Method for switching between fast charging modes

Abstract

A method of switching between fast charging modes is provided that is capable of changing a fast charging mode after determining an initial charging mode by taking into account a current voltage of a vehicle high-voltage battery and a charger output voltage. The method includes exchanging information between the charger and the vehicle, a charge controller of the vehicle comparing a high-voltage battery maximum voltage and a charger maximum output voltage according to the exchange of information, and when the high-voltage battery maximum voltage is greater than the charger maximum output voltage, starting the vehicle to charge the charger when the high-voltage battery maximum voltage is greater than the charger maximum output voltage. The charging controller compares the current voltage of the high-voltage battery with the maximum output voltage of the charger, and when the current voltage of the high-voltage battery is larger than the maximum output voltage of the charger, the charging controller enters a boost charging mode.

Description

Technical Field

[0001] This disclosure relates to charging technology, and more specifically, to a method for switching between fast charging modes in a multi-charge vehicle. Background Technology

[0002] In the case of vehicle boost charging systems, there are non-insulated boost charging systems that increase voltage by utilizing the vehicle motor / inverter, and insulated boost charging systems that utilize a separate converter.

[0003] Vehicles using this type of boost charging system typically have two fast charging modes, such as boost charging mode and direct charging mode. This is referred to as multi-charging.

[0004] In the vehicle, when the maximum voltage of the high-voltage battery is greater than the maximum voltage of the charger, the vehicle enters boost charging mode and increases the voltage to charge the high-voltage battery. Conversely, when the maximum voltage of the vehicle's high-voltage battery is less than the maximum voltage of the charger, the vehicle enters direct charging mode and charges the high-voltage battery.

[0005] Typically, in vehicles with high-voltage batteries of 500V or higher, at the start of charging, the fast charging mode (boost charging or direct charging) is determined by comparing the maximum voltage of the high-voltage battery with the maximum output voltage of the charger. Based on this determination, the charging mode will not be changed after charging begins until charging is complete.

[0006] Therefore, the advantage of entering boost charging mode is that charging can continue even when the charger's maximum output voltage is lower than the high-voltage battery's maximum voltage. However, the problem is that throughout the charging period, the boost converter consumes power to switch and increase the voltage, resulting in a decrease in overall charging efficiency and performance.

[0007] Furthermore, during periods when the current voltage of the high-voltage battery is lower than the charger's maximum output voltage, direct charging can be performed instead of boost charging. However, when fast charging is initiated, the charging mode is determined using only information about the charger's maximum output voltage and the high-voltage battery's maximum voltage. Therefore, boost charging mode will operate even within this range, and the problem is that the power consumed by switching to increase the voltage leads to reduced charging efficiency and / or performance.

[0008] Meanwhile, when fast charging enters direct charging mode, the advantage is that, compared to boost charging, the boost converter does not need to perform a switching operation to increase the voltage, thus improving charging efficiency and / or performance. However, when the voltage on the charger side fails to increase due to a circuit / control problem with the charger, both the vehicle's high-voltage battery voltage and the charger voltage remain unchanged. In this situation, charging cannot continue, and charging is terminated. Summary of the Invention

[0009] This disclosure has been proposed to address the problems described in the background section above, and the purpose of this disclosure is to provide a method for switching between fast charging modes, which is capable of changing the fast charging mode after determining an initial charging mode by taking into account the current voltage of the vehicle's high-voltage battery and the output voltage of the charger.

[0010] In addition, another object of this disclosure is to provide a method for switching between fast charging modes, which can ensure charging robustness by changing the fast charging mode according to the situation.

[0011] Furthermore, another object of this disclosure is to provide a method for switching between fast charging modes, which can improve charging performance and / or efficiency by reducing the voltage rise switching of the boost converter.

[0012] To achieve the above objectives, this disclosure provides a method for switching between fast charging modes, which can change the fast charging mode after determining an initial charging mode by taking into account the current voltage of the vehicle's high-voltage battery and the output voltage of the charger.

[0013] The method includes: exchanging information between the charger and the vehicle; based on the information exchange, the vehicle's charging controller compares the maximum voltage of the high-voltage battery with the maximum output voltage of the charger; when the maximum voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller compares the current voltage of the high-voltage battery with the maximum output voltage of the charger; when the current voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller enters a boost charging mode; and when the current voltage of the high-voltage battery is equal to or less than the maximum output voltage of the charger, the charging controller enters a direct charging mode.

[0014] The method may further include: when the maximum voltage of the high-voltage battery is equal to or less than the maximum output voltage of the charger, causing the charging controller to enter a direct charging mode to compare the current voltage of the high-voltage battery with the actual output voltage of the charger, and based on the comparison result, maintaining the direct charging mode or changing the direct charging mode to a boost charging mode.

