Vehicle-mounted electric energy management system

Abstract

The invention discloses a vehicle-mounted electric energy management system. Comprising a first power switch device, a second power switch device, a third power switch device, a fourth power switch device, a fifth power switch device, a sixth power switch device, a first voltage sensor, a first current sensor, a second current sensor, a filter capacitor, a first switch, a second switch, an EMI filter, a first inductor, a second inductor and a third inductor. The system comprises a VCU, a high-voltage direct-current bus interface, a three-phase motor interface and an external power supply interface. The system is used for mutual conversion between alternating current and direct current of a power supply system of the electric vehicle, and bidirectional direct current-direct current conversion, single-phase alternating current-direct current conversion, single-phase direct current-alternating current conversion, three-phase alternating current-direct current conversion and three-phase direct current-alternating current conversion between power supplies can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle energy, and particularly relates to a vehicle electric energy management system. Background Art

[0002] At present, with the popularization of electric vehicles and hybrid vehicles, the demand for vehicle electric energy management systems is becoming increasingly urgent. Traditional vehicle electric energy management systems usually consist of a single energy conversion mode, such as a three-phase motor controller or a DC-AC inverter. These systems have some problems in energy conversion and management, such as low energy utilization rate and single function. Some household small charging piles require a charger with single-phase AC / DC function, and some commercial high-power charging piles use three-phase electricity, so they need a charger with three-phase AC / DC function. At the same time, some new energy vehicles have the need for DC fast charging input or DC output, and a bidirectional DC / DC converter is required for the conversion of bidirectional DC power. In addition, when carrying out outdoor activities, in order to meet the needs of three-phase and single-phase AC electrical equipment, a three-phase DC / AC inverter and a single-phase DC / AC inverter are respectively required to convert the battery DC power into AC power. At the same time, electric vehicles need to control the motor, and also need a three-phase DC / AC inverter. Currently, in order to achieve these six functions, it is necessary to equip a bidirectional DC / DC converter, two three-phase AC / DC chargers, a single-phase AC / DC charger, a three-phase DC / AC inverter, and a single-phase DC / AC inverter, which occupies valuable space in the vehicle, increases the weight and cost of the electric vehicle.

[0003] An existing integrated multi-functional power conversion system (CN105871205A) is used for the mutual conversion between AC and DC of an electric vehicle power system, and can realize bidirectional DC-DC conversion, single-phase AC-DC conversion, and DC-single-phase AC conversion between power sources. This system can only achieve bidirectional DC / DC, single-phase AC / DC, and single-phase DC / AC functions, and cannot handle three-phase power and control the motor. A three-port full-bridge inverter and its control method (CN201210148917.7) relates to a three-port full-bridge inverter and its control method, which can simultaneously realize power management and control of an AC load, a storage battery, and an input source, and integrates two DC input terminals and one AC output terminal. However, this invention can only achieve single-phase DC / AC inversion and bidirectional DC / DC conversion functions. In addition, with the development and application of new energy technologies, such as photovoltaic cells and fuel cells, traditional vehicle electric energy management systems can no longer meet the requirements of efficient utilization and flexible conversion of multiple energy sources. Therefore, there is an urgent need for a vehicle electric energy management system that can integrate multiple energy conversion modes and achieve efficient energy management. Summary of the Invention

[0004] The object of the present invention is to provide an integrated vehicle multi-functional power management system. The three-phase AC / DC converter, three-phase DC / AC converter, single-phase AC / DC converter, single-phase DC / AC converter, and bidirectional DC / DC converter share controllable power switching devices, reducing the number of power switching devices and the number of radiators supporting them, having a smaller volume, lighter weight, and lower cost, and achieving the efficient utilization and flexible conversion of various energy sources.

[0005] Optionally, the vehicle power management system further includes a vehicle control unit (VCU). By digitally controlling the power switching devices through the VCU, the system can operate in five modes: three-phase AC / DC conversion, three-phase DC / AC conversion, single-phase AC / DC conversion, single-phase DC / AC conversion, and bidirectional DC / DC conversion. Adjust the working mode and parameters of the system according to the actual energy demand and conditions, and integrate and control the energy flow to achieve the efficient utilization of energy and the stable operation of the system.

