Electric vehicle with synchronous switching converter

Abstract

The invention provides a motorized vehicle with a synchronous switching converter. An electrically powered vehicle includes: a synchronous switch DC / DC voltage converter; a switch configured to selectively connect the external charging terminal to the traction battery, the voltage converter, and the external load terminal; and at least one controller programmed to, based on a nominal voltage of the traction battery related to a voltage at the external charging terminal and a requested voltage supplied to the external load terminal, determine a voltage at the external charging terminal based on the nominal voltage. The voltage converter is operated and the switch is controlled to connect the external charging terminal to the voltage converter and the external load terminal. An associated method includes controlling a plurality of switches to selectively connect an external charging electron, a voltage converter, and an external load terminal; and controlling the voltage converter to operate to increase or decrease the voltage based on which one or more of the voltage converter, the external charging terminal, the external load terminal, and the traction battery are connected through the plurality of switches.

Description

Technical Field

[0001] The present application relates to a synchronous switching converter that supports output power and DC fast charging of an electrified vehicle. Background Art

[0002] Electrified vehicles (including electric vehicles and hybrid vehicles) can be used in various commercial applications where the assembler needs to supply power to assembled equipment (e.g., such as refrigeration units and hydraulic motors). For equipment that is powered directly from the vehicle traction battery, the wide range of battery voltages on existing and future vehicles may make compatibility a challenge. This may require the assembler to have different variants of equipment to support different vehicle battery voltages. Voltage ripple generated by other components on the high-voltage bus is also a potential issue that can create compatibility challenges. Voltage compatibility is also an issue between existing electric vehicle supply equipment (EVSE) that can operate at 400V or 800V for DC fast charging and associated electrified vehicle architectures that can utilize, for example, 800V traction battery packs. For example, other challenges for various commercial applications may include simultaneously providing power and DC fast charging to external loads, reducing voltage ripple on the external load side, and supporting both 400V and 800V external loads. Summary of the invention

[0003] In various embodiments, an electrified vehicle includes: an electric machine arranged to selectively provide propulsion torque to wheels of the electrified vehicle; a traction battery electrically coupled to the electric machine; a synchronous switching DC / DC voltage converter; a plurality of switches configured to selectively connect an external charging terminal to the traction battery, the voltage converter, and an external load terminal; and at least one controller programmed to selectively operate the voltage converter and control the plurality of switches to connect the external charging terminal to the voltage converter and the external load terminal based on a nominal voltage of the traction battery related to a voltage detected at the external charging terminal and a requested voltage supplied to the external load terminal. The one or more controllers may be programmed to, in response to the voltage detected at the external charging terminal being a DC voltage within a predetermined range of the nominal voltage of the traction battery, control a first switch of the plurality of switches to connect at least one of the external charging terminals to the traction battery, and control at least a second switch of the plurality of switches to disconnect at least one of the external load terminals from the voltage converter and the traction battery to charge the traction battery. The one or more controllers may be programmed to, in response to a voltage detected at the external charging terminal being a DC voltage outside the predetermined range of a nominal voltage of the traction battery and less than the nominal voltage, control a first switch of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery, control at least a second switch of the plurality of switches to connect at least one of the external load terminals to the voltage converter, and control the voltage converter to increase the DC voltage from the external charging terminal to the nominal voltage of the traction battery to charge the traction battery.

[0004] In one or more embodiments, the one or more controllers are programmed to, in response to the requested voltage supplied to the external load terminal being a DC voltage less than the nominal voltage of the traction battery and the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery: control a first switch of the plurality of switches to connect at least one of the external charging terminals to the traction battery and a high voltage terminal of the voltage converter; control a second switch of the plurality of switches to disconnect at least one of the external charging terminals from a low voltage terminal of the voltage converter; control at least a third switch of the plurality of switches to connect the low voltage terminal of the voltage converter to one of the external charging terminals; and control the voltage converter to reduce the DC voltage detected at the external charging terminal to the requested voltage supplied to the external load terminal. The one or more controllers may also be programmed to, in response to the requested voltage supplied to the external load terminal being a DC voltage less than the nominal voltage of the traction battery and the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery, control at least a fourth switch of the plurality of switches to disconnect the traction battery from the external load terminal.

[0005] In one embodiment, the one or more controllers are programmed to, in response to a requested voltage supplied to the external load terminal and a voltage detected at the external charge terminal being a DC voltage less than a nominal voltage of the traction battery: control a first switch of the plurality of switches to disconnect at least one of the external charge terminals from the traction battery and a high voltage terminal of the voltage converter; control a second switch of the plurality of switches to connect at least one of the external charge terminals to a low voltage terminal of the voltage converter; control at least a third switch of the plurality of switches to connect at least one of the external charge terminals to at least one of the external load terminals; and control the voltage converter to increase the DC voltage detected at the external charge terminal to the nominal voltage of the traction battery. The one or more controllers may also be programmed to, in response to a requested voltage supplied to the external load terminal and a voltage detected at the external charge terminal being a DC voltage less than a nominal voltage of the traction battery, control at least a fourth switch of the plurality of switches to disconnect the traction battery from the external load terminal.

[0006] In various embodiments, the one or more controllers are further programmed to, in response to the requested voltage supplied to the external load terminal and the voltage detected at the external charging terminal being a DC voltage less than a nominal voltage of the traction battery: control at least a fourth switch of the plurality of switches to connect the traction battery to the external load terminal; and control at least a fifth switch of the plurality of switches to disconnect the low voltage terminal of the voltage converter from at least one of the external load terminals.