[0015] This change may include: when the current voltage of the high-voltage battery is equal to or greater than the actual output voltage of the charger, the charging controller uses the vehicle current command transmitted to the charger and the charger output current from the charger to change the direct charging mode to the boost charging mode.

[0016] Changing from direct charging mode to boost charging mode may include: the charging controller setting the vehicle current command to the minimum supply current of the charger; the charging controller comparing whether the vehicle current command and the charger output current are the same; and when the comparison result shows that the vehicle current command and the charger output current are the same, changing the direct charging mode to boost charging mode.

[0017] Changing from direct charging mode to boost charging mode can include increasing the vehicle current command to the initial value after the charging controller changes the direct charging mode to boost charging mode.

[0018] When the minimum supply current of the charger is not provided, the vehicle current command can be set to the preset current.

[0019] This change could include: when the current voltage of the high-voltage battery is lower than the actual output voltage of the charger, the charging controller maintains the direct charging mode.

[0020] Entering direct charging mode may include: the charging controller comparing the current voltage of the high-voltage battery with a pre-calculated limit voltage, and maintaining direct charging mode or changing direct charging mode to boost charging mode based on the comparison result.

[0021] This change may include: when the current voltage of the high-voltage battery is equal to or greater than the limit voltage, the charging controller uses the vehicle current command and the charger output current from the charger to change the direct charging mode to the boost charging mode.

[0022] In this case, the limiting voltage can be the product of the charger's maximum output voltage and a specific ratio.

[0023] This change could include: when the current voltage of the high-voltage battery is less than the limit voltage, the charging controller maintains the direct charging mode.

[0024] When the high-voltage battery enters the boost charging mode when its current voltage is greater than the charger's maximum output voltage, this boost charging mode can be maintained until charging is complete.

[0025] The boost charging mode can be operated using a separate boost converter installed in the vehicle or a drive block in the vehicle that includes a motor and an inverter.

[0026] When entering direct charging mode, the initial charging mode can be direct charging mode.

[0027] According to this disclosure, compared with the method of determining the boost charging mode or the direct charging mode by comparing only the maximum voltage of the vehicle's high-voltage battery and the maximum output voltage of the charger, changing the charging mode after determining the initial charging mode by taking into account the current voltage of the vehicle's high-voltage battery and the output voltage of the charger can improve charging performance and / or charging robustness.

[0028] Furthermore, according to this disclosure, even when the charger output voltage cannot rise above the current voltage of the vehicle's high-voltage battery due to problems with the charger's circuitry / control, the vehicle can be fully charged by switching from direct charging mode to boost charging mode, thus improving charging robustness.

[0029] Furthermore, according to this disclosure, when the maximum voltage of the vehicle's high-voltage battery > the maximum voltage of the charger > the current voltage of the vehicle's high-voltage battery, when the vehicle is operating in direct charging mode until boost charging can be performed, switching from direct charging mode to boost charging mode can reduce the voltage rise switching of the boost converter, thereby improving charging performance / efficiency. Attached Figure Description

[0030] Figure 1 This is a conceptual diagram of a vehicle charging system according to an embodiment of the present disclosure.

[0031] Figure 2A Is Figure 1 A detailed block diagram of the insulation structure boost charging method implemented in the vehicle shown.

[0032] Figure 2B Is Figure 1 A detailed block diagram of the non-insulated structure boost charging method implemented in the vehicle is shown.

[0033] Figure 3 It is shown Figure 2A or Figure 2B A diagram illustrating the concept of the charging controller configured in the system determining the initial charging entry mode and the final charging switching mode.

[0034] Figure 4A and Figure 4B This is a flowchart illustrating the process of switching between fast charging modes according to an embodiment of the present disclosure.

[0035] Figure 5 This is a conceptual diagram illustrating the switching between fast charging modes when the maximum voltage of the vehicle's high-voltage battery is less than the maximum output voltage of the charger, according to one embodiment of this disclosure.

[0036] Figure 6 This is a conceptual diagram illustrating the switching between fast charging modes when the maximum voltage of the vehicle's high-voltage battery is greater than the maximum output voltage of the charger, according to one embodiment of this disclosure.

[0037] Figure 7 This is a conceptual diagram of boost charging according to an embodiment of the present disclosure.

[0038] Figure 8 This is a conceptual diagram of series charging according to an embodiment of the present disclosure. Detailed Implementation

[0039] The above-described objects, features, and advantages are described in detail below with reference to the accompanying drawings. Therefore, those skilled in the art to which this disclosure pertains can readily practice the technical concept of this disclosure. In interpreting this disclosure, detailed descriptions of known technologies related to this disclosure will be omitted where it is determined that such detailed descriptions might unnecessarily obscure the main points of this disclosure.