[0006] The present invention is achieved by at least one of the following technical solutions.

[0007] A vehicle power management system includes: a first power switching device, a second power switching device, a third power switching device, a fourth power switching device, a fifth power switching device, a sixth power switching device, a first voltage sensor, a first current sensor, a second current sensor, a filter capacitor, a first switch, a second switch, an EMI filter, a first inductor, a second inductor, a third inductor; a VCU, a high-voltage DC bus interface, a three-phase motor interface, an external power supply interface;

[0008] The emitter of the first power switching device is connected to the collector of the second power switching device to form a first set of bridge arms. The collector terminal of the first power switching device is the high end of the bridge arm, the connection between the emitter of the first power switching device and the collector of the second power switching device is the midpoint of the bridge arm, the emitter of the second power switching device is the low end of the bridge arm, and the emitter of the second power switching device is connected to the negative pole of the high-voltage DC bus interface; The emitter of the third power switching device is connected to the collector of the fourth power switching device to form a second set of bridge arms. The collector of the third power switching device is the high end of the bridge arm, the connection between the emitter of the third power switching device and the collector of the fourth power switching device is the midpoint of the bridge arm, the emitter of the fourth power switching device is the low end of the bridge arm, and the emitter of the fourth power switching device is connected to the negative pole of the high-voltage DC bus interface; The emitter of the fifth power switching device is connected to the collector of the sixth power switching device to form a third set of bridge arms. The collector of the fifth power switching device is the high end of the bridge arm, the connection between the emitter of the fifth power switching device and the collector of the sixth power switching device is the midpoint of the bridge arm, the emitter of the sixth power switching device is the low end of the bridge arm, and the emitter of the sixth power switching device is connected to the negative pole of the high-voltage DC bus interface;

[0009] The common terminal of the first switch is connected to the midpoints of the first, second, and third groups of bridge arms through the second current sensor respectively; the first voltage sensor is connected between the positive and negative poles of the high-voltage DC bus interface, both ends of the first current sensor are connected to the positive pole of the high-voltage DC bus and the positive pole of the filter capacitor, and the negative pole of the filter capacitor is connected to the negative pole of the high-voltage DC bus interface;

[0010] The high and low ends of the three bridge arms composed of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device are connected respectively. The high and low ends of the three bridge arms are connected to the positive and negative poles of the filter capacitor respectively and then connected to the positive and negative poles of the high-voltage DC bus interface;

[0011] The positive and negative poles of the high-voltage battery pack are connected to the positive and negative poles of the high-voltage DC bus interface respectively; the external power interface is connected to the first inductor, the second inductor, and the third inductor through the EMI filter. The other ends of the first inductor and the second inductor are both connected to the second output terminal of the first switch. The other end of the third inductor is connected to the second switch, the other end of the second switch is connected to the second output terminal of the first switch, and the first output terminal of the first switch is connected to the three-phase motor interface;

[0012] The first voltage sensor, the first current sensor, the second current sensor, the first switch, and the second switch are all connected to the VCU respectively. After the current sensor and the voltage sensor sample the voltage and current signals, they are sent to the VCU. After calculation, the VCU generates PWM signals to control the on and off of the power switch devices to meet the requirements of different conversion modes.

[0013] Further, the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device are metal-oxide semiconductor field-effect transistors, intelligent power modules, or insulated gate bipolar transistors with a switch tube and a reverse-parallel diode integrated inside. The cathode of the reverse-parallel diode is connected to the collector of the switch tube, and the anode of the reverse-parallel diode is connected to the emitter of the switch tube.

[0014] Further, the power of the high-voltage DC bus interface is converted to the external power interface or the three-phase motor through the power switch device to provide three-phase, single-phase alternating current and direct current. The power of the external power interface or the three-phase motor is reversely converted to the high-voltage DC bus interface through the power switch device to provide direct current, realizing bidirectional energy flow.

