Apparatus for thermal control of a battery system and method of thermally controlling a battery system of a vehicle

Abstract

An apparatus for thermal control of a battery system includes a heating control module electrically connected to the battery system and a conversion device configured to control power output from the battery system. The heating control module is configured to measure a current through the conversion device, the measured current being provided by a battery system of a vehicle during vehicle operation or by an energy source during vehicle charging. The heating control module is further configured to control the conversion device to generate an alternating current (AC) heating current using the measured current and to apply the AC heating current to the battery system to heat the battery system to a desired temperature.

Description

Technical Field

[0001] This disclosure relates to thermal control of batteries, and more specifically, to heating battery assemblies or systems using an applied current. Background Technology

[0002] Vehicles, including gasoline and diesel-powered vehicles, as well as electric and hybrid vehicles, are characterized by battery storage for purposes such as powering electric motors, electronic devices, and other vehicle subsystems. Maintaining appropriate operating temperatures in low-temperature environments can be challenging. For example, battery charging may become limited at low temperatures. Therefore, it is desirable to provide a device or system capable of providing battery capacity under a variety of low-temperature conditions. Summary of the Invention

[0003] In one exemplary embodiment, an apparatus for thermal control of a battery system includes a heating control module electrically connected to the battery system and a conversion device configured to control power output from the battery system. The heating control module is configured to measure a current passing through the conversion device, the measured current being provided by the vehicle's battery system during vehicle operation or by an energy source during vehicle charging. The heating control module is also configured to control the conversion device to generate an alternating current (AC) heating current using the measured current and to apply the AC heating current to the battery system to heat the battery system to a desired temperature.

[0004] In addition to one or more features described herein, the vehicle includes a first electric motor connected to a first inverter and a second electric motor connected to a second inverter.

[0005] In addition to one or more features described herein, the control conversion device includes controlling the phase pins of the first inverter to generate AC heating current.

[0006] In addition to one or more features described herein, the phase pin includes a quasi-resonant circuit (QRC) with an inductor, a capacitor, and a half-bridge switch configuration, and controlling the phase pin includes controlling the QRC to generate AC heating current.

[0007] In addition to one or more features described herein, the first electric motor and battery system provide a measured current during vehicle operation and when the electric motor is idle.

[0008] In addition to one or more of the features described herein, the measured current is supplied by an energy source during charging.

[0009] In addition to one or more features described herein, the control conversion device includes electrically connecting an energy source to a phase pin of a first inverter or a phase pin of a second inverter.

[0010] In addition to one or more features described herein, the conversion device is a DC-DC converter, and controlling the conversion device includes controlling the DC-DC converter to generate the AC heating current when the first electric motor is idle.

[0011] In addition to one or more features described herein, the conversion device is a DC-DC converter, and controlling the conversion device includes controlling the DC-DC converter to generate the AC heating current using energy supplied by the energy source and the battery system when the vehicle is being charged.

[0012] In another exemplary embodiment, a method for thermally controlling a vehicle's battery system includes measuring a current through a conversion device configured to control power output from the battery system, the measured current being provided by the vehicle's battery system during vehicle operation or by an energy source during vehicle charging. The method also includes controlling the conversion device via a heating control module to generate an alternating current (AC) heating current using the measured current, and applying the AC heating current to the battery system to heat the battery system to a desired temperature.

[0013] In addition to one or more features described herein, the vehicle includes a first electric motor connected to a first inverter and a second electric motor connected to a second inverter, and wherein the control switching device includes controlling the phase pins of the first inverter to generate AC heating current.

[0014] In addition to one or more features described herein, the phase pin includes a quasi-resonant circuit (QRC) with an inductor, a capacitor, and a half-bridge switch configuration, and controlling the phase pin includes controlling the QRC to generate AC heating current.

[0015] In addition to one or more features described herein, when the electric motor is idle, the first electric motor and battery system provide the measured current.

[0016] In addition to one or more of the features described herein, the measured current is supplied by an energy source during charging.

[0017] In addition to one or more features described herein, the conversion device is a DC-DC converter, and controlling the conversion device includes controlling the DC-DC converter to generate the AC heating current when the first electric motor is idle.

[0018] In addition to one or more features described herein, the conversion device is a DC-DC converter, and controlling the conversion device includes controlling the DC-DC converter to generate the AC heating current using energy supplied by the energy source and the battery system when the vehicle is being charged.

[0019] In yet another exemplary embodiment, the vehicle system includes a memory having computer-readable instructions and a processing means for executing the computer-readable instructions, which control the processing means to perform a method. The method includes measuring a current through a conversion device configured to control power output from a battery system, the measured current being provided by the vehicle's battery system during vehicle operation or by an energy source during vehicle charging. The method also includes controlling the conversion device to generate an alternating current (AC) heating current using the measured current, and applying the AC heating current to the battery system to heat the battery system to a desired temperature.

