System and method for controlling the charging and discharging of a battery assembly of a vehicle

Abstract

A system for controlling the charging and discharging of a battery assembly of a vehicle includes an output device and a power module including a charging circuit having a bidirectional AC / DC converter and a split-phase inverter connected to a common transformer. A controller is configured to control the power module according to at least one of several modes of operation, including a charging operation in which AC power charges the battery assembly via the charging circuit.The operating modes include a simultaneous charge and discharge operation in which the power module generates a split-phase voltage comprising a first AC voltage and a second AC voltage, the first AC voltage being phase-shifted from the second AC voltage, the first AC voltage being applied to charge the battery assembly and the second AC voltage being provided to an external system via the output device.

Description

INITIATIONThe invention relates to electric vehicles. More particularly, the invention relates to a system and method for controlling charging and discharging of a battery assembly of a vehicle.Vehicles including gasoline and diesel powered vehicles, as well as electric and hybrid electric vehicles, have a battery pack for purposes such as powering electric motors, electronics, and other vehicle subsystems. Such vehicles typically include multiple different modules for controlling aspects of the store. For example, some electric and hybrid vehicles include separate modules for powering electric motors and low voltage components. Some vehicles also include capabilities to provide alternating current (AC) power from vehicle battery systems.For further background information, reference is made at this point to the publications DE 10 2023 103 747 A1, DE 10 2022 127 651 A1 and DE 11 2019 006 788 T5.SUMMARYAccording to the invention, there is provided a system for controlling charging and discharging of a battery assembly of a vehicle, characterised by the features of claim 1.The system for controlling charging and discharging of a battery assembly of a vehicle includes an output device and a power module configured to be selectively connected to the output device and the battery assembly, the power module including a charging circuit having an AC / DC bidirectional converter (AC / DC converter) and a split-phase inverter, the charging circuit and the split-phase inverter being connected to a common transformer. A controller is configured to control the power module according to at least one of a plurality of modes, the plurality of modes including a charging mode in which AC power from a power source charges the battery array via the charging circuit. The plurality of modes includes a simultaneous charging and discharging operation in which the power module generates a split-phase voltage having a first AC voltage and a second AC voltage, the first AC voltage being out of phase with the second AC voltage, and the first AC voltage is applied to charge the battery assembly, and the second AC voltage is provided via the external system output device.In addition to the one or more features described herein, the charging circuit includes a primary DC / DC converter connected to the common transformer.In addition to the one or more features described herein, the common transformer is selectively connected to the battery assembly and / or to one or more low voltage components of the vehicle.In addition to the one or more features described herein, the common transformer is selectively connected to the battery array by a high voltage DC / DC converter configured to provide a high voltage to the battery array, and the common transformer is selectively connected to the one or more low voltage components by a low voltage DC / DC converter.In addition to the one or more features described herein, the split-phase inverter includes a group of switches in a half-bridge configuration.In addition to the one or more features described herein, the output device includes an integrated matching device configured to convert the second AC voltage to an output voltage that meets the voltage requirements of the output device.In addition to the one or more features described herein, the integrated matching device is configured to implement between 120 volts and 240 volts.In addition to the one or more features described herein, the power module is operated in charging operation by generating the first AC voltage having a first phase and the second AC voltage having a second phase, the first phase being equal to the second phase, and supplying the first and second AC voltages to the battery assembly.Furthermore, according to the invention, a method for controlling the charging and discharging of a battery arrangement of a vehicle is presented, which method is distinguished by the features of claim 8.The method for controlling charging and discharging of a battery assembly of a vehicle includes connecting an AC (Ac) power source to a power module configured to be selectively connected to an output device and the battery assembly, the power module including a charging circuit having a bidirectional AC / DC converter (AC / DC converter) and a split-phase inverter, the charging circuit and the split-phase inverter being connected to a common transformer. The method also includes providing AC power via an input voltage to the power module and performing charging of the battery array via the charging circuit and / or simultaneous charging of the battery array