Self-adaptive overcurrent protection method and device for power device

Abstract

The invention relates to the technical field of overcurrent protection control, in particular to a self-adaptive overcurrent protection method and device for a power device, and the method comprises the steps: detecting the current working condition of a motor; based on the current working condition, calculating a grid resistance value and an over-current protection threshold which meet a preset optimal condition; and generating a configuration hardware parameter based on the gate resistance value and the overcurrent protection threshold, and generating an overcurrent protection action of the target power device based on the configured hardware parameter. Therefore, the problem that the protection margin of the system is insufficient under the high-risk working condition due to the fact that the existing overcurrent protection technology cannot meet the response speed requirement and cannot be adaptively adjusted according to the key state parameters in the related technology is solved.

Description

Adaptive overcurrent protection method and device for power devices Technical Field

[0001] This application relates to the field of overcurrent protection and control technology, and in particular to an adaptive overcurrent protection method and device for power devices. Background Technology

[0002] In power conversion devices such as motor controllers and inverters, overcurrent protection is a core function to ensure system safety.

[0003] Among related technologies, the current mainstream solutions include using an MCU to sample the current sensor signal through an ADC, performing software algorithm judgment, and outputting a shutdown signal via GPIO when the threshold is exceeded; or using a hardware comparator to handle rapid shutdown, while the MCU is responsible for fault latching, recording, and system recovery.

[0004] However, the operating state of the system (such as bus voltage and device junction temperature) is dynamic. Under high bus voltage or high temperature conditions, power devices are more vulnerable and require more sensitive protection. Existing software solutions have a slow response speed, and the protection thresholds of hardware solutions are all fixed values. They cannot be adaptively adjusted according to these key state parameters, resulting in insufficient protection margin of the system under certain high-risk operating conditions. Summary of the Invention This application provides an adaptive overcurrent protection method and device for power devices to solve the problems in the related art, such as the inability of existing overcurrent protection technology to meet the response speed requirements and the inability to adaptively adjust according to key state parameters, resulting in insufficient protection margin of the system under high-risk operating conditions.

[0005] The first aspect of this application provides an adaptive overcurrent protection method for a power device, comprising the following steps: detecting the current operating condition of a motor; calculating a gate resistance value and an overcurrent protection threshold that satisfy a preset optimal condition based on the current operating condition; generating configuration hardware parameters based on the gate resistance value and the overcurrent protection threshold, and generating an overcurrent protection action for a target power device based on the configured hardware parameters.

[0006] Through the aforementioned technical means, the embodiments of this application can dynamically calculate and configure the optimal gate resistance value and overcurrent protection threshold adapted to the current operating condition of the motor in real time, and generate hardware configuration parameters to drive the precise overcurrent protection action of the target power device. This not only breaks through the limitation of traditional fixed parameters not being able to match all operating conditions, but also achieves dynamic adaptation between operating conditions and hardware protection parameters. It can also significantly improve the accuracy and rapid response capability of overcurrent protection, while optimizing the switching losses, electromagnetic compatibility and operating efficiency of the motor system, effectively avoiding safety risks such as power device burnout, and improving maintainability through fault information recording. This comprehensively improves the operational safety, reliability and overall performance of the new energy vehicle motor system, adapting to the dynamic needs of complex driving scenarios.

[0007] Optionally, in one embodiment of this application, detecting the current operating condition of the motor includes: acquiring the bus voltage of the motor and obtaining the junction temperature of the target power device; and determining the actual junction temperature of the current operating condition based on the bus voltage and the junction temperature.

[0008] Through the above-mentioned technical means, the embodiments of this application can overcome the defects of single temperature detection being easily affected by voltage fluctuations by coordinating the correction of bus voltage and the junction temperature of the power device itself. It can accurately restore the true thermal state of the power device under different operating conditions, provide reliable data support for motor thermal management control and power device overload protection, effectively avoid device damage or performance redundancy caused by misjudgment of junction temperature, improve the stability and service life of motor operation, and adapt to the dynamic change requirements of operating conditions in complex voltage and load scenarios such as new energy vehicles.

[0009] Optionally, in one embodiment of this application, determining the actual junction temperature of the current operating condition based on the bus voltage and the junction temperature itself includes: obtaining the saturation voltage drop of the IGBT or the on-state voltage drop of the MOSFET, and obtaining the collector current; and determining the actual junction temperature of the current operating condition based on a preset relationship curve, according to the saturation voltage drop or on-state voltage drop, the collector current, and the junction temperature itself.

