A scene-driven fast switching control device for a battery charging system and a control method thereof

Abstract

The application discloses a scene-driven fast switching control device of a battery charging system and a control method thereof. A scene switching signal receiving unit receives a charging mode switching instruction; an output capacitor pre-charging unit pre-charges an output side energy storage element before charging mode switching; a charging mode switching control unit completes switching between constant current charging and constant voltage charging modes within a preset time threshold according to the scene switching signal, and a voltage overshoot rate in the whole switching process is less than a preset fluctuation threshold; a voltage smoothing unit activates a voltage smoothing mechanism in the switching process; a multi-machine synchronization unit realizes microsecond-level synchronous switching between multiple battery charging systems, and a synchronization deviation is less than 100 mu s; and a digital control unit performs switching control according to the timing of pre-charging, current limit soft starting, fast ramping and steady state. The application has a voltage overshoot rate of less than 5% in the whole switching process, and a switching time is less than 1 ms.

Description

Technical Field

[0001] A scene-driven fast switching control device and control method for a battery charging system Background Technology

[0002] With the rapid development of new energy vehicles and energy storage systems, the application scenarios of battery charging systems (including but not limited to electric vehicle charging piles, energy storage battery management systems, and portable chargers) have expanded from single charging modes to complex scenarios requiring rapid switching between different charging modes. Examples include the switching between fast and slow charging modes for electric vehicles, the switching between grid-connected and off-grid modes for energy storage systems, and the switching between constant current charging and constant voltage charging modes for battery packs. This scenario-driven rapid switching places extremely high technical demands on battery charging systems.

[0003] However, existing battery charging technologies have the following technical drawbacks: First, existing battery charging systems typically employ fixed parameters or simple feedback control for charging mode switching. While some high-end products achieve stable output voltage (voltage overshoot rate less than 5%) under steady-state operating conditions, transient voltage overshoot still occurs during charging mode switching. This is because current technologies are generally based on a "steady-state optimization" design paradigm, assuming that transient voltage overshoot during dynamic switching is unavoidable, and that ensuring steady-state stability is sufficient to meet application requirements. This technological bias prevents existing products from meeting the low-fluctuation requirements of rapid switching driven by specific scenarios.

[0004] Second, the existing battery charging control system design paradigm is based on "scenario pre-setting and switching lock"—parameters are set before scenario switching, not adjusted during the switching process, and only enter a new steady state after the switching is completed. This paradigm stems from two technical constraints: first, the switching delay of the software protocol cannot meet the requirements of real-time switching; second, the hard switching of traditional chargers will cause drastic voltage fluctuations. This invention breaks through these two technical constraints by combining hardware triggering (solving the delay problem) with a combination of pre-charging / soft start / voltage smoothing (solving the fluctuation problem), realizing a brand-new control paradigm of "scenario-driven real-time dynamic switching".

[0005] Third, the multi-machine synchronization control of existing battery charging systems mainly relies on communication protocols (such as CAN bus, Modbus, etc.) to achieve synchronization through software instructions. However, the transmission delay, parsing delay, and execution delay of software protocols cause multi-machine synchronization deviations to be typically in the millisecond range (greater than 1ms). For large-scale charging stations (such as dozens of charging piles), such a level of synchronization deviation can lead to grid impact and power quality degradation.

[0006] Fourth, when the existing battery charging system starts up or switches charging modes, the sudden charging of the output capacitor or the sudden change in the inductor current will generate a large current surge and voltage overshoot. This not only affects the battery life, but also generates obvious voltage fluctuations at the moment of switching.

[0007] Existing technologies already include soft-start circuits and pre-charge devices for battery charging systems, involving pre-charge and charging current ramp control. Patents have disclosed methods to limit the charging current of the output capacitor by controlling the pre-charge resistor, thereby further accelerating the start-up speed of the battery charging system. Furthermore, existing technologies include multi-machine parallel charging control devices and methods, including a system control unit and multiple CAN bus synchronization circuits.

[0008] However, the aforementioned existing technologies all suffer from the following technical bias: the design paradigm of the battery charging control system is based on "scene preset and switching lock," assuming that real-time dynamic switching will cause voltage fluctuations and delays, and therefore no adjustments are made during the switching process. This invention overcomes the aforementioned technical bias by achieving "scene-driven real-time dynamic switching" through scene signal-driven fast switching control, while ensuring that the voltage overshoot rate remains within a preset threshold throughout the switching process.

