Deeply integrated OBC and DCDC system with multiplex electric drive

Abstract

The invention relates to the field of electrical technology, and discloses a multiplex-drive deeply-integrated OBC and DCDC system, which comprises a motor, a switch tube unit, a control unit, an inductor unit and a battery unit, the switch tube unit comprises a plurality of switch tubes and diodes connected in parallel, the battery unit comprises a power battery and a low-voltage storage battery, the inductor unit comprises a first inductor, a second inductor, a third inductor and a fourth inductor, a switch tube unit at the front end of the power battery forms a bridge arm, the bridge arm is a full-control rectifier bridge, the full-control rectifier bridge is used for bidirectional flow of power, the motor is externally connected with a first inductor, and the control unit comprises a switch; the control unit configures the system into a driving mode, an OBC mode, a DCDC mode, a DC charging mode, a boost charging mode, and a buck charging mode. The system has the characteristics of mutual inductance interference resistance, bidirectional power flow and charging matching of a power battery and a low-voltage storage battery in multiple modes.

Description

Technical Field

[0001] The present invention relates to the field of electrical technology, and in particular to a deeply integrated OBC and DCDC system of multiplexed electric drive. Background Art

[0002] With the development of electric vehicles, users have put forward requirements for the charging system of electric vehicles. Traditional electric vehicle charging systems have low integration or have requirements for the form of motors. In recent years, charging technology has made progress, realizing the energy management of electric vehicles and safe control of the charging process, and can charge the batteries of electric vehicles in an efficient way.

[0003] Chinese patent publication number CN113826301B discloses a system and method for charging an electric vehicle, comprising: a motor, the motor comprising a stator, the stator having a plurality of stator teeth and a plurality of stator windings wound on the plurality of stator teeth, wherein the stator winding on at least one stator tooth of the motor is divided into two or more coils; an inverter, the inverter comprising a plurality of power switching devices; an output rectifier; a configurator, the configurator comprising a plurality of contactors coupled to the plurality of stator windings and the plurality of power switching devices; and a controller, the controller being used to control the plurality of power switches The device and the plurality of contactors are configured to configure the system to operate in one of a traction mode and a charging mode, wherein: in the traction mode, the rechargeable battery provides electrical energy to the motor via the inverter; and in the charging mode, the connections associated with the plurality of power switching devices and the stator windings are configured by the configurator to form a charger that draws electrical energy from an external power source to charge the rechargeable battery, and wherein: in the charging mode, the two or more coils on the same stator tooth and the corresponding stator tooth form a transformer in the charger; and In the traction mode, the two or more coils on the same stator tooth are connected in parallel or in series to form a phase winding.

[0004] It can be seen that the system and method for charging electric vehicles have mutual inductance between coils in the charging mode, which causes interference. It is only applicable to concentrated winding motors, not mainstream motors for electric vehicles. In addition, power can only flow from the AC charging port to the battery in one direction. The bridge rectifier at the front end of the battery is an uncontrolled rectifier bridge without an inverter function. Energy can only flow into the battery through the uncontrolled rectifier bridge, but cannot flow from the battery to the uncontrolled rectifier bridge, and external discharge cannot be achieved. Secondly, the charging system does not provide multiple modes for different types of charging piles, and cannot match the charging of power batteries and low-voltage batteries.

[0005] Therefore, how to provide a deeply integrated OBC and DCDC system for multiplexed electric drive is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0006] In view of this, the present invention proposes a deeply integrated OBC and DCDC system for multiplexed electric drive, aiming to solve the mutual inductance interference between motor coils, the power can only flow in one direction, the charging system does not provide multiple modes for different types of charging piles, and cannot match the charging of power batteries and low-voltage batteries.

[0007] The present invention proposes a deeply integrated OBC and DCDC system for multiplexing electric drive, comprising: Motor, switch tube unit, control unit, inductor unit and battery unit; The switch tube unit includes a plurality of switch tubes and diodes matched one to one, and the switch tubes and the diodes are connected in parallel; The battery unit includes: a power battery and a low-voltage storage battery; The inductor unit comprises: a first inductor; The switch tube unit at the front end of the power battery constitutes a bridge arm, the bridge arm is a fully controlled rectifier bridge, the fully controlled rectifier bridge is used for bidirectional power flow, and the motor is externally connected to the first inductor; The control unit comprises: a switch; The control unit configures the system into a driving mode, an OBC mode, a DCDC mode, a DC charging mode, a boost charging mode, and a buck charging mode.