and discharging power to an external system. The external system is connected to the output device, and the charging and discharging includes generating, by the power module, a split-phase voltage, the split-phase voltage having a first AC voltage and a second AC voltage, the first AC voltage being out of phase with the second AC voltage, and the first AC voltage being applied to charge the battery array, and the second AC voltage being provided via the external system output device.In addition to the one or more features described herein, the charging circuit includes a primary DC / DC converter connected to the common transformer.In addition to the one or more features described herein, the common transformer is selectively connected to the battery assembly and / or to one or more low voltage components of the vehicle.In addition to the one or more features described herein, the method includes powering the one or more low voltage components, wherein the powering includes connecting the power module to a low voltage DC-DC converter.In addition to the one or more features described herein, the split-phase inverter includes a group of switches in a half-bridge configuration.In addition to the one or more features described herein, the output device includes an integrated matching device configured to convert the input voltage to an output voltage that corresponds to the voltage requirements of the output device.In addition to the one or more features described herein, the method includes powering the output device, wherein the powering includes connecting the output device to the AC power source and adjusting the input voltage through the integrated matching device.In addition to the one or more features described herein, charging the battery assembly includes generating the first AC voltage having a first phase and the second AC voltage having a second phase, the first phase being equal to the second phase, and supplying the first and second AC voltages to the battery assembly.According to yet another exemplary embodiment, a vehicle system includes a battery assembly and a charge and discharge system including a controller configured to perform a method. The method includes detecting connection of an AC (Ac) power source to a power module configured to be selectively connected to an output device and the battery array, the power module including a charging circuit having a bidirectional AC / DC (Ac / Dc) converter and a split-phase inverter, the charging circuit and the split-phase inverter being connected to a common transformer. The method also includes receiving AC power at an input voltage at the power module and performing charging of the battery array via the charging circuit and / or simultaneously charging the battery array and discharging power to an external system. The external system is connected to the output device, and the simultaneous charging and discharging includes generating, by the power module, a split-phase voltage, wherein the split-phase voltage has a first AC voltage and a second AC voltage, and wherein the first AC voltage is out of phase with the second AC voltage, and wherein the first AC voltage is applied to charge the battery array and the second AC voltage is provided via the external system output device.In addition to the one or more features described herein, the charging circuit includes a primary DC / DC converter connected to the common transformer, the common transformer being selectively connected to the battery assembly and / or one or more low voltage components of the vehicle.In addition to the one or more features described herein, the output device includes an integrated matching device configured to convert the input voltage to an output voltage that corresponds to the voltage requirements of the output device.In addition to the one or more features described herein, charging the battery assembly includes generating the first AC voltage having a first phase and the second AC voltage having a second phase, the first phase being equal to the second phase, and supplying the first and second AC voltages to the battery assembly.The above-described features and advantages and other features and advantages of the invention will become apparent from the following detailed description when taken in conjunction with the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGSOther features, advantages and details appear, by way of example only, in the following detailed description, the detailed description referring to the drawings, in which: FIG. 1 is a schematic diagram of an electric or hybrid vehicle in accordance with an exemplary embodiment; FIG. 2 is a circuit diagram illustrating a power module configured to control aspects of charging and discharging according to an example embodiment; FIG. 3 illustrates an example of split-phase AC voltage generated by the power module of FIG. 2 ; FIG. 4 illustrates an embodiment of a vehicle system according to an example embodiment; FIG. 5 illustrates a typical vehicle system including components for powering low voltage loads; and FIG. 6 illustrates a computer system for performing aspects of charging and discharging, according to an example embodiment.DETAILED DESCRIPTIONThe following description is merely exemplary in nature. It should be understood that throughout the drawings, corresponding reference numerals designate similar or corresponding portions and features. As used herein, the term module refers to processing circuitry that may include an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) having memory executing one