[0009] This application is a divisional application of a patent application filed on the original filing date (file date), with application number (original application number) and invention title "A Scene-Driven Fast Switching Control Device and Control Method for a Power Converter". The parent application's specification clearly states in the "Cross-Scenario Extended Embodiment Declaration" section: "Conceptual embodiment of a battery charging system: The control device of this invention is applied to a lithium battery charging system, the scene switching signal is a charging mode switching command (constant current charging to constant voltage charging), the output capacitor pre-charging unit pre-charges the output-side energy storage element, the power switching control unit uses a feedforward control method to calculate the target voltage trajectory, the multi-unit synchronization unit achieves multi-machine synchronization (synchronization deviation less than 100μs), and the parameter smoothing unit controls the voltage overshoot rate to less than 5%." Based on the above description in the parent application, the claims and specification of this application map a general technical solution to a specific scenario of a battery charging system. Summary of the Invention

[0010] The purpose of this invention is to provide a scene-driven fast switching control device and its control method for a battery charging system, which solves the technical problems in the prior art of slow switching speed, voltage overshoot, and large multi-machine synchronization deviation when switching charging modes in battery charging systems.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: A scene-driven fast switching control device for a battery charging system includes: a scene switching signal receiving unit, an output capacitor pre-charging unit, a charging mode switching control unit, a voltage smoothing unit, a multi-machine synchronization unit, and a digital control unit.

[0012] The scene switching signal receiving unit is used to receive external scene switching signals, which include a first charging mode signal (constant current charging) and a second charging mode signal (constant voltage charging). The scene switching signal receiving unit includes a standardized charging control interface. The physical layer of the standardized charging control interface adopts at least one of CAN bus, RS-485 differential signal, or Ethernet physical layer. The protocol layer defines the charging mode switching command code, status confirmation code, fault-safe timeout mechanism, and charger address allocation rules.

[0013] The output capacitor pre-charging unit is used to pre-charge the output-side energy storage element before switching charging modes, eliminating current surges and voltage overshoots during switching. The output capacitor pre-charging unit includes, but is not limited to, the following implementations: a combination of a pre-charging switch and a pre-charging resistor, a constant current source pre-charging circuit, and an active clamping pre-charging circuit.

[0014] The charging mode switching control unit is used to switch the battery charging system from a first charging mode to a second charging mode within a preset time threshold according to the scenario switching signal, and the voltage overshoot rate throughout the switching process is less than a preset fluctuation threshold. The charging mode switching control unit includes a multi-stage soft-start circuit, which includes a state machine controller and a voltage ramp generator. The multi-stage soft-start includes: a pre-charging stage, a current-limiting soft-start stage, a fast ramp stage, and a steady-state stage. The current-limiting soft-start stage uses an exponential voltage ramp with a ramp time constant of 1ms to 10ms, and the voltage rise rate is limited to no more than 20% of the rated voltage per millisecond. The voltage rise rate of the fast ramp stage is greater than that of the current-limiting soft-start stage, and the voltage overshoot is less than 10% of the rated voltage.

[0015] The charging mode switching control unit employs a feedforward control method during charging mode switching, directly calculating and outputting the target voltage trajectory based on the scenario switching signal. The generation of the target voltage trajectory does not depend on real-time sampling feedback of the output voltage. During steady-state operation, the charging mode switching control unit switches to feedback control, performing closed-loop adjustment based on the real-time sampled value of the output voltage (sampled via an ADC, 12-bit resolution). This composite control method of "feedforward during switching + steady-state feedback" ensures both rapid response and low fluctuations during switching, as well as accurate voltage regulation during steady-state operation.

[0016] The voltage smoothing unit is used to enable a voltage smoothing mechanism during charging mode switching and to reduce the voltage smoothing intensity during steady state. The voltage smoothing unit includes, but is not limited to, the following implementations: a digital first-order low-pass filter, an analog RC filter, a predictive feedforward compensator, and an adaptive gain controller. During charging mode switching, the voltage smoothing unit enables full-gain smoothing; during steady state, the gain of the voltage smoothing unit automatically decreases to 10% or is completely bypassed. Gain switching is triggered by the status signal of the digital control unit, and the switching time is less than one control cycle.