[0008] Furthermore, the deeply integrated OBC and DCDC system of the multiplexed electric drive includes: The switch tube unit includes: a first switch tube module, a second switch tube module, a third switch tube module, a fourth switch tube module, a fifth switch tube module, a sixth switch tube module, a seventh switch tube module, and an eighth switch tube module; The front end of the power battery is connected to the fifth switch tube module and the sixth switch tube module, and the fifth switch tube module and the sixth switch tube module constitute the bridge arm; In the OBC mode, the DC charging mode, the boost charging mode and the buck charging mode, the electromotive force generated by the motor is fed back to the battery unit via the fully controlled rectifier bridge; In the driving mode, the current of the power battery is converted via the fully-controlled rectifier bridge to provide power for the motor.

[0009] Furthermore, the deeply integrated OBC and DCDC system of the multiplexed electric drive includes: In the driving mode, the second switch tube module, the third switch tube module, and the fourth switch tube module constitute a first bridge arm, and the first bridge arm drives a first branch winding of the motor; The first switch tube module, the fifth switch tube module and the sixth switch tube module constitute a second bridge arm, and the second bridge arm drives the second branch winding of the motor.

[0010] Furthermore, the deeply integrated OBC and DCDC system of the multiplexed electric drive includes: In the OBC mode, the OBC circuit is divided into a PFC circuit and an LLC circuit. The PFC circuit corrects the power factor of the AC pile and rectifies the AC power into DC power and outputs it to the LLC circuit. The PFC circuit includes: the AC pile, the first switch tube module and the second switch tube module; The LLC circuit includes: the third switch tube module, the fourth switch tube module, the fifth switch tube module, the sixth switch tube module, and windings U1, U2 and V2 of the motor; The LLC circuit resonantly converts the direct current to charge the power battery.

[0011] Furthermore, the deeply integrated OBC and DCDC system of the multiplexed electric drive includes: In the DCDC mode, the winding of the motor is the first winding, the power winding of the first winding is W2, the first winding constitutes a first isolation transformer, and the AC pile charges the low-voltage battery via the first isolation transformer; The seventh switch tube module and the eighth switch tube module constitute a rectifier, and the rectifier is used to rectify the AC pile.

[0012] Furthermore, the deeply integrated OBC and DCDC system of the multiplexed electric drive includes: In the boost charging mode, the voltage of the DC pile is inverted into an AC voltage; The winding of the motor is a second winding, the second winding constitutes a second isolation transformer, and the AC voltage is boosted by the second isolation transformer to charge the power battery; The winding U1 of the motor is connected in series with a capacitor block and the first inductor, so as to boost the AC voltage to a first AC voltage, and the second isolation transformer boosts the first AC voltage.

[0013] Furthermore, the deeply integrated OBC and DCDC system of the multiplexed electric drive includes: In the step-down charging mode, the winding of the motor is a third winding, the third winding constitutes a third isolation transformer, and the AC voltage is rectified by the third isolation transformer to charge the power battery.

[0014] Furthermore, in the DC charging mode, the voltage of the DC pile is directly output to the power battery.

[0015] Furthermore, the power taking winding is W1 or the left section of W2 or the right section of W2.

[0016] Furthermore, the winding of the motor is in star mode or triangle mode.