or more software or firmware programs, combinatorial logic circuitry, and / or other suitable components that provide the described functionality.According to example embodiments, methods, apparatus, and systems are provided to enable charging and discharging of battery assemblies and battery systems, such as vehicle battery assemblies. One embodiment of a battery charging system includes a power module that includes an AC / DC converter (AC / DC converter) and a split-phase converter. The power module is controllable to generate a split-phase voltage having two AC voltages that may be in-phase or out-of-phase. The power module may be used to control charging of a battery system (e.g., a vehicle battery pack) and power external loads (e.g., AC loads).The power module may also be used to simultaneously charge the battery system while powering one or more external loads. According to an embodiment, the power module is configured to split an input voltage (e.g., from an electrical grid or an AC charger) into separate AC voltages that are phase shifted (e.g., 180 degrees separated). One of the voltages is provided to the battery system to charge it, and another of the voltages is provided to an external load via one or more output devices. Each output device may include an integrated matching device for providing different voltage levels (e.g., 120 and 240 volts).Embodiments described herein provide numerous advantages and technical effects. The embodiments provide a discharge and charging capability that includes simultaneous charging and discharging (e.g., charging of a battery system during power supply of a network or an external device or system) without the need for additional circuitry. The functionality described here is therefore achievable with fewer components than in conventional systems.For example, an on-board charging device having the capabilities described herein may be provided that may generate split-phase voltage and perform simultaneous charging and discharging without a decrease in charging power as well as without any additional circuitry (compared to known on-board charging modules (OBCM)). Embodiments provide a single module or device that can provide vehicle charging power and split-phase power (compared to known systems using a separate OBCM module and a split-phase power module).The split-phase voltage is achieved in part by AC / DC conversion circuitry and in part by a split-phase inverter stage that can be used to provide additional charging power when split-phase loads are not connected. Power modules described herein may be used for vehicle-to-grid applications and for vehicle-to-house applications, as well as any other applications for supplying power to external AC loads without the need for a separate module for providing split-phase power.The embodiments are not limited to use with a specific vehicle or device or system using battery assemblies, and may be applicable to various contexts. For example, embodiments may be used with automobiles, trucks, aircraft, worksite equipment, agricultural equipment, automated factory equipment, and / or other apparatus or system that may use high voltage battery packs or other battery assemblies.FIG. 1 shows an embodiment of a motor vehicle 10 including a vehicle body 12 at least partially defining a passenger compartment 14. The vehicle body 12 also supports various vehicle subsystems including a propulsion system 16 and other subsystems to assist functions of the propulsion system 16, and other vehicle components such as a brake subsystem, a suspension system, a steering subsystem, a fuel injection subsystem, an exhaust subsystem, and others.The vehicle 10 may be an engine vehicle, an electrically driven vehicle (EV), or a hybrid vehicle. In one embodiment, the vehicle 10 is a hybrid vehicle that includes an engine system 18 and at least one electric motor assembly. In one embodiment, propulsion system 16 includes an electric motor 20 and may include one or more additional motors positioned at various locations. The vehicle 10 may be a fully electric vehicle having one or more electric motors.The vehicle 10 includes a battery system 22 that may be electrically connected to the engine 20 and / or other components such as vehicle electronics. The battery system 22 may be configured as a rechargeable energy storage system (RESS). In one embodiment, the battery system 22 includes a battery assembly, such as a high voltage battery pack 24, having a plurality of battery modules 26. The battery system 22 may also include a monitoring unit 28 that includes components such as a processor, memory, interface, bus, and / or other suitable components.Each battery module includes a plurality of cells (not shown) having a selected chemical composition. In one embodiment, each cell is a lithium ion battery, such as a lithium iron phosphate (LFP) battery or a lithium nickel manganese cobalt oxide (NKM) battery. The battery pack 24 is not so limited and may have any suitable chemical composition. Further examples include the chemical compositions nickel-metal hydride and lead acid.The battery system 22 is electrically connected to components of the propulsion system 16. The propulsion system also includes an inverter module 30 and a DC-DC converter module 32. the inverter module 30 (e.g., a tractive power inverter unit or a TPIM) converts DC (DC) power from the battery system 22 to polyphase AC (polyphase AC) power (e.g., three phase AC power, six phase AC power, etc.) to drive the motor 20.Various control modules (electronic control modules or ECUs) may be included