[0010] Through the above-mentioned technical means, the embodiments of this application can correct the interference of bus voltage fluctuations and load current changes on junction temperature detection by incorporating the coupling relationship between key electrical parameters such as device voltage drop and current and junction temperature, thereby significantly improving the detection accuracy of actual junction temperature. This provides more reliable core data support for motor thermal management control, power device overload protection, and dynamic optimization of control strategies, effectively avoiding device overheating damage or performance redundancy caused by misjudgment of junction temperature, and significantly improving the stability, reliability, and service life of motor operation. It is especially suitable for the dynamic changes in operating conditions under complex loads and wide voltage fluctuation scenarios such as new energy vehicles.

[0011] Optionally, in one embodiment of this application, the step of calculating the gate resistance value and overcurrent protection threshold that satisfy the preset optimal conditions based on the current operating conditions includes: determining the current stress index based on the current operating conditions; and calculating the gate resistance value and the overcurrent protection threshold based on the current stress index.

[0012] Optionally, in one embodiment of this application, generating the overcurrent protection action of the target power device based on the configured hardware parameters includes: determining whether an extreme fault has occurred based on the hardware parameters; if the extreme fault occurs, determining to trigger an interrupt, controlling the target power device to shut down, and recording the corresponding fault information.

[0013] Through the above-mentioned technical means, the embodiments of this application can overcome the limitations of traditional fixed parameter control. By dynamically linking the operating conditions, stress, and control parameters, the gate resistance value and the overcurrent protection threshold are precisely matched to the device stress state under the current operating conditions. This avoids problems such as excessive switching losses in high-frequency operating conditions and excessive EMI in low-frequency operating conditions caused by fixed parameters. Furthermore, the dynamic adjustment of the overcurrent protection threshold balances the protection sensitivity and the risk of false triggering, significantly improving the operational stability and service life of power devices. At the same time, it optimizes the energy efficiency and electromagnetic compatibility of the motor controller, adapting to the dynamic changes in all operating conditions of new energy vehicles, such as starting, acceleration, heavy load, and constant speed, providing core support for the improvement of vehicle safety and performance.

[0014] A second aspect of this application provides an adaptive overcurrent protection device for a power device, comprising: a detection module for detecting the current operating condition of a motor; a calculation module for calculating a gate resistance value and an overcurrent protection threshold that satisfy a preset optimal condition based on the current operating condition; and a protection module for generating configuration hardware parameters based on the gate resistance value and the overcurrent protection threshold, so as to generate an overcurrent protection action for a target power device based on the configured hardware parameters.

[0015] Through the aforementioned technical means, the embodiments of this application can dynamically calculate and configure the optimal gate resistance value and overcurrent protection threshold adapted to the current operating condition of the motor in real time, and generate hardware configuration parameters to drive the precise overcurrent protection action of the target power device. This not only breaks through the limitation of traditional fixed parameters not being able to match all operating conditions, but also achieves dynamic adaptation between operating conditions and hardware protection parameters. It can also significantly improve the accuracy and rapid response capability of overcurrent protection, while optimizing the switching losses, electromagnetic compatibility and operating efficiency of the motor system, effectively avoiding safety risks such as power device burnout, and improving maintainability through fault information recording. This comprehensively improves the operational safety, reliability and overall performance of the new energy vehicle motor system, adapting to the dynamic needs of complex driving scenarios.

[0016] Optionally, in one embodiment of this application, the detection module includes: a data acquisition unit for acquiring the bus voltage of the motor and obtaining the junction temperature of the target power device; and a first determination unit for determining the actual junction temperature of the current operating condition based on the bus voltage and the junction temperature.

[0017] Through the above-mentioned technical means, the embodiments of this application can overcome the defects of single temperature detection being easily affected by voltage fluctuations by coordinating the correction of bus voltage and the junction temperature of the power device itself. It can accurately restore the true thermal state of the power device under different operating conditions, provide reliable data support for motor thermal management control and power device overload protection, effectively avoid device damage or performance redundancy caused by misjudgment of junction temperature, improve the stability and service life of motor operation, and adapt to the dynamic change requirements of operating conditions in complex voltage and load scenarios such as new energy vehicles.

[0018] Optionally, in one embodiment of this application, the determining unit is used to: obtain the saturation voltage drop of the IGBT or the on-state voltage drop of the MOS transistor, and obtain the collector current; and determine the actual junction temperature of the current operating condition based on a preset relationship curve, according to the saturation voltage drop or on-state voltage drop, the collector current, and the junction temperature itself.