[0007] In one or more embodiments, the one or more controllers are programmed to, in response to the requested voltage supplied to the external load terminals being a DC voltage that is less than a nominal voltage of the traction battery: control a first switch of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery and a high voltage terminal of the voltage converter; control a second switch of the plurality of switches to disconnect at least one of the external charging terminals from a low voltage terminal of the voltage converter; control at least a third switch of the plurality of switches to connect the low voltage terminal of the voltage converter to at least one of the external load terminals; control at least a fourth switch of the plurality of switches to disconnect the traction battery from at least one of the external load terminals; and control the voltage converter to reduce the DC voltage from the traction battery to the requested voltage supplied to the external load terminals.

[0008] Embodiments also include a method for controlling an electrified vehicle having: a traction battery electrically connected to an electric machine; a synchronous DC / DC voltage converter; and a plurality of switches configured to selectively connect an external charging terminal to the voltage converter, the traction battery, and an external load terminal, the method comprising, by a vehicle controller based on a nominal voltage of the traction battery related to a DC voltage detected at the external charging terminal and a predetermined DC voltage selectively delivered to the external load terminal: controlling the plurality of switches to selectively connect the external charging terminal, the voltage converter, and the external load terminal; and controlling the voltage converter to operate to increase or decrease voltage based on which one or more of the voltage converter, the external charging terminal, the external load terminal, and the traction battery are connected via the plurality of switches.

[0009] In various embodiments, the plurality of switches include: a first switch between a first one of the external charge terminals and the traction battery; a second switch between the first external charge terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charge terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch. In one operational configuration, the method further includes, in response to a DC voltage detected at the external charge terminal being within a predetermined range of a nominal voltage of the traction battery: closing the first switch; opening the second, third, fourth, and fifth switches; and disabling the voltage converter. In another operational configuration, the method further includes, in response to a DC voltage detected at the external charge terminal being less than a nominal voltage of the traction battery: opening the first, third, fourth, and fifth switches; closing the second switch; and operating the voltage converter to increase the voltage from the external charge terminal to the nominal voltage of the traction battery.

[0010] In another operational configuration, the method further includes, in response to the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery and the predetermined DC voltage being less than the nominal voltage of the traction battery: closing the first switch, the third switch, and the fourth switch; opening the second switch and the fifth switch; and operating the voltage converter to reduce the voltage from the external charging terminal to the predetermined DC voltage. In another operational configuration, the method further includes, in response to the DC voltage detected at the external charging terminal and the predetermined DC voltage both being less than the nominal voltage of the traction battery: closing the second switch, the third switch, and the fourth switch; opening the first switch and the fifth switch; and operating the voltage converter to increase the voltage from the external charging terminal to the nominal voltage of the traction battery. In another operating configuration, the method further includes, in response to the absence of a DC voltage detected at the external charging terminal and the predetermined DC voltage being less than a nominal voltage of the traction battery: closing the third switch and the fourth switch; opening the first switch, the second switch, and the fifth switch; and operating the voltage converter to reduce the voltage from the traction battery to a predetermined DC voltage supplied to the external load terminal. In another operating configuration, the method further includes closing the fourth switch and the fifth switch; opening the first switch, the second switch, and the third switch; and disabling the voltage converter to provide an unregulated traction battery voltage to the external load terminal. In another operating configuration, the method further includes, in response to the DC voltage detected at the external charging terminal being within a predetermined range of a nominal traction battery voltage: closing the first switch, the fourth switch, and the fifth switch; opening the second switch and the third switch; and disabling the voltage converter to provide an unregulated voltage from the external charging terminal to the external load terminal.

[0011] In one or more embodiments, an electrified vehicle system includes: a traction battery; a bidirectional synchronous DC / DC voltage converter; a plurality of switches configured to selectively connect at least one of the voltage converter and the traction battery to at least one of an external charging terminal and an external load terminal; and a controller programmed to operate the voltage converter in one of a disabled mode, a boost mode, and a buck mode based on which of the voltage converter, the traction battery, the external charging terminal, and the external load terminal is connected and in response to a voltage of the traction battery related to a voltage detected at the external charging terminal and a voltage supplied to the external load terminal. The plurality of switches may be implemented by: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch. The controller may be programmed to operate the plurality of switches and the voltage converter to simultaneously supply power from the external charging terminals to the traction battery and the external load terminals.

[0012] One or more embodiments may have various associated advantages over isolated dedicated DC / DC converter modules to support assembled or external loads. For example, an integrated synchronous switching converter design may reduce required materials and associated mass, reduce packaging space, and enable higher power to be supplied to power output (ePTO) loads to facilitate assembled commercial applications for electrified vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a block diagram illustrating a representative electrified vehicle including a bidirectional synchronous DC / DC voltage converter and a switch arrangement according to one or more embodiments.

[0014] Figure 2 is a diagram showing a representative embodiment of a system or method for controlling an electrified vehicle system having a bidirectional synchronous DC / DC voltage converter and a switch arrangement according to the present disclosure.

[0015] Figure 3 It shows that according to Figure 2 A simplified flow chart of the operation of a representative configuration of an embodiment of a bidirectional synchronous DC / DC voltage converter and a switch arrangement.

[0016] Figure 4 It shows that according to Figure 2 Schematic diagram of an embodiment of a bidirectional synchronous DC / DC voltage converter and other configurations of a switch arrangement. DETAILED DESCRIPTION

[0017] As required, detailed representative examples of the claimed subject matter are disclosed herein; however, it should be understood that the disclosed examples are merely representative and can be implemented in various and alternative forms. The drawings are not necessarily drawn to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, the specific structural and functional details disclosed herein should not be interpreted as limiting, but merely as a representative basis for teaching those skilled in the art to employ the claimed subject matter in different ways.