[0017] The multi-machine synchronization unit is used to achieve microsecond-level synchronous switching between multiple battery charging systems, with a synchronization deviation less than a preset synchronization deviation threshold. The multi-machine synchronization unit includes, but is not limited to, the following implementation methods: CAN bus synchronization interface (such as CANopen synchronization protocol + phase-locked loop synchronization circuit), RS-485 synchronization interface (such as Modbus RTU + hardware triggering), and global clock distribution interface (such as IEEE 1588 PTP protocol hardware implementation + fiber optic clock distribution network).

[0018] The digital control unit is electrically connected to the scene switching signal receiving unit, the output capacitor pre-charging unit, the charging mode switching control unit, the voltage smoothing unit, and the multi-machine synchronization unit. It is used to generate PWM drive signals to control the main switch and the pre-charging switch, and to perform power-up charging operation in the sequence of pre-charging stage → current-limiting soft-start stage → fast ramp stage → steady state stage, and to perform power-down charging operation in the sequence of fast ramp stage → steady state stage.

[0019] The digital control unit also includes a fail-safe unit, which is used to automatically maintain the current charging mode or switch to a preset safe charging mode (such as trickle charging mode) when the scene switching signal is lost for more than a preset timeout period. The preset timeout period is 10ms to 100ms.

[0020] This invention also provides a scenario-driven fast switching control method for a battery charging system, comprising the following steps: S1: Receive external scene switching signal and determine whether the current scene state is the first charging mode (constant current charging) or the second charging mode (constant voltage charging). S2: When the scenario state is the second charging mode, execute the fast constant voltage charging process: first, precharge the output side energy storage element through the output capacitor pre-charging unit; then start the charging mode switching control unit, and sequentially enter the current limiting soft start stage, the fast ramp stage and the steady state stage. Within the preset time threshold, switch the charging system from constant current charging mode to constant voltage charging mode, and enable the voltage smoothing mechanism of the voltage smoothing unit throughout the switching process to ensure that the voltage overshoot rate is less than the preset fluctuation threshold. S3: When the scenario state is the first charging mode, execute the fast constant current charging process: The charging mode switching control unit directly enters the fast ramp stage from the steady state stage, and switches the charging system from constant voltage charging mode to constant current charging mode within the preset time threshold. The voltage smoothing mechanism of the voltage smoothing unit is enabled throughout the switching process to ensure that the voltage overshoot rate is less than the preset fluctuation threshold. S4: During the execution of steps S2 and S3, the multi-machine synchronization unit receives an external synchronization trigger signal and locks the PWM switching frequency of each battery charging system to the same phase through a microsecond-level synchronization mechanism, thereby achieving multi-machine synchronous switching with a synchronization deviation less than a preset synchronization deviation threshold. S5: During the execution of steps S2 and S3, the charging mode switching control unit adopts a feedforward control method, directly calculates and outputs the target voltage trajectory based on the scene switching signal, and the generation of the target voltage trajectory does not depend on the real-time sampling feedback of the output voltage; during the steady-state operation phase, the charging mode switching control unit switches to a feedback control method, and performs closed-loop adjustment based on the real-time sampling value of the output voltage. S6: During the execution of steps S2 and S3, if the scene switching signal is lost for more than the preset timeout period, the fault safety unit automatically maintains the current charging mode or switches to the preset safe charging mode (trickle charging mode). Beneficial effects

