Battery control system

Abstract

The utility model relates to a battery control system which is used for controlling charging / discharging of a battery pack installed on an electric automobile. The battery control system (100) comprises a battery pack (102) consisting of power supply terminals (DC +, DC-) and relay contactors, a charge simulator unit (104) for simulating the state of charge of the battery pack (102), a load group (106) for discharging the battery pack (102), and a switch unit (108) for controlling the charge simulator unit (104) or the load group (106) to be connected with the power supply terminals (DC +, DC-). A switching unit (108) connects the charge emulator unit (104) to the power supply terminals (DC +, DC-) to control the relay contactor to switch to the closed state. A switching unit (108) connects the load group (106) to the power supply terminals (DC +, DC-) to cause the load group (106) to discharge the battery group (102).

Description

Technical Field

[0001] The utility model relates to a battery control device, in particular to a battery control system for controlling the charging and discharging of a battery pack installed in a hybrid vehicle or an electric vehicle. Background Art

[0002] Just because the background section mentions the subject matter discussed in the background section does not mean it is prior art. Similarly, it should not be assumed that problems mentioned in the background section or problems related to the subject matter in the background section are already recognized in the prior art. The subject matter in the background section merely represents different ways that, by themselves, may correspond to implementing the claimed technology.

[0003] Electric vehicles typically incorporate battery packs, such as lead-acid batteries, nickel-metal hydride batteries, lithium-ion batteries, solid-state batteries, and lithium-sulfur batteries. These battery packs provide the power needed for hybrid or electric vehicles. Battery packs installed in electric vehicles operate over a wide temperature range, with their maximum allowable power rating commensurate with the operating temperature. If the battery pack's charge or discharge exceeds the maximum allowable power rating, overcharging or overdischarging may occur.

[0004] To safely use a battery pack, its charge and discharge must be controlled within its maximum allowable power range. Electric vehicle charge and discharge control is essentially tested by discharging the battery pack installed on the vehicle after each charging cycle. This performance testing of the battery pack is typically performed by driving the vehicle on the road or using a chassis dynamometer, which uses one or more fixed roller assemblies to simulate different road conditions in a controlled environment. However, this battery pack performance testing technique is time-consuming and expensive per discharge cycle. Furthermore, conventional techniques are unable to perform accelerated durability testing on battery packs, which requires the battery pack to undergo multiple charge and discharge cycles to verify its performance under actual driving conditions. Furthermore, conventional techniques require driving the vehicle over long distances for durability testing, which is both time-consuming and costly.

[0005] Therefore, there is a need in the art to provide cost-effective technologies that can address the above-mentioned shortcomings while allowing performance testing of battery packs installed on electric vehicles and accelerated durability testing of battery packs in a time-saving and labor-saving manner without removing the battery pack from the vehicle. Utility Model Content

[0006] The purpose of the utility model is to provide a battery control system for performing performance testing on a high-voltage battery pack installed on an electric vehicle.

[0007] Another object of the present invention is to provide a battery control system capable of performing an accelerated durability test on a battery pack without removing the battery pack from a vehicle.

[0008] Another object of the present invention is to provide a cost-effective battery control system for performance testing of a battery pack.

[0009] Another object of the present invention is to provide a battery control system that can perform performance testing on a high-voltage battery pack within a shorter time interval than a traditional battery testing system.

[0010] This summary is intended to introduce various aspects related to battery control systems, which will be further described in the detailed description below. This summary is not intended to identify essential features of the claimed subject matter, nor is it intended to determine or limit the scope of the claimed subject matter.

[0011] One aspect of the present invention relates to a battery control system, comprising one or more relay contactors configured to control the supply of current to power terminals of a high-voltage (HV) battery pack. The battery control system further comprises: a charge emulator unit configured to simulate a state of charge of the battery pack; a load bank including at least one electronic load configured to discharge the battery pack; and a switch unit operatively connected to the charge emulator unit and the load bank and configured to selectively control the connection of the charge emulator unit and the load bank to the power terminals of the battery pack.

[0012] The switch unit is configured to connect the charge emulator unit to the power supply terminal so that current can be supplied from the charge emulator unit to the power supply terminal to control the switching of the one or more relay contactors from an open state to a closed state. The switch unit is also configured to disconnect the charge emulator unit and connect the load bank to the power supply terminal so that at least one electronic load can discharge the high-voltage battery bank while the one or more relay contactors are in a closed state and a charge state of the high-voltage battery bank is simulated.

[0013] According to one embodiment of the present invention, the switch unit includes a first switch connected between the charge simulator device and the power terminal, and a second switch connected between the load group and the power terminal.

[0014] According to one embodiment of the present invention, the battery pack provides power to a power control unit of the electric vehicle. The power control unit may be configured to regulate and control the power provided from the battery pack to the motor of the electric vehicle.

[0015] According to one embodiment of the present invention, the switch unit includes a communication unit connected between the charging simulator unit and the electric vehicle power control unit, wherein the communication unit is configured to maintain a closed state of one or more relay contactors after the charging simulator unit is disconnected from the power terminal.

[0016] According to one embodiment of the present invention, the at least one electronic load comprises an electronic load or a resistive load bank configured to discharge the high-voltage battery pack. Additionally or alternatively, the at least one electronic load comprises a programmable electronic load configured to discharge the high-voltage battery pack by providing a discharge current of the high-voltage battery pack to a power storage device.