[0015] Further, the high-voltage DC bus interface serves as a DC output interface in the three-phase AC / DC mode, converting three-phase alternating current into direct current and transmitting it to the high-voltage battery pack. In the three-phase DC / AC mode, it serves as a DC input interface, transmitting the energy of the high-voltage battery pack to the subsequent stage to provide three-phase alternating current. The high-voltage DC bus interface serves as a DC output interface in the single-phase AC / DC mode, converting single-phase alternating current into direct current and transmitting it to the high-voltage battery pack. In the single-phase DC / AC mode, it serves as a DC input interface, transmitting the energy of the high-voltage battery pack to the subsequent stage to provide single-phase alternating current. In the bidirectional DC / DC mode, it forms a two-phase interleaved structure to reduce current and voltage ripples.

[0016] Further, the first output terminal of the first switch is closed, and the first switch is connected to the three-phase motor interface. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase full-bridge inverter. The VCU uses space vector pulse width modulation (SVPWM) to generate six PWM signals, which are respectively sent to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device. The energy directly flows from the high-voltage battery pack to the three-phase motor connected to the first switch, achieving precise control of the motor.

[0017] Further, the second output terminal of the first switch is closed, and the second switch is normally closed. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase DC / AC inverter, converting the DC power supply of the high-voltage battery pack into three-phase alternating current required by the local load or the power grid on the external power interface. The VCU generates six PWM signals, which are respectively sent to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device.

[0018] Further, the second output terminal of the first switch is closed, and the second switch is normally closed. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase AC / DC rectifier, converting the three-phase alternating current on the external power interface into the DC power supply of the high-voltage battery pack. The VCU generates six PWM signals, which are respectively sent to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device.

[0019] Further, the second output terminal of the first switch is closed, and the second switch is opened. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase DC / AC inverter, which converts the DC power supply of the high-voltage battery pack into single-phase alternating current required by the local load on the external power supply interface. The VCU generates six PWM signals and sends them to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device respectively.

[0020] Further, the second output terminal of the first switch is closed, and the second switch is opened. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a single-phase AC / DC rectifier, which converts the single-phase alternating current on the external power supply interface into the DC power supply of the high-voltage battery pack. The VCU generates six PWM signals and sends them to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device respectively.

[0021] Further, the second output terminal of the first switch is closed, and the second switch is opened. The third power switch device, the fourth power switch device, the fifth power switch device, the sixth power switch device, the first inductor, the second inductor, and the filter capacitor form a bidirectional DC / DC circuit to realize the bidirectional flow of DC power. The VCU generates [number of] PWM signals and sends them to the gates of the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device respectively.

[0022] Compared with the existing technologies, the beneficial effects of the present invention are as follows:

[0023] (1) The bidirectional DC / DC, three-phase AC / DC, three-phase DC / AC, single-phase AC / DC, and single-phase DC / AC five modes share power switch devices, sensors, drivers, and controllers, reducing the system volume and saving the system cost.

[0024] (2) In the single-phase AC / DC mode, four fully controllable power switch devices are used to form an H-bridge, which can achieve power factor correction.

[0025] (3) It adopts a three-phase AC-DC architecture. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device and the sixth power switch device form 3 half-bridges. Using two switches, three inductors and an EMI filter to integrate five modes of bidirectional DC / DC, three-phase AC / DC, three-phase DC / AC, single-phase AC / DC and single-phase DC / AC, it can realize multiple functions such as motor control, three-phase charging and single-phase charging of the battery pack, and three-phase and single-phase inverters. Description of the Drawings

[0026] Figure 1 It is the schematic diagram of the in-vehicle power management system according to the embodiment of the present invention;

[0027] Figure 2 It is the equivalent circuit schematic diagram of the motor control according to the embodiment of the present invention;

[0028] Figure 3 It is the equivalent circuit schematic diagram of the three-phase AC / DC and three-phase DC / AC according to the embodiment of the present invention;

[0029] Figure 4 It is the equivalent circuit schematic diagram of the single-phase DC / AC and single-phase AC / DC according to the embodiment of the present invention;

[0030] Figure 5 It is the equivalent circuit schematic diagram of the bidirectional DC / DC according to the embodiment of the present invention. Detailed Embodiment

[0031] To better understand the present invention, the following further illustrates the present invention in conjunction with the drawings and embodiments, but the embodiments of the present invention are not limited thereto.