in the vehicle 10. According to one embodiment, the vehicle 10 includes an integrated power module 40 configured to control aspects of charging the battery pack 24 and discharging the battery pack to supply power to an external system, such as a power grid. The power module 40 is selectively connected to a bidirectional charge port 42 and one or more output devices 44. It should be appreciated that embodiments are not limited to the number or location of output devices shown, as any number of output devices may be present at desired locations in the vehicle.The vehicle 10 also includes a computer system 50 that includes one or more processing devices 52 and a user interface 54. The various processing devices and processing units may communicate with each other via a communication device or a communication system such as a controller area network (CAN) or a transmission control protocol (TCP) bus.FIG. 2 shows an embodiment of power module 40 as well as connections between power module 40 and other components of vehicle 10.The DC bus 64 is connected to a primary DC / DC converter 66 (primary stage). The primary DC / DC converter 66 is connected to a secondary DC / DC converter 68 (secondary stage) and the battery pack 24 via a transformer 70.The inverter 62 is, according to one embodiment, a half bridge converter stage that operates in cooperation with the AC / DC converter 60 to generate a split voltage in the form of two independent AC voltages. The two voltages may be in-phase (e.g., during the exclusive charging of the battery pack 24) or out-of-phase (e.g., during the simultaneous charging of the battery pack 24 and powering an external load). For example, as shown in FIG. 2, the inverter 62 includes a pair of switches 72 in a half bridge and a group of capacitors 74.When the charging terminal 42 or an output device 44 is connected to an AC power source (represented by phase currents 76) such as a grid or a generator, the power module 40 may be used to charge the battery pack 24 and / or provide power to one or more external loads. As discussed herein, the power module 40 may be used exclusively to charge the battery pack 24 (e.g., function as OBCM) by providing both voltages of a split-phase voltage to the battery pack 24. The power module 40 may also be used to simultaneously charge the battery pack 24 and provide power to external loads by providing a portion of the split voltage to the battery pack 24 and another portion of the split voltage to one or more external loads.Also shown in FIG. 2 is an embodiment of one or more output devices 44 that may be used to facilitate receiving AC power or supplying AC power. According to this embodiment, each dispenser 44 includes a connection port 78 integral with a matching device 80. The matching device 80 is provided to convert an input or output voltage to match the voltage of an AC power or the voltage requirements of an external load.For example, each matching device 80 is configured to translate between 240 volts (V) and 120 V, with a dedicated matching device 80 provided for each output device 44. This distributed configuration significantly reduces the size of the 240V / 120V conversion components compared to known systems.The matching devices 80 may be powered from any suitable source such as the battery pack 24, a low voltage battery, or an external power source. For example, each adjuster 80 is connected to one or more switches, such as a relay 82, which may be controlled to selectively provide power to the output devices 44. The power module 40 includes or is connected to one or more other switching devices, such as a relay 88, to selectively connect the inverter 62 to the outputs 44.For example, if the input voltage of the power source (current or currents 76) meets the power requirements of the output devices (e.g., 120V), the input voltage is directly connected to the outputs 44. If the input voltage is not suitable (e.g., if the input voltage is 240 V), each adjuster 80 is used, if necessary, to step down or otherwise adjust the input voltage. A voltage sensor 86 may be included to determine whether a voltage adjustment is desired.The power module 40 is controllable by any suitable processing device or system referred to as a controller 84. The controller may be an already existing controller or a dedicated controller.The power module 40 is controlled to operate in one or more modes. The modes may include a charge mode, a discharge mode, and a simultaneous charge and discharge mode.The various modes of operation and the one or more corresponding methods for controlling power transfer are described below. The modes include a charging mode to provide charge to the battery pack 24 and a discharging mode to power other components or loads including external loads (e.g., an electrical grid or residential loads) from the battery pack 24.The modes also include a simultaneous charging and discharging operation in which the power module 40 is operated to provide a split-phase voltage that is used to charge the battery pack 24 while simultaneously providing power to one or more external loads.In these modes, the relay 88 is closed to connect the inverter 62 to the load 76 and the output devices 44. The input voltage (e.g., the 120 V or 240 V line voltage) generates one portion of the AC voltage required for the split phase, while the inverter 62 generates the other portion of the AC voltage.In the charging operation, the relay 82 is opened and both pieces of split-phase voltage are provided for charging to the battery pack 24. Both parts are in phase.In the