[0018] In one or more embodiments, an electrified vehicle includes a synchronous switching converter that supports both step-up and step-down operations for a DC (direct current) EVSE (electrified vehicle supply equipment) that cannot operate at the nominal high voltage of the traction battery to supply power to an assembled or external load operating at a voltage lower (higher) than the traction battery and / or EVSE. The system is designed to provide flexibility to accommodate a variety of electrified vehicle applications, including commercial vehicles equipped with additional equipment. The system may include an 800V traction battery and accommodate 400V and 800V DC fast charging, for example, supplying an external (or assembled equipment) load at 400V or 800V while simultaneously performing DC fast charging of the traction battery, and supplying a 400V external load when disconnected from the EVSE. The system may also include a bypass mode to support unregulated power supply from the EVSE to the assembled load when the load requires more power than the synchronous HV / HV DC / DC switching converter can supply.

[0019] Figure 1 An example of an electrified vehicle 100 is depicted, which is implemented in this example as a battery electric vehicle (BEV), but generally represents any electrified vehicle such as, for example, a plug-in hybrid electric vehicle (PHEV). The electrified vehicle 100 may include one or more three-phase electric machines 104 that may be controlled to provide torque to wheels. The electric machines 104 may operate as motors, generators, or both, and may extend the vehicle's range by recovering energy during regenerative braking.

[0020] The traction battery or battery pack 114 stores energy that can be used by the motor 104 and / or can be used to power various on-board and external vehicle loads. The vehicle battery pack 114 typically provides a high voltage (HV) DC output provided by connecting hundreds of low voltage cells together. The battery pack 114 is electrically connected to one or more traction inverters 116. The traction inverter 116 is also electrically connected to the motor 104 and provides the ability to transfer energy bidirectionally between the battery pack 114 and the motor 104. For example, a typical battery pack 114 can provide a DC voltage / current, while the motor 104 may require a three-phase AC voltage / current. The traction inverter 116 can convert the DC voltage into a three-phase AC current as required by the motor 104, and may also be referred to as a power electronics module in various applications. The traction inverter 116 may also include a voltage converter that increases the DC voltage supplied from the battery pack 114 to the HV DC bus that powers the inverter. In the regeneration mode, the traction inverter 116 converts the three-phase AC current from the electric machine 104 acting as a generator to the DC voltage required to recapture energy in the battery pack 114 .

[0021] In addition to providing energy for propulsion, the battery pack 114 can also provide energy for other vehicle electrical systems and external loads to facilitate the vehicle assembler to add specialized equipment for specific applications. When operating in a buck mode or direction, the bidirectional synchronous HV / HV DC / DC converter module 118 converts the higher HV DC output of the battery pack 114 to a lower HV DC supply, and when operating in a boost mode or direction, converts the lower HV DC input from the external supply to a higher HV DC voltage compatible with other vehicle loads such as HV auxiliary loads (ePTO) 250. Other HVDC loads such as compressors and electric heaters can be connected directly from the battery pack 114 to the high voltage bus. External load terminals that facilitate the assembly of commercial vehicles can be supplied with higher HV DC voltages (such as 800V) or lower HV DC voltages (such as 400V), both of which exceed 60V and are therefore considered "high" voltages for electric mobility applications, depending on the specific application and implementation. In a typical vehicle, low voltage (LV) auxiliary loads 132 are electrically connected to a 12V, 24V, or 48V LV battery 120. The HV / LV DC / DC converter 115 may convert the HV bus voltage to an LV bus voltage that is compatible with the LV auxiliary battery 120 and the LV auxiliary loads 132. For example, as explained in more detail herein, the traction battery 114 may operate at a higher DC voltage, such as 800V DC, where a commercial vehicle has external load terminals supplied with 800V DC or 400V DC to facilitate fitting equipment with higher power requirements than a typical passenger vehicle.

[0022] The battery pack 114 can be recharged by an external power source via an electric vehicle supply equipment (EVSE) 126. The EVSE 126 can provide AC or DC power to the vehicle 102 by electrically connecting to the external charging terminals via the charging port 124. As described in more detail herein, the EVSE (when connected) can also supply power to the external load terminals to facilitate powering the assembled equipment 250 and charging the traction battery 114 at the same time. The charging port 124 can be any type of port configured to transfer power from the EVSE 126 to the vehicle 100. The charging port 124 can be electrically connected to an on-board charger 122, sometimes referred to as a power conversion module or charging module. The on-board charger 122 can regulate the power from the EVSE 126 to provide the appropriate voltage and current levels to the battery pack 114. In some applications, the EVSE 126 can be configured to provide the appropriate voltage and current levels to the battery pack 114, and the on-board charger 122 may not be necessary. In some applications, the functionality of the on-board charger 122 may reside in the EVSE 126 . For example, when implemented as a DC fast charger, the EVSE 126 provides constant power at a DC voltage between 200 V and 1000 V. DC fast charging (DCFC) may bypass the on-board charger 122 .

[0023] The vehicle motor, battery, traction inverter, DC / DC converter and various other control modules, components or systems may be controlled by a vehicle or powertrain controller or control module (PCM) 128. Alternatively or in combination, the various systems or subsystems may include associated control modules or controllers that communicate with the PCM 128 via a vehicle wired or wireless network to provide coordinated control of the vehicle. As used in this disclosure, a controller generally refers to one or more control modules or controllers that can collaborate to perform a specific task or function, and is not limited to a single controller or any particular dedicated controller or control module.

[0024] The controller 128 may receive input from a human machine interface (HMI) 130 and store associated user preferences in a non-transitory computer readable storage medium or memory (not shown). The user preferences may include a specified configuration or operating mode of the HV / HVDC / DC voltage converter 118 and switch arrangement according to the present disclosure. Alternatively, a selectively connected programming tool, DIP switch, jumper, or other continuous signaling strategy may be used to select the configuration or operating mode, which the controller 128 uses to control the HV / HV DC / DC voltage converter 118 and associated switch arrangement to control the external charging terminal ( Figure 2 ), HV / HV DC / DC voltage converter 118, traction battery 114 and external load terminals ( Figure 2 ) between them.