[0017] Compared with the prior art, the beneficial effects of the present invention are: the reuse of motors, inductors and switch tubes reduces the redundant components in the system, reduces the weight of the system, reduces the cost, and improves the compactness of the system compared to the traditional OBC and DCDC integrated system. Through the configuration of the control unit, the system can switch between the driving mode, OBC mode, DCDC mode, DC charging mode, boost charging mode and buck charging mode, realize flexible adjustment of charging, and improve the utilization rate of electric energy. The system has boost and buck charging modes, which can adjust the voltage according to different power supply conditions, enhance the system's compatibility with various types of charging piles, and the power flows in both directions, which improves the system's management of electric energy, optimizes the charging and discharging process, and reduces the current fluctuation of the system. The control unit controls the working state of the switch tube unit, thereby effectively protecting the power battery and the low-voltage battery from the risk of overcurrent and overvoltage, and improving the safety and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1 A schematic diagram of the structure of a deeply integrated OBC and DCDC system for multiplexed electric drive provided in an embodiment of the present invention; Figure 2 A schematic diagram of a driving mode provided by an embodiment of the present invention; Figure 3 A schematic diagram of the structure of the OBC mode & DCDC mode provided in an embodiment of the present invention; Figure 4 A schematic diagram of the structure of a boost charging mode provided by an embodiment of the present invention; Figure 5 A schematic diagram of a buck charging mode provided in an embodiment of the present invention; Figure 6 A schematic diagram of the structure of a DC charging mode provided in an embodiment of the present invention; Figure 7 A schematic diagram of the structure of the power taking winding W1 provided in an embodiment of the present invention; Figure 8 The power taking winding provided in the embodiment of the present invention is a schematic diagram of the structure of the left section of W2; Fig. 9 The power taking winding provided in the embodiment of the present invention is a schematic diagram of the structure of the right section of W2; Fig.10 A schematic structural diagram of a triangle mode provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0020] See also Figure 1 As shown, in some embodiments of the present application, this embodiment provides a deeply integrated OBC and DCDC system for multiplexed electric drive, including: a motor, a switch tube unit, a control unit, an inductor unit and a battery unit, the switch tube unit includes a number of one-to-one matched switch tubes and diodes, the switch tube and the diode are connected in parallel, the battery unit includes: a power battery BT1 and a low-voltage battery BT2, the inductor unit includes: a first inductor Lr1, the switch tube unit at the front end of the power battery BT1 constitutes a bridge arm, the bridge arm is a fully controlled rectifier bridge, the fully controlled rectifier bridge is used for bidirectional power flow, the motor is externally connected to the first inductor Lr1, the control unit includes: a switch, the control unit configures the system to a drive mode, an OBC mode, a DCDC mode, a DC charging mode, a boost charging mode and a buck charging mode.

[0021] Specifically, the motor can be a six-phase motor with six windings, or a three-phase motor that can be split into two parallel branches. Compared with concentrated winding motors, six-phase motors and three-phase motors with parallel branches reduce the spatial harmonic content, reduce the vibration and noise of the motor, and improve the stability of the motor. Six-phase motors and three-phase motors with parallel branches can form a uniform air gap magnetic field, reduce motor torque pulsation, and improve the efficiency and reliability of the motor. The deeply integrated OBC and DCDC system of the multiplexed electric drive meets the mainstream motors of new energy vehicles. The switch tube unit is composed of multiple switch tubes and parallel diodes to achieve flexible control of power transmission in different working modes of the system. The switch tube unit is configured at the front end of the power battery BT1 to form a bridge arm circuit. The control unit transmits power to the motor by modulating the on and off state of the switch through pulse width modulation. The switches include: K1, K2, K3, K4, K5, K6, K7, K8, K9, K10 and K11. The parallel diode provides a freewheeling path for electric energy to prevent current interruption and ensure a smooth transition of the motor winding current. When the motor's mechanical energy is converted into electrical energy, the generated power is fed back to the battery unit through a fully controlled rectifier bridge to achieve energy feedback. The control unit is responsible for managing the working status of the switch tube unit and the inductor unit, and switching the system to multiple working modes. The OBC mode is for the external AC pile to flow to the power battery BT1 to achieve on-board charging. The DCDC mode controls the conversion of high-voltage electricity from the power battery BT1 to the low-voltage battery BT2 to achieve on-board low-voltage system power supply. The DC charging mode is for the DC pile to directly charge the power battery BT1. The boost charging mode uses the inductor unit to increase the charging voltage and charge the high-voltage platform power battery BT1. The buck charging mode reduces the charging voltage and charges the low-voltage platform power battery BT1, while giving full play to the maximum charging capacity of the charging pile.

[0022] It is understandable that the power battery BT1 provides driving power for the motor and supports energy storage in the OBC mode, and the low-voltage battery BT2 powers the low-voltage devices on the vehicle, such as lighting and the in-vehicle infotainment system. By reusing the motor windings and the first inductor Lr1, it avoids configuring independent electrical components for the OBC and DCDC modes, saving costs and space, and achieving the requirements for battery charging. The operation of the fully controlled rectifier bridge and the control unit enables the system to efficiently complete energy transfer and conversion in multiple modes.