[0019] Through the above-mentioned technical means, the embodiments of this application can correct the interference of bus voltage fluctuations and load current changes on junction temperature detection by incorporating the coupling relationship between key electrical parameters such as device voltage drop and current and junction temperature, thereby significantly improving the detection accuracy of actual junction temperature. This provides more reliable core data support for motor thermal management control, power device overload protection, and dynamic optimization of control strategies, effectively avoiding device overheating damage or performance redundancy caused by misjudgment of junction temperature, and significantly improving the stability, reliability, and service life of motor operation. It is especially suitable for the dynamic changes in operating conditions under complex loads and wide voltage fluctuation scenarios such as new energy vehicles.

[0020] Optionally, in one embodiment of this application, the calculation module includes: a second determining unit, configured to determine a current stress index based on the current operating condition; and a calculation unit, configured to calculate the gate resistance value and the overcurrent protection threshold based on the current stress index.

[0021] Optionally, in one embodiment of this application, the protection module includes: a judgment unit, configured to determine whether an extreme fault has occurred based on the hardware parameters; and a control unit, configured to determine to trigger an interrupt if the extreme fault occurs, control the target power device to shut down, and record the corresponding fault information.

[0022] Through the above-mentioned technical means, the embodiments of this application can overcome the limitations of traditional fixed parameter control. By dynamically linking the operating conditions, stress, and control parameters, the gate resistance value and the overcurrent protection threshold are precisely matched to the device stress state under the current operating conditions. This avoids problems such as excessive switching losses in high-frequency operating conditions and excessive EMI in low-frequency operating conditions caused by fixed parameters. Furthermore, the dynamic adjustment of the overcurrent protection threshold balances the protection sensitivity and the risk of false triggering, significantly improving the operational stability and service life of power devices. At the same time, it optimizes the energy efficiency and electromagnetic compatibility of the motor controller, adapting to the dynamic changes in all operating conditions of new energy vehicles, such as starting, acceleration, heavy load, and constant speed, providing core support for the improvement of vehicle safety and performance.

[0023] A third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the adaptive overcurrent protection method for power devices as described in the above embodiments.

[0024] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the adaptive overcurrent protection method for power devices described above.

[0025] A fifth aspect of this application provides a computer program product that stores a computer program that, when executed by a processor, implements the adaptive overcurrent protection method for power devices as described above.

[0026] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0027] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: FIG1 is a flowchart of an adaptive overcurrent protection method for a power device according to an embodiment of this application; FIG2 is a schematic framework diagram of an adaptive overcurrent protection method according to a specific embodiment of this application; FIG3 is a flowchart of an adaptive software algorithm according to a specific embodiment of this application; FIG4 is a schematic structural diagram of an adaptive overcurrent protection device for a power device according to an embodiment of this application; FIG5 is a schematic structural diagram of an electronic device according to an embodiment of this application. Detailed Implementation

[0028] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0029] The adaptive overcurrent protection method and apparatus for power devices according to embodiments of this application are described below with reference to the accompanying drawings. Addressing the issues raised in the background section regarding existing overcurrent protection technologies that fail to meet response speed requirements and cannot adaptively adjust based on key state parameters, resulting in insufficient protection margin under high-risk operating conditions, this application provides an adaptive overcurrent protection method for power devices. In this method, the system operating condition is sensed, and the optimal gate resistance value and overcurrent protection threshold are simultaneously calculated based on the sensed operating condition. Furthermore, hardware parameters are dynamically configured, thereby executing overcurrent protection based on the configured parameters. This solves the problems in the related technologies where existing overcurrent protection technologies fail to meet response speed requirements and cannot adaptively adjust based on key state parameters, leading to insufficient protection margin under high-risk operating conditions.

[0030] Specifically, Figure 1 is a flowchart illustrating an adaptive overcurrent protection method for a power device provided in an embodiment of this application.

[0031] As shown in Figure 1, the adaptive overcurrent protection method of the power device includes the following steps: In step S101, the current operating condition of the motor is detected.

[0032] The current operating condition of the motor can be understood as the comprehensive working state of the motor during real-time operation, characterized by electrical parameters (such as bus voltage, stator current, and power output), mechanical parameters (such as speed, output torque, and load rate), thermal parameters (such as junction temperature of power devices and casing temperature), and operating modes (such as start-up, acceleration, constant speed, deceleration, regenerative braking, and overload). It intuitively reflects the motor's current load level, energy conversion efficiency, thermal management status, and operating mode. It is the core basis for motor control strategy optimization, fault warning, and thermal management regulation, and is adapted to the dynamic operating requirements of different application scenarios such as new energy vehicles and industrial equipment.

