Electric vehicle integrated thermal management electronic fan rotating speed control system and method

Abstract

The invention discloses an integrated thermal management electronic fan rotating speed control system for an electric vehicle. The system comprises a sensor module, a controller and a fan driving module. The sensor module collects temperature information of an electric drive system, temperature information of a power battery system and pressure information of an air-conditioning system. After receiving the information, the controller determines the required rotating speed corresponding to each system, obtains a final target rotating speed through overall planning and processing, and generates a control signal; the fan driving module drives the electronic fan to operate according to the control signal. According to the invention, integrated heat management of three core heat dissipation sources is realized, and the cost and the layout space are optimized; a fan protection mechanism is introduced to prolong the service life of components; an advanced control strategy is adopted to simplify calibration, and the driving comfort is improved.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle electronic fan speed control technology, specifically to an integrated thermal management electronic fan speed control system and method for electric vehicles. Background Technology

[0002] With the development of pure electric vehicle technology, the integration and efficiency of the vehicle's thermal management system are becoming increasingly important. The electric drive system, power battery system, and air conditioning system are the three main heat sources in pure electric vehicles. Existing technologies have proposed preliminary integration of the electric drive system and air conditioning system by sharing an electric fan to optimize heat dissipation resources.

[0003] Specifically, a typical existing technical solution is as follows: First, the required fan speed of the electric drive system is determined based on the temperature information of the electric drive system (including motor temperature, motor controller temperature, etc.); simultaneously, the required fan speed of the air conditioning system is determined based on the status information of the air conditioning system (such as refrigeration pipe pressure, compressor speed). Then, the larger of the two required speeds is taken as the reference speed, and this reference speed is further corrected using parameters such as vehicle speed and ambient temperature, ultimately achieving stepless speed regulation of the condenser fan.

[0004] However, this existing technical solution has the following obvious drawbacks: 1. Insufficient integration, failing to cover core heat dissipation units: Current technology only integrates the electric drive system and air conditioning system, but does not include the power battery system, a key heat source, within the integrated thermal management scope. This means that in practical applications, a separate cooling fan is still required for the power battery system. For new energy vehicles with compact layouts and strict cost control, this not only increases additional component costs and occupies valuable layout space, but also fragments the thermal management strategy, preventing the achievement of global optimization.

[0005] 2. Lack of protection mechanism for the fan body, affecting its service life: When controlling the start and stop of the fan, the existing technology adopts a simple strategy of "starting when needed and stopping when not needed," without any protection logic. When the vehicle's operating conditions change frequently, this direct start and stop can easily lead to frequent start and stop of the electric fan, thereby impacting its motor and drive mechanism and severely shortening the fan's service life.

[0006] 3. Control strategies rely heavily on calibration, resulting in poor adaptability and accuracy: When controlling air conditioning systems, existing technologies require tedious mapping calibration of parameters such as fan speed and compressor speed. To ensure control accuracy, the calibration workload is enormous. Furthermore, this calibration relationship is closely dependent on a specific compressor model; if the compressor model is changed, the entire calibration process must be repeated, lacking universality and flexibility, and resulting in high maintenance costs.

[0007] Therefore, there is an urgent need in this field for a more integrated electric vehicle thermal management fan speed control solution that can effectively protect the fan and has a better control strategy. Summary of the Invention

[0008] In view of the shortcomings in the prior art, the present invention provides an integrated thermal management electronic fan speed control system for electric vehicles.

[0009] The technical solution adopted in this invention is: an integrated thermal management electronic fan speed control system for electric vehicles, comprising: The sensor module is used to collect temperature information from the electric drive system, the power battery system, and the air conditioning system. The controller, which is signal-connected to the sensor module, is configured as follows: Receive information collected by the sensor module; The first required speed is determined based on the temperature information of the electric drive system, the second required speed is determined based on the temperature information of the power battery system, and the third required speed is determined based on the pressure information of the air conditioning system. The first required speed, the second required speed, and the third required speed are processed in a coordinated manner to determine the final target speed; And generate a control signal corresponding to the final target rotational speed; And a fan drive module, which is connected to the controller and the electronic fan signal, for driving the electronic fan to run at the final target speed according to the control signal.