[0040] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0041] Figure 1 This is a conceptual diagram of a vehicle charging system 100 according to an embodiment of the present disclosure. (Refer to...) Figure 1 The vehicle charging system 100 includes a charger 110, a vehicle 120, etc. The charger 110 supplies charging power, and the vehicle 120 receives charging power from the charger 110. The charger 110 may be configured with a connection connector 101, and charging can be performed by connecting the connection connector 101 to the charging port 121 of the vehicle 120.

[0042] Charger 110 may be an Electric Vehicle Supply Equipment (EVSE). Charger 110 may be configured to include a charging unit 111, a control unit 112, etc. The charging unit 111 generates charging power, particularly DC charging power, and the control unit 112 controls the charging unit 111 and performs communication with the vehicle 120.

[0043] The charging unit 111 performs the functions of receiving AC power, converting AC power into DC charging power, and supplying DC charging power to the vehicle 120. For this purpose, the charging unit 111 may include circuitry such as an AC-DC converter and regulator, as well as a control program.

[0044] The control unit 112 controls the charging unit 111 and performs the function of communicating with the vehicle 120 and / or an external network. For this purpose, the control unit 112 may include a microprocessor, a microcomputer, communication circuitry, memory, a display, input devices, etc. The display may be a touchscreen, etc. Therefore, both input and output devices are feasible. The input device may be a button, microphone, etc.

[0045] Vehicle 120 includes a charging port 121 that connects to a connector 101 of charger 110. Accordingly, connector 101 and charging port 121 can be configured using any of the Combined Charging System 1 (CCS1), Combined Charging System 2 (CCS2), and North American Charging Standard (NACS) methods.

[0046] Figure 2A Is Figure 1 A detailed block diagram of the insulation structure boost charging method implemented in the vehicle 120 shown. (Refer to...) Figure 2A The vehicle 120 may include a charging controller 210, a boost converter 220, a drive block 230, a battery 240, etc. Here, the insulated structure boost charging method refers to the method of using a separate boost converter 220 to boost the voltage.

[0047] The charging controller 210 is connected to communicate with the control unit 112 of the charger 110, and the charger 110 is connected to communicate with the charging controller 210 via a control pilot (CP) line. Accordingly, the charging controller 210 and the control unit 112 send and receive data related to fast charging by using PLC communication on the CP signal for fast charging.

[0048] Furthermore, the charging controller 210 performs the functions of the control components, namely the boost converter 220, the drive block 230, and the battery 240. Specifically, the charging controller 210 determines the initial charging mode by considering the current voltage of the high-voltage battery and the output voltage of the charger, and executes a control algorithm for switching between fast charging modes. For this purpose, the charging controller 210 may include a microcomputer, a microprocessor, electronic circuits, communication circuits, memory, etc.

[0049] The memory may include non-volatile memory and / or a combination of volatile memory. Non-volatile memory includes, for example, flash memory disks (SSDs), hard disk drives, flash memory, electrically erasable programmable read-only memory (EEPROM), static RAM (SRAM), ferroelectric RAM (FRAM), phase-change RAM (PRAM), and magnetic RAM (MRAM). Volatile memory includes, for example, dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), and double data rate SDRAM (DDR-SDRAM).

[0050] The boost converter 220 is configured separately in the vehicle and performs the switching for voltage boosting. For this purpose, switching elements, inductors, diodes, capacitors, resistors, etc., can be configured, such as... Figure 7 and Figure 8 As shown. This will be described later.

[0051] The boost converter 220 forms a charging path 201 from the charger 110 to the battery 240 via the charging port 121. That is, the first charging path 201 is formed in the order of charging port 121, boost converter 220, and battery 240. Boost charging or direct charging is performed through this charging path 201. Boost charging is performed by increasing the voltage according to the boost converter 220, and for example, approximately 400V of power supplied from the charger 110 can be boosted to approximately 800V and supplied to the battery 240.

[0052] Direct charging is a form in which the switching element in the boost converter 220 remains in the off state and the charger 110 and battery 240 are directly connected without increasing the voltage.

[0053] The drive block 230 includes a motor 231 and an inverter 232, which operates the motor 231. The motor 231 is primarily a three-phase alternating current (AC) motor. The inverter 232 performs the function of converting DC power from the battery 240 into AC power and supplying the converted AC power to the motor 231.

[0054] exist Figure 2A In the diagram, the motor 231 and the inverter 232 are shown separately, but they can be integrated and configured as a single unit. That is, the inverter 232 can be integrated into the motor 231.

[0055] Battery 240 includes battery cells (not shown) connected in series and / or parallel, and the battery cells can be high-voltage battery cells for electric vehicles, such as nickel-metal hydride battery cells, lithium-ion battery cells, lithium polymer battery cells, lithium-sulfur battery cells, sodium-sulfur battery cells, and all-solid-state battery cells. Typically, high-voltage batteries are batteries used as a power source to power electric vehicles and refer to high voltages of 100V or higher. However, this is not the only possibility; low-voltage batteries are also feasible.

