Vehicle voltage conversion system, and vehicle voltage conversion controller and control method therefor

Abstract

The present application relates to a vehicle voltage conversion system and a method therefor, a vehicle voltage conversion controller and a control method therefor, a computer-readable storage medium, an electronic device, and a vehicle. The vehicle voltage conversion system in the present application comprises a three-phase electric motor, an electric motor driving control circuit, a charging port and a vehicle voltage conversion controller. The electric motor driving control circuit is connected between a traction battery of a vehicle and the three-phase electric motor, and comprises three switch bridge arms, which are connected in parallel. The charging port comprises a first output end and a second output end, wherein the first output end is connected, by means of each winding of the three-phase electric motor, to the midpoint of the switch bridge arm corresponding to each winding, and the second output end is connected to one electrode of the traction battery. The vehicle voltage conversion controller is configured to select, according to a rotor position angle of the three-phase electric motor and by means of controlling the turning-on and turning-off of the three switch bridge arms, two-phase windings which generate a larger inductance value in the windings of the three-phase electric motor, so as to perform voltage conversion between the charging port and the traction battery.

Description

Vehicle voltage conversion system, vehicle voltage conversion controller and control method thereof Technical Field

[0001] The present application relates to the field of electric energy conversion, and more specifically, to a vehicle voltage conversion system, a vehicle voltage conversion controller and a control method thereof, a computer-readable storage medium, an electronic device, and a vehicle. Background Art

[0002] Currently, there's a mismatch between the supply voltage of DC charging facilities and the charging voltage of electric vehicles. For example, the main high-voltage system platforms for electric vehicles currently on the market operate at voltages of 400V and 800V, but charging facilities typically operate at 500V, 750V, or 1000V, making them incapable of directly charging or fully charging electric vehicles. Therefore, a corresponding voltage conversion control device and method are needed, with the goal of reducing costs, improving motor inductance utilization, and lowering voltage conversion losses and heat generation.

[0003] Summary of the Invention

[0004] In view of the above problems, the present invention aims to provide a vehicle voltage conversion system, a vehicle voltage conversion controller and a control method thereof, a computer-readable storage medium, an electronic device, and a vehicle.

[0005] According to a first aspect of the present application, a vehicle voltage conversion system is provided, comprising a three-phase motor, a motor drive control circuit, a charging port, and a vehicle voltage conversion controller. The charging port includes a first output terminal and a second output terminal. The first output terminal is connected to the midpoint of a switching bridge arm corresponding to each winding of the three-phase motor via each winding, and the second output terminal is connected to one terminal of a power battery. The vehicle voltage conversion controller is configured to select two phases of the three-phase motor windings with greater inductance by controlling the conduction and disconnection of the three switching bridge arms based on the rotor position angle of the three-phase motor, thereby performing voltage conversion between the charging port and the power battery.

[0006] According to an embodiment of the present invention, a vehicle voltage conversion system comprises a switching bridge arm including two switching modules connected in series, each switching module including a MOS transistor switch and a diode connected in parallel, and a vehicle voltage conversion controller is further configured to control a switching control signal of the MOS transistor switch to determine one of the MOS transistor switch and the diode for turning on the switching module.

[0007] According to a vehicle voltage conversion system according to one embodiment of the present invention, the vehicle voltage conversion controller is further configured to distribute the current of the selected two-phase winding according to the rotor position angle, so that during the voltage conversion process, the magnetic flux composed of the two-phase winding does not have a direct axis component perpendicular to the rotor magnetic flux direction of the three-phase motor.

[0008] According to a vehicle voltage conversion system according to one embodiment of the present invention, the vehicle voltage conversion controller is further configured to distribute the current of the selected two-phase windings according to the rotor position angle, so that during the voltage conversion process, the direct-axis component of the current vector composed of the two-phase windings is equal in amplitude to the magnetic flux of the permanent magnet of the three-phase motor divided by the amplitude of the difference between the direct-axis and quadrature-axis inductances of the three-phase motor.

[0009] According to an embodiment of the present invention, the vehicle voltage conversion system comprises the vehicle voltage conversion controller further configured to stagger the phases of the control signals of the switches of the switching arms in the two-phase windings.