[0023] In some embodiments of the present application, the switch tube unit includes: a first switch tube module, a second switch tube module, a third switch tube module, a fourth switch tube module, a fifth switch tube module, a sixth switch tube module, a seventh switch tube module, and an eighth switch tube module. The front end of the power battery BT1 is connected to the fifth switch tube module and the sixth switch tube module. The fifth switch tube module and the sixth switch tube module constitute a bridge arm. In OBC mode, DC charging mode, boost charging mode and buck charging mode, the electromotive force generated by the motor is fed back to the battery unit via a fully-controlled rectifier bridge. In driving mode, the current of the power battery BT1 is converted via the fully-controlled rectifier bridge to provide power for the motor.

[0024] Specifically, the first switch tube module includes: S1 and a diode in parallel, S2 and a diode in parallel, the second switch tube module includes: S3 and a diode in parallel, S4 and a diode in parallel, the third switch tube module includes: S5 switch tube and a diode in parallel, S6 and a diode in parallel, the fourth switch tube module includes: S7 switch tube and a diode in parallel, S8 and a diode in parallel, the fifth switch tube module includes: S9 switch tube and a diode in parallel, S10 and a diode in parallel, the sixth switch tube module includes: S11 switch tube and a diode in parallel, S12 and a diode in parallel, the seventh switch tube module includes: S13 switch tube and a diode in parallel, S14 and a diode in parallel, the eighth switch tube module includes: S15 switch tube and a diode in parallel, S16 and a diode in parallel, and S9, S10, S11, S12 and a diode in parallel at the front end of the power battery BT1 constitute a bridge arm.

[0025] It can be understood that the operation of the motor will generate an electromotive force, which is rectified through a fully-controlled rectifier bridge, and its power is fed back to the battery unit. The fully-controlled rectifier bridge will output the current through capacitor C2 to stably charge the power battery BT1.

[0026] See also Figure 2 As shown, in some embodiments of the present application, a deeply integrated OBC and DCDC system of multiplexed electric drive includes: in a driving mode, the second switch tube module, the third switch tube module, and the fourth switch tube module constitute a first bridge arm, and the first bridge arm drives the first branch winding of the motor; the first switch tube module, the fifth switch tube module, and the sixth switch tube module constitute a second bridge arm, and the second bridge arm drives the second branch winding of the motor.

[0027] It can be understood that in the driving mode, K1, K2, K3, K4, K5 and K6 are closed, and other switches are disconnected. S3, S4, S5, S6, S7 and S8 and the parallel diodes constitute the first bridge arm, which constitutes the first branch winding U1, V1 and W1 of the drive motor. S1, S2, S9, S10, S11 and S12 and the parallel diodes constitute the second bridge arm, which constitutes the second branch winding U2, V2 and W2 of the drive motor. The power battery BT1 is connected to the capacitor C1 and the capacitor C2. C1 and C2 are intended to stabilize the voltage of the power battery BT1, reduce noise, and protect the power battery BT1 and the system circuit from instantaneous load changes. C1 reduces the voltage fluctuation caused by load changes and absorbs instantaneous charge, thereby stabilizing the voltage of the power battery BT1. C2 is used to filter out high-frequency noise and interference, weaken high-frequency electromagnetic interference and radio frequency interference, and absorb high-frequency harmonics and interference signals in the power battery BT1, thereby improving the reliability of the power battery BT1 for motor driving.

[0028] See also Figure 3 As shown, in some embodiments of the present application, a deeply integrated OBC and DCDC system of multiplexed electric drive includes: in OBC mode, the OBC circuit is divided into a PFC circuit and an LLC circuit, the PFC circuit corrects the power factor of the AC pile and rectifies the AC power into DC power and outputs it to the LLC circuit, the PFC circuit includes: an AC pile, a first switch tube module and a second switch tube module, the LLC circuit includes: a third switch tube module, a fourth switch tube module, a fifth switch tube module, a sixth switch tube module, and motor windings U1, U2 and V2, and the LLC circuit converts DC power into resonance to charge the power battery BT1.