[0017] According to one embodiment of the present invention, a power storage device includes a power grid and a secondary battery pack.

[0018] According to one embodiment of the present invention, the at least one electronic load includes a transient electronic load configured to charge and discharge the battery pack according to a predetermined driving cycle of the electric vehicle.

[0019] According to one embodiment of the present invention, a battery control system includes a sensing unit configured to detect the operating voltage and operating current of a battery pack, and a control unit connected to the sensing unit. The control unit is configured to generate an error signal based on the difference between the operating current of the battery pack or power storage device and the required current. The battery control system includes a first power converter configured to convert the discharge current of the high-voltage battery pack based on a power signal generated by the control unit and supply the converted discharge current to the power storage device.

[0020] According to one embodiment of the present invention, the load group further includes a second power converter configured to convert the discharge current of the high-voltage battery group according to the error signal generated by the control unit, and supply the converted discharge current to the grid according to a predetermined driving cycle of the electric vehicle.

[0021] Another aspect of the present invention relates to a battery control method, comprising controlling the connection of a charging emulator unit and a load pack to a power terminal of a battery pack via a switch unit. The battery control method further comprises connecting the charging emulator unit to the power terminal via the switch unit, switching a relay contactor of the battery pack from an open state to a closed state, and maintaining the closed state of the relay contactor via the switch unit after the charging emulator unit is disconnected from the power terminal. The switch unit is configured to connect the load pack to the power terminal so that at least one electronic load of the load pack discharges the battery pack while the relay contactor is in a closed state, thereby simulating a charging state of the battery pack.

[0022] According to one embodiment of the present invention, the battery control method further includes detecting the operating voltage and operating current of the battery pack by a sensing unit, and generating an error signal by a control unit based on the difference between the operating current of the battery pack or power storage device and the required current. A first power converter converts the discharge current of the battery pack based on the error signal generated by the control unit and provides the converted discharge current to the power storage device. A second power converter converts the discharge current of the battery pack based on the error signal generated by the control unit and provides the converted discharge current to the power terminal according to a predetermined driving cycle of the electric vehicle.

[0023] The principle of the present invention is described below with reference to the accompanying drawings. Other aspects and advantages of the present invention will become apparent from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings constitute part of the specification and are used to provide a further understanding of the present invention. These drawings illustrate embodiments of the present invention for the purpose of illustrating the principles of the present invention. The embodiments of the present invention are illustrated in the accompanying drawings by way of example and not limitation, and references in the accompanying drawings indicate similar elements. It should be noted that references to "one" or "an" embodiment in the present invention do not necessarily refer to the same embodiment, but rather to at least one embodiment. In the accompanying drawings:

[0025] Figure 1 is a schematic diagram of a battery control system according to an embodiment of the present utility model;

[0026] Figure 2A and 2B is a schematic diagram of a battery control system. According to one embodiment of the present invention, the system includes a switch unit for controlling the connection between the battery pack and the charging simulator device and the load group respectively;

[0027] Figure 3 A schematic diagram of a battery control system with a load group according to an embodiment of the present invention is shown;

[0028] Figure 4A and 4B Various schematic diagrams of a battery control system are shown. According to one embodiment of the present invention, the system is used to discharge a battery pack, and the load group includes an electronic load;

[0029] Figure 4C and 4D Various schematic diagrams of a battery control system are shown. According to one embodiment of the present invention, the system is used to discharge a battery pack of one vehicle and use the discharged energy of the battery pack to charge a secondary battery pack of another vehicle;

[0030] Figure 4E and 4FVarious schematic diagrams of a battery control system are shown. According to one embodiment of the present invention, the system is used to discharge a battery pack through a load bank and supply the discharged energy of the battery pack to a power storage device / grid;

[0031] Figure 5 is a schematic diagram of a battery control system. According to one embodiment of the present invention, the load group includes a transient load;

[0032] Figure 6A is a schematic diagram of a battery control system, according to one embodiment of the present invention, the system is used to discharge a battery pack through a transient load and provide discharge energy to the battery pack in the form of a charging current;

[0033] Figure 6B is a schematic diagram of a battery control system, according to one embodiment of the present invention, the system charges a battery pack via a transient load power supply;

[0034] Figure 7 A graph showing the state of charge (SOC) of a battery pack versus time (seconds) when a battery control system discharges the battery pack at a discharge current of 5A according to an embodiment of the present invention is shown;

[0035] Figure 8 This is a graph showing how the SOC of a battery pack changes over time (seconds) when the battery control system discharges the battery pack at a discharge current of 40 A according to an embodiment of the present invention;

[0036] Figure 9 is a flow chart describing the process involved in a battery control method according to an embodiment of the present utility model;

[0037] Figure 10 is a flow chart describing a process of discharging a battery pack together with any one of an electronic load, a power grid, or a secondary battery pack according to an embodiment of the present invention; and

[0038] Figure 11 This is a flow chart describing a process of discharging a battery pack under a transient load according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The detailed description provided below, in conjunction with the accompanying drawings, is a description of various embodiments of the present invention and does not represent the only embodiment in which the present invention may be practiced. Each embodiment described in this disclosure is intended merely as an example or illustration of the present invention and is not necessarily to be construed as superior or preferred over any other embodiment. The detailed description includes specific details for the purpose of providing a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

[0040] In the description herein and in the claims that follow, the meanings of "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Further, in the description herein, the meaning of "in" includes "on" and "on" unless the context clearly dictates otherwise.

