On-vehicle charging system, control method and electric vehicle

Abstract

The present invention provides an on-board charging system, a control method and an electric vehicle, the system comprising a six-phase inverter, a six-phase motor, a first capacitor, a second capacitor and a charging interface; the six-phase inverter comprises a first group of inverters and a second group of inverters, the six-phase motor comprises a first group of motors and a second group of motors, the output end of the first group of inverters is connected to the first group of motors, and the output end of the second group of inverters is connected to the second group of motors; the DC input end of the first group of inverters is connected in parallel with the first capacitor and then connected to the output end of the power battery; the DC input end of the second group of inverters is connected in parallel with the second capacitor. The on-board charging system of the embodiment of the present invention combines the functions of the motor and the on-board charger into a powertrain, greatly improving the integration of the high-voltage part of the electric vehicle, reducing the difficulty of the whole vehicle design, reducing the cost, and enhancing the compatibility of the electric vehicle with the charging power supply.

Description

Technical Field

[0001] The present invention relates to the design field of a driving motor and a controller thereof and an on-board charger, and in particular to an on-board charging system, a control method and an electric vehicle. Background Art

[0002] There are many patents about six-phase permanent magnet synchronous motors, but these patents only explain the advantages of six-phase permanent magnet synchronous motors from the perspective of drive motors, and do not reuse the six-phase permanent magnet synchronous motor as part of the on-board charger. Therefore, they are very different from this patent or even completely different. The journal "Six-phase Motor Characteristics and Its Application in the Automotive Industry" details the current patent distribution of six-phase permanent magnet synchronous motors. Summary of the invention

[0003] The embodiments of the present invention provide an on-board charging system, a control method and an electric vehicle, which are used to solve the problem in the prior art that a six-phase permanent magnet synchronous motor is not used as part of an on-board charger to reuse its functions, and the problem that the electric vehicle has poor fast charging compatibility.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] An embodiment of the present invention provides a vehicle-mounted charging system, including:

[0006] A six-phase inverter, a six-phase motor, a first capacitor, a second capacitor and a charging interface;

[0007] The six-phase inverter includes a first group of inverters and a second group of inverters, the six-phase motors include a first group of motors and a second group of motors, the output end of the first group of inverters is connected to the first group of motors, and the output end of the second group of inverters is connected to the second group of motors;

[0008] Wherein, the DC input end of the first group of inverters is connected in parallel with the first capacitor and then connected to the output end of the power battery;

[0009] The DC input terminal of the second group of inverters is connected in parallel with the second capacitor, wherein:

[0010] The positive input terminal of the DC input terminals of the second group of inverters is connected to the positive output terminal of the output terminals of the power battery through the first relay;

[0011] A negative input terminal of the DC input terminals of the second group of inverters is connected to a negative output terminal of the output terminals of the power battery through a second relay;

[0012] The positive input terminal of the DC input terminal of the second inverter group is connected to the positive terminal of the charging interface through the third relay;

[0013] The negative input terminal of the DC input terminals of the second inverter group is connected to the negative terminal of the charging interface through the fourth relay.

[0014] Furthermore, the charging interface includes: a DC charging interface and an AC charging interface.

[0015] The embodiment of the present invention further provides a vehicle charging system control method, which is applied to the vehicle charging system as described above, and includes:

[0016] When the vehicle is in a driving state, the first relay and the second relay are closed, and the third relay and the fourth relay are opened;

[0017] The six-phase inverter converts the direct current output by the power battery into alternating current and provides it to the six-phase motor.

[0018] Furthermore, the vehicle charging system control method further includes:

[0019] When the vehicle is in a charging state, when it is detected that the power battery is charged by the DC charger, the first relay, the second relay, the third relay and the fourth relay are closed;

[0020] The DC charger is received to charge the power battery.

[0021] Furthermore, the vehicle charging system control method further includes:

[0022] When the vehicle is in a charging state, when it is detected that the power battery is charged by the AC charger, the first relay and the second relay are disconnected, and the third relay and the fourth relay are closed;

[0023] Receive the AC charger to charge the power battery.

[0024] An embodiment of the present invention further provides an electric vehicle, comprising a power battery and the on-board charging system as described above.