[0010] Furthermore, the controller comprehensively processes the first required speed, the second required speed, and the third required speed, specifically including: The maximum value among the first required speed, the second required speed, and the third required speed is determined as the final target speed.

[0011] Furthermore, the controller is also configured to perform delayed shutdown control: When the final target speed changes from a non-zero value to zero, the fan drive module is controlled to drive the electronic fan to continue running at the preset minimum speed for a predetermined delay time, and then the electronic fan is controlled to stop.

[0012] Furthermore, the controller is also configured to perform protection against frequent start-stop cycles: Monitor the number of times the electronic fan starts and stops within a preset time window; If the number of start-stop cycles exceeds a preset threshold, the electronic fan will be controlled to maintain an operating speed of no less than the preset speed during the subsequent protection period, without responding to the command that the final target speed becomes zero.

[0013] Furthermore, the controller employs a PID control algorithm to precisely control the actual speed of the electronic fan to the final target speed by adjusting the PID parameters.

[0014] This application also improves a method for controlling the speed of an integrated thermal management electronic fan in an electric vehicle according to the aforementioned system, comprising the following steps: S1. Data Acquisition Steps: Real-time acquisition of temperature information from the electric drive system, the power battery system, and the air conditioning system via sensor modules; S2. Demand Calculation Steps: Calculate the first required speed based on the temperature information of the electric drive system, calculate the second required speed based on the temperature information of the power battery system, and calculate the third required speed based on the pressure information of the air conditioning system. S3. Overall decision-making step: The first required speed, the second required speed and the third required speed are processed in a coordinated manner to generate the final target speed; S4. Control execution steps: Based on the final target speed, control the operation of the electronic fan through the fan drive module.

[0015] Furthermore, the overall decision-making steps include: Compare the first required speed, the second required speed, and the third required speed; The maximum value among the three is set as the final target rotational speed.

[0016] Furthermore, the control execution steps also include a delayed shutdown step: When it is determined that the final target speed needs to change from a non-zero value to zero, the electronic fan is controlled to continue running at the preset minimum speed for a predetermined delay time before the shutdown operation is performed.

[0017] Furthermore, the control execution steps also include a protection step against frequent start-stop cycles: The number of start-stop cycles of the electronic fan within a preset time window is counted. If the number of times exceeds the preset safety threshold, the shutdown command is ignored, and the electronic fan is controlled to continue running at a speed not lower than the preset protection speed for the next protection time.

[0018] Furthermore, in the control execution step, a PID control algorithm is used to adjust the actual speed of the electric fan to stably track the final target speed through feedback.

[0019] The beneficial effects of this invention are: 1. It achieves high-level integrated thermal management, optimizing system cost and layout space.

[0020] This invention comprehensively considers the heat dissipation needs of the three core heat sources—the electric drive system, the power battery system, and the air conditioning system—and simultaneously meets the heat dissipation requirements of all systems through an integrated control logic and a single electric fan. This completely changes the existing technology's fan configuration scheme that requires independent cooling for the power battery system. It saves valuable space in the engine compartment, providing greater flexibility for the overall vehicle structural design. Furthermore, through integrated management, the system can precisely allocate fan speeds based on the vehicle's real-time, comprehensive thermal load, avoiding the resource waste that might result from controlling a single system individually, thereby further reducing the vehicle's overall energy consumption.

[0021] 2. An intelligent fan protection mechanism has been introduced, which effectively extends the service life of core components and improves system reliability.