[0020] In addition to one or more features described herein, the vehicle includes a first electric motor connected to a first inverter and a second electric motor connected to a second inverter, and wherein the control switching device includes controlling the phase pins of the first inverter to generate AC heating current.

[0021] In addition to one or more features described herein, the conversion device is a DC-DC converter, and controlling the conversion device includes controlling the DC-DC converter to generate the AC heating current when the electric motor is idle.

[0022] In addition to one or more features described herein, the conversion device is a DC-DC converter, and controlling the conversion device includes controlling the DC-DC converter to generate the AC heating current using energy supplied by the energy source and the battery system when the vehicle is being charged.

[0023] The above-described features and advantages, as well as other features and advantages of this disclosure, will become apparent when taken in conjunction with the accompanying drawings and the following detailed description. Attached Figure Description

[0024] Other features, advantages, and details appear by way of example only in the following detailed specification, which refers to the accompanying drawings, wherein:

[0025] Figure 1 This is a top view of a motor vehicle including a battery assembly or system and a battery thermal management system according to an exemplary embodiment;

[0026] Figure 2 A portion of a dual-motor propulsion system according to an exemplary embodiment is depicted, including components used by a battery heating system;

[0027] Figure 3 A first inverter and a second inverter, configured according to an exemplary embodiment, are depicted as serving as part of a battery heating system to apply heating current to a battery assembly or system.

[0028] Figure 4A first inverter and a second inverter according to an exemplary embodiment are depicted, the first inverter and the second inverter being configured to apply a heating current to a battery assembly or system during charging of a battery system;

[0029] Figure 5 This schematically illustrates the use of an idle electric motor to heat a battery assembly or system according to an exemplary embodiment. Figure 3 The operation of the first inverter;

[0030] Figure 6 Depicting the process during operation Figure 3 and Figure 5 An example of the components of the first inverter used to heat the current of the battery system;

[0031] Figure 7 The illustration schematically shows, according to an exemplary embodiment, Figure 4 The first inverter heats the battery pack or system during charging.

[0032] Figure 8 Depicting the process during operation Figure 4 and Figure 7 An example of the components of the first inverter used to heat the current of the battery system;

[0033] Figure 9 A DC-DC converter according to an exemplary embodiment is depicted, configured to be used as part of a battery heating system to apply a heating current to the battery assembly or system during vehicle operation and / or during charging of the battery system;

[0034] Figure 10 The illustration schematically shows, according to an exemplary embodiment, Figure 9 The DC-DC converter heats the battery assembly or system during vehicle operation using an idle electric motor;

[0035] Figure 11 It is a flowchart depicting various aspects of a method for heating a battery assembly or system according to an exemplary embodiment;

[0036] Figure 12 These are flowcharts depicting various aspects of a method for heating a battery assembly or system according to exemplary embodiments; and

[0037] Figure 13 A computer system according to an exemplary embodiment is described. Detailed Implementation

[0038] The following description is exemplary in nature only and is not intended to limit this disclosure, its application, or use. It should be understood that throughout the drawings, corresponding reference numerals denote the same or corresponding parts and features.

[0039] According to exemplary embodiments, methods, apparatus, and systems for thermal control of battery components and battery systems, such as vehicle battery components or systems, are provided. Embodiments of the battery heating system are configured to heat or raise the temperature of the battery system (e.g., a battery pack) by applying alternating current (AC current) to the battery system. The AC current is applied using an electric motor in the vehicle during vehicle operation (e.g., during vehicle movement or when the vehicle is stationary), and / or using an energy source such as a charging station during battery charging.

[0040] In one embodiment, the vehicle is a dual-motor or multi-motor system propelled by two or more electric motors. The heating system uses energy supplied by the idle motor (i.e., the motor that does not produce torque) to modulate the current from the idle motor to generate AC heating current by controlling an inverter connected to the idle motor or a DC-DC converter in the vehicle. In another embodiment, the heating system controls an inverter or DC-DC converter to modulate the current from a charging station to generate AC heating current.

[0041] The embodiments described herein present numerous advantages and technical effects. The embodiments provide uniform and controllable heating of battery packs or systems using existing vehicle components. The embodiments provide efficient heating in low-temperature environments (e.g., below 25 degrees Celsius). In such environments, heat generation is typically inefficient, leading to negative range effects and performance degradation. Furthermore, DC fast charging (DCFC) power may be limited at low temperatures. The embodiments provide solutions to the aforementioned problems while also avoiding the need for additional components or auxiliary heating devices (e.g., PTC heaters). Moreover, the embodiments are more efficient than other heating devices.

[0042] The embodiments are not limited to use with any particular vehicle and can be applied to a variety of contexts. For example, the embodiments can be used with automobiles, trucks, aircraft, construction equipment, farm equipment, automated factory equipment, and / or any other device or system that may require additional thermal control to enhance the existing thermal control capabilities or features of the device or system.