[0025] The beneficial effects of the present invention are:

[0026] The vehicle-mounted charging system of the embodiment of the present invention adopts the original motor and inverter system of the vehicle as a high-power charger, changes the motor from a traditional three-phase motor to a six-phase motor, and changes the inverter from a traditional three-phase inverter to a six-phase inverter. Only a small number of components are added, so that the motor inverter has the function of high-power, large-amplitude DC conversion, realizes safe and fast charging on the vehicle, and eliminates the fast-charging high-current relay of the power distribution unit and its corresponding high-current high-voltage connector, AC slow-charging relay and its corresponding high-voltage connector, AC slow-charging charging seat and its corresponding charging module and wiring harness and all wiring harnesses, copper bars and cooling systems connected to the above components. Combining the functions of the motor and the vehicle-mounted charger into one powertrain greatly improves the integration of the high-voltage part of the electric vehicle, greatly reduces the difficulty of vehicle design, and significantly reduces the volume, weight and cost of the vehicle. At the same time, the compatibility of electric vehicles with charging power sources is enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram showing a vehicle-mounted charging system according to an embodiment of the present invention;

[0028] Figure 2 A schematic diagram showing the steps of a vehicle charging system control method according to an embodiment of the present invention;

[0029] Figure 3 A schematic diagram showing a vehicle-mounted charging system according to an embodiment of the present invention in a first state;

[0030] Figure 4 A schematic diagram showing a vehicle-mounted charging system according to an embodiment of the present invention in a second state;

[0031] Figure 5 A schematic diagram showing a vehicle charging system according to an embodiment of the present invention in a third state. DETAILED DESCRIPTION

[0032] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] The present invention aims to solve the problems in the prior art that a six-phase permanent magnet synchronous motor is not used as part of an on-board charger to reuse its functions, and that electric vehicles have poor fast charging compatibility, and provides an on-board charging system, a control method and an electric vehicle.

[0034] like Figure 1 As shown, an embodiment of the present invention provides a vehicle charging system, including:

[0035] A six-phase inverter, a six-phase motor, a first capacitor, a second capacitor and a charging interface;

[0036] The six-phase inverter includes a first inverter group 11 and a second inverter group 12, and the six-phase motor includes a first motor group 21 and a second motor group 22, the output end of the first inverter group 11 is connected to the first motor group 21, and the output end of the second inverter group 12 is connected to the second motor group 22;

[0037] The DC input end of the first inverter group 11 is connected in parallel with the first capacitor and then connected to the output end of the power battery;

[0038] The DC input terminal of the second inverter group 12 is connected in parallel with the second capacitor, wherein:

[0039] The positive input terminal of the DC input terminals of the second group of inverters 12 is connected to the positive output terminal of the output terminals of the power battery through the first relay;

[0040] The negative input terminal of the DC input terminal of the second group of inverters 12 is connected to the negative output terminal of the output terminal of the power battery through the second relay;

[0041] The positive input terminal of the DC input terminal of the second group of inverters 12 is connected to the positive terminal of the charging interface through the third relay;

[0042] The negative input terminal of the DC input terminals of the second group of inverters 12 is connected to the negative terminal of the charging interface through the fourth relay.

[0043] Optionally, the charging interface includes: a DC charging interface and an AC charging interface.

[0044] It should be noted that each set of three-phase inverters drives the three-phase windings of the corresponding motor; and there is no electrical connection between the two sets of inverters and the windings, that is, they are isolated from each other. The charging and receiving ends are completely isolated to ensure insulation performance, greatly reducing the safety hazards caused by leakage.

[0045] Each inverter group includes six triode transistors, the first triode transistor is connected in series with the second triode transistor, the third triode transistor is connected in series with the fourth triode transistor, and the fifth triode transistor is connected in series with the sixth triode transistor.

[0046] The collector of the first triode transistor is connected to the collector of the third triode transistor and the collector of the fifth triode transistor, and the emitter of the second triode transistor is connected to the emitter of the fourth triode transistor and the emitter of the sixth triode transistor.

[0047] The seventh triode transistor is connected in series with the eighth triode transistor, the ninth triode transistor is connected in series with the eleventh triode transistor, and the eleventh triode transistor is connected in series with the twelfth triode transistor.

[0048] The collector of the seventh triode transistor is connected to the collector of the ninth triode transistor and the collector of the eleventh triode transistor, and the emitter of the eighth triode transistor is connected to the emitter of the eleventh triode transistor and the emitter of the twelfth triode transistor.

[0049] like Figure 2 and Figure 3 As shown, an embodiment of the present invention further provides a vehicle charging system control method, which is applied to the vehicle charging system as described above, comprising:

[0050] Step 21, when the vehicle is in a driving state, closing the first relay and the second relay, and opening the third relay and the fourth relay;

[0051] Step 22, converting the direct current output by the power battery into alternating current through the six-phase inverter, and providing it to the six-phase motor.

[0052] When the vehicle is in driving state, the first relay and the second relay are closed, and the third relay and the fourth relay are opened. At this time, the six-phase inverter is equivalent to a motor driver, which converts the direct current of the battery into alternating current to provide power for the motor and drive the vehicle to move.

[0053] like Figure 4 As shown, the vehicle charging system control method also includes:

[0054] When the vehicle is in a charging state, when it is detected that the power battery is charged by the DC charger, the first relay, the second relay, the third relay and the fourth relay are closed;

[0055] The DC charger is received to charge the power battery.