[0032] The in-vehicle power management system of the present invention is applied to the composite power system of new energy vehicles. The in-vehicle power management system performs power conversion between the high-voltage battery pack and the external load, converts the three-phase AC or single-phase AC input power into DC power to charge the high-voltage battery pack, and converts the DC power of the high-voltage battery pack into three-phase AC output, single-phase AC output or DC output.

[0033] As Figure 1 shown, the in-vehicle power management system of this embodiment includes a VCU1, a high-voltage DC bus interface 21, an external power interface 22, a first voltage sensor 31, a first current sensor 32, a second current sensor 33, a filter capacitor 4, a first power switch device 51, a second power switch device 52, a third power switch device 53, a fourth power switch device 54, a fifth power switch device 55, a sixth power switch device 56, a first switch 61, a second switch 62, an EMI filter 7, a three-phase motor 8, a first inductor 91, a second inductor 92, a third inductor 93 and a high-voltage battery pack 10.

[0034] The first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 are each combined in series in pairs to form three bridge arms. The power switch can be a controllable semiconductor device such as a metal-oxide-semiconductor field-effect transistor (MOSFET), an insulated-gate bipolar transistor (IGBT), or an intelligent power module (IPM) that internally integrates a switching transistor and an antiparallel diode. The cathode of the antiparallel diode is connected to the collector of the switching transistor, and the anode of the antiparallel diode is connected to the emitter of the switching transistor. As an example, in this embodiment, the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 are all insulated-gate bipolar transistors (IGBTs). The internal structure of the IGBT is equivalent to a switching transistor and a diode in antiparallel connection. The cathode of the diode is connected to the collector of the switching transistor, and the anode of the diode is connected to the emitter of the switching transistor. The emitter of the first power switch device 51 is connected to the collector of the second power switch device 52 to form the first set of bridge arms. The collector terminal of the first power switch device 51 is the high end of the bridge arm, the connection between the emitter of the first power switch device 51 and the collector of the second power switch device 52 is the midpoint of the bridge arm, and the emitter of the second power switch device 52 is the low end of the bridge arm. The emitter of the second power switch device 52 is connected to the negative pole of the high-voltage DC bus interface 21. The emitter of the third power switch device 53 is connected to the collector of the fourth power switch device 54 to form the second set of bridge arms. The collector of the third power switch device 53 is the high end of the bridge arm, the connection between the emitter of the third power switch device 53 and the collector of the fourth power switch device 54 is the midpoint of the bridge arm, and the emitter of the fourth power switch device 54 is the low end of the bridge arm. The emitter of the fourth power switch device 54 is connected to the negative pole of the high-voltage DC bus interface 21. The emitter of the fifth power switch device 55 is connected to the collector of the sixth power switch device 56 to form the third set of bridge arms. The collector of the fifth power switch device 55 is the high end of the bridge arm, the connection between the emitter of the fifth power switch device 55 and the collector of the sixth power switch device 56 is the midpoint of the bridge arm, and the emitter of the sixth power switch device 56 is the low end of the bridge arm. The emitter of the sixth power switch device 56 is connected to the negative pole of the high-voltage DC bus interface 21.

[0035] The common terminal of the first switch 61 is respectively connected to the midpoints of the first set of bridge arms, the second set of bridge arms, and the third set of bridge arms through the second current sensor 33. The first voltage sensor 31 is connected between the positive and negative poles of the high-voltage DC bus interface 21. The two ends of the first current sensor 32 are respectively connected to the positive pole of the high-voltage DC bus 21 and the positive pole of the filter capacitor 4, and the negative pole of the filter capacitor 4 is connected to the negative pole of the high-voltage DC bus interface 21.