[0041] The present utility model relates to a battery control system for controlling the charging and discharging of a battery pack installed in a hybrid vehicle or electric vehicle. The battery control system provides a cost-effective technology for performing performance testing and accelerated durability testing on a battery pack without the need for frequent assembly or disassembly of the battery pack from the vehicle. Compared to traditional battery testing techniques, the battery control system is able to perform performance tests on the battery pack in shorter time intervals. In addition, the battery control system allows the discharge energy of the battery pack to provide power to the power grid or secondary power storage devices. The battery control system of the present utility model also reduces risks during battery pack operation and improves safety.

[0042] Figure 1 A schematic diagram of a battery control system (hereinafter also referred to as the "system") 100 is shown, which includes a high-voltage (HV) battery pack 102 having one or more batteries and installed in an electric vehicle (hereinafter also referred to as the "electric vehicle"). The battery pack 102 can be configured to provide power to a power control unit of the electric vehicle. The power control unit can be configured to regulate the power supplied from the battery pack 102 to the motor of the electric vehicle. The battery pack 102 includes power terminals DC+ and DC-, and one or more relay contactors for controlling the power supply to the positive and negative power terminals DC+ and DC- of the battery pack 102. The battery pack 102 also includes a control pilot terminal CP and a proximity pilot terminal PP line for establishing power line communication (PLC) (interpreted in the SAE J1772, DIN Spec 70121 standards) between the electric vehicle and the battery control system 100. Initially, the relay contactor is in an open state. After PLC communication is established, the relay contactor, which is part of the electric vehicle, is in a closed state.

[0043] The battery control system 100 includes a charge simulator unit 104 configured to simulate the state of charge of a battery pack 102, and a load bank 106 including at least one electronic load configured to discharge the high-voltage battery pack 102. The charge simulator unit 104 can be a star charger or a direct current (DC) charger. A battery monitoring system (BMS) / vehicle control unit (VCU) has a proximity pilot terminal PP configured to detect the connection between the charge simulator unit 104 and the electric vehicle's power control unit. The power control unit can be configured to regulate the power supplied from the battery pack 102 to the electric vehicle's motor. The proximity pilot terminal PP communicates with the electric vehicle's power control unit and notifies the power control unit's battery management unit (BMU) / vehicle control unit (VCU) that the charge simulator unit 104 is electrically connected to the power supply terminals DC+ and DC- of the battery pack 102. Terminals PP and CP of the BMS / VCU establish PLC communication between the DC+ and DC- terminals of the electric vehicle's high-voltage battery pack 102 and the charge simulator 104. The charge simulator unit 104 can be connected to the power supply terminals DC+ and DC- at the air intake.

[0044] The electronic load of load group 106 can be appropriately selected from the group consisting of a resistive / electronic load, a programmable load, and a transient load, depending on the discharge current supply requirements of battery pack 102. When using a resistive load, load group 106 can dissipate the discharge current of battery pack 102 into the surrounding environment in the form of waste heat. A programmable load enables load group 106 to supply the discharge current of battery pack 102 to a power grid or power storage device, such as a secondary battery pack or a capacitor bank for storage. A transient load enables load group 106 to resupply the discharge current to the DC+ and DC- power terminals of battery pack 102, thereby continuously charging and discharging battery pack 102 according to a predetermined driving cycle of the electric vehicle, thereby performing accelerated durability testing on battery pack 102.

[0045] System 100 also includes a switch unit 108 operatively connected to charge emulator unit 104 and load bank 106. Switch unit 108 is configured to selectively control the electrical connection between charge emulator unit 104 and load bank 106 and power supply terminals DC+ and DC- of battery bank 102. Switch unit 108 may include a first switch 108-1 connected between charge emulator unit 104 and power supply terminals DC+ and DC-, and a second switch 108-2 connected between load bank 106 and power supply terminals DC+ and DC-. First switch 108-1 and second switch 108-2 are solid-state semiconductor switches, such as miniature circuit breaker (MCB) switches.

[0046] The CP and PP terminals connected to the vehicle BMS / VCU are configured to provide power line communication (PLC) between the charging simulator unit 104 and the high voltage battery pack 102 of the electric vehicle. Figure 2A The figure shows a schematic diagram of a battery control system 100, in which a switch unit 108 controls the connection between the high-voltage battery pack 102 and the charging simulator unit 104. The first switch 108-1 of the switch unit 108 switches from an open state (OFF) to a closed state (ON), allowing power from the charging simulator unit 104 to the power supply terminals DC+ and DC- of the high-voltage battery pack 102, thereby switching the control pilot terminal CP to a closed state. This supply of current switches the high-voltage battery pack 102 to a charging state. In this state, both the CP and PP terminals notify the electric vehicle power control unit (BMU) that the charging simulator unit 104 is electrically connected to the power supply terminals DC+ and DC-. The switch unit 108 includes a communication device 110 that connects the charging simulator unit 104 and the electric vehicle power control unit. Communication unit 110 utilizes power line communication (PLC) compliant with the SAE J1772 / AIS138 standard to connect the charging simulator 104 and the vehicle's high-voltage battery pack 102. After the charging simulator unit 104 and the high-voltage battery pack 102 complete the handshake process, the communication unit 110 maintains the high-voltage relay contactor in a closed state even if the charging simulator unit 104 is disconnected from the power supply terminals DC+ and DC-. The communication unit 110 is implemented by providing a terminal in the charging simulator unit 104 to indicate to the BMU that the battery pack 102 is still charging even if the charging simulator unit 104 is disconnected from the power supply terminals DC+ and DC- of the high-voltage battery pack 102.