[0056] Battery 240 may include a battery management system (BMS) 241. BMS 241 optimizes battery management for electric vehicles to improve energy efficiency and extend battery life. BMS 241 monitors battery voltage, current, and temperature in real time and prevents overcharging and discharging in advance to improve battery safety and reliability.

[0057] Figure 2B Is Figure 1 A detailed block diagram of the non-insulated structure boost charging method implemented in the vehicle is shown. (Refer to...) Figure 2B The vehicle 120 may include a charging controller 210, a drive block 230, a battery 240, etc. Here, the non-insulated structure boost charging method refers to a method of boosting voltage by using a drive block 230 including a motor 231 and an inverter 232 without using a separate boost converter 220.

[0058] Therefore, the second charging path 202 is formed in the order of charging port 121, drive block 230 and battery 240.

[0059] Boost charging or direct charging is performed through charging path 202. Boost charging is performed by increasing the voltage according to drive block 230. For example, approximately 400V of power supplied from charger 110 is boosted to approximately 800V and supplied to battery 240.

[0060] Direct charging is a form in which the switching element in the boost converter 220 remains in the off state and the charger 110 and battery 240 are directly connected without increasing the voltage.

[0061] Figure 3 It is shown Figure 2A or Figure 2B A diagram illustrating the concept of the charging controller 210 configured in the middle determining the initial charging entry mode and the final charging switching mode. (Refer to...) Figure 3 The charging controller 210 can utilize a total of four types of power information: 1) the maximum voltage of the high-voltage battery 310; 2) the maximum output voltage of the charger 320; 3) the current voltage of the high-voltage battery 330; and 4) the actual output voltage of the charger 340.

[0062] 1) The maximum voltage of the high-voltage battery is 310, which refers to the maximum voltage at which the battery 240 can be charged.

[0063] 2) The maximum output voltage of the charger is 320V, which refers to the maximum rechargeable voltage provided by the charger's 110 side.

[0064] 3) The current voltage of the high-voltage battery 330 refers to the voltage at which the battery 240 is currently being charged.

[0065] 4) The actual output voltage 340 of the charger refers to the actual voltage output by the charger during charging. The actual output voltage 340 of the charger can be provided to the vehicle 120 side in real time from the charger 110 side, or it can be generated using a voltage sensor (not shown) on the charger 110 side.

[0066] Using these four pieces of information, the fast charging mode, the initial charging mode, and the final charging switching mode (350) are determined. This can be explained in the following easy-to-understand way.

[0067] a) Maximum voltage of high-voltage battery 310 < maximum output voltage of charger 320

[0068] The charging controller 210 enters the direct charging mode as the initial charging mode.

[0069] Meanwhile, when the charger fails to charge due to circuit / control problems in the charger 110 during fast charging in direct charging mode, the direct charging mode is changed to boost charging mode.

[0070] b) When the maximum voltage of the high-voltage battery 310 > the maximum output voltage of the charger 320, the charging controller 210 enters the boost charging mode as the final charging mode.

[0071] The charger's maximum output voltage of 320V is compared with the current voltage of the high-voltage battery of 330V to determine which charging mode to enter.

[0072] b-1) When the charger's maximum output voltage 320V > the current voltage of the high-voltage battery 330V, the charging controller 210 enters the direct charging mode.

[0073] When the battery 240 is being charged and the voltage rises to the limit voltage (i.e., the charger's maximum output voltage × a specific ratio), the charging controller 210 changes the direct charging mode to the boost charging mode.

[0074] b-2) When the charger's maximum output voltage of 320V is less than the current voltage of the high-voltage battery of 330V, the charging controller 210 enters the boost charging mode.

[0075] Figure 4A and Figure 4B This is a flowchart illustrating the process of switching between fast charging modes according to an embodiment of the present disclosure. Figure 4A and Figure 4B As illustrated in the diagram, when the maximum voltage of the high-voltage battery (310V) is greater than the maximum output voltage of the charger (320V), it is determined whether to enter the boost charging mode. Conversely, when the maximum voltage of the high-voltage battery (310V) is less than the maximum output voltage of the charger (320V), it is determined whether to enter the direct charging mode.

[0076] First, refer to Figure 4A When the charger 110 and vehicle 120 are connected and fast charging begins, information is exchanged between the control unit 112 of the charger 110 and the charging controller 210 of the vehicle 120 (step S410). Specifically, the control unit 112 transmits charger-related information to the charging controller 210, and the charging controller 210 transmits battery-related information to the control unit 112 of the charger 110.