[0056] When the vehicle is in a charging state and it is detected that the power battery is charged by a DC charger, that is, the power supply is a DC charging pile of 250V to 750V, the first relay, the second relay, the third relay and the fourth relay are closed, and the charging interface is a DC charging interface.

[0057] The vehicle-mounted charging system control system of the embodiment of the present invention can also be charged by unprocessed DC power directly from solar panels or energy storage, which greatly improves the compatibility of electric vehicles with charging power sources.

[0058] like Figure 5 As shown, the vehicle charging system control method further includes:

[0059] When the vehicle is in a charging state, when it is detected that the power battery is charged by the AC charger, the first relay and the second relay are disconnected, and the third relay and the fourth relay are closed;

[0060] Receive the AC charger to charge the power battery.

[0061] When the vehicle is in a charging state and it is detected that the power battery is charged by an AC charger, that is, when the power source is an ordinary AC charging pile, for example, using standard 6.6kw AC power, 110V to 240VAC single-phase AC power, or 208V to 480VAC three-phase AC power for charging, the first relay and the second relay are disconnected, and the third relay and the fourth relay are closed, and the charging interface is an AC charging interface.

[0062] An embodiment of the present invention further provides an electric vehicle, comprising a power battery and the on-board charging system as described above.

[0063] The vehicle-mounted charging system of the embodiment of the present invention adopts the original motor and inverter system of the vehicle as a high-power charger, changes the motor from a traditional three-phase motor to a six-phase motor, and changes the inverter from a traditional three-phase inverter to a six-phase inverter. Only a small number of components are added, so that the motor inverter has the function of high-power, large-amplitude DC conversion, realizes safe and fast charging on the vehicle, and eliminates the fast-charging high-current relay of the power distribution unit and its corresponding high-current high-voltage connector, AC slow-charging relay and its corresponding high-voltage connector, AC slow-charging charging seat and its corresponding charging module and wiring harness and all wiring harnesses, copper bars and cooling systems connected to the above components. Combining the functions of the motor and the vehicle-mounted charger into one powertrain greatly improves the integration of the high-voltage part of the electric vehicle, greatly reduces the difficulty of vehicle design, and significantly reduces the volume, weight and cost of the vehicle. At the same time, the compatibility of electric vehicles with charging power sources is enhanced.

[0064] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary personnel in this technical field, several improvements and modifications can be made without departing from the principles described in the present invention. These improvements and modifications are also within the scope of protection of the present invention.

Claims

1. A vehicle charging system, characterized in that: include: A six-phase inverter, a six-phase motor, a first capacitor, a second capacitor and a charging interface; The six-phase inverter comprises a first group of inverters (11) and a second group of inverters (12); The six-phase motor comprises a first group of motors (21) and a second group of motors (22); The output end of the first inverter group (11) is connected to the first motor group (21), and the output end of the second inverter group (12) is connected to the second motor group (22); Wherein, the DC input end of the first group of inverters (11) is connected in parallel with the first capacitor and then connected to the output end of the power battery; The DC input end of the second inverter group (12) is connected in parallel with the second capacitor, and is connected to the power battery and the charging interface; Wherein, the charging interface includes: a DC charging interface and an AC charging interface; The second inverter group is connected to the power battery and includes: A positive input terminal among the DC input terminals of the second group of inverters (12) is connected to a positive output terminal among the output terminals of the power battery through a first relay; A negative input terminal of the DC input terminals of the second inverter group (12) is connected to a negative output terminal of the output terminals of the power battery through a second relay; The second inverter group is connected to the charging interface and includes: A positive input terminal of the DC input terminals of the second inverter (12) is connected to a positive terminal of the charging interface through a third relay; The negative input terminal of the DC input terminal of the second inverter (12) is connected to the negative terminal of the charging interface through the fourth relay.

2. A vehicle charging system control method, characterized in that: The vehicle-mounted charging system according to claim 1 comprises: When the vehicle is in a driving state, the first relay and the second relay are closed, and the third relay and the fourth relay are opened; The six-phase inverter converts the direct current output by the power battery into alternating current and supplies it to the six-phase motor; When the vehicle is in a charging state, when it is detected that the power battery is charged by the DC charger, the first relay, the second relay, the third relay and the fourth relay are closed; Receiving charging of the power battery by the DC charger; When the vehicle is in a charging state, when it is detected that the power battery is charged by the AC charger, the first relay and the second relay are disconnected, and the third relay and the fourth relay are closed; Receive the AC charger to charge the power battery.

3. An electric vehicle, characterized in that: It includes a power battery and also includes the on-board charging system as claimed in claim 1.

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