[0025] Figure 2 is a diagram showing a representative embodiment of a system or method for controlling an electrified vehicle system having a bidirectional synchronous HV / HV DC / DC voltage converter and a switch arrangement according to the present disclosure. Figure 2 The various switches, switch groups, and contactors shown in the drawings are controlled by one or more controllers (such as the vehicle controller 128) to open and close in response to corresponding control signals. For example, the switches, switch groups, and contactors may be implemented by electromechanical or solid-state devices (such as MOSFETs or IGBTs) on one or more substrates or chips.

[0026] The EVSE 126 provides DC fast charging (DCFC) via a cable that can be connected to the charging port 124 of the electrified vehicle 100 to provide power to the first external charging terminal 202 and the second external charging terminal 204, respectively. In the representative embodiment, power can be supplied at 800 V (which corresponds to the nominal voltage of the traction battery 114) or 400 V. Of course, representative voltage values ​​may vary depending on the specific implementation of the DCFC EVSE and vehicle architecture.

[0027] Switch group 206 (SG2) includes switches or contactors 208, 210 that are controlled by an associated controller (such as controller 128 ( Figure 1 )) operate together to operate based on and with respect to Figure 4 The states of the various switches shown in the representative use case in FIG. 1 connect the external charging terminals 202, 204 to the switch arrangement and the bidirectional synchronous switching DC / DC voltage converter 118. The first switch 212 (S3) is positioned between the first external charging terminal 202 and the corresponding terminal of the traction battery 114, which can be controlled by one or more vehicle controllers (such as controller 128 ( Figure 1)) is selectively connected to the vehicle electrical bus by operation of the battery main contactors 216, 218 of the switch group 214 (SG1) controlled by the control system. The second switch 222 (S4) is positioned between the first external charging terminal 202 and the low voltage terminal 230 of the HV / HV DC / DC voltage converter 118. The high voltage terminal 232 of the HV / HV DC / DC voltage converter 118 is connected to the first terminal of the traction battery 114 via the contactor 216, and is connected to the third switch 236 (S5). The third switch 236 (S5) is positioned between the second switch 222 (S4) and the first terminal 260 of the external load 250. The negative terminal or common terminal 234 of the DC / DC voltage converter 118 is connected to the second external charging terminal 204 (via the contactor 210), to the negative terminal of the traction battery 114 (via the contactor 218), and to the fourth switch 238 (S6). The fourth switch 238 (S6) is positioned between the second external charging terminal 204 and the second external load terminal 262. The fifth switch 240 ( S7 ) is positioned between the first switch 212 ( S3 ) and the third switch 236 ( S5 ).

[0028] Also like Figure 2 As shown, the controller 228 can provide switch enable signals to the associated transistors Q1 and Q2 of the voltage converter 118, and receive feedback signals from the external load (ePTO) current sensors 242, 244, and communicate with the external load via the communication signal line 270 to provide a load enable signal to the load enable switch 252 to selectively power the external load 250. Depending on the particular use case or scenario, the controller 228 can disable the bidirectional synchronous switching voltage converter 118, operate the voltage converter 118 in a buck direction / mode, wherein power is provided to the high voltage terminal 230, which is converted to a low voltage at the low voltage terminal 232 by the operation of the switches / transistors Q1, Q2, or operate the converter 118 in a boost direction / mode, wherein power is provided to the low voltage terminal 232 and converted to a high voltage at the high voltage terminal 230. During the pre-charging of the external load circuit, the same as described above can be used. Figure 4 The different directions / modes during steady-state operation are indicated in the representative use cases shown. In one embodiment, the voltage converter 118 can be operated in a buck direction / mode to convert 800V power supplied by the traction battery 114 or the external DCFC 126 to 400V power provided to the external load 250. Similarly, the voltage converter 118 can be operated in a boost direction / mode to convert 400V power supplied by the external DCFC 126 to 800V power for charging the traction battery 114 and / or providing 800V power to the external load 250. Likewise, the boost direction / mode can be enabled to convert 800V power from the traction battery 114 to 400V power for supplying to the external load 250.

[0029] Figure 3 1 is a flow chart illustrating the operation of a representative system or method for controlling an electrified vehicle bidirectional synchronous switch HV / HV DC / DC voltage converter and switch arrangement according to the present disclosure. One or more controllers (such as controller 128 ( Figure 1 ) and 228( Figure 2 )) can cooperate with one or more other controllers to perform one or more control functions described herein. The control logic, functions, codes, software, strategies, etc. executed by one or more processors or controllers (such as controllers 128, 228) can be represented by the block diagrams, charts or flow charts shown in the various figures. Figure 3 The flowchart or block diagram 300 shows a representative control strategy, algorithm and / or logic for operating an electrified vehicle voltage converter and a plurality of associated switches to achieve selective connection between external charging terminals, a voltage converter, a traction battery, and external load terminals for various use cases and corresponding configurations. Depending on the specific application and implementation, one or more processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, etc. may be utilized. To this end, the various steps or functions shown or described may be performed in the order shown or described, in parallel, or omitted in some cases. Although not always explicitly shown or described, a person of ordinary skill in the art will recognize that one or more of the steps or functions may be repeatedly performed depending on the specific processing strategy used. Similarly, the processing order is not necessarily required to achieve the features and advantages described herein, but is provided for ease of illustration and description of representative use scenarios. The control logic may be implemented primarily in software executed by a microprocessor-based vehicle, powertrain, or other controller or control module. Of course, depending on the specific application, the control logic may be implemented in software, hardware, or a combination of software and hardware in one or more controllers. When implemented in software, the control logic may be provided in one or more non-transitory computer-readable storage devices or media storing data representing code or instructions executed by a computer or controller to control the electrified vehicle.