[0033] Optionally, in one embodiment of this application, detecting the current operating condition of the motor includes: acquiring the bus voltage of the motor and obtaining the junction temperature of the target power device; and determining the actual junction temperature of the current operating condition based on the bus voltage and the junction temperature.

[0034] This embodiment can accurately detect the core operating parameters of the motor by collecting the motor bus voltage and obtaining the junction temperature of the target power device itself, and by using the correlation characteristics of the two and algorithm calculations.

[0035] Taking SiC power devices in new energy vehicle drive motors as an example: During vehicle operation, the motor controller (MCU) collects the bus voltage (e.g., 250V-420V) in real time through a voltage sampling circuit, and obtains the junction temperature (e.g., 50℃-130℃) of the SiC device through its built-in temperature sensing unit. Combining the voltage-junction temperature characteristic curve of the SiC device pre-stored in the MCU (this curve has been calibrated through previous experiments to clarify the correlation between the device's conduction loss and junction temperature under different bus voltages), the algorithm corrects the junction temperature deviation caused by voltage fluctuations (e.g., when the bus voltage increases, the change in the SiC device's on-state voltage drop causes a deviation of 8℃-12℃ between its own junction temperature and the actual operating temperature), and finally calculates the actual junction temperature of the SiC device under the current operating conditions. When the actual junction temperature reaches 145℃ (90% of the safety threshold), the MCU automatically adjusts the PWM output strategy to reduce the motor's output power, ensuring that the SiC device operates within a safe temperature range and guaranteeing the continuous and stable operation of the motor.

[0036] Through the above-mentioned technical means, the embodiments of this application can overcome the defects of single temperature detection being easily affected by voltage fluctuations by coordinating the correction of bus voltage and the junction temperature of the power device itself. It can accurately restore the true thermal state of the power device under different operating conditions, provide reliable data support for motor thermal management control and power device overload protection, effectively avoid device damage or performance redundancy caused by misjudgment of junction temperature, improve the stability and service life of motor operation, and adapt to the dynamic change requirements of operating conditions in complex voltage and load scenarios such as new energy vehicles.

[0037] Optionally, in one embodiment of this application, determining the actual junction temperature under the current operating condition based on the bus voltage and the junction temperature itself includes: obtaining the saturation voltage drop of the IGBT or the on-state voltage drop of the MOSFET, and obtaining the collector current; and determining the actual junction temperature under the current operating condition based on a preset relationship curve, according to the saturation voltage drop or on-state voltage drop, the collector current, and the junction temperature itself.

[0038] Specifically, embodiments of this application can directly obtain the junction temperature of the power device itself, based on the saturation voltage drop V of the IGBT. ce Or the on-state voltage drop V of the MOSFET ds With junction temperature T j and collector current I c The strong, predictable functional relationship can be identified by applying a very small measurement current (e.g., 1% of the rated current) during the tiny dead time of the chip switching action, while simultaneously sampling V at this moment with a high-precision ADC. ce Voltage, based on pre-calibrated V ce -I c -T j The curve (usually available in the chip datasheet) can be used to accurately deduce the current junction temperature T. j .

[0039] Through the above-mentioned technical means, the embodiments of this application can correct the interference of bus voltage fluctuations and load current changes on junction temperature detection by incorporating the coupling relationship between key electrical parameters such as device voltage drop and current and junction temperature, thereby significantly improving the detection accuracy of actual junction temperature. This provides more reliable core data support for motor thermal management control, power device overload protection, and dynamic optimization of control strategies, effectively avoiding device overheating damage or performance redundancy caused by misjudgment of junction temperature, and significantly improving the stability, reliability, and service life of motor operation. It is especially suitable for the dynamic changes in operating conditions under complex loads and wide voltage fluctuation scenarios such as new energy vehicles.

[0040] In step S102, based on the current operating conditions, the gate resistance value and overcurrent protection threshold that satisfy the preset optimal conditions are calculated.

[0041] The gate resistor is a resistor element connected in series between the gate of a power device (IGBT / MOS transistor) and the drive circuit. Its resistance value is a key parameter for the switching characteristics of the control device, and the common range is 1Ω-100Ω (5Ω-20Ω is mostly used in motor controllers of new energy vehicles).