[0010] According to a second aspect of the present application, a vehicle voltage conversion controller is provided. The vehicle voltage conversion controller is configured to select two phases of the three-phase motor windings with greater inductance to perform voltage conversion between the vehicle's charging port and the power battery by controlling the on / off switching of the switching bridge arms of the motor drive control circuit based on the rotor position angle of the vehicle's three-phase motor. The charging port includes a first output terminal and a second output terminal. The first output terminal is connected to the midpoint of the switching bridge arm corresponding to each winding of the three-phase motor via each winding of the three-phase motor, and the second output terminal is connected to one terminal of the power battery.

[0011] According to a third aspect of the present application, a vehicle is provided, comprising a vehicle voltage conversion controller or a vehicle voltage conversion system according to any one of the aforementioned embodiments.

[0012] According to a fourth aspect of the present application, a voltage conversion control method is provided. The control method includes the following steps: receiving a detected rotor position angle of a three-phase motor of a vehicle; and, based on the rotor position angle, controlling the on / off switching of a switch bridge arm of a motor drive control circuit of the three-phase motor to select two phase windings of the three-phase motor with a greater inductance to perform voltage conversion between a charging port of the vehicle and a power battery.

[0013] According to a control method according to an embodiment of the present invention, a switch bridge arm includes two switch modules connected in series, each switch module includes a MOS transistor switch and a diode connected in parallel, and controlling the switch of the switch bridge arm includes: determining one of the MOS transistor switch and the diode for turning on the switch module.

[0014] According to an embodiment of the present invention, the control method further comprises: distributing the current of the selected two-phase windings according to the rotor position angle, so that during the conversion process, the flux linkage formed by the two-phase windings does not contain a direct axis component perpendicular to the rotor flux linkage direction of the three-phase motor. The charging port includes a first output terminal and a second output terminal, the first output terminal being connected to the midpoint of the switch bridge arm corresponding to each winding of the three-phase motor through each winding, and the second output terminal being connected to one pole of the power battery.

[0015] According to a control method according to an embodiment of the present invention, the method further includes: distributing the current of the selected two-phase windings according to the rotor position angle, so that during the transformation process, the direct-axis component of the current vector composed of the two-phase windings is equal in amplitude to the magnetic flux of the permanent magnet of the three-phase motor divided by the amplitude of the difference between the direct-axis and quadrature-axis inductances of the three-phase motor.

[0016] According to an embodiment of the control method of the present invention, the method further comprises: staggering the phases of control signals of switches of the switching bridge arms in the two-phase windings.

[0017] According to a fifth aspect of the present application, a computer-readable storage medium is provided, wherein instructions are stored in the computer-readable storage medium, and when the instructions are executed by a processor, the processor executes the voltage conversion control method according to any one of the aforementioned embodiments.

[0018] According to a sixth aspect of the present application, an electronic device is provided, comprising a memory and a processor, wherein the memory stores instructions, and when the instructions are executed by the processor, the processor implements the voltage conversion control method according to any of the aforementioned embodiments.

[0019] This application utilizes the electric vehicle's own motor drive control circuitry and windings to perform voltage conversion control, reducing hardware costs for voltage conversion control. This can be accomplished using only two-phase windings, reducing winding losses. The selected two-phase windings maximize utilization of the motor's internal inductance, generating little or no additional torque, and alleviating heating issues. Furthermore, the motor can be further optimized to achieve zero torque output, reducing eddy current losses, minimizing the impact of input and output ripple, and improving charging efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other objects and advantages of the present application will become more fully apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein the same or similar elements are denoted by the same reference numerals.

[0021] FIG1 shows a schematic diagram of a vehicle voltage conversion system 100 according to one or more embodiments of the present application.

[0022] FIG2 is a schematic diagram showing an example correspondence between rotor position angle and winding selection according to one or more embodiments of the present application.

[0023] FIG3 is a schematic diagram showing the corresponding relationship between the rotor position angle θ and the self-inductance of the three-phase winding.