[0043] Figure 1 An embodiment of a motor vehicle 10 is shown, which includes a body 12 that at least partially defines a passenger compartment 14. The body 12 also supports various vehicle subsystems, including a propulsion system 16, as well as other subsystems for supporting the functions of the propulsion system 16 and other vehicle components, such as a braking subsystem, a suspension system, a steering subsystem, a fuel injection subsystem, an exhaust subsystem, etc.

[0044] Vehicle 10 may be an internal combustion engine vehicle, an electric vehicle (EV), or a hybrid vehicle. In one embodiment, vehicle 10 is a hybrid vehicle that includes an internal combustion engine assembly 18 and at least one electric motor assembly. For example, propulsion system 16 includes a first electric motor 20 and a second electric motor 21. Motors 20 and 21 may be configured to drive wheels on opposite sides of vehicle 10. Any number of motors positioned at various locations may be used.

[0045] Vehicle 10 includes a battery system 22, which can be electrically connected to motors 20 and 21 and / or other components, such as vehicle electronics. Battery system 22 can be configured as a rechargeable energy storage system (RESS).

[0046] In one embodiment, the battery system 22 includes a battery assembly, such as a high-voltage battery pack 24 having multiple battery modules 26. Each battery module 26 includes multiple individual battery cells (not shown). The battery system 22 may also include a monitoring unit 28 configured to receive measurement results from sensors 30. Each sensor 30 may be an assembly or system having one or more sensors for measuring various battery and environmental parameters, such as temperature, current, and voltage. The monitoring unit 28 includes components such as a processor, memory, interface, bus, and / or other suitable components.

[0047] Battery system 22 is electrically connected to DC-DC converter module 32 and inverter module 34. Inverter module 34 (e.g., traction power inverter unit or TPIM) converts direct current (DC) power from the battery assembly into three-phase alternating current (AC) power to drive the motor. In an embodiment, inverter module 34 includes a first inverter 36 connected to motor 20 and a second inverter 38 connected to motor 21.

[0048] Battery system 22 can also be connected to other vehicle components or systems. For example, battery system 22 is connected to auxiliary power module (APM) 40, which controls the power output to components such as heating systems. APM 40 can be used to supply power from battery system 22 to heat passenger compartment 14.

[0049] Vehicle 10 may include a charging system that can be used to charge battery pack 24 and / or to supply power from battery pack 24 to charge another energy storage system (e.g., vehicle-to-vehicle charging). The charging system includes an onboard charging module (OBCM) 42 electrically connected to charging port 44.

[0050] The vehicle 10 also includes a computer system 48, which includes one or more processing units 50 and a user interface 52. The various processing units and units can communicate with each other via communication devices or systems such as Controller Area Network (CAN) or Transmission Control Protocol (TCP) bus.

[0051] Vehicle components form all or part of the heating system 60, which is configured to generate an alternating current (AC) signal (also referred to as "AC current," "heating current," or "AC heating current") and apply the AC current signal to the battery pack 24. The heating system 60 can be used to heat the battery pack 24 during vehicle movement, when the vehicle is operating and stationary, and / or during vehicle charging.

[0052] In one embodiment, the heating system 60 is configured to use energy generated by the battery pack 24 and the electric motor and / or charging station (or other energy source) to apply an AC heating current to the battery pack 24 by controlling a conversion device (e.g., an inverter and / or a DC-DC converter). The AC heating current can be generated by controlling components of the conversion device as a quasi-resonant circuit (QRC).

[0053] During the movement of a vehicle with a multi-motor architecture (i.e., having multiple electric motors for propulsion), one or more of the electric motors may have significant idle times. An electric motor is idle when it rotates but does not produce any torque (or any significant amount of torque), or, if such a clutch is available, the electric motor is disengaged from the axle. In one embodiment, the heating system 60 is configured to generate AC current by controlling the phase pin of the corresponding inverter (idle inverter), using the energy generated by the idle motor during driving (or stationary) to generate the AC heating current. In another embodiment, the system 60 utilizes energy from a charging station or other energy source during charging by connecting the idle inverter to the charging system and generating AC current in the idle inverter.

[0054] In one embodiment, the heating system 60 is configured to use energy from an idle electric motor or from an energy source (during charging) and generate an AC heating current via a DC-DC converter. The DC-DC converter may be a DC-DC converter module 32 in the vehicle 10 or another DC-DC converter. For example, during vehicle movement (or when the vehicle is idle), the DC-DC converter module 32 is electrically connected to an idle inverter, and the current is converted into an AC current signal by controlling the DC-DC converter module 32. In another example, during charging, the DC-DC converter module 32 is connected to the battery assembly 22, and the DC-DC converter module 32 is controlled to generate an AC heating current.