[0022] This invention introduces delayed shutdown and anti-frequent start-stop protection logic into the start-stop process of the electric fan, resulting in multiple beneficial effects. Specifically, the delayed shutdown function (such as controlling the fan to continue running for a period of time after the compressor stops) effectively dissipates residual heat in the system, preventing excessively high instantaneous pressure in the air conditioning system pipes caused by the fan stopping immediately, thus protecting the air conditioning system components. Simultaneously, the anti-frequent start-stop function significantly reduces damage to the fan motor and transmission mechanism caused by frequent inrush currents and mechanical stress by suppressing repeated starts within a short period. These two protection mechanisms work together to greatly extend the service life of the electric fan and improve the long-term operational reliability of the vehicle's thermal management system.

[0023] 3. It adopts an advanced and robust control strategy, which simplifies the calibration process and improves control quality and ride comfort.

[0024] Because the core control algorithm of this invention uses PID (Proportional-Integral-Derivative) control to adjust the fan speed, its advantages are particularly prominent compared to existing control methods that rely on a large number of preset mapping relationships. PID control is a closed-loop control based on real-time feedback, which greatly reduces the workload of tedious calibration of parameters such as different compressor speeds, making the control system more versatile and adaptable, and reducing development and maintenance costs. At the same time, PID control can achieve smooth and continuous adjustment of fan speed, effectively avoiding speed jumps or abrupt changes that may occur in traditional methods. This smooth speed change avoids sudden increases or decreases in fan noise, significantly improving in-vehicle NVH (noise, vibration, and harshness) performance and enhancing the comfort of passengers.

[0025] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0026] Figure 1 A block diagram of the structure of an integrated thermal management electronic fan speed control system for electric vehicles.

[0027] Figure 2 A schematic diagram of a method for controlling the speed of an electronic fan integrated with thermal management in an electric vehicle. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0030] This invention provides an integrated thermal management electronic fan speed control system for electric vehicles.

[0031] In this embodiment, refer to Figure 1-2 The electric vehicle integrates a thermal management electronic fan speed control system, including: The sensor module is used to collect temperature information from the electric drive system, the power battery system, and the air conditioning system. The controller, which is signal-connected to the sensor module, is configured as follows: Receive information collected by the sensor module; The first required speed is determined based on the temperature information of the electric drive system, the second required speed is determined based on the temperature information of the power battery system, and the third required speed is determined based on the pressure information of the air conditioning system. The first required speed, the second required speed, and the third required speed are processed in a coordinated manner to determine the final target speed; And generate a control signal corresponding to the final target rotational speed; And a fan drive module, which is connected to the controller and the electronic fan signal, for driving the electronic fan to run at the final target speed according to the control signal.

[0032] In the above technical solution, a sensor module comprehensively senses the key status parameters (temperature, pressure) of the three major heat sources of the electric vehicle (electric drive system, power battery system, and air conditioning system). This information is transmitted to a central controller, which calculates the fan speed required for each system to operate independently. The controller does not directly adopt any single required speed, but instead uses a comprehensive processing algorithm to integrate the three required speeds and determine a final target speed that simultaneously meets the heat dissipation needs of all systems. Finally, the fan drive module executes this speed command to drive the electric fan.

[0033] This represents a paradigm shift from "independent control of subsystems" to "integrated control of vehicle thermal management." It fundamentally solves the problems of high cost and limited layout space caused by the lack of integration of the power battery system in existing technologies, laying the foundation for energy consumption optimization at the vehicle level.

[0034] For example, in hot summer weather, a vehicle is undergoing DC fast charging, generating significant heat in the battery system. Simultaneously, the driver turns on the air conditioning. The system then activates: the sensor module detects that the battery pack temperature has risen to 35°C, the air conditioning high-pressure line pressure has risen to 1.8 MPa, and the electric drive system, being inactive, has a moderate temperature (40°C). Based on this, the controller calculates the second required speed (battery system, corresponding to 35°C) as 1500 rpm, the third required speed (air conditioning system, corresponding to 1.8 MPa) as 1800 rpm, and the first required speed (electric drive system) as 0 rpm. After comprehensive processing (e.g., taking the maximum value), the final target speed is set at 1800 rpm. The fan drive module then drives the electric fan to operate at 1800 rpm, providing sufficient cooling airflow for both the battery and the air conditioning condenser.