[0047] Figure 2B Another schematic diagram of the battery control system 100 is shown, in which the switch unit 108 controls the connection between the high-voltage battery pack 102 and the load bank 106 after the charging simulator unit 104 is disconnected. Once the high-voltage battery pack 102 on the electric vehicle is in a charging state, the first switch 108-1 is switched to an open state (off state). Thereafter, after the charging current supplied to the power supply terminals DC+ and DC- of the high-voltage battery pack 102 reaches approximately zero (amperes), the second switch 108-2 is switched to a closed state (on state). The second switch 108-2 of the switch unit 108 connects the load bank 106 to the power supply terminals DC+ and DC-, enabling the electronic load to discharge the high-voltage battery pack 102. Simultaneously, the communication unit 110 controls the pilot terminal CP to remain in a closed state, initiating the discharge state of the high-voltage battery pack.

[0048] Figure 3A schematic diagram of a battery control system 100 is shown. The load group 106 includes an electronic load 302 configured to discharge the high-voltage battery pack 102 and a programmable load. The programmable load discharges the battery pack 102 by providing the discharge current from the battery pack 102 to one or more power storage devices, such as a power grid 304-1 and a secondary battery pack 304-2. The electronic load 302 may include one or more electronic components, such as transistors, diodes, inductors, resistors, and capacitors, which discharge the battery pack 102 by transferring the discharge current from the battery pack 102 to the surrounding environment as waste heat. The electronic load 302 may be a resistive load comprising multiple resistors connected in parallel, adapted to transfer the discharge current from the battery pack 102 to the surrounding environment as waste heat. A heat dissipation device, such as a fan or blower, may be used to dissipate the heat to the surrounding environment. The secondary battery pack 304-2 may power another electric vehicle. Therefore, the programmable load may be used for vehicle-to-vehicle (V2V) charging of the secondary battery pack 304-2.

[0049] The battery control system 100 includes a sensing unit 306 having multiple sensors for detecting operating parameters of the battery pack 102 powering the electric vehicle, such as operating voltage, operating current, and operating temperature. The system 100 also includes a control unit 308 connected to the sensing unit 302. The control unit 308 can be configured to generate an error signal (hereinafter referred to as the "error signal") based on the difference between the operating current detected by the sensing unit 306 and the current demanded by the battery pack 102. The current demand can be user-defined.

[0050] The battery control system 100 also includes a first power converter 310 configured to convert the discharge current of the battery pack 102 into an appropriate form based on an error signal generated by the control unit 308 and provide the converted discharge current to the power grid 304-1 or the secondary battery pack 304-2. The first power converter 310 can be selected from the group consisting of an inverter, an alternating current (AC)-direct current (DC) converter, a DC-AC converter, and a DC-DC converter. Furthermore, the system 100 can also include a plurality of electronic switches 312, including solid-state semiconductor switches, gates, insulated gate bipolar transistors (IGBTs), metal oxide silicon field effect transistors (MOSFETs), etc., for regulating the discharge current and voltage of the battery pack 102 to the electronic load 302 and the power storage device. The system 100 can also include one or more power line controller (PLC) communication units 314-1 for establishing communication between the control unit 308 and the electric vehicle powered by the high-voltage battery pack 102 and another electric vehicle powered by the secondary battery pack 304-2. PLC unit 314-1 is connected to the electric vehicle's control pilot terminal (CP) to establish communication between the control unit 308 and the electric vehicle when the charging emulator unit 104 is connected to the DC+ and DC- power terminals of the battery pack 102 powering the electric vehicle. In a V2V discharge topology, PLC units 314-1 and 314-2 establish communication between the two electric vehicles via the PP and CP terminals of the respective battery packs 102 and 304-2. PLC units 314-1 and 314-2 are used to establish a handshake between the control unit 308 and the electric vehicle. Once the handshake is completed, the relay contactors of the electric vehicle powered by battery pack 102 are switched to a closed state. Once communication between the control unit 308 and the electric vehicle is established, PLC unit 314-1 notifies the control unit 308 to execute the charging and discharging processes of the battery pack 102. PLC units 314-1 and 314-2 can enable communication in accordance with ISO 15118, IEC 61851, SAE J1772, and DIN SPEC 70121 standards. The system 100 may further include a low voltage (LV) power supply 316 configured to power the PLC units 314 - 1 and 314 - 2 and the control unit 308 .