[0055] The heating system 60 includes a heating control module 62 configured to control various aspects of heating, including controlling switches in an inverter (e.g., inverter 36 or inverter 38) or DC-DC converter (e.g., DC-DC converter module 32) to connect and disconnect the conversion device, and controlling a conversion circuit (e.g., as a QRC) to generate heating current. The control module 62 may be a dedicated controller installed in the vehicle 10, or it may be an existing controller such as monitoring unit 28, OCBM 42, APM 40, or computer system 48. The heating control module 62 (also referred to as a “controller”) may also be implemented using a combination of controllers.

[0056] Figure 2 A dual-motor propulsion system is depicted, including components of an embodiment of a heating system 60. The propulsion system includes a first inverter 36 coupled to motor 20 and a second inverter 38 coupled to motor 21. Components of inverter 36 and / or inverter 38 serve as part of the heating system 60 and are controlled by controller 62. As further discussed herein, when vehicle 10 is in motion and the first motor 20 is idle, the first inverter 36 can be controlled to provide AC current heating, and the second motor 21 and the second inverter 38 can be used simultaneously for propulsion. Although the first inverter 36 is discussed as a heating inverter, the function of the inverter can be reversed as needed.

[0057] In this embodiment, the first inverter 36 and the second inverter 38 are three-phase inverters connected to the battery pack 24 via a DC drive bus 64. The first inverter 36 includes three sets of switches connected in parallel to each other and connected to the battery pack 24 and the motor 20. Each set of switches is in a half-bridge configuration. The first set of switches 66 and 68 is connected to the first motor phase (phase A), the second set of switches 70 and 72 is connected to the second motor phase (phase B), and the third set of switches 74 and 76 is connected to the third motor phase (phase C). A capacitor 78 is connected in parallel to the switch sets to filter current ripple.

[0058] The second inverter 38 also includes three sets of switches in a half-bridge configuration connected to the motor 21. The first set of switches 80 and 82 are connected to the first motor phase (phase A), the second set of switches 84 and 86 are connected to the second motor phase (phase B), and the third set of switches 88 and 90 are connected to the third motor phase (phase C). A capacitor 92 is connected in parallel to the switch sets.

[0059] Any suitable device can be used as a switch. For example, switches can include solid-state relays and transistors such as silicon (Si) insulated-gate bipolar transistors (IGBTs) and field-effect transistors (FETs). Examples of FETs include metal-oxide-semiconductor FETs (MOSFETs), Si MOSFETs, silicon carbide (SiC) MOSFETs, gallium nitride (GaN) high electron mobility transistors (HEMTs), and SiC junction-gate FETs (JFETs). Other examples of switches that can be used include power switching devices based on diamond, gallium oxide, and other wide-bandgap (WBG) semiconductors.

[0060] Figure 3 An embodiment of a heating system 60 is depicted, which includes components for promoting battery heating during vehicle movement (or otherwise during vehicle operation) when the motor is idle. A first inverter 36 is connected to the battery pack 24 via a switch 94 (S11) that connects the positive terminal of the battery pack 24 to the positive bus 96 (DC1+) and a switch 98 (S21) that connects the negative terminal of the battery pack to the negative bus 100 (DC1-).

[0061] As further discussed herein, the first inverter 36 can be selectively disconnected from the DC drive bus 64, allowing the first inverter 36 to be controlled to apply AC heating current. Simultaneously, the second inverter 38 can remain engaged with the DC drive bus 64 to provide drive. Similarly, the second inverter 38 can be selectively disconnected for heating, and the first inverter 36 can remain engaged to provide drive.

[0062] To selectively disconnect the first inverter 36 from the DC drive bus 64, switch 102 and inductor 104 (L1) are connected between the positive terminal and leg of inverter 36. When switch 102 is closed (on), diode 106 (D1) combined with inductor 104 provides isolation for inverter 36. As shown, switch 102 and inductor 104 can be connected to the A-phase leg of inverter 36 or to any other leg. A precharger 107 may be included to limit inrush current.

[0063] The second inverter 38 is connected to the drive bus 64 via diode 108 (D2). The second inverter 38 includes a switch 110 (S21) that connects the positive terminal of the battery pack 24 to the positive bus 112 (DC2+), and a switch 114 (S22) that connects the negative terminal of the battery pack to the negative bus 116 (DC2-). The second inverter 38 also includes a switch 118 (Sw2) and an inductor 120 (L2) connected between the positive terminal and the leg of the inverter 38.

[0064] If the first motor 20 is idle (e.g., during vehicle movement), the first inverter 36 can enter a heating mode, in which it is disconnected from the DC propulsion bus 64 and used for heating. Simultaneously, the second inverter 38 enters (or remains in) a propulsion mode, in which it is engaged with the DC propulsion bus 64 and used for propulsion. If the second motor 21 is idle, the second inverter 38 can enter a heating mode, while the first inverter 36 remains in propulsion mode.