[0029] Specifically, in the OBC mode, the fourth switch tube module and the fifth switch tube module connect the capacitor block Cr1 and the first inductor Lr1, K1, K2, K7, K10 and K11 are closed, and other switches are disconnected. The PFC circuit is composed of an AC pile, S1, S2, S3 and S4 and parallel diodes, and the LLC circuit is composed of S5, S6, S7, S8, S9, S10, S11 and S12 and parallel diodes, and the motor windings U1, U2 and V2. The PFC circuit rectifies the AC power of the AC pile through S1, S2, S3 and S4 and parallel diodes, so that the input current is synchronized with the input voltage waveform phase to ensure that the power factor is close to 1, so that the AC power is rectified into DC power. The PFC circuit improves the utilization rate of electric energy and reduces harmonic pollution.

[0030] It is understandable that in the LLC circuit, the capacitor block Cr1 and the first inductor Lr1 form a resonant circuit so that the operating frequency matches the natural resonant frequency of the LC circuit. The LLC circuit adjusts the operating frequency to make the circuit operate at different resonant points to match the charging voltage, power and other requirements of the power battery BT1.

[0031] In some embodiments of the present application, a deeply integrated OBC and DCDC system for multiplexing electric drive includes: in DCDC mode, the winding of the motor is the first winding, the power taking winding of the first winding is W2, the first winding constitutes a first isolation transformer, the AC pile charges the low-voltage battery BT2 via the first isolation transformer, the seventh switch tube module and the eighth switch tube module constitute a rectifier, and the rectifier is used to rectify the AC pile.

[0032] Specifically, in the DCDC mode, the inductor unit is also provided with a second inductor Lr2. The winding U1 of the motor is connected in series with U2, V2 and W2 to form three sets of mutually coupled windings, and the three sets of mutually coupled windings constitute the first winding. The power winding W2 is powered by the first isolation transformer. The rectifier is composed of S13, S14, S15 and S16 and parallel diodes. The power is transmitted to the rectifier. The rectifier converts the AC power with large fluctuations of the power battery BT1 into smooth DC power, providing stable power supply for the subsequent charging of the low-voltage battery BT2. The rectifier is connected to the Buck circuit, which is composed of capacitors C3, S17, the first diode D1, the second inductor Lr2 and the capacitor C4. The switch tube S17 controls the on and off of the Buck circuit. The first diode D1 provides a freewheeling path. The second inductor Lr2 divides the voltage, stores and releases energy. The capacitor C4 stabilizes and filters the voltage to complete the voltage reduction of the DC power and ensure the stability of the voltage output to the low-voltage battery BT2.

[0033] It can be understood that the OBC mode can be used alone, and the OBC mode and DCDC mode can also be used at the same time. When the OBC mode is used alone, K10 and K11 are disconnected to turn off the DCDC mode. When the DCDC mode is used alone, K10 and K11 are closed and the other switches are disconnected to draw power from the power battery BT1.

[0034] See also Figure 4 As shown, in some embodiments of the present application, a deeply integrated OBC and DCDC system for multiplexing electric drive includes: in boost charging mode, the voltage of the DC pile is inverted into AC voltage, the winding of the motor is the second winding, the second winding constitutes a second isolation transformer, and the AC voltage is boosted by the second isolation transformer to charge the power battery BT1, the winding U1 of the motor is connected in series with the capacitor block Cr1 and the first inductor Lr1, which is used to boost the AC voltage to the first AC voltage, and the second isolation transformer boosts the first AC voltage.

[0035] Specifically, when the voltage of the DC pile is lower than the voltage of the power battery BT1, the output voltage of the DC pile needs to be boosted before the power battery BT1 can be charged. When the charging voltage of the DC pile is lower than the voltage of the power battery BT1, K7 is closed, and the other switches are disconnected to enter the boost charging mode. The second winding is composed of U1, U2 and V2. The DC voltage is first filtered by capacitor C1 and inverted into AC voltage by S5, S6, S7 and S8 and parallel diodes. The motor winding U1 is connected in series with capacitor block Cr1 and the first inductor Lr1. The AC voltage is boosted to the first AC voltage through inverter oscillation. The transformation ratio of the second isolation transformer is greater than 1. The second isolation transformer boosts the first AC voltage, and the boosted electric energy is transmitted to the power battery BT1. The boost charging mode can be used alone, and the boost charging mode and DCDC mode can also be used at the same time. The method of turning on the DCDC mode has been described above and will not be described here.