[0042] The overcurrent protection threshold is a current protection critical value set by the motor controller (MCU) or power device driver chip. When the collector current or drain current of the power device is detected to exceed the threshold, the system immediately triggers the protection action to prevent the device from burning out due to overcurrent.

[0043] Optionally, in one embodiment of this application, calculating the gate resistance value and overcurrent protection threshold that satisfy the preset optimal conditions based on the current operating conditions includes: determining the current stress index based on the current operating conditions; and calculating the gate resistance value and overcurrent protection threshold based on the current stress index.

[0044] This application embodiment can dynamically adapt power devices (IGBT / MOS transistors) to different operating conditions of motors. First, it determines the current stress index (including current stress, voltage stress, and thermal stress) of the device by using current operating parameters (such as bus voltage, actual junction temperature, collector current, speed, and torque). Then, based on a preset "stress index - gate resistance value - overcurrent protection threshold" optimization matching model, it dynamically calculates and outputs the gate resistance value and overcurrent protection threshold that meet the optimal conditions (such as minimum switching loss, EMC compliance, and sufficient device safety redundancy), thereby achieving real-time adaptation between operating conditions and device control parameters.

[0045] As one possible approach, embodiments of this application can apply an adaptive control algorithm (such as PID, state machine, or simple lookup table method) in the MCU, first periodically reading the bus voltage V. bus and the estimated precise junction temperature T j Furthermore, a gate resistor or gate resistor, controllable by the MCU, is applied on the driver board, with a resistance value of R. g Based on preset optimization objectives (such as maximum efficiency and minimum stress), the algorithm calculates in real time the optimal resistance value R to be used in the next cycle. g and protection threshold Vr ef_slope Furthermore, external circuitry can be configured via digital interfaces (SPI / I2C), which makes the protection parameters no longer fixed but dynamically optimal.

[0046] Through the above-mentioned technical means, the embodiments of this application can overcome the limitations of traditional fixed parameter control. By dynamically linking the operating conditions, stress, and control parameters, the gate resistance value and the overcurrent protection threshold are precisely matched to the device stress state under the current operating conditions. This avoids problems such as excessive switching losses in high-frequency operating conditions and excessive EMI in low-frequency operating conditions caused by fixed parameters. Furthermore, the dynamic adjustment of the overcurrent protection threshold balances the protection sensitivity and the risk of false triggering, significantly improving the operational stability and service life of power devices. At the same time, it optimizes the energy efficiency and electromagnetic compatibility of the motor controller, adapting to the dynamic changes in all operating conditions of new energy vehicles, such as starting, acceleration, heavy load, and constant speed, providing core support for the improvement of vehicle safety and performance.

[0047] In step S103, configuration hardware parameters are generated based on the gate resistance value and the overcurrent protection threshold, so as to generate the overcurrent protection action of the target power device based on the configured hardware parameters.

[0048] Optionally, in one embodiment of this application, generating the overcurrent protection action of the target power device based on the configured hardware parameters includes: determining whether an extreme fault has occurred based on the hardware parameters; if an extreme fault has occurred, determining to trigger an interrupt, controlling the target power device to shut down, and recording the corresponding fault information.

[0049] Specifically, this application embodiment can set a hardware overcurrent protection channel, as shown in Figure 2. This channel can be a pure, software-free analog-to-digital mixed circuit, consisting of a current sensor, a differentiating circuit, a comparator, a latch, and a logic gate digital-to-analog converter. First, the current sensor collects the current, and the current signal is input into the differentiating circuit to obtain the differentiated signal. Once the differentiated signal exceeds the threshold set by the DAC, the comparator flips, the latch instantly latches this fault state, and the logic gate immediately shuts down the driver chip, thereby turning off the power device. The MCU's fault signal serves as a second layer of protection and can be logically ANDed with the hardware signal.

[0050] In this case, since the short-circuit fault current may be a spike, without a latch, the comparator output may reset immediately after the fault disappears, resulting in a too narrow shutdown pulse. The driver chip may not be able to recognize or completely shut down the device. However, the latch can latch the fault state to ensure that the shutdown signal remains valid until the MCU intervenes and resets it.

[0051] This channel can perform logical operations on hardware fault signals and other fault signals that the MCU may emit (such as overvoltage or overheating). For example, all fault signals (active low) can be connected to an AND gate; as long as one of them goes low, the output goes low, triggering shutdown.

[0052] The digital-to-analog converter receives digital commands sent by the MCU via SPI and converts them into analog voltage V. ref_slope, which serves as a variable reference for the comparator.