[0030] refer to Figures 2 to 4 , the control strategy 300 corresponds to a representative use case (430, Figure 4), the representative use case corresponds to connecting to an 800V DC fast charger (DCFC) as represented at 310 to provide 400V power to the traction battery and to the external load terminals (also known as electric PTO or power take-off (ePTO) terminals) simultaneously. The vehicles exchange associated charging information and handshake communication signals to initialize the transfer of power from the DCFC EVSE to the electrified vehicle, as represented at 312. The controller then closes switch S3, as represented at 314. As represented at 316, switch group SG1 (traction battery main contactor with two contactors / switches controlled together) is closed to electrically connect the traction battery. Charging cable diagnostics / checks and pre-charge voltages are applied at 318, and then switch group SG2 (external charging terminal contactors) are closed, thereby connecting the 800V power from the DCFC EVSE to deliver charging power, as represented at 322. The controller then closes switches S5 and S6 at 324 to connect the external load terminals. The DC / DC voltage converter is enabled and operates in buck mode or direction to convert the high voltage (800V) to a low voltage (400V) and provide current to pre-charge the external load terminals of the ePTO bus, as indicated at 326. The ePTO load is then enabled at 328 to simultaneously provide 400V power to the external load terminals while charging the traction battery at a nominal battery voltage of 800V.

[0031] Figure 4 Switch arrangements and representative operation or startup sequencing of a DC / DC voltage converter for various representative use cases or scenarios are shown. Figures 2 to 4 , each use case or scenario 410, 420, 430, 440, 450, 460, 470 and 480 shows a representative sequence (indicated by the sequence number in brackets) for controlling the following items: switch groups SG1 and SG2, switches S3, S4, S5, S6, S7, and the DC / DC voltage converter is disabled or enabled and operates in buck mode / direction or in boost mode / direction during ePTO pre-charge operation and subsequent steady state operation after receiving the ePTO load enable signal. The use cases shown are representative and can vary based on the specific application and implementation. Similarly, the representative use cases are not exhaustive, and the system can be controlled to facilitate other use cases.

[0032] In use case 410, the system is controlled to provide traction battery charging from a DCFC that provides a voltage within a predetermined range of the nominal voltage of the traction battery (800V in this example) without simultaneously powering external loads. As indicated by the sequence numbering, S3 is closed, followed by the traction battery main contactor SG1, and then the external charging contactor SG2. Switches S4, S5, S6, S7 are open, and no external load pre-charging is required because no external load is powered. Similarly, the load enable switch is open or disabled, and the DC / DC voltage converter is disabled because no voltage conversion is required between the DCFC EVSE and the traction battery.

[0033] In use case 420, the vehicle is connected to a 400V DCFC EVSE to charge the traction battery without directly powering any external loads. The startup sequence begins with switch S4 being closed to connect the low voltage terminals of the DC / DC voltage converter to the associated external charging terminals. The battery main contactor (SG1) is then closed, followed by the external charging contactor (SG2). Switches S3, S5, S6, and S7 are opened, with the voltage converter operating in a boost mode / direction to boost the external charging voltage (400V) from the external charging terminals to the nominal traction battery voltage (800V) provided at the high voltage terminal 232 of the voltage converter and connected to the traction battery through the battery contactor SG1 to provide charging power to the battery. Since no external loads are powered, ePTO pre-charging is not required and the ePTO load enable switch or signal is disabled.

[0034] Use Case 430 Previously on Figure 3 A flow chart is described and provides simultaneous traction battery charging (at 800 V) and powering of external loads from an external DCFC (at 400 V).

[0035] Use case 440 provides simultaneous traction battery charging (at 800V) and powering of an external load (at 400V) from an external DCFC operating at 400V, thereby operating the DC / DC voltage converter in a buck direction to step down the 800V traction battery voltage for pre-charging the external load circuit during ePTO pre-charging, and then operating the DC / DC voltage converter in a boost direction to step up the 400V power from the DCFC EVSE to the 800V nominal traction battery voltage and charge the traction battery.

[0036] Use cases 450, 460 are situations where the electrified vehicle is not connected to an external DCFC. In use case 450, the system is controlled to provide 400V power to the external load. Therefore, the DC / DC voltage converter operates in the buck direction to reduce the traction battery voltage from 800V to 400V to pre-charge the external load circuit and to provide steady-state power to the external load. In use case 460, the DC / DC voltage converter operates in the buck direction during pre-charging of the external load circuit, but is then disabled to provide an unregulated battery voltage to the external load.

[0037] Use cases 470, 480 provide unregulated power to an external load while simultaneously charging a traction battery. In use case 470, the external power is provided by an 800V DCFC EVSE, such that the DC / DC converter is operated in a buck direction for pre-charging the external load circuit and then disabled, wherein unregulated 800V power is provided to the external load. In use case 480, the external power is provided by a 400V DCFC EVSE, wherein the DC / DC voltage converter is operated in a buck direction during pre-charging of the external load circuit and then in a boost direction to boost 400V power from the DCFC to 800V power to charge the traction battery. The switch arrangement is controlled to provide 400V unregulated power to the external load.

[0038] Although representative examples are described above, these examples are not intended to describe all possible forms or implementations of the claimed subject matter. The words used in the specification are descriptive rather than restrictive, and it should be understood that various changes can be made without departing from the scope of the claims. In addition, the features of various implementation examples can be combined with one or more features from other examples to form other examples or embodiments of the claimed subject matter, regardless of whether the specific combination of features is explicitly shown or described in detail. Although one or more examples or features may have been described as providing advantages over other examples or prior art implementations with respect to one or more desired characteristics, it is recognized by those of ordinary skill in the art that one or more features or characteristics may be compromised to achieve the desired overall system properties, depending on the specific application and implementation. Therefore, examples described as being less desirable than other examples or prior art implementations in terms of one or more characteristics are within the scope of the present disclosure and may be desirable for specific applications.