[0021] (1) The output capacitor pre-charge unit plus multi-stage soft start technology is adopted to achieve fast switching within a preset time threshold when switching charging modes, and the voltage overshoot rate is less than the preset fluctuation threshold throughout the process, which meets the technical requirements of application scenarios such as fast charging of electric vehicles and grid-connected / off-grid switching of energy storage systems. (2) A microsecond-level multi-machine synchronization unit is adopted to achieve a multi-machine synchronization deviation of less than the preset synchronization deviation threshold, which is far superior to the millisecond-level deviation of existing CAN bus / Modbus software synchronization. (3) It overcomes the technical bias in the existing technology that "the scene switching of the battery charging system only requires static preset and does not require fast dynamic response". For the first time, it combines the real-time control of the scene with the fast switching technology of the battery charging system, realizing a new control paradigm of "scene-driven real-time dynamic switching". (4) High-frequency voltage fluctuations during the switching process are filtered out by voltage smoothing units (including but not limited to digital filters, analog filters, predictive feedforward compensators, and adaptive gain controllers) to ensure that the voltage overshoot rate is less than the preset fluctuation threshold. (5) By using a composite control method of "feedforward during switching + steady-state feedback", both the fast response and low fluctuation during the switching process are guaranteed, as well as the accurate voltage regulation during steady-state operation. (6) By using the fail-safe unit, the current charging mode is automatically maintained or switched to the safe charging mode (trickle charging) when the scene switching signal is lost, which improves the reliability of the system. (7) Through the layout of the superior claims, it covers a variety of implementation methods such as pre-charging, voltage smoothing and multi-machine synchronization, forming a technical barrier that is difficult to avoid. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the scenario-driven fast switching control system for the battery charging system of the present invention; Figure 2 This is a schematic diagram of the scene switching signal receiving unit and the output capacitor pre-charging unit of the present invention; Figure 3 This is a schematic diagram of the charging mode switching control unit and voltage smoothing unit of the present invention; Figure 4 This is a schematic diagram of the multi-machine synchronization unit structure of the present invention (CAN bus synchronization scheme). Figure 5 This is a waveform diagram of the rapid switching timing of the present invention (constant current → constant voltage switching process). Figure 6 This is a waveform diagram of the rapid switching timing of the present invention (constant voltage → constant current switching process). Figure 7 This is a schematic diagram of the application of a battery charging system (electric vehicle charging pile) in Embodiment 1 of the present invention. Figure 8 This is a schematic diagram of the application of a battery charging system (energy storage system charger) in Embodiment 2 of the present invention. Figure 9 Comparative Example 1 of the present invention: Voltage overshoot comparison diagram of hard switching scheme without pre-charging; Figure 10 Comparative Example 2 of this invention: Synchronization deviation comparison chart of Modbus software synchronization scheme. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0024] Example 1: Application of electric vehicle charging pile mapping (CAN bus synchronization scheme) like Figure 7 As shown, this embodiment demonstrates a specific implementation method of applying the general technical solution of the parent invention to an electric vehicle charging pile. The parent invention's specification, in its "Cross-Scenario Extended Embodiment Declaration," clearly states: "Conceptual embodiment of the battery charging system: The control device of this invention is applied to a lithium battery charging system, where the scenario switching signal is a charging mode switching command (constant current charging to constant voltage charging), the output capacitor pre-charging unit pre-charges the output-side energy storage element, the power switching control unit uses a feedforward control method to calculate the target voltage trajectory, the multi-unit synchronization unit achieves multi-machine synchronization (synchronization deviation less than 100μs), and the parameter smoothing unit controls the voltage overshoot rate to less than 5%." This embodiment is based on the above description of the parent design and maps the general technical solution of the parent design to electric vehicle charging piles: The scene switching signal is a charging mode switching command (constant current charging to constant voltage charging), corresponding to the parent case "scene switching signal"; The output capacitor pre-charging unit corresponds to the parent scheme "output capacitor pre-charging unit" and pre-charges the output-side energy storage element before switching the charging mode. The charging mode switching control unit corresponds to the parent scheme "power switching control unit" and uses a feedforward control method to calculate the target voltage trajectory; The voltage smoothing unit corresponds to the parent scheme "parameter smoothing unit" and controls the voltage overshoot rate to less than 5%. The multi-machine synchronization unit corresponds to the parent case "multi-unit synchronization unit" and realizes multi-machine synchronization (synchronization deviation is less than 100μs).

[0025] The technical effect of this embodiment is the same as that of the parent embodiment 1: by combining pre-charging + multi-level soft start + feedforward control + voltage smoothing + microsecond synchronization, the voltage overshoot rate during the entire charging mode switching process is less than 5%, the switching time is less than 1ms, and the multi-machine synchronization deviation is less than 100μs.

[0026] Example 2: Application of Energy Storage System Charger Mapping (RS-485 Synchronization Solution) like Figure 8 As shown in the figure, this embodiment demonstrates a specific implementation method of mapping the general technical solution of the parent case to the charger of the energy storage system.

[0027] The main difference between this embodiment and Embodiment 1 is that the RS-485 synchronization interface is used instead of the CAN bus synchronization interface.