[0065] When the first inverter 36 is in heating mode, switch 94 (S11) is open, and switches 102 (Sw1) and 98 (S21) are closed. In push mode, switches 94 (S11) and 98 (S21) are closed, and switch 102 (Sw1) is open.

[0066] Similarly, when the second inverter 38 is in heating mode, switch 110 (S21) is open, and switches 118 (Sw2) and 114 (S22) are closed. In push mode, switches 110 (S21) and 114 (S22) are closed, and switch 118 (Sw2) is open.

[0067] Figure 4 An embodiment of a heating system 60 is depicted, which includes components for promoting battery heating during charging. In this embodiment, heating is performed during a DC fast charging (DCFC) or Level 3 charging process. The output range of the DCFC charger can be from 50kW to 350kW, and it can recharge the EV battery assembly to 80% in a typical time period ranging from about 15 minutes to about 45 minutes.

[0068] In this embodiment, a leg of the first inverter 36 is connected to an energy source, such as a DCFC charging station, via a diode 122 (D3). The diode 122 (D3) prevents AC heating current from flowing into the charging station while allowing AC heating current to flow through the battery pack 24. A first charging switch 124 (Sc1) is connected to the positive terminal (DCFC+) of the charging station, and a second charging switch 126 (Sc2) is connected to the negative terminal (DCFC-) of the charging station. To put the first inverter 36 into heating mode and apply heating current, switch 94 (S11) is open, and switches 102 (Sw1) and 98 (S21) are closed.

[0069] When the inverter is in heating mode, the inverter legs are used to generate AC heating current by operating the legs as a quasi-resonant circuit (QRC). In the first inverter 36, switch 102 (Sw1), inductor 104 (L1), and capacitor 78 (C1) form the QRC for generating the heating current. In the second inverter 38, switch 118 (Sw2), inductor 120 (L2), and capacitor 92 (C2) form the QRC for generating the heating current.

[0070] For example, controller 62 operates switches 66 and 68 to generate a current with an AC waveform of selected amplitude and frequency. The AC heating current is superimposed on an existing current, which may be the current through another inverter 38 (if heating occurs during drive) or the charging current (if heating occurs during charging).

[0071] Figure 5 The diagram schematically illustrates the operation of the inverter 36 as a QRC (Quick Resistor) to generate an AC heating current when the inverter 36 is idle (e.g., during vehicle movement). The inverter 36 is controlled by a controller 62 to apply an AC heating current (represented by resistance R) through the battery pack 24. batt Inductor 104 is connected between node 130 (HB1) of the half-bridge (switches 66 and 68) and the positive terminal of battery pack 24. The resistance between inductor 104 and node 130 is represented by resistors R4 and R5.

[0072] Inverter 36 is also connected to various sensors for monitoring its parameters. For example, voltmeter 132 is provided to measure battery voltage V. batt It also provides an ammeter 134 to measure the battery discharge current (I0). batt Other sensors may include those for measuring the current (I) through inductor 104. L1 The system includes an ammeter 136 for measuring the current across a capacitor 78 and an ammeter 138 for measuring the current across the capacitor 78. The resistance between the ammeter 138 and the capacitor 78 is denoted as resistor R3. One or more sensors are configured to send the measurement results to a controller 62 to operate the QRC to provide heating.

[0073] Inverter 36 is operated to heat battery pack 24 by placing switch 68 in the ON or OFF state and switch 66 in the OFF or ON state for a period of time, allowing battery pack 24 to supply current through inductor 104. Subsequently, switch 68 is opened (entering the OFF state) and switch 66 is closed (entering the ON state) to connect inductor 104 and capacitor 78 and place a series LC combination across battery pack 24. Switch 68 remains in the OFF state, and switch 66 remains in the ON state for a sufficient period of time to allow QRC oscillation.

[0074] The controller 62 provides a control signal, such as a pulse width modulation (PWM) signal, which has a selected or preset period between pulses and pulse widths. The control signal is adjusted based on the desired heating amount by regulating signal parameters such as pulse width, duty cycle, frequency, and signal amplitude.

[0075] Controller 62 receives reference current (I) ref ), and continuously or periodically measure the sensed current value (I) from ammeter 136. sense The reference current can be a peak current indicator specifying the maximum peak current (Ipk) that can be applied. Controller 62 can control the PWM signal and control switching, and suspend the operation of the reference current beyond the peak current (e.g., via a NOT signal).

[0076] In this way, an AC heating current is applied to the battery pack 24. The AC heating current is superimposed on the current drawn by the inverter 38 (denoted as current I2).

[0077] Figure 6 An example of AC heating current applied using inverter 36 during vehicle motion is shown. Curve 140 shows the battery voltage V as a function of time. batt In this example, inverter 38 draws an average current I of 200A with a current ripple of 10A. inv2 As shown in curve 142, the current I through inductor 104... L1 As shown by curve 144, the voltage VCAP1 across capacitor C1 is shown by curve 146, and the current I through capacitor C1 is... CAP1 As shown in curve 148, the AC heating current and current I... inv2 Reflected in the discharge current I batt As shown in curve 150.