[0036] The high - end and low - end of the three bridge arms formed by the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 are connected respectively. The high - end and low - end of the three bridge arms are connected to the positive and negative electrodes of the filter capacitor 4 respectively, and then connected to the positive and negative electrodes of the high - voltage DC bus interface 21.

[0037] The positive and negative electrodes of the high - voltage battery pack 10 are connected to the positive and negative electrodes of the high - voltage DC bus interface 21 respectively. The external power interface 22 is connected to the first inductor 91, the second inductor 92, and the third inductor 93 through the EMI filter 7. The other ends of the first inductor 91 and the second inductor 92 are both connected to the second output terminal S2 of the first switch 61. The other end of the third inductor 93 is connected to the second switch 62, and the other end of the second switch 62 is connected to the second output terminal S2 of the first switch 61. The first output terminal S1 of the first switch 61 is connected to the three - phase motor interface 8. The first voltage sensor 31, the first current sensor 32, the second current sensor 33, the first switch 61, and the second switch 62 are all connected to the VCU respectively.

[0038] In the present invention, direct current can be transmitted to the subsequent circuit interface after voltage conversion through the high - voltage DC bus interface, the filter capacitor, the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device. As an example, the DC voltage can be 800V, or other voltage levels used in automobiles. The high - voltage DC bus interface can be used as a DC output interface in the three - phase AC / DC mode to convert three - phase alternating current into direct current and transmit it to the high - voltage battery pack. In the three - phase DC / AC mode, it can be used as a DC input interface to transmit the energy of the high - voltage battery pack to the subsequent stage and provide three - phase alternating current. The high - voltage DC bus interface can be used as a DC output interface in the single - phase AC / DC mode to convert single - phase alternating current into direct current and transmit it to the high - voltage battery pack. In the single - phase DC / AC mode, it can be used as a DC input interface to transmit the energy of the high - voltage battery pack to the subsequent stage and provide single - phase alternating current. In the bidirectional DC / DC mode, it forms a two - phase interleaved structure, and through appropriate control strategies, the current and voltage ripples can be reduced.

[0039] In the present invention, the power of the high - voltage DC bus interface is converted to the external power interface or the three - phase motor through the power switch device to provide three - phase, single - phase alternating current and direct current. The power of the external power interface or the three - phase motor can also be reversely converted to the high - voltage DC bus interface through the power switch device to provide direct current, realizing bidirectional energy flow.

[0040] After the current sensor and voltage sensor sample the voltage and current signals, they are sent to the VCU. After calculation, the VCU generates PWM signals to control the on / off of the power switch devices to meet the requirements of different conversion modes. The VCU controls the first switch and the second switch to achieve five-mode conversions of bidirectional DC / DC, three-phase AC / DC, three-phase DC / AC, single-phase AC / DC, and single-phase DC / AC. When the second switch is closed, it is three-phase; when the second switch is open, it is single-phase.

[0041] The system of the present invention has 6 functional modes:

[0042] 1. When the system operates in the motor control function, the equivalent circuit schematic diagram is as Figure 2 shown. The first output terminal 1 of the first switch 61 is closed, and the first switch 61 is connected to the three-phase motor interface 8. The first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 form a three-phase full-bridge inverter. The VCU1 generates 6 PWM signals, which are respectively sent to the gates of the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 to achieve precise control of the motor.

[0043] 2. When the system operates in the three-phase DC / AC conversion function, the equivalent circuit schematic diagram is as Figure 3 shown. The second output terminal 2 of the first switch 61 is closed, and the second switch 62 is normally closed. The first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 form a three-phase DC / AC inverter to convert the DC power of the high-voltage battery pack into three-phase alternating current required by the local load or the power grid on the external power interface 22. The VCU1 generates 6 PWM signals, which are respectively sent to the gates of the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56.

