claim 1, characterized in that: The energy conversion device also includes: The first switch is connected between the first output terminal of the battery module and the first terminal of the second inductor, and the control module is also connected to the control terminal of the first switch.

6. The energy conversion device according to claim 1, characterized in that: The energy conversion device also includes: A fourth switch is connected between the second output end of the battery module and the second end of the charge and discharge port, and the control module is also connected to the control end of the fourth switch.

7. The energy conversion device according to claim 4, characterized in that: The first bidirectional H-bridge is connected to a motor controller, and the motor controller is connected to a motor; When the energy conversion device is in a driving state, the battery module, the first inductor, the second inductor, the first bidirectional H-bridge, the motor controller and the motor serve as part of a driving circuit; When the energy conversion device is in a discharging state, the battery module, the first inductor, the second inductor, the first bidirectional H-bridge, the second switch, the third switch, and the vehicle to be charged serve as part of a discharging circuit; The first inductor, the second inductor, and the first bidirectional H-bridge are reused in the driving circuit and the discharge circuit.

8. The energy conversion device according to claim 1, characterized in that: The battery module comprises: Battery; a main positive contactor, a first end of which is connected to the positive electrode of the battery; A pre-charge switch, a first end of which is connected to the positive electrode of the battery; a pre-charging resistor, a first end of which is connected to the second end of the pre-charging switch; A fuse has a first end connected to the second end of the main positive contactor and the second end of the pre-charging resistor.

9. The energy conversion device according to claim 1, characterized in that: The energy conversion device also includes: A second capacitor is connected between the first output terminal and the second output terminal of the battery module.

10. A discharge method for an energy conversion device, based on the energy conversion device according to claim 1, characterized in that: When the charging and discharging port of the energy conversion device is connected to a vehicle to be charged, the discharging method includes: Acquiring the voltage of the battery module and the voltage of the vehicle to be charged, and selecting a discharge mode according to the voltage of the battery module and the voltage of the vehicle to be charged, wherein the discharge mode includes boost discharge, buck discharge and isobaric discharge; The second switch, the third switch, the first bridge arm and the second bridge arm are controlled to enable the battery module to output direct current, and to enable the battery module to discharge the vehicle to be charged according to the selected discharge mode.

11. The discharge method according to claim 10, characterized in that: The step of selecting a discharge mode according to the voltage of the battery module and the voltage of the vehicle to be charged includes: When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is greater than a first preset voltage value, a step-down discharge mode is selected; Controlling the second switch, the third switch, the first bridge arm, and the second bridge arm to enable the battery module to output direct current, and enabling the battery module to discharge the vehicle to be charged according to the selected discharge mode, includes: The second switch, the third switch, the first bridge arm and the second bridge arm are controlled to alternately perform a charging process of the battery module on the second inductor and a discharging process of the second inductor on the vehicle to be charged, so as to reduce the discharge voltage of the battery module and then discharge the vehicle to be charged.

12. The discharge method according to claim 10, characterized in that: The step of selecting a discharge mode according to the voltage of the battery module and the voltage of the vehicle to be charged includes: When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is less than a second preset voltage value, a boost discharge mode is selected; Controlling the second switch, the third switch, the first bridge arm, and the second bridge arm to enable the battery module to output direct current, and enabling the battery module to discharge the vehicle to be charged according to the selected discharge mode, includes: The second switch, the third switch, the first bridge arm and the second bridge arm are controlled so that the battery module charges the first inductor and the battery module and the first inductor discharge the vehicle to be charged alternately, so as to boost the discharge voltage of the battery module before discharging the vehicle to be charged.

13. The discharge method according to claim 10, characterized in that: The step of selecting a discharge mode according to the voltage of the battery module and the voltage of the vehicle to be charged includes: When it is detected that the difference between the voltage of the battery module and the voltage of the vehicle to be charged is not greater than a first preset voltage value and not less than a second preset voltage value, selecting an isobaric discharge mode; Controlling the second switch, the third switch, the first bridge arm, and the second bridge arm to enable the battery module to output direct current, and enabling the battery module to discharge the vehicle to be charged according to the selected discharge mode, includes: The third switch is controlled to be in an on state and the second switch is controlled to be in an off state, so that the battery module discharges the vehicle to be charged through the third switch.

14. A vehicle, characterized in that: The vehicle also includes an energy conversion device, a battery module and a charge and discharge port as described in any one of claims 1 to 9, one end of the battery module and one end of the energy conversion device are connected to one end of the charge and discharge port, and the other end of the battery module and the other end of the energy conversion device are connected to the other end of the charge and discharge port.

Images