[0078] Figure 7 The operation of the inverter 36 as a QRC to generate an AC heating current during charging (e.g., DCFC) is schematically illustrated. In this example, the AC heating current is superimposed on the current I supplied by the DCFC charging station 152. dcfc Above. Inverter 36 is controlled by controller 62 to apply AC current through battery pack 24 via control switches 66 and 68, as combined. Figure 5 The topic under discussion. In this example, the battery current I... batt It includes the superposition of current I dcfc The net battery current of the AC heating current.

[0079] Figure 8An example of AC heating current generated by inverter 36 during DCFC is shown. Curve 160 shows the battery voltage V as a function of time. batt In this example, charging station 152 provides an average current I of approximately 280A with a current ripple of 10A. dcfc As shown in curve 162, the current I through inductor 104... L1 As shown by curve 164, the voltage V across capacitor C1 Cap1 As shown by curve 166, and the current V through capacitor C1 Cap1 As shown in curve 168, the AC heating current and current I... dcfc Reflected in net battery current I batt (Curve 170)

[0080] In one embodiment, the heating system 60 is configured to heat the battery pack 24 using a DC-DC converter in the vehicle 10. The DC-DC converter can be operated to generate a heating current using energy from an idle motor and / or energy from a charging station or other energy source during a charging (e.g., DCFC) process. In the hereinafter, the DC-DC converter used is DC-DC converter 32, but is not limited thereto.

[0081] Figure 9 An embodiment of a heating system 60 including a DC-DC converter 32 is depicted. In this embodiment, the DC-DC converter 32 is connected to a charging port 44 via a switching assembly 180. The switching assembly 180 includes switches 182 (S1), 184 (S2), and 186 (S3). The DC-DC converter 32 can be selectively connected to the charging port 44 by closing switches 182 (S1) and 184 (S2).

[0082] The DC-DC converter 32 includes a DC-DC converter bus 188 that connects the DC-DC converter 32 to the battery pack 24. A precharge switch 190 (SPC) is connected to a resistor and allows selective engagement of the battery pack 24 with the charging port 44. The system 60 also includes switches 206 (S7) and 208 (S8) for selectively connecting the DC-DC converter 32 to the inverter module 34.

[0083] The DC-DC converter 32 includes a capacitor 192 (C1) connected in parallel to a full-bridge switching configuration. In the full-bridge configuration, an inductor 194 is connected to a half-bridge including switches 196 (T1) and 198 (T3), and also to a half-bridge including switches 200 and 202 (C2). Switch 204 (S0) provides a bypass for the connection between the DC-DC converter 32 and the inverter module 34. If switch 204 (S0) is closed, the operation of the DC-DC converter in the inverter module 34 is bypassed.

[0084] Various switches are controllable to place the DC-DC converter 32 into heating mode. During vehicle operation, if heating is not required, switches 182 (S1), 184 (S2), and 186 (S3) are open, and switches 206 (S7) and 208 (S8) are closed. To place the DC-DC converter 32 into heating mode, switches 204 (S0), 206 (S7), and 208 (S8) are opened. Switches 182 (S1), 184 (S2), and 186 (S3) are closed to allow the battery pack 24 to supply power to the inverter module 34, while the DC-DC converter 32 generates AC heating current.

[0085] To generate AC heating current, switches 196 and 202 are controlled during the first half of the AC cycle to store energy across inductor 194 and capacitor 192, and then switches 198 and 200 are controlled during the second half of the AC cycle to discharge the stored energy back into battery pack 24. The flow path of the AC heating current is shown by arrow 214.

[0086] As described above, system 60 can be configured for heating during vehicle operation and / or charging. For heating during charging, diode 210 may be included to prevent AC heating current from flowing to the charging station or other energy source.

[0087] Figure 10 The operation of the heating system 60 applying AC heating current is illustrated. The controller 62 receives input data from the respective motor drivers (such as motor driver 213 connected to motor 20), including motor speed, torque, and motor currents Id and Iq for each motor 20 and 21. In this example, motor 20 is idle and therefore does not generate torque. The controller 62 also receives input data including the voltage V on the DC-DC bus 188 via an inverter in the TPIM (e.g., inverter 36). bus Phase current i abc Input data 211 includes the phase angle θ. Based on the input data, the controller 62 uses PWM modulation to apply AC heating current to the phase pins of the machine 20 to generate AC heating current in the DC-DC converter bus 188 and the battery pack 24.

[0088] Figure 11 An embodiment of method 300 for heating a battery assembly and / or other vehicle components or systems by controlling a conversion device in the vehicle is shown. Aspects of method 300 may be executed by controller 62 or other suitable processing device. Furthermore, method 300 is described in conjunction with vehicle 10 and its components, but is not limited thereto, as method 300 can be executed in conjunction with any suitable vehicle or battery assembly and any suitable type of conversion device.