[0024] FIG. 4A exemplarily shows a schematic diagram of two-phase winding current distribution adopted by sector 3 in FIG. 2 .

[0025] FIG4B exemplarily shows a schematic diagram of two-phase winding current distribution adopted by sector 2 in FIG2 .

[0026] FIG5 is a schematic diagram showing waveforms of operating signals of the switch modules corresponding to the selected two-phase windings.

[0027] FIG6 is a schematic diagram showing the distribution of current vectors at two d-axis angles.

[0028] FIG7 shows a flow chart of a voltage conversion control method 700 according to one or more embodiments of the present application. DETAILED DESCRIPTION

[0029] The description of the following specific embodiments is merely exemplary in nature and is not intended to limit the disclosed technology or the application and use of the disclosed technology. In addition, there is no intention to be bound by any express or implied theory presented in the foregoing technical field, background technology or the following specific embodiments.

[0030] In the following detailed description of the embodiments, numerous specific details are set forth to provide a more thorough understanding of the disclosed technology. However, it will be apparent to one of ordinary skill in the art that the disclosed technology can be practiced without these specific details. In other instances, well-known features are not described in detail to avoid unnecessarily complicating the description.

[0031] Terms such as “comprise” and “include” indicate that in addition to the units and steps directly and explicitly stated in the specification, the technical solution of the present invention does not exclude the situation where it has other units and steps that are not directly or explicitly stated.

[0032] Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

[0033] FIG1 shows a schematic diagram of a vehicle voltage conversion system 100 including a vehicle voltage conversion controller according to one or more embodiments of the present application. The voltage conversion system 100 is connected to a power battery and includes a charging port 110, a three-phase motor 120, a motor drive control circuit 130, and a vehicle voltage conversion controller 140. The voltage conversion system 100 utilizes the vehicle's own motor drive control circuit 130 to convert external electrical energy delivered by the vehicle's charging port 110 into a voltage suitable for charging the power battery, or to convert the output voltage from the power battery for output.

[0034] In Figure 1, the motor drive control circuit 130 is connected to the two poles of the vehicle power battery and includes three switch bridge arms and corresponding six switch modules (Q1-Q6). Each switch bridge arm is composed of two switch modules connected in series. The midpoint of each switch bridge arm is connected to the first output port of the charging port 110 through a winding, and the second output port of the charging port 110 is connected to one pole (for example, the negative pole) of the power battery. A capacitor can be connected in parallel to the power battery. It can be understood that the connections of the power battery, motor drive circuit and winding (represented by inductance symbols) in Figure 1 are all conventional circuit designs and configurations of electric vehicle drive motors in the field, and will not be repeated here.

[0035] However, as shown in FIG1 , in terms of circuit structure, the present application further connects the first output port of the charging port to the other end of each phase winding, so that the first output port is connected to the midpoint of the switch bridge arm corresponding to each winding via each winding of the motor. In other words, the same end of the three windings is connected and commonly connected to the first output port of the charging port. Such a circuit structure can maximize the use of winding inductance for voltage conversion, and the first output port is connected to the same end of each phase winding, which also advantageously utilizes the hardware layout of the vehicle electric drive, without the need for complex circuit design and connection to the other end of each winding (i.e., the left end of each inductance symbol in FIG1 ) through the winding housing or barrier plate. At the same time, the present application does not need to set up an additional switch for winding selection, but can use the switch of the motor drive circuit itself.

[0036] Specifically, the charging port 110 includes a first output terminal and a second output terminal for providing power input from, for example, an external charging station. The first output terminal of the charging port 110 is connected to the midpoint of each switching arm of the motor drive control circuit 130 corresponding to each phase. In other words, the first output terminal is connected to the midpoint of each switching arm of the motor drive control circuit for each phase. Furthermore, the connection line between the midpoint of each switching arm and the first input terminal of the charging port 110 is connected to the winding of the corresponding phase of the motor 120. In addition to the above connections to the charging port 110, the two input terminals of the motor drive control circuit 130 are connected to the two poles of the power battery to obtain power from the vehicle power battery during normal driving scenarios and thereby drive the three-phase motor. The vehicle voltage conversion controller 140 is connected to the motor drive control circuit 130 and provides it with control signals for each switch. Based on the current rotor position angle detected for the motor 120, the vehicle voltage conversion controller 140 selects and activates the corresponding two switching arms in the motor drive control circuit 130 to control the voltage conversion from the charging port 110 to the two poles of the power battery. For example, after the vehicle voltage conversion controller 140 receives the rotor position angle of the motor detected by the vehicle motor rotor detection device, it selects the switching action of the switching bridge arm of the two-phase winding according to the size of the rotor position angle (for example, turning on the control switch of the two-phase winding by the motor drive control circuit and turning off the switch of the other phase) to enable the two switching bridge arms to implement voltage conversion, wherein the switching action includes turning on the switch and turning off the switch.