[0039] According to the present invention, an electrified vehicle is provided, having: an electric machine arranged to selectively provide propulsion torque to wheels of the electrified vehicle; a traction battery electrically coupled to the electric machine; a synchronous switching DC / DC voltage converter; a plurality of switches configured to selectively connect external charging terminals to the traction battery, the voltage converter, and external load terminals; and at least one controller programmed to selectively operate the voltage converter and control the plurality of switches to connect the external charging terminals to the voltage converter and the external load terminals based on a nominal voltage of the traction battery related to a voltage detected at the external charging terminals and a requested voltage supplied to the external load terminals.

[0040] According to an embodiment, the at least one controller is programmed to, in response to a voltage detected at the external charging terminal being a DC voltage within a predetermined range of a nominal voltage of the traction battery, control a first switch of the plurality of switches to connect at least one of the external charging terminals to the traction battery; and control at least a second switch of the plurality of switches to disconnect at least one of the external load terminals from the voltage converter and the traction battery to charge the traction battery.

[0041] According to an embodiment, the at least one controller is programmed to, in response to a voltage detected at the external charging terminal being a DC voltage outside the predetermined range of a nominal voltage of the traction battery and less than the nominal voltage, control a first switch of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery; control at least a second switch of the plurality of switches to connect at least one of the external load terminals to the voltage converter; and control the voltage converter to increase the DC voltage from the external charging terminal to the nominal voltage of the traction battery to charge the traction battery.

[0042] According to an embodiment, the at least one controller is programmed to, in response to the requested voltage supplied to the external load terminals being a DC voltage less than the nominal voltage of the traction battery and the DC voltage detected at the external charging terminals being within a predetermined range of the nominal voltage of the traction battery: control a first switch of the plurality of switches to connect at least one of the external charging terminals to the traction battery and a high voltage terminal of the voltage converter; control a second switch of the plurality of switches to disconnect at least one of the external charging terminals from a low voltage terminal of the voltage converter; control at least a third switch of the plurality of switches to connect the low voltage terminal of the voltage converter to one of the external charging terminals; and control the voltage converter to reduce the DC voltage detected at the external charging terminals to the requested voltage supplied to the external load terminals.

[0043] According to an embodiment, the at least one controller is further programmed to, in response to the requested voltage supplied to the external load terminal being a DC voltage less than a nominal voltage of the traction battery and the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery, control at least a fourth switch of the plurality of switches to disconnect the traction battery from the external load terminal.

[0044] According to an embodiment, the at least one controller is programmed to, in response to the requested voltage supplied to the external load terminals and the voltage detected at the external charging terminals being a DC voltage less than the nominal voltage of the traction battery: control a first switch of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery and the high voltage terminals of the voltage converter; control a second switch of the plurality of switches to connect at least one of the external charging terminals to a low voltage terminal of the voltage converter; control at least a third switch of the plurality of switches to connect at least one of the external charging terminals to at least one of the external load terminals; and control the voltage converter to increase the DC voltage detected at the external charging terminals to the nominal voltage of the traction battery.

[0045] According to an embodiment, the at least one controller is further programmed to, in response to the requested voltage supplied to the external load terminal and the voltage detected at the external charging terminal being a DC voltage less than a nominal voltage of the traction battery, control at least a fourth switch of the plurality of switches to disconnect the traction battery from the external load terminal.

[0046] According to an embodiment, the at least one controller is further programmed to, in response to the requested voltage supplied to the external load terminal and the voltage detected at the external charging terminal being a DC voltage less than a nominal voltage of the traction battery: control at least a fourth switch of the plurality of switches to connect the traction battery to the external load terminal; and control at least a fifth switch of the plurality of switches to disconnect the low voltage terminal of the voltage converter from at least one of the external load terminals.

[0047] According to an embodiment, the at least one controller is programmed to, in response to the requested voltage supplied to the external load terminals being a DC voltage that is less than a nominal voltage of the traction battery: control a first switch of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery and a high voltage terminal of the voltage converter; control a second switch of the plurality of switches to disconnect at least one of the external charging terminals from a low voltage terminal of the voltage converter; control at least a third switch of the plurality of switches to connect the low voltage terminal of the voltage converter to at least one of the external load terminals; control at least a fourth switch of the plurality of switches to disconnect the traction battery from at least one of the external load terminals; and control the voltage converter to reduce the DC voltage from the traction battery to the requested voltage supplied to the external load terminals.

[0048] According to the present invention, a method for controlling an electrified vehicle having: a traction battery electrically coupled to an electric machine; a synchronous DC / DC voltage converter; a plurality of switches configured to selectively connect an external charging terminal to the voltage converter, the traction battery, and an external load terminal, comprising, by a vehicle controller, based on a nominal voltage of the traction battery related to a DC voltage detected at the external charging terminal and a predetermined DC voltage selectively delivered to the external load terminal: controlling the plurality of switches to selectively connect the external charging terminal, the voltage converter, and the external load terminal; and controlling the voltage converter to operate to increase or decrease voltage based on which one or more of the voltage converter, the external charging terminal, the external load terminal, and the traction battery are connected via the plurality of switches.

[0049] In one aspect of the present invention, the plurality of switches include: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch, the method further comprising, in response to a DC voltage detected at the external charging terminal being within a predetermined range of a nominal voltage of the traction battery: closing the first switch; opening the second, third, fourth, and fifth switches; and disabling the voltage converter.

[0050] In one aspect of the present invention, the plurality of switches include: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch, the method further comprising, in response to a DC voltage detected at the external charging terminal being less than a nominal voltage of the traction battery: opening the first switch, the third switch, the fourth switch, and the fifth switch; closing the second switch; and operating the voltage converter to increase a voltage from the external charging terminal to the nominal voltage of the traction battery.