[0077] Charger-related information may include details such as: maximum output voltage, actual output voltage, output current, minimum supply current, power, and MAC address. Battery-related information may include the maximum voltage of the high-voltage battery, its current voltage, and its state of charge (SOC). Here, SOC can also represent the amount of charge.

[0078] Subsequently, the charging controller 210 compares the maximum voltage 310 of the high-voltage battery and the maximum output voltage 320 of the charger based on information exchange to confirm whether the maximum voltage 310 of the high-voltage battery is greater than the maximum output voltage 320 of the charger (step S420).

[0079] In step S420, when the maximum voltage of the high-voltage battery 310 is greater than the maximum output voltage of the charger 320, the charging controller 210 compares the current voltage of the high-voltage battery 330 with the maximum output voltage of the charger 320 to confirm whether the current voltage of the high-voltage battery 330 is greater than the maximum output voltage of the charger 320 (steps S430 and S440).

[0080] In other words, even when the maximum voltage of the high-voltage battery 310 is greater than the maximum output voltage of the charger 320, the charging mode will not immediately enter the boost charging mode. Instead, the maximum output voltage of the charger 320 and the current voltage of the high-voltage battery 330 are compared to determine whether to enter the initial charging mode.

[0081] In step S440, as a result of the comparison, when the current voltage 330 of the high-voltage battery is greater than the maximum output voltage 320 of the charger, the charging controller 210 enters the boost charging mode and maintains the boost charging mode until the charging is completed (step S450).

[0082] At this point, boost charging mode can be operated by using a separate boost converter 220 in a vehicle equipped with a boost converter 220. Of course, in a vehicle not equipped with a separate boost converter 220, boost charging mode can be operated by using a drive block 230 including a motor 231 and an inverter 232.

[0083] Meanwhile, in boost charging mode, there may be a range where the current voltage of the high-voltage battery (330V) is lower than the charger's maximum output voltage (320V), and within this range, direct charging mode can be entered. When this range occurs in boost charging mode, the boost converter 220 or the driver block 230 performs a switch to increase the voltage.

[0084] However, overall charging efficiency and performance are reduced due to power consumption. Charging performance and / or efficiency can be improved compared to existing charging performance and / or efficiency when using direct charging mode within the corresponding range.

[0085] Reference Figure 4B ,exist Figure 4A In step S420, when the maximum voltage of the high-voltage battery 310 is lower than or equal to the maximum output voltage of the charger 320, the charging controller 210 enters the direct charging mode (step S421).

[0086] In direct charging mode, charging power is supplied directly from charger 110 to battery 240 without a boost process, thereby performing charging. In direct charging mode, since there is no switching operation for voltage increase in boost converter 220 or drive block 230 compared to boost charging mode, there is an advantage in improved charging efficiency and / or charging performance.

[0087] However, when the voltage on the charger side cannot be increased due to a circuit / control problem with the charger 110, the high-voltage battery voltage of the vehicle 120 and the charger voltage remain the same, so charging cannot continue and may be terminated.

[0088] In this case, when changing from direct charging mode to boost charging mode, the vehicle can be fully charged without interrupting the charging process by increasing the voltage in boost converter 220 or drive block 230.

[0089] To put it simply, when the direct charging mode is in operation, if the charger voltage does not rise above the high-voltage battery voltage due to a circuit / control problem with the charger 110, the charging in the vehicle is not terminated by utilizing the charger-related information provided by the charger 110 side.

[0090] The fast charging mode switches from the direct charging mode to the boost charging mode, and the voltage is increased in the boost converter 220 or the drive block 230 to fully charge the battery 240.

[0091] Reference Figure 4B The charging controller 210 confirms whether the current voltage 330 of the high-voltage battery is equal to or greater than the actual output voltage 340 of the charger (step S460).

[0092] In step S460, as a confirmation result, when the current voltage 330 of the high-voltage battery is equal to or greater than the actual output voltage 340 of the charger, the charging controller 210 sets the vehicle current command to the minimum supply current of the charger (step S471).

[0093] In other words, this setting reduces the charging current command to the charger's minimum supply current, ensuring no issues arise during charging mode switching and allowing the charging mode to switch at the lowest possible charging current that the charger can supply. When no information on the charger's minimum supply current is provided, the charging controller 210 sets the vehicle current command to a preset current (e.g., 0A).

[0094] Subsequently, the charging controller 210 compares and confirms the vehicle current command transmitted to the charger 110 with the charger output current from the charger 110 (step S480). In other words, the charging controller confirms whether the vehicle current command is the same as or similar to the charger output current. That is, there is a certain error range. For example, the error range can be approximately ±5%.

[0095] In step S480, when the vehicle current command is almost the same as the charger output current, the charging controller 210 changes the direct charging mode to the boost charging mode and enters the boost charging mode (step S490).

[0096] Conversely, in step S480, if the vehicle current command is not equal to the charger output current, steps S471 to S480 are executed again.