[0037] FIG2 shows a schematic diagram of an example correspondence between the rotor position angle and winding selection according to one or more embodiments of the present application, wherein a three-phase motor includes, for example, three-phase windings A / B / C. For example, the direction of the magnetic field of the motor phase A winding is 0°, and it rotates counterclockwise for one revolution. The range from 330° to 30° is sector 1, and sectors 1 to 6 are named counterclockwise. Therefore, for example, when the motor rotor position angle θ is in the sector 1 range, the B-phase winding and the C-phase winding are selected for voltage conversion. Thus, based on the currently detected rotor position angle, it can be determined which two switching bridge arms (and corresponding windings) should be enabled to make the corresponding two-phase winding work while the other phase winding does not work. This winding selection can make the direction of the composite magnetic field generated by the selected two sets of windings roughly centered on the quadrature axis (q-axis) of the motor. It will be understood that the above sector division is only exemplary, and different sector sizes and angle division methods can also be designed based on the principle that the direction of the composite magnetic field generated by the selected two sets of windings is roughly centered on the quadrature axis of the motor. For example, as shown in Figure 3, the relationship between the corresponding rotor position angle θ (radians or electrical degrees, within the range of 2π) and the three-phase winding self-inductance LA(θ), LB(θ) and LC(θ) is shown. According to the change of self-inductance with the rotor position angle, 6 sectors can be divided. In each sector, the self-inductance values ​​of the corresponding two-phase windings are always greater than that of the remaining one-phase winding.

[0038] By using the vehicle voltage conversion controller 140 to perform the above control, the vehicle's own motor drive control circuit 130 can be used to perform voltage conversion so that the external electric energy voltage is suitable for charging the power battery, saving the installation of additional voltage conversion modules / equipment, and the inductance is generated by the winding itself, thereby further reducing the hardware volume and weight of the vehicle control system. More importantly, the vehicle voltage conversion controller 130 in this application only selects two-phase windings and corresponding switching modules to perform electric energy voltage conversion, thereby saving the use and loss of one winding. In addition, the sector division and winding selection also take into account the direction of the magnetic field and the motor's cross axis, effectively reducing or eliminating the generation of additional torque and improving the safety of the voltage conversion process.

[0039] Preferably, each switch module can also be connected in parallel with a diode as shown in Figure 1. That is, each switch bridge arm can include two switch modules connected in series, and each switch module includes a MOS tube (i.e., Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) / Metal Oxide Semiconductor Field Effect Transistor) switch and a diode connected in parallel. The vehicle voltage conversion controller 140 is also configured to control the switch control signal of the MOS tube switch to determine one of the MOS tube switch and the diode for turning on the switch module. In this way, the control signal of the switch can be determined as needed. For example, in Q1, it is possible to choose to turn on the MOS tube and turn off the diode, or to choose to turn on the diode and turn off the MOS tube. The former uses the MOS tube channel to turn on the circuit with less loss. It can be understood that the present application is not limited to the use of MOS tube switches, but other types of controlled switches (such as IGBT (Insulated Gate Bipolar Transistor)) can also be used.