[0089] Method 300 includes multiple steps or stages represented by boxes 301-312. Method 300 is not limited to the number or order of the steps, because some steps represented by boxes 301-312 may be performed in a different order than that described below, or fewer than all steps may be performed.

[0090] At box 301, the processing device determines whether the propulsion system of vehicle 10 is active (e.g., the vehicle is in motion and applying torque).

[0091] At box 302, if the propulsion system is not activated, the processing unit determines whether vehicle 10 is in charging mode (e.g., connected to a charging station and receiving charging current). For example, the processing unit determines whether vehicle 10 is in DCFC mode. If not, method 300 ends at box 303.

[0092] If vehicle 10 is in charging or DCFC mode, the internal temperature of battery pack 24 is measured or estimated at box 304. For example, the processing unit receives the temperature measurement from the RESS system. If the temperature is greater than or equal to a selected threshold, method 300 ends at box 303.

[0093] At box 305, if the temperature exceeds a threshold, the heating system 60 is controlled to apply an AC heating current. An inverter or DC-DC converter, as discussed herein, can be used to apply the AC heating current. The parameters of the current are controlled to achieve the desired temperature rise or rate of change, and the current parameters can be maintained until the temperature reaches the desired value or charging stops.

[0094] At box 306, if the propulsion system is active, the processing unit determines whether the battery pack temperature is at or below a threshold and / or whether heating is required. For example, the processing unit may receive priorities from the RESS system.

[0095] At box 307, if battery heating is required (e.g., RESS priority is high), the processing unit determines whether all-wheel drive (AWD) can be disabled. If so, AWD is disabled at box 308, and AC heating is performed (box 305).

[0096] At box 309, if battery heating is not desired, the processing unit determines whether to request cabin heating. If so, at box 310, the desired heating power is estimated. The heating power is estimated based on the cabin heating power, the additional heat from the vehicle's heat pump compressor, and the waste heat from the power electronics (PE). The desired heating power can be based on the following equation:

[0097]

[0098] At box 311, determine whether the desired heating power is greater than zero. If not, the method ends (box 312).

[0099] If the desired power is greater than zero, determine at box 313 whether AWD can be disabled. If so, disable AWD and apply AC heating to heat battery pack 24 at the desired rate of change (box 314).

[0100] Figure 12 An embodiment of method 330 for heating and / or controlling the temperature of a battery assembly is shown. Aspects of method 330 can be executed by controller 62 or other suitable processing device. Method 330 can be used to generate and control AC heating current to provide a uniform or constant temperature rise.

[0101] Method 330 includes multiple steps or stages represented by boxes 331-341. Method 330 is not limited to the number or order of the steps, because some steps represented by boxes 331-341 may be performed in a different order than that described below, or fewer than all steps may be performed.

[0102] At box 331, the desired rate of temperature rise of the battery cell is input to a processing device, such as controller 62. The desired rate is expressed as... .

[0103] At box 332, the temperature T of each battery cell in the battery module (e.g., module 26) is measured. cell The state of charge (SOC) is input into a lookup table (LUT). The LUT output impedance value R cell .

[0104] At box 333, the desired rate of temperature rise and impedance R cell The root mean square (RMS) value is used to estimate the expected current through each cell. This value is expressed as I*cell,RMS and can be calculated based on the following equation:

[0105]

[0106] In this equation, m mod It's the quality of the battery module, C p,modT is the specific heat capacity of the module, and hA is the product of the heat transfer coefficient and the effective area of ​​the cooling surface. cool It is the coolant temperature. I is calculated iteratively. cell,RMS The square root of this is used as the desired battery AC current I*. cell,RMS .

[0107] At box 334, the maximum allowable peak current I is calculated based on Rcell received from the LUT. cell,AC,peak,allowed In one embodiment, the value is calculated based on the following equation:

[0108]

[0109] α < 1,

[0110] Where V cellmin,meas It is the lowest battery voltage measured in the module, and V cellmax,meas This is the highest battery voltage measured in the module. V cellmin,lim It is the minimum battery cell voltage, and V cellmax,lim This is the maximum cell voltage. α is the current limiting factor.

[0111] At box 335, place I cell,AC,peak,allowed Convert to RMS to generate a representation as I cell,AC,RMS,allowed The value of .

[0112] At box 336, compare I*cell, RMS, and I. cell,AC,RMS,allowed Determine the lowest of these values. This value is expressed as the desired current RMS, which is fed forward (as denoted by I*). cell,ff, RMS The value is used to update the desired rate of temperature increase at box 337 (e.g., if the value exceeds the maximum allowable current through the battery).

[0113] At box 338, the desired temperature rise (or a newer desired temperature rise) is provided to the feedback control along with the measured temperature rise. If the measured rise rate exceeds the desired rise rate, the feedback control limits the desired current RMS.