[0051] Figure 4A and 4BThe battery control system 100 is shown discharging the battery pack 102 installed in an electric vehicle through the electronic load 302 of the load bank 106. When the charge simulator unit 104 is connected to the power supply terminals DC+ and DC- via the inlet of the electric vehicle's power control unit, the PLC unit 314 communicates with the electric vehicle's relay contactors to establish communication between the control unit 308 and the electric vehicle's power control unit. The sensing unit 306 detects the operating current and voltage of the high-voltage battery pack 102 and feeds this information back to the control unit 308. The control unit 308 provides closed-loop control of the voltage and current. The sensing unit 306 includes a current sensing resistor or any other current sensing device configured to sense the load current and provide feedback to an amplifier. The amplifier provides closed-loop control and transmits an error signal to one or more gates of an electronic switch 312. The error signal is defined as the difference between the sensed current and the demanded / desired current. The generated error signal is the difference between the parameter detected by the sensing unit 306 and a user-defined parameter. The control unit 308 generates a pulse-width modulated (PWM) signal based on the error signal and inputs it to the gate of the electronic switch 312. The PWM signal received from the control unit 308 drives the electronic switch 312. The resistance of the electronic load 302 is changed by switching the corresponding electronic switch 312 on or off, depending on the current required to be drawn from / discharged by the battery pack 102. For example, if a larger discharge current is required from the battery pack 102, a lower resistance is automatically selected for the electronic load 302 by appropriately switching the electronic switch 312. After selecting the appropriate resistance, the discharge current provided by the battery pack 102 is converted into waste heat and discharged into the surrounding environment. During this operation, the control unit 308 and the electronic switch 312 prevent the discharge current from flowing to the first power converter (inverter) 310 and the secondary battery pack 304-2. Therefore, when the discharge current is provided to the electronic load 302, the first power converter (inverter) 310, the power grid 304-1, and the secondary battery pack 304-2 are all in an inoperative state. The first power converter 310 may further include multiple electronic switches, such as solid-state semiconductor switches. The first power converter 310 and the electronic switch 310 are driven and controlled by the switching unit 108.

[0052] Now please look Figure 4C and Figure 4DThe figure shows battery control system 100 discharging battery pack 102 installed on an electric vehicle through secondary battery pack 304-2 installed on another electric vehicle. When charging simulator unit 104 is connected to power supply terminals DC+ and DC- via the incoming port of the electric vehicle's power control unit, PLC unit 314 communicates with the relay contactors of both electric vehicles, establishing communication between control unit 308 and the electric vehicle's power control unit. Sensing unit 306 detects the operating current and voltage of battery pack 102 and secondary battery pack 304-2 and transmits this information to control unit 308. Other charging vehicles will require charging current, and control unit 308 generates an error signal based on the current demand, which is the difference between the detected current of secondary battery pack 304-2 and the required current. Control unit 308 also generates a PWM signal based on the error signal and transmits it to the gate of electronic switch 312.

[0053] Based on the error signal, the duty cycle of the PWM signal is provided to the electronic switch 312, which switches on and off to maintain a constant voltage and current throughout the discharge cycle of the battery pack 102. The electronic switch 312 utilizes a buck / boost converter topology to provide the appropriate voltage based on the operating voltage of the secondary battery pack 304-2 installed in the other vehicle. The roles of the battery pack 102 and the secondary battery pack 304-2 can be automatically reversed based on their state of charge (SOC). For example, the battery pack 102 / 304-2 of one vehicle with a higher SOC can charge the battery pack 102 / 304-2 of another vehicle with a lower SOC. This is achieved using the control unit 308 and the electronic switch 312, which acts as a mediator between the two vehicles. The mediator provides controlled current and voltage functions based on the requirements of the vehicle being charged, thereby avoiding drawing excess current from the battery pack being discharged. During this phase, control unit 308 and electronic switch 312 prevent the discharge current from flowing to first power converter (inverter) 310 and electronic load 302. Therefore, when the discharge current from battery pack 102 flows to secondary battery pack 304-2, first power converter (inverter) 310, grid 304-1, and electronic load 302 are all in an inoperative state. Control unit 308 may include a controller, a memory, and a user input interface.

[0054] Figure 4E and 4FThe battery control system 100 is shown discharging the battery pack 102 installed in an electric vehicle via the power grid 304-1. When the charging simulator unit 104 is connected to the power supply terminals DC+ and DC- via the incoming port of the electric vehicle's power control unit, the PLC unit 314 communicates with the electric vehicle's relay contactors to establish communication between the control unit 308 and the electric vehicle's power control unit. The sensing unit 306 detects the operating current and voltage of the battery pack 102 and transmits this information to the control unit 308. The control unit 308 provides closed-loop voltage and current control. The current sense resistor in the sensing unit 306 detects the load current and provides feedback to the amplifier. The amplifier provides closed-loop control and transmits an error signal to one or more gates of the first power converter 310. The error signal is defined as the difference between the sensed current and the demanded / desired current. The error signal is generated by the control unit 308 and is the difference between the parameter detected by the sensing unit 306 and a predetermined parameter. The control unit 308 generates a PWM signal based on the error signal and transmits it to the first power converter (inverter) 310. Control unit 308 is also configured to maintain the power factor of the current provided to inverter 310 at a near-unity level. Control unit 308 also provides a user-defined desired AC grid frequency and voltage. Inverter 310 converts the DC power of the discharge current into AC power and provides the converted discharge current to grid 304-1.