[0053] Through the aforementioned technical means, the embodiments of this application can overcome the limitations of traditional fixed hardware parameters that cannot be matched with all operating conditions by dynamically adapting hardware parameters to operating conditions and by using a fault interruption mechanism. This ensures both the accuracy and speed of overcurrent protection actions and avoids false triggering or response delays caused by parameter mismatch. At the same time, fault information recording can provide a basis for later troubleshooting, significantly improving the operational safety and reliability of power devices and motor controllers, effectively avoiding device burnout and vehicle safety risks caused by extreme faults, and adapting to the dynamic protection needs of new energy vehicles in complex driving scenarios.

[0054] Furthermore, the software flow of the adaptive algorithm is shown in Figure 3, which may include: initialization and startup: after the system is powered on, all the peripherals that need to be used are configured, and then the system waits for the start command of the vehicle controller (VCU), and then enables PWM and the motor starts running.

[0055] Main loop (adaptive control core): 1. Read operating conditions: In each control cycle (e.g., 1ms), the MCU reads the bus voltage V from the ADC. bus_adc Junction temperature estimate T from the driver chip j_est and load current I out .

[0056] 2. Calculate the stress: V bus and T j These two core parameters combine to form a comprehensive stress index (SI), for example, SI = k1*V bus + k2*T j .

[0057] 3. Algorithm Decision: Adaptive algorithms (such as PID controllers or lookup table methods) calculate the optimal target gate resistance value R based on the current SI value. g_target and the target value of the protection slope threshold V ref_slope .

[0058] 4. Execution Output: The MCU sends the calculated digital instructions to the digital potentiometer (controller R) via the SPI interface. g ) and DAC (controller V) ref_slope This allows for the dynamic configuration of hardware parameters.

[0059] 5. Loop Waiting: After completing one configuration, wait for the next control cycle to arrive and start a new round of perception-decision-execution loop.

[0060] 6. Interrupt Handling (Safety Assurance): This is a high-priority independent process. When the hardware comparator detects an extreme fault and triggers an interrupt, the MCU immediately executes the top-level safety shutdown and fault logging. This process is completely independent of the main loop, ensuring the highest reliability.

[0061] Table 1 provides a visual example of how the system adaptively adjusts parameters under different typical driving conditions. The values ​​in the table are illustrative; actual values ​​need to be calibrated based on specific motor calibration test results, IGBT modules, and system design.

[0062] Table 1

[0063] Cold start: In low-temperature environments, the chip has a high on-resistance but strong withstand voltage, allowing the system to tolerate lower R values. g (Improved cooling efficiency) and higher V ref_slope (To avoid false alarms from switch noise at low temperatures).

[0064] Rapid acceleration / full throttle (High load): At this time, the motor demands extremely high torque, the bus current surges, and the IGBT junction temperature T... j When the price rises rapidly, the system should automatically increase R. g (Slowing down switching reduces losses and avoids overheating), while also reducing V ref_slope (Improves protection sensitivity and prevents overcurrent damage), corresponding to the "high pressure / high temperature → more protection" strategy.

[0065] High-speed cruising (medium load): The vehicle is running stably and the system is in its efficient range. At this time, the R value can be appropriately reduced. g (Increase switching speed to reduce conduction losses and optimize energy efficiency), while moderately increasing V ref_slope (To prevent false triggering by normal switching noise), corresponding to the "low voltage and low temperature → better performance" strategy.

[0066] Regenerative braking (energy recovery): The motor operates as a generator, and the bus voltage V bus The voltage rises significantly due to energy recharging (potentially exceeding the rated value). Although the junction temperature is not high at this point, the high voltage means that the switching transistor needs to withstand higher stress. The system should prioritize reducing the voltage. ref_slope (Prevent overvoltage from causing device breakdown), and simultaneously fine-tune R. g Balance EMI to highlight V bus The response.

[0067] Hot Soak: When a vehicle is started immediately after being stationary, the radiator temperature is high but the chip is not hot. The system needs to adjust according to the initial T... j Anticipating the thermal state, a conservative initial setting (slightly higher R) is adopted. g Slightly lower V ref_slope(This can be adjusted according to actual operation.)

[0068] In a specific embodiment, a permanent magnet synchronous motor and its inverter of a certain new energy vehicle can be selected as the controlled object. Specifically, the following settings can be made: Core processor: main control MCU, with a built-in powerful ADC module and multiple SPI interfaces.