[0036] It is understandable that when the voltage of the DC pile increases, the stability of the power battery BT1 during the charging process is improved. Different models of power batteries BT1 have different charging voltage requirements. The boost charging mode can adjust the output voltage according to the charging requirements of the power battery BT1, so that the charging pile can support power batteries BT1 with different voltage specifications, thereby improving the compatibility and flexibility of the system and reducing charging failures caused by voltage instability or mismatch.

[0037] See also Figure 5 As shown, in some embodiments of the present application, a deeply integrated OBC and DCDC system of multiplexed electric drive includes: in the step-down charging mode, the winding of the motor is the third winding, the third winding constitutes the third isolation transformer, and the AC voltage is rectified by the third isolation transformer to charge the power battery BT1.

[0038] Specifically, when the high-voltage DC pile directly charges the low-voltage platform power battery BT1, the charging power of the DC pile cannot be brought into play. For example, when the charging voltage is 800V and the peak current is 200A, the peak charging power is 160kW. If the charging pile is used to directly charge a 400V battery, the output voltage of the DC pile needs to be close to 400V, and the charging power is only 80kW. When the DC pile is charging, if the output voltage of the DC pile is higher than the voltage of the power battery BT1 and the power battery BT1 can withstand the charging power of the DC pile, K8 is closed, the remaining switches are disconnected, and the system starts the step-down charging mode.

[0039] Specifically, the third winding is composed of U1, U2 and V2. S5, S6, S7 and S8 and the parallel diodes invert the voltage of the DC pile into AC voltage. The AC voltage is adjusted by the duty cycle of the third isolation transformer, and then rectified into DC voltage by S9, S10, S11 and S12 and the parallel diodes. The converted DC voltage charges the low-voltage platform power battery BT1. The flexibility and compatibility of the system are improved.

[0040] See also Figure 6 As shown, in some embodiments of the present application, in the DC charging mode, the voltage of the DC pile is directly output to the power battery BT1.

[0041] It can be understood that when the voltage of the DC pile matches that of the power battery BT1, K5 and K6 are closed, the remaining switches are disconnected, the DC charging mode is turned on, the first bridge arm and the second bridge arm both stop working, and the output voltage of the DC pile is directly output to the power battery BT1 to charge the power battery BT1, making it convenient for the DC pile to charge quickly.

[0042] See also Figure 7-9 As shown, in some embodiments of the present application, the power winding is the left section of W1 or W2 or the right section of W2.

[0043] It can be understood that when the power winding is W1, the startup of each mode of the system is the same as above and will not be elaborated here. When the power winding is the left section of W1 or W2 or the right section of W2, the number of turns of the motor winding coil is extended, the transformation ratio step-down is increased, and the flexibility of high-voltage DC inverter to low-voltage AC is improved.

[0044] See also Fig.10 As shown, in some embodiments of the present application, the winding of the motor is in star mode or triangle mode.

[0045] Specifically, the motor winding is in star mode, and the system can convert the star mode to triangle mode. Compared with the star mode, the triangle mode adds two switches K12 and K13. In triangle mode, when the driving mode is turned on, switches K1, K2, K3, K4, K5, K6, K8, K9, K12 and K13 are closed, and the other switches are disconnected. When the OBC&DCDC mode is turned on, switches K1, K2, K7, K10 and K11 are closed, and the other switches are disconnected. When the DC charging mode is turned on, switches K5 and K6 are closed, and the other switches are disconnected. When the boost charging mode is turned on, switch K7 is closed, and the other switches are disconnected. When the buck charging mode is turned on, switch K12 is closed, and the other switches are disconnected.

[0046] It is understandable that the motor winding conversion mode improves the flexibility of the system, helps the system get rid of the requirements of the motor winding form, and improves the system's compatibility with the motor.

[0047] In summary, the beneficial effects of the present invention are: the reuse of motors, inductors and switch tubes reduces redundant components in the system, reduces the weight of the system, reduces costs, and improves the compactness of the system compared to traditional OBC and DCDC integrated systems. Through the configuration of the control unit, the system can switch between drive mode, OBC mode, DCDC mode, DC charging mode, boost charging mode and buck charging mode, thereby achieving flexible adjustment of charging and improving the utilization rate of electric energy. The system has boost and buck charging modes, which can adjust the voltage according to different power supply conditions, enhance the system's compatibility with various types of charging piles, and bidirectional power flow, thereby improving the system's management of electric energy, optimizing the charging and discharging process, and reducing the current fluctuation of the system. The control unit controls the working state of the switch tube unit, thereby effectively protecting the power battery and low-voltage battery from the risks of overcurrent and overvoltage, and improving the safety and reliability of the system.