[0097] Meanwhile, in step S460, when the current voltage of the high-voltage battery 330 is less than the actual output voltage of the charger 340, step S421 is executed again. That is, the charging controller 210 maintains the direct charging mode.

[0098] Reference Figure 4B ,existFigure 4A In step S440, when the current voltage 330 of the high-voltage battery is equal to or less than the maximum output voltage 320 of the charger, the charging controller 210 enters the direct charging mode (step S441).

[0099] Subsequently, the charging controller 210 compares the current voltage 330 of the high-voltage battery with the limiting voltage (step S470). Here, the limiting voltage can be pre-calculated as the charger's maximum output voltage multiplied by a specific ratio.

[0100] In step S470, as a result of confirmation, when the current voltage 330 of the high-voltage battery is equal to or greater than the limit voltage, the charging controller 210 sets the vehicle current command to the minimum supply current of the charger (step S471).

[0101] Subsequently, the charging controller 210 compares and confirms the vehicle current command and the charger output current from the charger 110 (step S480).

[0102] In step S480, when the vehicle current command is almost the same as the charger output current, the charging controller 210 changes the direct charging mode to the boost charging mode and enters the boost charging mode (step S490). Specifically, when the high-voltage battery is being charged at its current voltage 330 and the voltage increases to the charger's maximum output voltage × a specific ratio, the charging controller 210 switches from the direct charging mode to the boost charging mode.

[0103] Conversely, in step S480, if the vehicle current command is not equal to the charger output current, steps S471 to S480 are executed again.

[0104] Meanwhile, in step S470, when the current voltage 330 of the high-voltage battery is less than the limit voltage, step S441 is executed again. That is, the charging controller 210 maintains the direct charging mode.

[0105] Figure 5 This is a conceptual diagram illustrating the switching between fast charging modes when the maximum voltage of the vehicle's high-voltage battery is less than the maximum output voltage of the charger, according to one embodiment of this disclosure. (See also...) Figure 5 The following lines are shown in sequence: 510 representing the current voltage of the high-voltage battery, 520 representing the actual maximum operating voltage of the charger, 530 representing the maximum voltage of the high-voltage battery, and 540 representing the maximum operating voltage of the charger.

[0106] Fast charging begins with direct charging mode as the initial charging mode. During this period, no charging mode switching should be used. Because the actual output voltage of the charger does not increase, the current voltage of the vehicle's high-voltage battery and the charger's output voltage are almost the same.

[0107] Therefore, the vehicle current command transmitted from vehicle 120 to charger 110 is reduced to the charger's minimum output current. Of course, when there is no minimum supply current information provided by the charger side, the vehicle current command is set to a preset current (e.g., 0A).

[0108] After confirming that the charger output current (i.e., vehicle current command ≒ charger output current) has been reduced according to the vehicle current command in the charger 110, the charging controller 210 changes the direct charging mode to the boost charging mode by turning on / off the switching element of the boost converter 220 or the drive block 230.

[0109] After switching to boost charging mode, the vehicle current command, which was reduced to change the charging mode, is raised back to its initial value.

[0110] Figure 6 This is a conceptual diagram illustrating the switching between fast charging modes according to an embodiment of this disclosure when the maximum voltage of the vehicle's high-voltage battery is greater than the maximum output voltage of the charger. (Refer to...) Figure 6 The straight line 610 representing the current voltage of the high-voltage battery, the straight line 620 representing the maximum voltage of the charger, and the straight line 630 representing the maximum voltage of the high-voltage battery are shown below in sequence.

[0111] Reference Figure 6 When the maximum voltage of the vehicle's high-voltage battery is greater than the maximum output voltage of the charger, and the current voltage of the vehicle's high-voltage battery is greater than the maximum output voltage of the charger, the charging controller 210 enters the boost charging mode as the initial charging entry mode and maintains the boost charging mode until charging is completed. In this case, the switching element of the boost converter 220 is turned on / off.

[0112] Simultaneously, when the maximum voltage of the vehicle's high-voltage battery is greater than the maximum output voltage of the charger, and the current voltage of the vehicle's high-voltage battery is less than the maximum output voltage of the charger, the charging controller enters the direct charging mode as the initial charging entry mode. In this case, the switching element of the boost converter 220 or the drive block 230 remains in the off state.

[0113] In this state, when the battery 240 is being charged and the current voltage of the high-voltage battery rises to the limit voltage (i.e., the charger's maximum output voltage × a specific ratio), preparation is made to change from the direct charging mode to the boost charging mode.

[0114] The charging current command transmitted from vehicle 120 to charger 110 is reduced to the charger's minimum supply current. When there is no information on the minimum supply current provided by the charger side, it is set to 0A.