[0040] After the vehicle voltage conversion controller 140 receives the current rotor position angle of the motor, it selects the corresponding two-phase winding according to the referenced sector correspondence and controls the switches of the switch bridge arms of the two-phase winding. Taking the selection of sector 3 (selecting the A and C phase windings) in Figure 2 as an example, the switches Q3 and Q4 corresponding to the B phase winding can be kept disconnected in Figure 1, and for example, Q1 and Q5 are turned on and Q2 and Q6 are disconnected (or the second output end relative to the charging port is connected to the other pole of the power battery, so that Q1 and Q5 are disconnected and Q2 and Q6 are turned on). In this way, the AC phase switch bridge arm of the motor drive control circuit and the inductance generated by the corresponding winding can be used to form a voltage conversion module (for example, a parallel interleaved Boost booster or Buck buck) to achieve the function of boosting or bucking.

[0041] In some embodiments, the vehicle voltage conversion controller is further configured to distribute the current of the selected two-phase winding according to the rotor position angle, so that during the voltage conversion process, the magnetic flux composed of the two-phase winding does not have a component perpendicular to the direct axis (d axis) of the rotor magnetic flux direction of the motor. Specifically, after the two-phase winding for voltage conversion has been selected, the generation of undesirable torque can be greatly reduced or eliminated. The present application can further determine the current distribution between the selected two-phase windings according to the specific size of the detected current rotor position angle, so that the magnetic flux composed of the two-phase winding does not have a component perpendicular to the direct axis (d axis) of the rotor magnetic flux direction of the motor, and the AC magnetic field (or AC ripple current) is on the q axis to reduce rotor loss, while the DC magnetic field (or DC current) synthesized by the two phases is on the d axis, thereby achieving zero torque output of the motor on the basis of reusing the motor windings for the vehicle boost charging process. In addition, since the AC component in the charging current is the source of the eddy current loss of the motor rotor's magnetic steel during the charging process, and the q-axis inductance of the synchronous motor is small, applying the AC component in the charging current to the q-axis is beneficial to reducing eddy current loss and improving charging efficiency and safety.

[0042] In terms of specific distribution methods, corresponding to the sector division of Figure 2, Figure 4A exemplifies the two-phase winding current distribution adopted by sector 3 (sectors 1 and 5 are similar). At this time, the magnetic field direction of the two AC phases is as follows: AN and Ψ CN As shown by the bold arrows, the direction of the trigonometric function-synthesized magnetic field is concentrated on the direct axis (d axis) and in opposite directions. In addition, Figure 4B shows the two-phase winding current distribution adopted by sector 2 (sectors 2 and 4 are similar). At this time, the magnetic field direction of the two phases AB is as shown by the flux linkage Ψ AN and Ψ BN As shown by the bold arrow, the direction of the magnetic field synthesized by trigonometric functions is concentrated on the direct axis (d axis) and has the same direction.

[0043] In other embodiments, current distribution can also be based on the rotor position angle, such that during voltage conversion, the direct-axis component of the current vector formed by the two-phase windings has a magnitude equal to the magnitude of the flux linkage of the motor's permanent magnets divided by the difference between the motor's direct-axis and quadrature-axis inductances. This allows for efficient current distribution in high-current charging scenarios, achieving zero torque output from the motor.

[0044] In some embodiments, the vehicle voltage conversion controller is further configured to phase-stagger the control signals for the switching actions of the switch arms in the two-phase windings, so that the two switch arms are turned on and off in an alternating manner. For example, as shown in FIG5 , the operating signal waveforms of the switch modules corresponding to the two-phase windings, taking sector 3 of FIG2 or FIG3 as an example, the operating signals of the switch modules (i.e., Q1 and Q5) of the AC two-phase windings are phase-staggered (e.g., 180°, but it is understood that other phase values ​​that can be staggered are also possible). In this way, the eddy current losses of the winding magnetic steel can be significantly reduced, and the impact of input and output ripple can be greatly reduced.

[0045] Figure 6 shows the distribution of current vectors IA(dc), IA(ac), IB(ac), and IB(dc) when the d-axis is 0° and 60°. It can be seen that the AC current vector I∑(ac) of the two-phase windings is concentrated along the q-axis, while the DC current vector I∑(dc) is located along the d-axis. This significantly reduces eddy current losses in the winding magnets and minimizes the impact of input and output ripple.