[0035] Specifically, the controller comprehensively processes the first required speed, the second required speed, and the third required speed, including: The maximum value among the first required speed, the second required speed, and the third required speed is determined as the final target speed.

[0036] The principle behind this technical solution is to employ a strategy that maximizes demand satisfaction. Specifically, it compares the required engine speeds calculated by the three systems and selects the one with the largest value as the final target speed. This strategy ensures that the system with the highest heat dissipation demand is always satisfied under any operating condition, thus guaranteeing the thermal safety of the entire vehicle. Furthermore, the algorithm is simple in logic, highly efficient in computation, and has a rapid response time. It also requires no complex calibration and exhibits strong robustness.

[0037] Continuing with the previous example, the controller calculates three required speeds: 0 rpm (electric drive), 1500 rpm (battery), and 1800 rpm (air conditioning). According to the strategy in this claim, the controller directly sets the maximum value of 1800 rpm as the final target speed, ensuring the heat dissipation performance of the air conditioning system while also fully covering the battery system's 1500 rpm heat dissipation requirement.

[0038] Specifically, the controller is also configured to perform delayed shutdown control: When the final target speed changes from a non-zero value to zero, the fan drive module is controlled to drive the electronic fan to continue running at the preset minimum speed for a predetermined delay time, and then the electronic fan is controlled to stop.

[0039] This solution incorporates a delayed shutdown control. The principle is that when the controller determines that the cooling demand has disappeared (the final target speed needs to be reduced to 0), it does not immediately cut off the fan power. Instead, it controls the fan to continue running at a preset minimum speed for a preset delay time, using the residual airflow to carry away the remaining heat from the system before smoothly shutting down.

[0040] This effectively prevents a sudden spike in air conditioning system pipe pressure caused by a sudden fan stop (especially when the compressor stops), protecting components such as the air conditioning compressor. At the same time, the smooth shutdown process also reduces current and mechanical shocks to the fan motor.

[0041] For example, after fast charging ends and the driver turns off the air conditioning, the cooling demand of the battery and air conditioning decreases rapidly, eventually requiring the engine speed to drop from 1800 rpm to 0 rpm. At this point, the controller does not immediately stop the fan, but instead keeps it running at a minimum speed of 800 rpm for 30 seconds. During these 30 seconds, the residual airflow dissipates the remaining heat on the condenser and battery pack surface, causing the system pressure to drop steadily. Only after 30 seconds does the fan completely stop working.

[0042] Specifically, the controller is also configured to perform protection against frequent start-stop cycles: Monitor the number of times the electronic fan starts and stops within a preset time window; If the number of start-stop cycles exceeds a preset threshold, the electronic fan will be controlled to maintain an operating speed of no less than the preset speed during the subsequent protection period, without responding to the command that the final target speed becomes zero.

[0043] This solution incorporates a protection logic to prevent frequent start-stop operations. The principle is that the controller has an internal timer and counter to monitor the number of fan start-stop cycles within a specific time window. When the number exceeds a preset safety threshold, the controller determines it as "frequent start-stop" and triggers the protection logic: during the subsequent protection period, the fan is forced to maintain an operating speed no lower than a certain preset speed, ignoring shutdown commands indicating reduced cooling demand.

[0044] This greatly avoids the cumulative damage to the motor, drive circuit, and mechanical structure caused by short-term start-stop of the fan in scenarios with frequent fluctuations in operating conditions (such as urban traffic congestion), significantly extending the service life of the fan and improving system reliability.

[0045] For example, in congested traffic, frequent vehicle starts and stops cause rapid temperature fluctuations in the electric drive and battery systems within a small range, resulting in the fan being frequently commanded to start and stop within 5 minutes (e.g., starting 8 times). The controller detects that the number of starts and stops has exceeded a set threshold (e.g., 5 times / 5 minutes) and triggers protection logic. During the next 5-minute protection period, even if the instantaneous cooling demand drops to zero, the controller forces the fan to continue running at 1000 rpm and no longer responds to stop commands, thus preventing further frequent starts and stops.