[0051] In one aspect of the present invention, the plurality of switches include: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch, the method further comprising, in response to a DC voltage detected at the external charging terminal being within a predetermined range of a nominal voltage of the traction battery and the predetermined DC voltage being less than the nominal voltage of the traction battery: closing the first switch, the third switch, and the fourth switch; opening the second switch and the fifth switch; and operating the voltage converter to reduce a voltage from the external charging terminal to the predetermined DC voltage.

[0052] In one aspect of the present invention, the plurality of switches include: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first opening and closing of the third switch, the method further comprising, in response to both the DC voltage detected at the external charging terminal and the predetermined DC voltage being less than a nominal voltage of the traction battery: closing the second switch, the third switch, and the fourth switch; opening the first switch and the fifth switch; and operating the voltage converter to increase the voltage from the external charging terminal to the nominal voltage of the traction battery.

[0053] In one aspect of the present invention, the plurality of switches include: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first opening and closing of the third switch, the method further comprising, in response to no DC voltage being detected at the external charging terminal and the predetermined DC voltage being less than a nominal voltage of the traction battery: closing the third switch and the fourth switch; opening the first switch, the second switch, and the fifth switch; and operating the voltage converter to reduce a voltage from the traction battery to a predetermined DC voltage supplied to the external load terminal.

[0054] In one aspect of the present invention, the plurality of switches include: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch, the method further comprising: closing the fourth switch and the fifth switch; opening the first switch, the second switch, and the third switch; and disabling the voltage converter to provide an unregulated traction battery voltage to the external load terminal.

[0055] In one aspect of the invention, the plurality of switches include: a first switch between a first one of the external charge terminals and the traction battery; a second switch between the first external charge terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charge terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch, the method further comprising, in response to a DC voltage detected at the external charge terminal being within a predetermined range of the nominal traction battery voltage: closing the first switch, the fourth switch, and the fifth switch; opening the second switch and the third switch; and disabling the voltage converter to provide an unregulated voltage from the external charge terminal to the external load terminal.

[0056] According to the present invention, an electrified vehicle system is provided, having: a traction battery; a bidirectional synchronous DC / DC voltage converter; a plurality of switches configured to selectively connect at least one of the voltage converter and the traction battery to at least one of an external charging terminal and an external load terminal; and a controller programmed to operate the voltage converter in one of a disabled mode, a boost mode, and a buck mode based on which of the voltage converter, the traction battery, the external charging terminal, and the external load terminal is connected and in response to a voltage of the traction battery related to a voltage detected at the external charging terminal and a voltage supplied to the external load terminal.

[0057] According to an embodiment, the plurality of switches include: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first one of the external load terminals; a fourth switch between a second one of the external charging terminals and a second one of the external load terminals; and a fifth switch between the first switch and the third switch.

[0058] According to an embodiment, the controller is programmed to operate the plurality of switches and the voltage converter to simultaneously supply power from the external charging terminal to the traction battery and the external load terminal.

Claims

1. An electric vehicle comprising: an electric machine arranged to selectively provide propulsion torque to wheels of the electrified vehicle; a traction battery electrically coupled to the electric machine; Synchronous switching DC / DC voltage converter; a plurality of switches configured to selectively connect external charging terminals to the traction battery, the voltage converter, and external load terminals; as well as At least one controller programmed to selectively operate the voltage converter and control the plurality of switches to connect the external charge terminal to the voltage converter and the external load terminal based on a nominal voltage of the traction battery related to a voltage detected at the external charge terminal and a requested voltage supplied to the external load terminal.

2. The electrified vehicle of claim 1 , wherein the at least one controller is programmed to, in response to the voltage detected at the external charging terminal being a DC voltage within a predetermined range of the nominal voltage of the traction battery, controlling a first switch of the plurality of switches to connect at least one of the external charging terminals to the traction battery; and At least a second switch of the plurality of switches is controlled to disconnect at least one of the external load terminals from the voltage converter and the traction battery to charge the traction battery.

3. The electrified vehicle of claim 2, wherein the at least one controller is programmed to, in response to the voltage detected at the external charging terminal being a DC voltage outside the predetermined range of the nominal voltage of the traction battery and less than the nominal voltage, controlling the first of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery; controlling at least the second switch of the plurality of switches to connect at least one of the external load terminals to the voltage converter; as well as The voltage converter is controlled to increase the DC voltage from the external charging terminal to the nominal voltage of the traction battery to charge the traction battery.

4. The electrified vehicle of claim 1 , wherein the at least one controller is programmed to, in response to the requested voltage supplied to the external load terminal being a DC voltage less than the nominal voltage of the traction battery and the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery: controlling a first switch of the plurality of switches to connect at least one of the external charging terminals to the traction battery and a high voltage terminal of the voltage converter; controlling a second switch of the plurality of switches to disconnect at least one of the external charging terminals from a low voltage terminal of the voltage converter; controlling at least a third switch of the plurality of switches to connect the low voltage terminal of the voltage converter to the external charging terminal; as well as The voltage converter is controlled to reduce the DC voltage detected at the external charging terminal to the requested voltage supplied to the external load terminal.

5. The electrified vehicle of claim 1 , wherein the at least one controller is programmed to, in response to the requested voltage supplied to the external load terminal being a DC voltage less than the nominal voltage of the traction battery and the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery, control at least a fourth switch of the plurality of switches to disconnect the traction battery from the external load terminal.