[0046] According to another aspect of the present application, a vehicle is provided. The vehicle may include a vehicle voltage conversion system or a vehicle voltage conversion controller according to any of the above embodiments. The term "vehicle" as used herein is intended to refer to any suitable vehicle having a drive system, such as a hybrid electric vehicle, an electric vehicle, a plug-in hybrid electric vehicle, and the like.

[0047] FIG7 shows a flow chart of a voltage conversion control method 700 according to one or more embodiments of the present application. The method 700 includes the following steps:

[0048] S1: receiving a detected rotor position angle of a motor of a vehicle. This may be receiving, via a controller, a current rotor position angle of the motor detected by a vehicle motor rotor detection device.

[0049] S2: According to the rotor position angle, by controlling the switching action of the switch bridge arm of the motor drive control circuit, the two-phase winding with a larger inductance value in the three-phase winding of the motor is selected to perform voltage conversion between the vehicle's charging port and the power battery. For example, after the vehicle voltage conversion controller 140 receives the rotor position angle of the motor detected by the vehicle motor rotor detection device, the switching action of the switch bridge arm of the two-phase winding is selected according to the size of the rotor position angle (for example, turning on the control switch of the motor drive control circuit for the two-phase winding and turning off the switch of the other phase) to enable the two switch bridge arms to perform voltage conversion, wherein the switching action includes turning on the switch and turning off the switch. Among them, a schematic diagram of an example corresponding relationship between the rotor position angle and the winding selection is shown in Figure 2.

[0050] Through the above control steps, the vehicle's own motor drive control circuit can be used to perform voltage conversion, so that the external electric energy voltage is suitable for charging the power battery, saving the setting of additional voltage conversion modules / equipment, and the inductance is generated by the winding itself, thereby further reducing the hardware volume and weight of the vehicle control system. More importantly, the vehicle voltage conversion controller in this application only selects two-phase windings and corresponding switching modules to perform electric energy voltage conversion, thus saving the use and loss of one winding. In addition, the sector division and winding selection also take into account the direction of the magnetic field and the motor's cross axis, effectively reducing or eliminating the generation of additional torque and improving the safety of the voltage conversion process.

[0051] Preferably, each switch module of the motor drive control circuit can also be connected in parallel with a diode as shown in Figure 1. That is, each switch bridge arm can include two switch modules connected in series, and each switch module includes a MOS transistor switch and a diode connected in parallel. The vehicle voltage conversion controller 140 is also configured to control the switch control signal of the MOS transistor switch to determine one of the MOS transistor switch and the diode to turn on the switch module. In this way, the control signal of the switch can be determined as needed. For example, in Q1, it is possible to choose to turn on the MOS transistor and turn off the diode, or to choose to turn on the diode and turn off the MOS transistor. The former uses the MOS transistor channel conduction to cause less loss to the circuit.

[0052] After receiving the current rotor position angle of the motor, the corresponding two-phase winding is selected according to the referenced sector correspondence, and the switches of the switch bridge arms of the two-phase winding are controlled. Taking the selection of sector 3 (selecting the A and C phase windings) in Figure 2 as an example, the switches Q3 and Q4 corresponding to the B phase winding can be kept disconnected in Figure 1, and for example, Q1 and Q5 are turned on and Q2 and Q6 are disconnected (or the second output end relative to the charging port is connected to the other pole of the power battery, so that Q1 and Q5 are disconnected and Q2 and Q6 are turned on). In this way, the AC phase switch bridge arm of the motor drive control circuit and the inductance generated by the corresponding winding can be used to form a voltage conversion module (for example, a parallel interleaved Boost booster or Buck buck) to achieve the function of boosting or bucking.