[0115] After confirming that the charging controller 210 has reduced the charger output current according to the vehicle current command from the charger 110, the charging mode is changed to boost charging mode by performing an on / off operation on the switching element of the boost converter 220 or the drive block 230.

[0116] After switching to boost charging mode, the charging controller 210 will command the vehicle current, which was reduced to change the charging mode, to rise back to the initial value.

[0117] For charger 110 to charge, the charger output voltage should always be higher than the vehicle's high-voltage battery voltage. When battery 240 is charging, the current voltage increases, and when the battery voltage increases to near the charger's maximum operating voltage with almost no voltage difference, the charger may be unable to charge. Therefore, instead of using the actual maximum charger voltage, a specific percentage is applied to switch to boost charging mode when the voltage is below the maximum.

[0118] Figure 7 This is a conceptual diagram of boost charging according to an embodiment of the present disclosure. Specifically, Figure 7 This is the equivalent circuit diagram of the 220 boost converter. (Refer to...) Figure 7 When switching element T R When the circuit is turned on, the charging voltage V from charger 110 is... l It is stored in inductor L.

[0119] Switching element T R It can be a semiconductor switching element, such as a field-effect transistor (FET), a metal-oxide-semiconductor FET (MOSFET), an insulated-gate bipolar transistor (IGBT), a power rectifier diode, a thyristor, a gate-to-turn (GTO) thyristor, a triac, a silicon controlled rectifier (SCR), an integrated circuit (IC), etc.

[0120] Specifically, for semiconductor devices, bipolar, power metal-oxide-semiconductor field-effect transistors (MOSFETs) can be used. Unlike ordinary MOSFETs, power MOSFETs have a double-diffused metal-oxide-semiconductor (DMOS) structure due to their high voltage and high current operation.

[0121] After energy is stored in inductor L, when switching element T... R When the circuit is switched off again, the charging voltage increases the amount of energy stored in the inductor L to charge the battery 240. That is, the voltage V generated across the resistor R connected in parallel with the capacitor C increases. O Charge battery 240. This can be done at switching element T. R A diode D is placed between the capacitor C and the capacitor to prevent reverse current.

[0122] Figure 8 This is a conceptual diagram of direct charging according to an embodiment of the present disclosure. (Refer to...) Figure 8 In the case of direct charging, switching element T R Keep it in the off state so that the charging voltage V l A uniform voltage V is generated across resistor R. O And it is supplied to battery 240. That is to say, there is no boost process through inductor L.

[0123] exist Figure 7 and Figure 8 In this example, the boost converter 220, which is separately installed in vehicle 120, is used as an example to explain the concepts of boost charging and direct charging. However, the drive block 230, which includes motor 231 and inverter 232, also has a similar equivalent circuit diagram. In other words, by connecting the charger 110 according to the neutral terminal of motor 231 and controlling the on / off state of the inductor in motor 231 and the switching element in inverter 232, it can operate like a boost converter.

[0124] Since the boost technology using a motor and inverter is disclosed in Korean Patent Publication No. 10-2023-0000334 filed by the same applicant, further description of it will be omitted.

[0125] Furthermore, the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented in the form of program instructions, which can be executed by various computer devices such as microprocessors, processors, and central processing units (CPUs) and recorded on a computer-readable medium. The computer-readable medium may include, individually or in combination, program (instruction) code, data files, data structures, etc.

[0126] While this disclosure has been described above with reference to exemplary accompanying drawings, it is not limited to the described embodiments, and it will be apparent to those skilled in the art that various modifications and alterations can be made without departing from the spirit and scope of this disclosure. Therefore, examples of such modifications or alterations should be included in the claims of this disclosure, and the scope of this disclosure should be interpreted based on the appended claims.

Claims

1. A method for switching between fast charging modes, the method comprising: Exchange information between the charger and the vehicle; Based on the exchange of the information, the vehicle's charging controller compares the maximum voltage of the high-voltage battery with the maximum output voltage of the charger; When the maximum voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller compares the current voltage of the high-voltage battery with the maximum output voltage of the charger; When the current voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller enters the boost charging mode. as well as When the current voltage of the high-voltage battery is equal to or less than the maximum output voltage of the charger, the charging controller enters the direct charging mode.

2. The method according to claim 1, further comprising: When the maximum voltage of the high-voltage battery is equal to or less than the maximum output voltage of the charger, the charging controller enters the direct charging mode to compare the current voltage of the high-voltage battery with the actual output voltage of the charger, and based on the comparison result, maintains the direct charging mode or changes the direct charging mode to the boost charging mode.

3. The method according to claim 2, wherein, The change includes: when the current voltage of the high-voltage battery is equal to or greater than the actual output voltage of the charger, the charging controller uses the vehicle current command transmitted to the charger and the charger output current from the charger to change the direct charging mode to the boost charging mode.