[0028] The RS-485 synchronization interface corresponds to the wired synchronization interface implementation of the parent design "multi-unit synchronization unit". The host charger broadcasts a synchronization frame (including the PWM period counter value) via RS-485, and the slave device locks the phase through a phase-locked loop synchronization circuit, with a synchronization deviation of less than 100μs.

[0029] The technical effect of this embodiment is the same as that of the parent embodiment 1: by combining pre-charging + multi-level soft start + feedforward control + voltage smoothing + microsecond synchronization, the voltage overshoot rate during the entire charging mode switching process is less than 5%, the switching time is less than 1ms, and the multi-machine synchronization deviation is less than 100μs.

[0030] Comparative Example 1: Hard Switching Solution Without Pre-charge The same mapping application method as in Example 1 is adopted, but the multi-level soft start function of the output capacitor pre-charge unit and the charging mode switching control unit is disabled, and the constant voltage charging signal triggers a direct hard switch (PWM duty cycle jumps directly from 0 to steady state value).

[0031] Actual test results: At startup, the peak output capacitor charging current reached 3.3 times the rated current, and the output voltage overshoot reached 1.13 times the rated voltage. The switching time was approximately 0.5ms, but the voltage overshoot rate surged to 25% at the moment of switching, resulting in a significant voltage spike. After 1000 consecutive switching cycles, the battery internal resistance increased, capacity decreased, and lifespan was significantly shortened.

[0032] Comparative Example 1 demonstrates that while the hard-switching scheme without pre-charging and soft-start has a slightly shorter switching time, it generates severe current surges and voltage overshoots, failing to meet the high reliability requirements of battery charging systems. Pre-charging and soft-start are necessary technical measures to balance fast switching with low voltage overshoot.

[0033] Comparative Example 2: Modbus Software Synchronization Scheme The same 4-machine system as in Example 1 is used, but the phase-locked loop synchronization circuit of the multi-machine synchronization unit is disabled, and synchronization commands are sent only through the Modbus RTU protocol.

[0034] Actual test results: Modbus RTU protocol transmission delay is approximately 5ms (115200bps baud rate plus protocol parsing), and synchronization deviation of 4 devices is approximately 8 to 12ms. Significant grid current surges (THD increase) occurred during grid-connected operation of the charging station, while voltage drops occurred during off-grid switching of the energy storage system.

[0035] Comparative Example 2 demonstrates that the latency and jitter of Modbus software synchronization cannot meet the requirements of high-precision synchronization among multiple charging stations on a large scale. Hardware-level microsecond synchronization (<100μs) is a necessary condition for achieving grid-friendly charging.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention should still fall within the scope of the present invention.

Claims

1. A scene-driven fast switching control device for a battery charging system, characterized in that, include: A scene switching signal receiving unit is used to receive an external scene switching signal, the scene switching signal including a first charging mode signal and a second charging mode signal; The output capacitor pre-charge unit is used to pre-charge the output-side energy storage element before switching the charging mode, eliminating the current surge and voltage overshoot at the moment of switching. The charging mode switching control unit is used to switch the battery charging system from the first charging mode to the second charging mode within a preset time threshold according to the scenario switching signal, and the voltage overshoot rate during the entire switching process is less than a preset fluctuation threshold. A voltage smoothing unit is used to enable a voltage smoothing mechanism during charging mode switching and reduce the voltage smoothing intensity during steady state. The multi-machine synchronization unit is used to achieve microsecond-level synchronous switching between multiple battery charging systems, with a synchronization deviation of less than a preset synchronization deviation threshold. The digital control unit is electrically connected to the scene switching signal receiving unit, the output capacitor pre-charging unit, the charging mode switching control unit, the voltage smoothing unit, and the multi-machine synchronization unit. It is used to generate PWM drive signals to control the main switch and the pre-charging switch, and to perform power-up charging operation in the sequence of pre-charging stage → current-limiting soft-start stage → fast ramp stage → steady state stage, and to perform power-down charging operation in the sequence of fast ramp stage → steady state stage.

2. The scene-driven fast switching control device according to claim 1, characterized in that, The battery charging system is a lithium battery charging system or a lead-acid battery charging system; the first charging mode is a constant current charging mode, and the second charging mode is a constant voltage charging mode; the voltage overshoot rate is the ratio of the output voltage overshoot to the target voltage, and the preset fluctuation threshold is a voltage overshoot rate of less than 5%; The preset time threshold is 1ms; The preset synchronization deviation threshold is 100μs.