[0044] Under this function, the external power supply interface inputs three-phase alternating current, which passes through the EMI filter 7, the first inductor 91, the second inductor 92, the third inductor 93, the second switch 62, and the first switch 61. The VCU controls the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 for rectification to convert the three-phase alternating current into direct current. The VCU adjusts and controls the direct current to ensure that the charging current and voltage are within a safe and stable range to protect the vehicle battery. The adjusted and controlled direct current is transmitted to the high-voltage DC bus interface, and the connection methods of the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 are as described above.

[0045] 3. When the system operates in the three-phase AC / DC conversion function, the equivalent circuit schematic diagram is as Figure 3 shown. The second output terminal 2 of the first switch 61 is closed, and the second switch 62 is normally closed. The first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 form a three-phase AC / DC rectifier to convert the three-phase alternating current on the external power supply interface 22 into the DC power supply of the high-voltage battery pack. The VCU1 generates 6 PWM signals and sends them to the gates of the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 respectively.

[0046] Under this function, the high-voltage DC bus converts the DC power supply of the high-voltage battery pack into three-phase alternating current after inversion by 6 power devices, and transmits the power to the external power supply interface through the first switch 61, the first inductor 91, the second inductor 92, the third inductor 93, the second switch 62, and the EMI filter 7. The VCU adjusts and controls the three-phase alternating current, including the adjustment of parameters such as voltage, frequency, and phase, to meet the requirements of the output alternating current. After being processed by the inverter circuit, the direct current is inverted into three-phase alternating current and output to the required equipment or power grid. The connection methods of the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 are as described above.

[0047] 4. When the system operates in the single-phase DC / AC conversion function, the equivalent circuit schematic diagram is as Figure 4As shown, the second output terminal 2 of the first switch 61 is closed, and the second switch 62 is open. The first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 form a three-phase DC / AC inverter, which converts the DC power supply of the high-voltage battery pack into single-phase alternating current required by the local load on the external power supply interface 22. The VCU1 generates 6 PWM signals and sends them to the gates of the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 respectively.

[0048] In this function, the second output terminal 2 of the first switch 61 is closed, and the second switch 62 is open. The external power supply interface receives single-phase alternating current from the single-phase AC power supply. After passing through the EMI filter 7, the first inductor 91, the second inductor 92, the third inductor 93, and the first switch 61 at the input end, and being rectified by the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56, the single-phase alternating current is converted into direct current. The VCU adjusts and controls the direct current to ensure that the charging current and voltage are within a safe and stable range to protect the vehicle battery. The adjusted and controlled direct current is delivered to the high-voltage DC bus interface. The third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 are connected as described above.

[0049] 5. When the system operates in the single-phase AC / DC conversion function, the equivalent circuit schematic diagram is as Figure 4 As shown, the second output terminal 2 of the first switch 61 is closed, and the second switch 62 is open. The first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 form a single-phase AC / DC rectifier, which converts the single-phase alternating current on the external power supply interface 22 into the DC power supply of the high-voltage battery pack. The VCU1 generates 6 PWM signals and sends them to the gates of the first power switch device 51, the second power switch device 52, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 respectively.

[0050] In this function, the second output terminal 2 of the first switch 61 is closed, and the second switch 62 is open. The high-voltage DC bus converts the DC power supply of the high-voltage battery pack into single-phase alternating current after inversion through the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56, and transmits the power to the external power interface through the first switch 61, the first inductor 91, the second inductor 92, the third inductor 93, and the EMI filter 7. The VCU adjusts and controls the single-phase alternating current, including the adjustment of parameters such as voltage, frequency, and phase, to meet the requirements of the output alternating current. The third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 are connected as described above.

[0051] 6. When the system works in the bidirectional DC / DC conversion function, the equivalent schematic diagram of the circuit is as Figure 5 shown. The second output terminal 2 of the first switch 61 is closed, and the second switch 62 is open. The third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, the sixth power switch device 56, the first inductor 91, the second inductor 92, and the filter capacitor 4 form a bidirectional DC / DC circuit to realize the bidirectional flow of DC power. The VCU1 generates 4 PWM signals and sends them to the gates of the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, and the sixth power switch device 56 respectively.