[0055] The benefit of using vehicle-to-grid (V2G) discharge is that during a power outage, the electric vehicle's onboard battery pack 102 can be used to power household AC appliances or small industrial equipment. The PWM signal generated by the control unit 308 drives the electronic switch of the inverter 310. The electronic switch of the inverter 310 opens or closes according to the electric vehicle's duty cycle to maintain a constant voltage and current during the discharge cycle of the battery pack 102. During this operation, the control unit 308 blocks the discharge current from the electronic switch 312 and the electronic load 302. Therefore, when the discharge current from the battery pack 102 is supplied to the grid 304-1, the electronic load 302 and the secondary battery pack 304-2 are inactive.

[0056] Figure 5A schematic diagram of the battery control system 100 is shown. The load group 106 includes a resistive load 502 and a transient load 504. The resistive load 502 is used to discharge the high-voltage battery pack 102, and the transient load 504 is used to charge the high-voltage battery pack 102. The resistive load 502 may include one or more resistors connected in parallel, series, or a combination of both. It discharges the high-voltage battery pack 102 by transferring the discharge current from the high-voltage battery pack 102 into its surroundings as waste heat. A heat sink (such as a fan) may be used to dissipate heat into the surroundings. The transient load 504 is a power module configured to supply current to the DC+ and DC- power terminals of the high-voltage battery pack 102. The transient load 504 can simulate the charging and discharging conditions of an electric vehicle on the road in a controlled environment, such as a laboratory. When the vehicle is accelerating, the motor powered by the high-voltage battery pack 102 consumes the energy stored therein. When the vehicle is decelerating, the motor acts like a generator and performs regenerative braking to supply power to the high-voltage battery pack 102.

[0057] To simulate charging and discharging conditions from the road to the lab, the transient load 504 supplies current to the power terminals DC+ and DC- of the battery pack 102 according to the driving cycle of the electric vehicle. The driving cycle is defined by the user and may include vehicle parameters such as operating current and voltage, charge / discharge parameters, throttle position, etc. The driving cycle data is predetermined by the user and takes into account peak data indicating worst-case scenarios, which helps to compress the time of the charging and discharging conditions. Based on the demand current (positive or negative) required by the battery pack 102, the system 100 charges and discharges the battery pack 102. The resistive load 502 and the transient load 504 are used to perform accelerated durability testing on the battery pack 102, which includes charging and discharging the battery pack 102 according to the vehicle's driving cycle.

[0058] System 100 includes a sensing unit 506 and a control unit 508. Sensing unit 506 is used to detect operating parameters of a battery pack 102 powering an electric vehicle, such as operating voltage and operating current. Control unit 508 is connected to sensing unit 506. Control unit 508 can be configured to generate an error signal (hereinafter referred to as the "error signal") based on the difference between the operating current detected by sensing unit 506 and the required current of battery pack 102. Control unit 508 can have a configuration similar to control unit 308. System 100 also includes a second power converter 510, which is configured to convert the discharge current of battery pack 102 into a suitable form based on the error signal generated by control unit 508 and re-supply the converted discharge current to power terminals DC+ and DC- of battery pack 102. Second power converter 510 can be selected from the group consisting of a DC-to-AC converter, an AC-to-DC converter, and a DC-to-DC converter. Second power converter 510 can also include a solid-state semiconductor switch. Second power converter 510 can also include a plurality of electronic switches. Furthermore, the system 100 may include a plurality of electronic switches 512, including solid-state semiconductor switches, gates, IGBTs, MOSFETs, and the like, to regulate the discharge current from the battery pack 102 to the resistive load 502 and the transient load 504. A sensing unit 506, including a current sensing resistor, senses the load current and provides feedback to an amplifier. The amplifier provides closed-loop control and transmits an error signal, defined as the difference between the sensed current and the demanded / desired current, to one or more gates of the electronic switches 512. The error signal is defined as the difference between the sensed current and the demanded / desired current. The system 100 may include a power line communication (PLC) unit 514. When the charging emulator unit 104 is connected to the DC+ and DC- power terminals of the battery pack 102, communication is established between the control unit 508 and the electric vehicle powered by the battery pack 102 via the PP and CP terminals. The system 100 may also include a low-voltage (LV) power supply 516 configured to power the PLC unit 514 and the control unit 508. The second power converter 510 and the electronic switches 512 are driven and controlled by the switching unit 108.

[0059] Figure 6A is a schematic diagram of a battery control system 100 for discharging a battery pack 102 through an electronic load 502 . Figure 6BFIG2 is another schematic diagram of the battery control system 100, which provides charging current to the battery pack 102 from the power control unit 504. When the charging simulator unit 104 is connected to the DC+ and DC- power terminals of the battery pack 102 via the electric vehicle power control unit's incoming line port, the PLC unit 514 establishes communication between the control unit 508 and the vehicle power control unit. The sensing unit 506 includes multiple sensors for detecting the operating voltage and current of the battery pack 102 during charging and discharging conditions. The operating voltage and current of the battery pack 102 detected / monitored by the sensing unit 506 are transmitted to the control unit 508. The control unit 508 provides closed-loop control of the voltage and current. The control unit 508 generates an error signal (error signal) that is the difference between the detected current value and the required / desired current for the vehicle's driving cycle. The control unit 508 uses the error signal to generate a PWM signal and inputs it to the gate of the electronic switch 512. The required current is positive when the battery pack 102 is discharging and negative when the battery pack 102 is charging. The required current is determined based on the vehicle's driving cycle.