[0114] At box 339, the desired current RMS (I*) is limited or constrained based on other temperature limitations (such as temperature limitations of power electronics). cell,RMS At box 340, the desired battery pack current is estimated based on the battery pack configuration (e.g., the number of modules) and constrained based on the power capacity of the heating system 60 (box 341). An AC heating current is applied to the battery pack 24, where I* batt (t) is based on I* cell,RMSThe peak current applied to the battery pack. The AC heating current has a frequency that is a function of battery temperature and SOC.

[0115] Figure 13 Aspects of embodiments of a computer system 440 are illustrated, which can perform various aspects of the embodiments described herein. The computer system 440 includes at least one processing means 442, which generally includes one or more processors for performing aspects of the image acquisition and analysis methods described herein.

[0116] The components of computer system 440 include processing device 442 (such as one or more processors or processing units), memory 444, and bus 446 connecting various system components, including system memory 444, to processing device 442. System memory 444 may be a non-transitory computer-readable medium and may include various computer system-readable media. Such media may be any available medium accessible by processing device 442, and includes volatile and non-volatile media as well as removable and non-removable media.

[0117] For example, system memory 444 includes non-volatile memory 448 such as a hard disk drive, and may also include volatile memory 450 such as random access memory (RAM) and / or cache memory. Computer system 440 may also include other removable / non-removable, volatile / non-volatile computer system storage media.

[0118] System memory 444 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments described herein. For example, system memory 444 stores various program modules that generally perform the functions and / or methods of the embodiments described herein. One or more modules 452 may be included to perform functions related to controlling heating operations as discussed herein. System 440 is not limited thereto, as other modules may be included. As used herein, the term "module" refers to processing circuitry, which may include application-specific integrated circuits (ASICs), electronic circuitry, processors (shared, dedicated, or grouped) and memories executing one or more software or firmware programs, combinational logic circuitry, and / or other suitable components that provide the described functions.

[0119] The processing device 442 can also communicate with one or more external devices 456, which may be a keyboard, an indicator, and / or any device that enables the processing device 442 to communicate with one or more other computing devices (e.g., a network interface card, a modem, etc.). Communication with various devices may occur via input / output (I / O) interfaces 464 and 465.

[0120] The processing unit 442 can also communicate with one or more networks 466 (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 468. It should be understood that, although not shown, other hardware and / or software components may be used in conjunction with the computer system 440. Examples include, but are not limited to, microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, and data archiving storage systems.

[0121] While the foregoing disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from its scope. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of this disclosure without departing from the basic scope of this disclosure. Therefore, it is intended that this disclosure be limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. A device for thermal control of a battery system, comprising: The heating control module is electrically connected to the battery system; and A conversion device configured to control the power output from the battery system, and a heating control module configured to perform: The current passing through the conversion device is measured, and the measured current is provided by an energy source during vehicle charging; The conversion device is controlled to generate an alternating heating current using the measured current; as well as The alternating current is applied to the battery system to heat the battery system to a desired temperature; The conversion device is a DC-DC converter, and controlling the conversion device includes: when the electric motor is idle, controlling the DC-DC converter to generate an AC heating current; and when the vehicle is charging, connecting the DC-DC converter to an idle inverter and controlling the DC-DC converter to use energy supplied by the energy source and the battery system to generate the AC heating current.

2. The apparatus of claim 1, wherein the vehicle includes a first electric motor connected to a first inverter and a second electric motor connected to a second inverter, and controlling the conversion device includes controlling a phase pin of the first inverter to generate the AC heating current.

3. The apparatus according to claim 2, wherein, The phase pin includes a quasi-resonant circuit with an inductor, a capacitor, and a half-bridge switch configuration, and controlling the phase pin includes controlling the quasi-resonant circuit to generate the AC heating current.

4. The apparatus according to claim 3, wherein, The first electric motor and the battery system provide a measured current when the first electric motor is idle.

5. The apparatus according to claim 2, wherein, Controlling the conversion device includes electrically connecting the energy source to a phase pin of the first inverter or a phase pin of the second inverter.

6. A method for thermally controlling a battery system in a vehicle, comprising: The current passing through a conversion device configured to control the power output from the battery system is measured, and the measured current is provided by an energy source during vehicle charging. The conversion device is controlled by the heating control module to generate an AC heating current using the measured current; as well as The alternating current is applied to the battery system to heat the battery system to a desired temperature; The conversion device is a DC-DC converter, and controlling the conversion device includes: controlling the DC-DC converter to generate the AC heating current when the electric motor is idle; and controlling the DC-DC converter to generate the AC heating current using energy supplied by the energy source and the battery system when the vehicle is charging.

7. The method according to claim 6, wherein, The vehicle includes a first electric motor connected to a first inverter and a second electric motor connected to a second inverter, and controlling the conversion device includes controlling the phase pins of the first inverter to generate the AC heating current.

Images