[0052] In this mode, the second switch 62 is open, and the second output terminal 2 of the first switch 61 is closed. The system can work in the buck mode or the boost mode. In the buck mode, the high-voltage battery pack passes through the high-voltage DC bus interface, is filtered by the filter capacitor, and the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, the sixth power switch device 56, the first DC inductor, and the second DC inductor form a two-phase interleaved Buck circuit to step down the voltage of the high-voltage battery pack and output it to the external power interface, and the output voltage and current magnitude can be controlled. In the boost mode, the DC power supply is input from the external power interface, passes through the EMI filter 7, the first inductor 91, the second inductor 92, the third power switch device 53, the fourth power switch device 54, the fifth power switch device 55, the sixth power switch device 56, and the filter capacitor to form a two-phase interleaved Boost circuit to boost the high-voltage battery pack to the external power interface, and the output voltage and current magnitude can be controlled. To reduce the conduction loss, the four power switch devices can work in the synchronous rectification mode.

[0053] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention.

Claims

1. A vehicle-mounted electric energy management system, characterized in that, Including: The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, the sixth power switch device, the first voltage sensor, the first current sensor, the second current sensor, the filter capacitor, the first switch, the second switch, the EMI filter, the first inductor, the second inductor, the third inductor; VCU, high-voltage DC bus interface, three-phase motor interface, external power supply interface; The emitter of the first power switch device is connected to the collector of the second power switch device to form the first set of bridge arms. The collector terminal of the first power switch device is the high end of the bridge arm. The connection between the emitter of the first power switch device and the collector of the second power switch device is the midpoint of the bridge arm. The emitter of the second power switch device is the low end of the bridge arm, and the emitter of the second power switch device is connected to the negative pole of the high-voltage DC bus interface; The emitter of the third power switch device is connected to the collector of the fourth power switch device to form the second set of bridge arms. The collector of the third power switch device is the high end of the bridge arm. The connection between the emitter of the third power switch device and the collector of the fourth power switch device is the midpoint of the bridge arm. The emitter of the fourth power switch device is the low end of the bridge arm, and the emitter of the fourth power switch device is connected to the negative pole of the high-voltage DC bus interface; The emitter of the fifth power switch device is connected to the collector of the sixth power switch device to form the third set of bridge arms. The collector of the fifth power switch device is the high end of the bridge arm. The connection between the emitter of the fifth power switch device and the collector of the sixth power switch device is the midpoint of the bridge arm. The emitter of the sixth power switch device is the low end of the bridge arm, and the emitter of the sixth power switch device is connected to the negative pole of the high-voltage DC bus interface; The common terminal of the first switch is respectively connected to the midpoints of the first set of bridge arms, the second set of bridge arms, and the third set of bridge arms through the second current sensor; The first voltage sensor is connected between the positive and negative poles of the high-voltage DC bus interface. The two ends of the first current sensor are respectively connected to the positive pole of the high-voltage DC bus and the positive pole of the filter capacitor, and the negative pole of the filter capacitor is connected to the negative pole of the high-voltage DC bus interface; The high ends and low ends of the three bridge arms formed by the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device are respectively connected. The high ends and low ends of the three bridge arms are respectively connected to the positive and negative poles of the filter capacitor and then connected to the positive and negative poles of the high-voltage DC bus interface; The positive and negative poles of the high-voltage battery pack are respectively connected to the positive and negative poles of the high-voltage DC bus interface; The external power supply interface is connected to the first inductor, the second inductor, and the third inductor through the EMI filter. The other ends of the first inductor and the second inductor are both connected to the second output terminal of the first switch. The other end of the third inductor is connected to the second switch, and the other end of the second switch is connected to the second output terminal of the first switch. The first output terminal of the first switch is connected to the three-phase motor interface; The first voltage sensor, the first current sensor, the second current sensor, the first switch, and the second switch are all connected to the VCU respectively. After the current sensor and the voltage sensor sample the voltage and current signals, they are sent to the VCU. After calculation, the VCU generates PWM signals to control the on and off of the power switch devices to meet the requirements of different conversion modes.