[0060] The control unit 508 discharges the high-voltage battery pack 102 by providing a discharge current to the resistive load 502, and the resistive load 502 dissipates the discharge current into the surrounding environment in the form of waste heat. When the vehicle speed and the throttle position are greater than zero, the battery pack 102 begins to discharge. During the discharge process through the resistive load 502, the PWM signal generated by the control unit 508 drives the respective electronic switches 512 to allow a specific discharge current to flow to the resistive load 502. According to the required current extracted from the battery pack 102 in a predetermined vehicle driving cycle, the resistance of the resistive load 502 is changed / selected by turning on or off the corresponding electronic switch 512. For example, if a large discharge current needs to be extracted from the battery pack 102, the resistive load 502 with a lower resistance value is automatically selected by appropriately switching the electronic switch 312. After selecting the appropriate resistor, the discharge current supplied from the battery pack 102 will be converted into waste heat and discharged into the surrounding environment. During the discharge process, the control unit 508 and the second power converter 510 will prevent the discharge current from flowing to the transient load 504. Therefore, if Figure 6A As shown, during this phase, the power module / transient load 504 is not operational.

[0061] Once the vehicle's throttle position is zero and the vehicle speed is greater than zero (regenerative braking or deceleration), charging of the battery pack 102 is initiated through the power module of the transient load 502. During charging through the transient load 504, the PWM signal generated by the control unit 508 drives the various electronic switches of the second power converter 510, causing the discharge current to flow to the transient load 504. The transient load 504 then processes the discharge current and provides it to the battery pack 102 in the form of a charging current. The charging current is provided to the battery pack 102 through the transient load 504, depending on the user-defined electric vehicle driving cycle. The required power is provided to the battery pack 102 by turning on or off the corresponding electronic switch of the power converter 510. At this stage, the control unit 508 and the electronic switch 512 prevent the discharge current from flowing to the resistive load 502. Therefore, as Figure 6B As shown, during charging, the discharge of the battery pack 102 through the resistive load 502 is inactive. In addition, when the vehicle in which the battery pack 102 is installed is in an idle state, the control unit 508 blocks the discharge current from flowing to the resistive load 502 and the transient load 504. Therefore, in the idle state where the throttle position and vehicle speed are both zero, neither discharge nor charging is active.

[0062] Figure 7 A graph showing the SOC of the battery pack 102 versus time (in seconds) is shown. The battery pack 102 is discharged using an electronic load or a resistive load 302 / 502 at a discharge current of 5A. The discharge process begins at an SOC of 63.5%. It is observed that the SOC of the battery pack 102 drops to approximately 60% within 1 hour and 10 minutes. Figure 8 Another graph shows the SOC of battery pack 102 as a function of time (in seconds) while the battery pack 102 is discharged using electronic load 302 / 502 at a discharge current of 40A. The SOC at the beginning of the discharge process is 46%. It is observed that the SOC of battery pack 102 drops to approximately 40% within 16 minutes. The results show that by reducing the resistance value, the battery pack 102 is discharged faster. In addition, the results show that the battery pack 102 is successfully discharged through load pack 106 without having to drive the electric vehicle on the road or on a chassis dynamometer. This reduces the time and cost required for electric vehicle testing and configuration.

[0063] Figure 9Flowchart 900 is a flowchart describing various processes involved in a battery control method 900. The battery control method (hereinafter also referred to as the "method") 900 includes a step S902 of controlling the connection of a charge emulator unit 104 and a load bank 106 to power supply terminals DC+ and DC- of a battery bank 102 installed in an electric vehicle via a switch unit 108. The method 900 also includes a step S904 of connecting the charge emulator unit 104 to the power supply terminals DC+ and DC- via the switch unit 108 to switch one or more relay contactors of the battery bank 102 from an open state to a closed state, and a step S906 of maintaining the closed state of the relay contactors via the switch unit 108 after the charge emulator unit 104 is disconnected from the power supply terminals DC+ and DC-. Thereafter, in step S908, the switch unit 108 connects the load bank 106 to the power supply terminals DC+ and DC- to discharge the at least one electronic load of the load bank 106 into the battery bank 102 while the relay contactors are closed, thereby simulating the charging state of the battery bank 102.

[0064] The method 900 further includes detecting the operating voltage and operating current of the battery pack 102 by the sensing unit 306 / 506, and generating an error signal (error signal) by the control unit 308 / 508 based on the difference between the operating current and the required current of the battery pack 102 or the power storage device. The method 900 includes converting the discharge current of the battery pack 102 by the first power converter 310 based on the error signal generated by the control unit 308 / 508, and providing the converted discharge current to the power storage device. Additionally or alternatively, the method 900 further includes converting the discharge current of the battery pack 102 by the second power converter based on the error signal generated by the control unit 308 / 508, and providing the converted discharge current to the power supply terminals DC+ and DC- according to a predetermined driving cycle of the electric vehicle.