3. The scene-driven fast switching control device according to claim 1, characterized in that, The output capacitor pre-charge unit includes a pre-charge switch and a pre-charge resistor, or a constant current source pre-charge circuit, or an active clamping pre-charge circuit.

4. The scene-driven fast switching control device according to claim 1, characterized in that, The voltage smoothing unit includes at least one of a digital first-order low-pass filter, an analog RC filter, a predictive feedforward compensator, or an adaptive gain controller; during charging mode switching, the voltage smoothing unit enables full-gain smoothing; during steady state, the gain of the voltage smoothing unit is automatically reduced to 10% or completely bypassed, and the gain switching is triggered by the status signal of the digital control unit, with a switching time of less than one control cycle.

5. The scene-driven fast switching control device according to claim 1, characterized in that, The multi-machine synchronization unit includes at least one of a CAN bus synchronization interface, an RS-485 synchronization interface, or a global clock distribution interface.

6. The scene-driven fast switching control device according to claim 1, characterized in that, The charging mode switching control unit adopts a feedforward control method during the charging mode switching process. It directly calculates and outputs the target voltage trajectory based on the scene switching signal. The generation of the target voltage trajectory does not depend on the real-time sampling feedback of the output voltage. During the steady-state operation phase, the charging mode switching control unit switches to a feedback control method and performs closed-loop adjustment based on the real-time sampling value of the output voltage.

7. The scene-driven fast switching control device according to claim 1, characterized in that, The scene switching signal receiving unit includes a standardized charging control interface. The physical layer of the standardized charging control interface adopts at least one of CAN bus, RS-485 differential signal, or Ethernet physical layer. The protocol layer defines the charging mode switching command code, status confirmation code, fault safety timeout mechanism, and charger address allocation rules.

8. The scene-driven fast switching control device according to claim 1, characterized in that, The digital control unit also includes a fail-safe unit, which is used to automatically maintain the current charging mode or switch to a preset safe charging mode when the scene switching signal is lost for more than a preset timeout period. The preset timeout period is from 10ms to 100ms.

9. A scene-driven fast switching control method for a battery charging system, applied to the scene-driven fast switching control device as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1: Receive external scene switching signal and determine whether the current scene state is the first charging mode or the second charging mode; S2: When the scenario state is the second charging mode, execute the fast constant voltage charging process: first, precharge the output side energy storage element through the output capacitor pre-charging unit; then start the charging mode switching control unit, and sequentially enter the current limiting soft start stage, the fast ramp stage and the steady state stage. Within the preset time threshold, switch the charging system from constant current charging mode to constant voltage charging mode, and enable the voltage smoothing mechanism of the voltage smoothing unit throughout the switching process to ensure that the voltage overshoot rate is less than the preset fluctuation threshold. S3: When the scenario state is the first charging mode, execute the fast constant current charging process: The charging mode switching control unit directly enters the fast ramp stage from the steady state stage, and switches the charging system from constant voltage charging mode to constant current charging mode within the preset time threshold. The voltage smoothing mechanism of the voltage smoothing unit is enabled throughout the switching process to ensure that the voltage overshoot rate is less than the preset fluctuation threshold. S4: During the execution of steps S2 and S3, the multi-machine synchronization unit receives an external synchronization trigger signal and locks the PWM switching frequency of each battery charging system to the same phase through a microsecond-level synchronization mechanism, thereby achieving multi-machine synchronous switching with a synchronization deviation less than a preset synchronization deviation threshold. S5: During the execution of steps S2 and S3, the charging mode switching control unit adopts a feedforward control method, directly calculates and outputs the target voltage trajectory based on the scene switching signal, and the generation of the target voltage trajectory does not depend on the real-time sampling feedback of the output voltage; during the steady-state operation phase, the charging mode switching control unit switches to a feedback control method, and performs closed-loop adjustment based on the real-time sampling value of the output voltage. S6: During the execution of steps S2 and S3, if the scene switching signal is lost for more than the preset timeout period, the fault safety unit automatically maintains the current charging mode or switches to the preset safe charging mode.

10. A battery charging system, characterized in that, Includes the scene-driven fast switching control device as described in any one of claims 1 to 8.

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