[0053] In some embodiments, the control method can also distribute the current of the selected two-phase winding according to the rotor position angle, so that during the voltage conversion process, the magnetic flux of the two-phase winding does not have a component perpendicular to the direct axis (d-axis) of the motor's rotor magnetic flux. Specifically, after the two-phase winding for voltage conversion has been selected, the generation of undesirable torque can be greatly reduced or eliminated. The present application can further determine the current distribution between the selected two-phase windings according to the specific size of the detected current rotor position angle, so that the magnetic flux of the two-phase winding does not have a component perpendicular to the direct axis (d-axis) of the motor's rotor magnetic flux, and the AC magnetic field (or AC ripple current) is on the q-axis to reduce rotor losses, while the DC magnetic field (or DC current) synthesized by the two phases is on the d-axis, thereby achieving zero torque output of the motor based on the reuse of the motor windings for the vehicle boost charging process. In addition, since the AC component in the charging current is the source of the eddy current loss of the motor rotor's magnetic steel during the charging process, and the q-axis inductance of the synchronous motor is small, applying the AC component in the charging current to the q-axis is beneficial to reducing eddy current losses and improving charging efficiency.

[0054] In other embodiments, the current distribution method in this control method can also be based on the rotor position angle, so that during the voltage conversion process, the direct-axis component of the current vector formed by the two-phase windings has an amplitude equal to the flux linkage of the motor's permanent magnets divided by the difference between the motor's direct-axis and quadrature-axis inductances. This can effectively distribute current in high-current charging scenarios, achieving zero torque output from the motor.

[0055] In some embodiments, the control method further includes staggering the phases of the control signals for the switching actions of the switch bridge arms in the two-phase windings, such as the operating signal waveforms of the selected switching modules corresponding to the two-phase windings shown in FIG5 . This significantly reduces the eddy current losses of the winding magnetic steel and minimizes the impact of input and output ripple.

[0056] According to another aspect of the present application, a computer-readable storage medium is provided, wherein instructions are stored. When the instructions are executed by a processor, the processor is caused to execute any of the voltage conversion control methods 700 described above. The computer-readable medium referred to in the present application includes various types of computer storage media, and can be any available medium that can be accessed by a general-purpose or special-purpose computer. For example, the computer-readable medium can include RAM, ROM, EPROM, E 2PROM, register, hard disk, removable disk, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage device, or any other temporary or non-temporary medium that can be used to carry or store desired program code units in the form of instructions or data structures and can be accessed by a general or special-purpose computer, or a general or special-purpose processor. The above combination should also be included in the protection scope of computer-readable media. Exemplary storage media are coupled to the processor so that the processor can read and write information from / to the storage medium. In an alternative solution, the storage medium can be integrated into the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in a user terminal. In an alternative solution, the processor and storage medium can reside in a user terminal as discrete components.

[0057] According to another aspect of the present application, an electronic device is provided. The electronic device includes a memory and a processor. The memory stores instructions. When the instructions are executed by the processor, the processor executes the voltage conversion control method 700 described above. The memory and the processor can be connected by wire or wirelessly to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses. The memory can be, for example, the above-mentioned computer-readable storage medium. The processor can be a processing module with signal processing capabilities, such as a general-purpose processor, including a central processing unit CPU, a network processor NP, etc.; it can also be a digital signal processor DSP, an application-specific integrated circuit ASIC, a field programmable gate array FPGA or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component.

[0058] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Those skilled in the art can think of other feasible changes or replacements based on the technical scope disclosed in this application, and such changes or replacements are all included in the scope of protection of the present application. In the absence of conflict, the embodiments of the present application and the features in the embodiments can also be combined with each other. The scope of protection of the present application shall be based on the description of the claims.

Claims

1. A vehicle voltage conversion system, characterized in that: The vehicle voltage conversion system includes: Three-phase motor; a motor drive control circuit connected between the vehicle's power battery and the three-phase motor and comprising three switch bridge arms connected in parallel; a charging port, comprising a first output end and a second output end, wherein the first output end is connected to the midpoint of the switch bridge arm corresponding to each winding of the three-phase motor via each winding, and the second output end is connected to one pole of the power battery; and A vehicle voltage conversion controller is configured to select two phase windings with a larger inductance value among the windings of the three-phase motor by controlling the conduction and disconnection of the three switching bridge arms according to the rotor position angle of the three-phase motor, so as to perform voltage conversion between the charging port and the power battery.