simultaneous charging and discharging operation, the inverter 62 shifts one of the pieces of split-phase voltage. An example of the split-phase voltage is shown in FIG. 3, which shows a graph 90 of the voltage V as a function of time t. In this example, the line voltage is 120 V, the power module 40 generates a first AC voltage 92 from the line voltage, and the inverter 62 generates a second AC voltage 94 that is 180 degrees apart from the first AC voltage 92.Embodiments may be used to charge a high voltage battery system such as the battery pack 24 and / or charge low voltage devices. A "high voltage" refers to a voltage sufficient to power the battery pack, and may be 400 V, 800 V, or any other suitable voltage. A "low voltage" refers to a voltage sufficient to supply other components with an operating voltage that is lower than the high voltage. For example, a low voltage may be 12 V, 24 V, or another suitable voltage for powering components such as electronics in the vehicle 10. Low and high are used as relative terms and are not intended to refer to a particular voltage level.According to one embodiment, power module 40 may be used to control the power supply of low voltage components. In this embodiment, the power module 40 performs functions related to supplying power to low voltage components. Therefore, the power module 40 can replace existing modules such as an auxiliary power module (APM).For example, as shown in FIG. 2, the vehicle 10 (FIG. 1 ) includes a low voltage DC / DC converter 96 configured to step down a received voltage to power low voltage loads 98. The power module 40 may be placed in a charging mode in which a portion of the split-phase voltage is provided to the DC / DC converter 96.FIG. 4 shows an example of a configuration of the power module 40 and the connections to the battery pack 24 and the low voltage loads 98. as shown, the charging of the battery pack 24 and the charging of low voltage components may be achieved using a single primary DC / DC stage (i.e., the DC / DC converter 66).FIG. 5 shows an example of a configuration of a low voltage charging system 100 in a general electric or hybrid vehicle. The system 100 includes an AC / DC conversion stage 102 and a transformer (not shown) that connects a primary DC / DC stage 104 and a secondary DC / DC stage 106 to the battery pack 24. To power the low voltage components 98, a separate transformer connecting the primary and secondary stages 108 and 110 is provided.As shown in FIGS. 4 and 5, power module 40 reduces the number of components needed to charge both high and low voltage components. The power module 40 uses a common transformer and therefore only a primary stage that can be used for both high and low voltages.FIG. 6 illustrates aspects of an embodiment of a computer system 140 that may perform various aspects of embodiments described herein. The computer system 140 includes at least one processing device 142 that generally includes one or more processors for performing aspects of image acquisition and analysis methods described herein.Components of computer system 140 include processing device 142 (such as one or more processors or processing units), memory 144, and bus 146 that couples various system components including system memory 144 to processing device 142. System memory 144 may include a plurality of computer system readable media. Such media may be any available media accessible by the processing device 142, and includes both volatile and non-volatile media and removable and non-removable media.For example, system memory 144 includes non-volatile memory 148, such as a hard disk, and may also include volatile memory 150, such as random access memory (RAM) and / or cache. Computer system 140 may further include other removable / non-removable volatile / non-volatile computer system storage media.System memory 144 may include at least one program product having a set (e.g., at least one) of program modules configured to perform functions of the embodiments described herein. For example, system memory 144 stores various program modules that generally perform the functions and / or methodologies of embodiments described herein. A module or modules 152 may be included to perform functions related to monitoring and performing load and unload operations described herein. The system 140 is not so limited as further modules may be included. As used herein, the term module refers to processing circuitry that may include an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) having memory executing one or more software or firmware programs, combinatorial logic circuitry, and / or other suitable components that provide the described functionality.The processing device 142 may also communicate with one or more external devices 156, such as a keyboard, a pointing device, and / or any devices (e.g., a network card, a modem, etc.) that enable the processing device 142 to communicate with one or more other computing devices. Communication with various devices may be via input / output (I / O) interfaces 164 and 165.The processing device 142 may also communicate with one or more networks 166, such as a local area network (LAN), a general wide area network (WAN), a bus network, and / or a public network (e.g., the Internet), via a network adapter 168. It should be understood that other hardware and / or software components may be used in conjunction with computer system 40, although not shown. Examples include, but are not limited to, microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, and data archive storage systems, etc.