[0048] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0049] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0050] These computer program instructions may also be stored in a computer-readable storage device that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable storage device produce a product including an instruction device that implements the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0051] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A deeply integrated OBC and DCDC system with multiplexed electric drive, characterized in that: include: Motor, switch tube unit, control unit, inductor unit and battery unit; The switch tube unit includes a plurality of switch tubes and diodes matched one to one, and the switch tubes and the diodes are connected in parallel; The battery unit includes: a power battery and a low-voltage storage battery; The inductor unit comprises: a first inductor; The switch tube unit at the front end of the power battery constitutes a bridge arm, the bridge arm is a fully controlled rectifier bridge, the fully controlled rectifier bridge is used for bidirectional power flow, and the motor is externally connected to the first inductor; The control unit comprises: a switch; The control unit configures the system into a driving mode, an OBC mode, a DCDC mode, a DC charging mode, a boost charging mode, and a buck charging mode.

2. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 1, characterized in that: include: The switch tube unit includes: a first switch tube module, a second switch tube module, a third switch tube module, a fourth switch tube module, a fifth switch tube module, a sixth switch tube module, a seventh switch tube module, and an eighth switch tube module; The front end of the power battery is connected to the fifth switch tube module and the sixth switch tube module, and the fifth switch tube module and the sixth switch tube module constitute the bridge arm; In the OBC mode, the DC charging mode, the boost charging mode and the buck charging mode, the electromotive force generated by the motor is fed back to the battery unit via the fully controlled rectifier bridge; In the driving mode, the current of the power battery is converted via the fully-controlled rectifier bridge to provide power for the motor.

3. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 2, characterized in that: include: In the driving mode, the second switch tube module, the third switch tube module, and the fourth switch tube module constitute a first bridge arm, and the first bridge arm drives a first branch winding of the motor; The first switch tube module, the fifth switch tube module and the sixth switch tube module constitute a second bridge arm, and the second bridge arm drives the second branch winding of the motor.

4. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 2, characterized in that: include: In the OBC mode, the OBC circuit is divided into a PFC circuit and an LLC circuit. The PFC circuit corrects the power factor of the AC pile and rectifies the AC power into DC power and outputs it to the LLC circuit. The PFC circuit includes: the AC pile, the first switch tube module and the second switch tube module; The LLC circuit includes: the third switch tube module, the fourth switch tube module, the fifth switch tube module, the sixth switch tube module, and windings U1, U2 and V2 of the motor; The LLC circuit resonantly converts the direct current to charge the power battery.

5. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 4, characterized in that: include: In the DCDC mode, the winding of the motor is the first winding, the power winding of the first winding is W2, the first winding constitutes a first isolation transformer, and the AC pile charges the low-voltage battery via the first isolation transformer; The seventh switch tube module and the eighth switch tube module constitute a rectifier, and the rectifier is used to rectify the AC pile.

6. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 2, characterized in that: include: In the boost charging mode, the voltage of the DC pile is inverted into an AC voltage; The winding of the motor is a second winding, the second winding constitutes a second isolation transformer, and the AC voltage is boosted by the second isolation transformer to charge the power battery; The winding U1 of the motor is connected in series with a capacitor block and the first inductor, so as to boost the AC voltage to a first AC voltage, and the second isolation transformer boosts the first AC voltage.

7. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 6, characterized in that: include: In the step-down charging mode, the winding of the motor is a third winding, the third winding constitutes a third isolation transformer, and the AC voltage is rectified by the third isolation transformer to charge the power battery.

8. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 7, characterized in that: In the DC charging mode, the voltage of the DC pile is directly output to the power battery.

9. The deeply integrated OBC and DCDC system of multiplexed electric drive according to claim 5, characterized in that: The power taking winding is W1 or the left section of W2 or the right section of W2.

10. The deeply integrated OBC and DCDC system of multiplexed electric drive according to any one of claims 1 to 9, characterized in that: The winding of the motor is in star mode or delta mode.

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