4. The method according to claim 3, wherein, Changing the direct charging mode to the boost charging mode includes: The charging controller sets the vehicle current command to the minimum supply current of the charger. The charging controller compares whether the vehicle current command and the charger output current are the same; and When the vehicle current command and the charger output current are the same as the result of the comparison, the direct charging mode is changed to the boost charging mode.

5. The method according to claim 4, wherein, Changing the direct charging mode to the boost charging mode includes: after the charging controller changes the direct charging mode to the boost charging mode, increasing the vehicle current command to the initial value.

6. The method according to claim 3, wherein, When no information about the minimum supply current of the charger is provided, the vehicle current command is set to the preset current.

7. The method according to claim 2, wherein, The change includes: when the current voltage of the high-voltage battery is less than the actual output voltage of the charger, the charging controller maintains the direct charging mode.

8. The method according to claim 1, wherein, Entering the direct charging mode includes: the charging controller comparing the current voltage of the high-voltage battery with a pre-calculated limit voltage, and based on the comparison result, maintaining the direct charging mode or changing the direct charging mode to the boost charging mode.

9. The method according to claim 8, wherein, The change includes: when the current voltage of the high-voltage battery is equal to or greater than the pre-calculated limit voltage, the charging controller uses a vehicle current command and the charger output current from the charger to change the direct charging mode to the boost charging mode.

10. The method according to claim 8, wherein, The pre-calculated limiting voltage is the product of the charger's maximum output voltage and a specific ratio.

11. The method according to claim 8, wherein, The change includes: when the current voltage of the high-voltage battery is less than the pre-calculated limit voltage, the charging controller maintains the direct charging mode.

12. The method according to claim 1, wherein, When the current voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the boost charging mode is maintained until the charging is completed.

13. The method according to claim 1, wherein, The boost charging mode is operated using a separate boost converter installed in the vehicle or a drive block in the vehicle that includes a motor and an inverter.

14. The method according to claim 1, wherein, When entering the direct charging mode, the initial charging mode is the direct charging mode.

15. A system for switching between fast charging modes, the system comprising: One or more processors; as well as One or more memory devices storing programming code, the programming code including instructions that, when the one or more processors execute the instructions, cause the one or more processors to: Exchange information between the charger and the vehicle; The vehicle's charging controller performs a first comparison between the maximum voltage of the high-voltage battery and the maximum output voltage of the charger based on the exchanged information; When the maximum voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller performs a second comparison between the current voltage of the high-voltage battery and the maximum output voltage of the charger. When the current voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller enters the boost charging mode. and When the current voltage of the high-voltage battery is equal to or less than the maximum output voltage of the charger, the charging controller enters the direct charging mode.

16. The system according to claim 15, wherein, The one or more processors execute the instructions to further cause the one or more processors to: When the maximum voltage of the high-voltage battery is equal to or less than the maximum output voltage of the charger, the charging controller enters the direct charging mode. Perform a third comparison between the current voltage of the high-voltage battery and the actual output voltage of the charger; and Based on the result of the third comparison, the direct charging mode is maintained or the direct charging mode is changed to the boost charging mode.

17. The system according to claim 16, wherein, In order to change the direct charging mode to the boost charging mode, the one or more processors execute the instructions to further cause the one or more processors to: When the current voltage of the high-voltage battery is equal to or greater than the actual output voltage of the charger, the charging controller uses the vehicle current command transmitted to the charger and the charger output current from the charger.

18. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors, cause the one or more processors to: The charger exchanges information with the vehicle, which includes the one or more processors; The charging controller of the vehicle, running on the one or more processors, performs a first comparison between the maximum voltage of the high-voltage battery and the maximum output voltage of the charger based on the exchanged information. When the maximum voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller performs a second comparison between the current voltage of the high-voltage battery and the maximum output voltage of the charger. When the current voltage of the high-voltage battery is greater than the maximum output voltage of the charger, the charging controller enters the boost charging mode. and When the current voltage of the high-voltage battery is equal to or less than the maximum output voltage of the charger, the charging controller enters the direct charging mode.

19. The non-transitory computer-readable medium according to claim 18, wherein, In order to enter the direct charging mode, the one or more processors execute the instructions to further enable the one or more processors to: The charging controller performs a third comparison between the current voltage of the high-voltage battery and a pre-calculated limit voltage; and Based on the result of the third comparison, the direct charging mode is maintained or the direct charging mode is changed to the boost charging mode.

20. The non-transitory computer-readable medium according to claim 19, wherein, In order to change the direct charging mode to the boost charging mode, the one or more processors execute the instructions to further cause the one or more processors to: When the current voltage of the high-voltage battery is equal to or greater than the pre-calculated limit voltage, the charging controller uses the vehicle current command and the charger output current from the charger.

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