[0065] Now please look Figure 10The flowchart in the figure shows the discharge of the battery pack 102 with either the electronic / resistive load 302, the grid 304-1 (V2G), or the secondary battery pack 304-2 (V2V). When the charging emulator unit 104 is connected to the DC+ and DC- power supply terminals of the battery pack 102, the PLC units 314-1 and 314-2 establish communication between the control unit 308 and the electric vehicle via the PP and CP terminals of the electric vehicle's BMU / VCU and the secondary battery pack 304-2 in step S1002. Subsequently, in step S1004, the sensing unit 306 detects the current, voltage, and other parameters of the battery pack 102. The sensed battery pack 102 parameters are sent to the control unit 308. The control unit 308 then generates an error signal in step S1006 and adjusts the PWM duty cycle, which is then fed to the first power converter 310. Thereafter, in step S1008 , the battery pack 102 is discharged using any one of the electronic load 302 , the grid 304 - 1 , or the secondary battery pack 304 - 2 as needed.

[0066] Figure 11 This is a flow chart describing the discharge process of the battery pack 102 under the action of a transient load 504. When the charging simulator unit 104 is connected to the power terminals DC+ and DC- of the battery pack 102, the PLC unit 514 establishes communication between the control unit 508 and the electric vehicle powered by the battery pack 102 via their respective PP and CP terminals in step S1102. Subsequently, in step S1104, the sensing unit 506 detects the current, voltage, and other parameters of the battery pack 102. The sensed parameters of the battery pack 102 are transmitted to the control unit 508. The control unit 508 then generates an error signal in step S1106, adjusts the PWM duty cycle, and feeds it to the second power converter 510. Thereafter, in step S1108, the battery pack 102 is discharged using the electronic / resistive load 502 according to a predetermined driving cycle. Discharge is initiated whenever the electric vehicle's speed and throttle position are greater than zero. Alternatively, after step S1106, the power module of the transient load 504 charges the battery pack 102 according to the predetermined driving cycle. Once the electric vehicle's throttle position is zero and the speed is greater than zero (regenerative braking / deceleration), charging of the battery pack 102 is activated.

[0067] The battery control system and method of this utility model effectively control the charging and discharging of battery packs installed in hybrid or electric vehicles. The battery control system and method provide a cost-effective and time-efficient means for performance testing of battery packs installed in electric vehicles and accelerated durability testing of high-voltage battery packs, without the need to frequently remove the battery pack or other components from the vehicle. The battery control system is capable of performing performance testing of battery packs under extreme environmental conditions and accurately estimating the battery's service life based on performance testing and accelerated durability testing.

[0068] In view of the description of the present invention in this disclosure, all changes, modifications, and variations within the meaning and scope of equivalents are considered to be within the scope of the present invention. It should be understood that the various aspects and embodiments of the above disclosure may be used in any combination. Several aspects and embodiments may be combined to form further embodiments of the present invention.

Claims

1. A battery control system, comprising: a battery pack including a power terminal and one or more relay contactors configured to control a current supply to the power terminal; a charging emulator unit configured to emulate a charging state of the battery pack; a load bank comprising at least one electronic load configured to discharge the battery bank; as well as a switch unit operatively connected to the charge emulator unit and the load pack and configured to selectively control connection of the charge emulator unit and the load pack to power terminals of the battery pack, in, a switch unit connecting the charging emulator unit to the power supply terminal to enable current to be supplied from the charging emulator unit to the power supply terminal to control switching of the one or more relay contactors from an open state to a closed state; The switch unit disconnects the charge emulator unit and connects the load bank to the power terminals to enable the at least one electronic load to discharge the battery bank while the one or more relay contactors are in a closed state and a charge state of the battery bank is simulated.

2. The battery control system according to claim 1, wherein: The switch unit includes: a first switch connected between the charge simulator unit and the power supply terminal; and The second switch is connected between the load group and the power supply terminal.

3. The battery control system according to claim 1, wherein: The battery pack supplies electrical energy to the electric vehicle's power control unit.

4. The battery control system according to claim 3, wherein: The switch unit includes: A communication unit is connected between the charge emulator unit and the power control unit, the communication unit being configured to maintain a closed state of the one or more relay contactors after the charge emulator unit is disconnected from the power terminal.

5. The battery control system according to claim 1, wherein: The at least one electronic load includes an electronic load configured to discharge the battery pack.

6. The battery control system according to claim 1, wherein: The at least one electronic load includes a programmable electronic load configured to discharge the battery pack by supplying a discharge current of the battery pack to the power storage device.

7. The battery control system according to claim 6, wherein: Power storage devices include power grids and secondary battery packs.

8. The battery control system according to claim 6, wherein: Also includes: a sensing unit configured to detect an operating voltage and an operating current of the battery pack; a control unit connected to the sensing unit, the control unit being configured to generate an error signal according to a difference between an operating current of the battery pack or the power storage device and a demand current; The first power converter is configured to convert a discharge current of the battery pack according to the error signal generated by the control unit and supply the converted discharge current to the power storage device.

9. The battery control system according to claim 3, wherein: The at least one electronic load includes a transient electronic load configured to charge and discharge the battery pack according to a predetermined driving cycle of the electric vehicle.

10. The battery control system according to claim 9, wherein: Also includes: The second power converter is configured to convert a discharge current of the battery pack according to the error signal generated by the control unit and supply the converted discharge current to the grid according to a predetermined driving cycle, throttle position, and instantaneous speed of the electric vehicle.

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