2. The on-vehicle electric energy management system according to claim 1, characterized in that, The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device are metal-oxide-semiconductor field-effect transistors, intelligent power modules, and insulated gate bipolar transistors that internally integrate a switching tube and a reverse-parallel diode. The cathode of the reverse-parallel diode is connected to the collector of the switching tube, and the anode of the reverse-parallel diode is connected to the emitter of the switching tube.

3. The on-vehicle power management system according to claim 1, characterized in that, The power of the high-voltage DC bus interface is converted to the external power interface or the three-phase motor through the power switch device, providing three-phase, single-phase alternating current and direct current. The external power interface or the three-phase motor power is reversely converted to the high-voltage DC bus interface through the power switch device to provide direct current, realizing bidirectional energy flow.

4. The on-vehicle power management system according to claim 3, wherein, The high-voltage DC bus interface serves as a DC output interface in the three-phase AC / DC mode, converting three-phase alternating current into direct current and transmitting it to the high-voltage battery pack. In the three-phase DC / AC mode, it serves as a DC input interface, transmitting the energy of the high-voltage battery pack to the subsequent stage to provide three-phase alternating current; the high-voltage DC bus interface serves as a DC output interface in the single-phase AC / DC mode, converting single-phase alternating current into direct current and transmitting it to the high-voltage battery pack. In the single-phase DC / AC mode, it serves as a DC input interface, transmitting the energy of the high-voltage battery pack to the subsequent stage to provide single-phase alternating current; in the bidirectional DC / DC mode, it forms a two-phase interleaved structure to reduce current and voltage ripples.

5. The on-vehicle power management system according to claim 1, characterized in that, The first output terminal of the first switch is closed, and the first switch is connected to the three-phase motor interface. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase full-bridge inverter. The VCU uses space vector pulse width modulation (SVPWM) to generate six PWM signals, which are respectively sent to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device. The energy directly flows from the high-voltage battery pack to the three-phase motor connected to the first switch, realizing precise control of the motor.

6. The on-vehicle power management system according to claim 1, characterized in that, The second output terminal of the first switch is closed, and the second switch is normally closed. The first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase DC / AC inverter, converting the DC power of the high-voltage battery pack into three-phase alternating current required by the local load or the power grid on the external power interface. The VCU generates six PWM signals, which are respectively sent to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device.

7. The in-vehicle power management system according to claim 1, wherein, The second output terminal of the first switch is closed, the second switch is normally closed, and the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase AC / DC rectifier, which converts the three-phase alternating current on the external power supply interface into the direct current power supply of the high-voltage battery pack. The VCU generates six PWM signals and sends them to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device respectively.

8. The in-vehicle power management system according to claim 1, wherein The second output terminal of the first switch is closed, the second switch is open, and the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a three-phase DC / AC inverter, which converts the direct current power supply of the high-voltage battery pack into the single-phase alternating current required by the local load on the external power supply interface. The VCU generates six PWM signals and sends them to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device respectively.

9. The on-vehicle power management system according to claim 1, wherein The second output terminal of the first switch is closed, the second switch is open, and the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device form a single-phase AC / DC rectifier, which converts the single-phase alternating current on the external power supply interface into the direct current power supply of the high-voltage battery pack. The VCU generates six PWM signals and sends them to the gates of the first power switch device, the second power switch device, the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device respectively.

10. The on-vehicle power management system according to claim 1, wherein, The second output terminal of the first switch is closed, the second switch is open, and the third power switch device, the fourth power switch device, the fifth power switch device, the sixth power switch device, the first inductor, the second inductor, and the filter capacitor form a bidirectional DC / DC circuit to achieve bidirectional flow of the direct current power supply. The VCU generates PWM signals and sends them to the gates of the third power switch device, the fourth power switch device, the fifth power switch device, and the sixth power switch device respectively.

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