[0069] Junction temperature sensing: using V ce(sat) Measurement method. During the PWM dead time, the high-side gate driver chip injects a small measurement current into the IGBT, and its built-in ADC samples V. ce The voltage is sent to the main MCU via SPI for junction temperature estimation.

[0070] Dynamic actuator: R g Control: A digital potentiometer is controlled by the MCU via SPI, and its output determines the gate resistor value selected by the analog switch array (e.g., 2.2Ω, 3.3Ω, 4.7Ω, 6.8Ω).

[0071] V ref_slope Control: A DAC (MCP4921) is controlled by the MCU via SPI, and its output voltage (0.5V - 3.0V) serves as the reference voltage V for a hardware comparator (such as LMV331). ref_slope In summary, the key technologies of the overcurrent protection method provided in this application embodiment can be summarized as follows: 1. The current bus voltage and power device junction temperature of the system are collected to determine the operating condition. Then, through the adaptive algorithm in the MCU, the overcurrent protection threshold and gate resistor value are flexibly set. The threshold is input into the hardware circuit comparator. The two paths are integrated through logic gates, with hardware as the main driver and software as the auxiliary driver. This ensures the fastest protection speed and enables intelligent decision-making, thus resolving the contradiction between speed and intelligence.

[0072] 2. The dynamic overcurrent protection threshold setting is continuous, and combined with the hardware circuit, it systematically realizes fast-response overcurrent protection. The protection parameters are dynamically adjusted variables according to real-time operating conditions, which can realize real-time matching between protection strategy and system status.

[0073] The adaptive overcurrent protection method for power devices proposed in this application can sense the system operating conditions, synchronously calculate the optimal gate resistance value and overcurrent protection threshold based on the sensed operating conditions, and further dynamically configure hardware parameters to execute overcurrent protection based on the configured parameters. This solves the problems in related technologies, such as existing overcurrent protection technologies failing to meet response speed requirements and failing to adaptively adjust according to key state parameters, resulting in insufficient protection margin under high-risk operating conditions.

[0074] Next, referring to Figure 4, an adaptive overcurrent protection device for power devices according to an embodiment of this application is described.

[0075] Figure 4 is a block diagram of an adaptive overcurrent protection device for a power device according to an embodiment of this application.

[0076] As shown in Figure 4, the adaptive overcurrent protection device 10 of the power device includes: a detection module 100, a calculation module 200, and a protection module 300.

[0077] The detection module 100 is used to detect the current operating condition of the motor.

[0078] The calculation module 200 is used to calculate the gate resistance value and overcurrent protection threshold that meet the preset optimal conditions based on the current operating conditions.

[0079] The protection module 300 is used to generate configuration hardware parameters based on the gate resistance value and the overcurrent protection threshold, so as to generate the overcurrent protection action of the target power device based on the configured hardware parameters.

[0080] Optionally, in one embodiment of this application, the detection module 100 includes: a data acquisition unit and a first determination unit; wherein, the data acquisition unit is used to acquire the bus voltage of the motor and obtain the junction temperature of the target power device; the first determination unit is used to determine the actual junction temperature under the current operating condition based on the bus voltage and the junction temperature.

[0081] Optionally, in one embodiment of this application, the determining unit is used to: obtain the saturation voltage drop of the IGBT or the on-state voltage drop of the MOSFET, and obtain the collector current; and determine the actual junction temperature under the current operating condition based on a preset relationship curve, according to the saturation voltage drop or on-state voltage drop, the collector current, and the junction temperature itself.

[0082] Optionally, in one embodiment of this application, the calculation module 200 includes: a second determining unit and a calculation unit; wherein, the second determining unit is used to determine the current stress index based on the current operating conditions; and the calculation unit is used to calculate the gate resistance value and the overcurrent protection threshold according to the current stress index.

[0083] Optionally, in one embodiment of this application, the protection module 300 includes: a judgment unit and a control unit; wherein, the judgment unit is used to determine whether an extreme fault has occurred based on hardware parameters; the control unit is used to determine whether an interrupt is triggered, control the target power device to turn off, and record the corresponding fault information if an extreme fault occurs.

[0084] The aforementioned adaptive overcurrent protection device can utilize the powerful computing capabilities of the MCU to execute adaptive algorithms in real time, accurately calculate the optimal protection parameters based on the current operating conditions of the motor, and improve the safety of the system under different operating conditions. In addition, it can also estimate the junction temperature of power devices in real time through software algorithms, providing high-precision key state inputs for the adaptive algorithm.

[0085] It should be noted that the explanation of the aforementioned embodiment of the adaptive overcurrent protection method for power devices also applies to the adaptive overcurrent protection device for power devices in this embodiment, and will not be repeated here.