Claims

A system for controlling charging and discharging of a battery assembly (24) of a vehicle (10), comprising: an output device (44); a power module (40) configured to be selectively connected to the output device (44) and the battery assembly (24), wherein the power module (40) includes charging circuitry having a bidirectional AC / DC converter (AC / DC converter) (60) and a split-phase inverter (62), and wherein the charging circuitry and the split-phase inverter (62) are connected to a common transformer (70); and a controller (84) configured to control the power module (40) according to at least one of a plurality of modes, the plurality of modes comprising: a charging mode in which AC power from a power source charges the battery array (24) via the charging circuit; and a simultaneous charging and discharging mode in which the power module (40) generates a split-phase voltage having a first AC voltage and a second AC voltage, wherein the first AC voltage is out of phase with the second AC voltage, and wherein the first AC voltage is applied to charge the battery array (24), and the second AC voltage is provided to an external system via the output device (44).The system of claim 1, wherein the charging circuit includes a primary DC / DC converter (66) connected to the common transformer (70).The system of claim 2, wherein the common transformer (70) is selectively connected to the battery assembly (24) and / or to one or more low voltage components (98) of the vehicle (10).The system of claim 3, wherein the common transformer (70) is selectively connected to the battery assembly (24) through a high voltage DC / DC converter configured to provide a high voltage to the battery assembly (24), and the common transformer (70) is selectively connected to the one or more low voltage components (98) through a low voltage DC / DC converter (96).The system of claim 1, wherein the split-phase inverter (62) includes a group of switches in a half-bridge configuration.The system of claim 1, wherein the output device (44) includes an integrated matching device (80) configured to convert the second AC voltage to an output voltage that corresponds to the voltage requirements of the output device (44).The system of claim 1, wherein the power module (40) is operated in the charging mode by generating the first AC voltage having a first phase and the second AC voltage having a second phase, the first phase being equal to the second phase, and supplying the first AC voltage and the second AC voltage to the battery assembly (24).A method of controlling charging and discharging of a battery assembly (24) of a vehicle (10), comprising: connecting an AC power source (AC power source) to a power module (40) configured to be selectively connected to an output device (44) and the battery assembly (24), the power module (40) including a charging circuit having a bidirectional AC / DC converter (AC / DC converter) (60) and a split-phase inverter (62), the charging circuit and the split-phase inverter (62) being connected to a common transformer (70); providing AC power at an input voltage to the power module (40); and performing: charging the battery assembly (24) via the charging circuit; and / or simultaneous charging of the battery assembly (24) and discharging power to an external system, the external system connected to the output device (44), wherein the simultaneous charging and discharging comprises generating a split-phase voltage by the power module (40), wherein the split-phase voltage has a first AC voltage and a second AC voltage, wherein the first AC voltage is out of phase with the second AC voltage, and wherein the first AC voltage is applied to charge the battery assembly (24), and the second AC voltage is provided to the external system via the output device (44).The method of claim 8, wherein the charging circuit includes a primary DC-DC converter (66) connected to the common transformer (70), the common transformer (70) being selectively connected to one or more low voltage components (98) of the vehicle (10), the method further comprising powering the one or more low voltage components (98), and wherein powering comprises connecting the power module (40) to a low voltage DC converter.The method of claim 8, wherein the output device (44) includes an integrated matching device (80) configured to convert the input voltage to an output voltage that meets the voltage requirements of the output device (44), and wherein the method further comprises powering the output device (44), wherein the powering comprises connecting the output device (44) to the AC power source and adjusting the input voltage by the integrated matching device (80).

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