6. The electrified vehicle of claim 1 , wherein the at least one controller is programmed to, in response to the requested voltage supplied to the external load terminal and the voltage detected at the external charging terminal being a DC voltage less than the nominal voltage of the traction battery: controlling a first switch of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery and the high voltage terminals of the voltage converter; controlling a second switch of the plurality of switches to connect at least one of the external charging terminals to a low voltage terminal of the voltage converter; controlling at least a third switch of the plurality of switches to connect at least one of the external charging terminals to at least one of the external load terminals; as well as The voltage converter is controlled to increase the DC voltage detected at the external charging terminal to the nominal voltage of the traction battery.

7. The electrified vehicle of claim 6 , wherein the at least one controller is further programmed to, in response to the requested voltage supplied to the external load terminal and the voltage detected at the external charging terminal being a DC voltage less than the nominal voltage of the traction battery, control at least a fourth switch of the plurality of switches to disconnect the traction battery from the external load terminal.

8. The electrified vehicle of claim 6, wherein the at least one controller is further programmed to, in response to the requested voltage supplied to the external load terminal and the voltage detected at the external charging terminal being a DC voltage less than the nominal voltage of the traction battery: controlling at least a fourth switch of the plurality of switches to connect the traction battery to the external load terminal; and At least a fifth switch of the plurality of switches is controlled to disconnect the low voltage terminal of the voltage converter from at least one of the external load terminals.

9. The electrified vehicle of claim 1 , wherein the at least one controller is programmed to, in response to the requested voltage supplied to the external load terminal being a DC voltage less than the nominal voltage of the traction battery: controlling a first switch of the plurality of switches to disconnect at least one of the external charging terminals from the traction battery and the high voltage terminals of the voltage converter; controlling a second switch of the plurality of switches to disconnect at least one of the external charging terminals from a low voltage terminal of the voltage converter; controlling at least a third switch of the plurality of switches to connect the low voltage terminal of the voltage converter to at least one of the external load terminals; controlling at least a fourth switch of the plurality of switches to disconnect the traction battery from at least one of the external load terminals; as well as The voltage converter is controlled to reduce the DC voltage from the traction battery to the requested voltage supplied to the external load terminals.

10. A method for controlling an electrified vehicle having: a traction battery; the traction battery electrically coupled to an electric machine; a synchronous DC / DC voltage converter; and a plurality of switches configured to selectively connect external charging terminals to the voltage converter, the traction battery, and external load terminals, the method comprising, by a vehicle controller based on a nominal voltage of the traction battery related to a DC voltage detected at the external charging terminals and a predetermined DC voltage delivered to the external load terminals: controlling the plurality of switches to selectively connect the external charging terminal, the voltage converter, and the external load terminal; as well as The voltage converter is controlled to operate to increase or decrease voltage based on which one or more of the voltage converter, the external charging terminal, the external load terminal, and the traction battery are connected via the plurality of switches.

11. The method of claim 10, wherein the plurality of switches comprises: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first external load terminal of the external load terminals; a fourth switch, the fourth switch being between a second external charging terminal among the external charging terminals and a second external load terminal among the external load terminals; as well as a fifth switch, the fifth switch being between the first switch and the third switch, The method further includes, in response to the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery: closing the first switch; Disconnecting the second switch, the third switch, the fourth switch, and the fifth switch; as well as Disable the voltage converter.

12. The method of claim 10, wherein the plurality of switches comprises: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first external load terminal of the external load terminals; a fourth switch, the fourth switch being between a second external charging terminal among the external charging terminals and a second external load terminal among the external load terminals; as well as a fifth switch, the fifth switch being between the first switch and the third switch, The method further includes, in response to the DC voltage detected at the external charging terminal being less than the nominal voltage of the traction battery: Disconnecting the first switch, the third switch, the fourth switch, and the fifth switch; closing the second switch; as well as The voltage converter is operated to increase the voltage from the external charging terminal to the nominal voltage of the traction battery.

13. The method of claim 10, wherein the plurality of switches comprises: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first external load terminal of the external load terminals; a fourth switch, the fourth switch being between a second external charging terminal among the external charging terminals and a second external load terminal among the external load terminals; as well as a fifth switch, the fifth switch being between the first switch and the third switch, The method further includes, in response to the DC voltage detected at the external charging terminal being within a predetermined range of the nominal voltage of the traction battery and the predetermined DC voltage being less than the nominal voltage of the traction battery: closing the first switch, the third switch, and the fourth switch; Disconnecting the second switch and the fifth switch; as well as The voltage converter is operated to reduce the voltage from the external charging terminal to the predetermined DC voltage.

14. The method of claim 10, wherein the plurality of switches comprises: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first external load terminal of the external load terminals; a fourth switch, the fourth switch being between a second external charging terminal among the external charging terminals and a second external load terminal among the external load terminals; as well as a fifth switch, the fifth switch being between the first switch and the third switch, The method further includes, in response to the DC voltage detected at the external charging terminal and the predetermined DC voltage both being less than the nominal voltage of the traction battery: closing the second switch, the third switch and the fourth switch; Disconnecting the first switch and the fifth switch; as well as The voltage converter is operated to increase the voltage from the external charging terminal to the nominal voltage of the traction battery.

15. The method of claim 10, wherein the plurality of switches comprises: a first switch between a first one of the external charging terminals and the traction battery; a second switch between the first external charging terminal and a low voltage terminal of the voltage converter; a third switch between the second switch and a first external load terminal of the external load terminals; a fourth switch, the fourth switch being between a second external charging terminal among the external charging terminals and a second external load terminal among the external load terminals; as well as a fifth switch, the fifth switch being between the first switch and the third switch, The method further includes, in response to an absence of a DC voltage detected at the external charging terminal and the predetermined DC voltage being less than the nominal voltage of the traction battery: closing the third switch and the fourth switch; Disconnecting the first switch, the second switch, and the fifth switch; as well as The voltage converter is operated to reduce voltage from the traction battery to the predetermined DC voltage supplied to the external load terminals.

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