[0086] The adaptive overcurrent protection device for power devices proposed in this application can sense the system operating conditions, synchronously calculate the optimal gate resistance value and overcurrent protection threshold based on the sensed operating conditions, and further dynamically configure hardware parameters, thereby executing overcurrent protection based on the configured parameters. This solves the problems in related technologies, such as existing overcurrent protection technologies failing to meet response speed requirements and failing to adaptively adjust according to key state parameters, resulting in insufficient protection margin under high-risk operating conditions.

[0087] Figure 5 is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include: a memory 501, a processor 502, and a computer program stored in the memory 501 and executable on the processor 502.

[0088] When the processor 502 executes the program, it implements the adaptive overcurrent protection method for power devices provided in the above embodiments.

[0089] Furthermore, the electronic device also includes a communication interface 503 for communication between the memory 501 and the processor 502.

[0090] The memory 501 is used to store computer programs that can run on the processor 502.

[0091] Memory 501 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0092] If the memory 501, processor 502, and communication interface 503 are implemented independently, they can be interconnected via a bus to communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, only one thick line is used in Figure 5, but this does not indicate that there is only one bus or one type of bus.

[0093] Optionally, in a specific implementation, if the memory 501, processor 502, and communication interface 503 are integrated on a single chip, then the memory 501, processor 502, and communication interface 503 can communicate with each other through an internal interface.

[0094] Processor 502 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0095] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described adaptive overcurrent protection method for power devices.

[0096] This application also provides a computer program product storing a computer program that, when executed by a processor, implements the above-described adaptive overcurrent protection method for power devices.

[0097] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0098] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0099] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0100] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0101] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, it can be implemented using any one or more of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0102] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0103] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0104] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. An adaptive overcurrent protection method for power devices, characterized in that, Includes the following steps: Detect the current operating condition of the motor; Based on the current operating conditions, calculate the gate resistance value and overcurrent protection threshold that satisfy the preset optimal conditions; Based on the gate resistance value and overcurrent protection threshold, configuration hardware parameters are generated to generate the overcurrent protection action of the target power device based on the configured hardware parameters.

2. The method according to claim 1, characterized in that, The detection of the current operating condition of the motor includes: acquiring the bus voltage of the motor and obtaining the junction temperature of the target power device; and determining the actual junction temperature of the current operating condition based on the bus voltage and the junction temperature.

3. The method according to claim 2, characterized in that, The step of determining the actual junction temperature of the current operating condition based on the bus voltage and the junction temperature itself includes: obtaining the saturation voltage drop of the IGBT or the on-state voltage drop of the MOSFET, and obtaining the collector current; and determining the actual junction temperature of the current operating condition based on a preset relationship curve, according to the saturation voltage drop or on-state voltage drop, the collector current, and the junction temperature itself.

4. The method according to claim 1, characterized in that, The step of calculating the gate resistance value and overcurrent protection threshold that satisfy the preset optimal conditions based on the current operating conditions includes: determining the current stress index based on the current operating conditions; and calculating the gate resistance value and the overcurrent protection threshold based on the current stress index.

5. The method according to claim 1, characterized in that, The process of generating overcurrent protection actions for the target power device based on the configured hardware parameters includes: determining whether an extreme fault has occurred based on the hardware parameters; if the extreme fault occurs, determining to trigger an interrupt, controlling the target power device to shut down, and recording the corresponding fault information.

6. An adaptive overcurrent protection device for a power device, characterized in that, include: The detection module is used to detect the current operating condition of the motor; The calculation module is used to calculate the gate resistance value and overcurrent protection threshold that meet the preset optimal conditions based on the current operating conditions. The protection module is used to generate configuration hardware parameters based on the gate resistance value and the overcurrent protection threshold, so as to generate the overcurrent protection action of the target power device based on the configured hardware parameters.

7. The apparatus according to claim 6, characterized in that, The detection module includes: a data acquisition unit for acquiring the bus voltage of the motor and obtaining the junction temperature of the target power device; and a first determination unit for determining the actual junction temperature of the current operating condition based on the bus voltage and the junction temperature.

8. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the adaptive overcurrent protection method for the power device as described in any one of claims 1-5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the adaptive overcurrent protection method for the power device as described in any one of claims 1-5.

10. A computer program product, comprising a computer program, characterized in that, The computer program is executed to implement the adaptive overcurrent protection method for the power device as described in any one of claims 1-5.

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