2. The vehicle voltage conversion system according to claim 1, characterized in that: The switch bridge arm includes two switch modules connected in series, each of the switch modules includes a MOS tube switch and a diode connected in parallel, and the vehicle voltage conversion controller is further configured to control the switch control signal of the MOS tube switch to determine one of the MOS tube switch and the diode for turning on the switch module.

3. The vehicle voltage conversion system according to claim 1, wherein: The vehicle voltage conversion controller is further configured to distribute the current of the selected two-phase winding according to the rotor position angle, so that during the voltage conversion process, the magnetic flux composed of the two-phase winding does not have a direct axis component perpendicular to the rotor magnetic flux direction of the three-phase motor.

4. The vehicle voltage conversion system according to claim 1, wherein: The vehicle voltage conversion controller is further configured to distribute the current of the selected two-phase winding according to the rotor position angle, so that the direct-axis component of the current vector composed of the two-phase winding during the voltage conversion process is equal in amplitude to the magnetic flux of the permanent magnet of the three-phase motor divided by the amplitude of the difference between the direct-axis and quadrature-axis inductances of the three-phase motor.

5. The vehicle voltage conversion system according to any one of claims 1 to 4, characterized in that: The vehicle voltage conversion controller is further configured to phase-interleave control signals of switches of the switching arms in the two-phase windings.

6. A vehicle voltage conversion controller, characterized in that: The vehicle voltage conversion controller is configured to perform voltage conversion between the charging port of the vehicle and the power battery by selecting two-phase windings with larger inductance values ​​in the windings of the three-phase motor according to the rotor position angle of the vehicle's three-phase motor by controlling the conduction and disconnection of the switch bridge arm of the motor drive control circuit of the three-phase motor. The charging port includes a first output end and a second output end, the first output end is connected to the midpoint of the switch bridge arm corresponding to each winding via each winding of the three-phase motor, and the second output end is connected to one pole of the power battery.

7. A vehicle, characterized in that: The vehicle includes the vehicle voltage conversion system according to any one of claims 1 to 5, or includes the vehicle voltage conversion controller according to claim 6.

8. A vehicle voltage conversion control method, characterized in that: The method comprises the following steps: receiving the detected rotor position angle of the three-phase motor of the vehicle; and According to the rotor position angle, by controlling the conduction and disconnection of the switch bridge arm of the motor drive control circuit of the three-phase motor, two phase windings with a larger inductance value are selected to perform voltage conversion between the charging port of the vehicle and the power battery, The charging port includes a first output terminal and a second output terminal. The output end is connected to the midpoint of the switch bridge arm corresponding to each winding via each winding of the three-phase motor, and the second output end is connected to one pole of the power battery.

9. The voltage conversion control method according to claim 8, characterized in that: The switch bridge arm includes two switch modules connected in series, each of the switch modules includes a MOS tube switch and a diode connected in parallel, and the control of the switch modules of the switch bridge arm further includes: determining one of the MOS tube switch and the diode for turning on the switch module.

10. The voltage conversion control method according to claim 8, wherein: The method further comprises: The currents of the selected two-phase windings are distributed according to the rotor position angle, so that during the transformation process, the flux linkage formed by the two-phase windings does not have a direct axis component perpendicular to the rotor flux linkage direction of the three-phase motor.

11. The voltage conversion control method according to claim 8, wherein: The method further comprises: The current of the selected two-phase winding is distributed according to the rotor position angle, so that during the transformation process, the direct-axis component of the current vector composed of the two-phase winding is equal in amplitude to the magnetic flux of the permanent magnet of the three-phase motor divided by the amplitude of the difference between the direct-axis and quadrature-axis inductances of the three-phase motor.

12. The voltage conversion control method according to any one of claims 8 to 11, characterized in that: The method further comprises: The control signals of the switches of the switching bridge arms in the two-phase winding are phase-staggered.

13. A computer-readable storage medium having instructions stored therein, characterized in that: When the instructions are executed by a processor, the processor is enabled to implement the voltage conversion control method according to any one of claims 8 to 12.

14. An electronic device comprising a memory and a processor, characterized in that: The memory stores instructions, and when the instructions are executed by the processor, the processor is enabled to implement the voltage conversion control method according to any one of claims 8 to 12.

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