[0046] Specifically, the controller uses a PID control algorithm to precisely control the actual speed of the electronic fan to the final target speed by adjusting the PID parameters.

[0047] In this scheme, the principle is to continuously collect the actual fan speed and compare it with the target speed to obtain an error signal e(t). The controller performs calculations based on the proportional (P), integral (I), and derivative (D) terms of the error, and dynamically adjusts the control signal output to the fan drive module, thereby forming a closed-loop negative feedback system that enables the actual speed to track the target speed quickly, smoothly, and accurately.

[0048] Compared to traditional open-loop lookup table control, PID control has stronger anti-interference capabilities, can adapt to changes in fan load, and offers high control precision. It enables continuous and smooth adjustment of fan speed, avoiding sudden noise spikes caused by speed jumps and improving ride comfort (NVH performance). Simultaneously, it reduces reliance on numerous preset parameter mapping relationships, lowering the calibration workload.

[0049] For example, when the target speed changes from 1500 rpm to 2000 rpm, the PID controller starts working. It detects a 500 rpm error between the actual and target speeds, and outputs a larger drive signal to accelerate the fan. As the actual speed approaches 2000 rpm, the P term weakens, while the I and D terms work together to prevent overshoot and stabilize the speed at the target value. Even if the vehicle acceleration causes changes in the airflow (interference), the PID controller can adjust the output in real time to ensure the fan speed remains stable at 2000 rpm.

[0050] This application also improves a method for controlling the speed of an integrated thermal management electronic fan in an electric vehicle according to the aforementioned system, comprising the following steps: S1. Data Acquisition Steps: Real-time acquisition of temperature information from the electric drive system, the power battery system, and the air conditioning system via sensor modules; S2. Demand Calculation Steps: Calculate the first required speed based on the temperature information of the electric drive system, calculate the second required speed based on the temperature information of the power battery system, and calculate the third required speed based on the pressure information of the air conditioning system. S3. Overall decision-making step: The first required speed, the second required speed and the third required speed are processed in a coordinated manner to generate the final target speed; S4. Control execution steps: Based on the final target speed, control the operation of the electronic fan through the fan drive module.

[0051] In this solution, a preferred and efficient implementation method for coordinating the first, second, and third required speeds during the overall decision-making process is the "maximum value comparison method." Specifically, the controller incorporates comparison logic to compare the values ​​of the three required speeds from the electric drive system, the power battery system, and the air conditioning system in real time. Subsequently, the controller executes the decision logic, directly setting the required speed with the largest value as the final target speed. For example, if the first required speed (electric drive system) is 800 rpm, the second required speed (power battery system) is 1200 rpm, and the third required speed (air conditioning system) is 1000 rpm, the controller will set the final target speed to 1200 rpm. This strategy ensures that at any given time, the system with the most urgent heat dissipation needs is always met, thus achieving both simplicity and efficiency in the control logic while guaranteeing the thermal safety of the entire vehicle.

[0052] Specifically, the overall decision-making steps include: Compare the first required speed, the second required speed, and the third required speed; The maximum value among the three is set as the final target rotational speed.

[0053] Specifically, the control execution steps also include a delayed shutdown step: When it is determined that the final target speed needs to change from a non-zero value to zero, the electronic fan is controlled to continue running at the preset minimum speed for a predetermined delay time before the shutdown operation is performed.

[0054] The specific implementation process is as follows: When the control logic determines that the final target speed needs to change from a non-zero value (e.g., 1500 rpm) to zero, it does not immediately cut off the power supply to the electric fan. Instead, the controller generates a delayed control command, which drives the electric fan into a predetermined low-speed maintenance phase. During this phase, the fan continues to run at a preset minimum speed (e.g., 800 rpm) for a predetermined delay time (e.g., 30 seconds). This delay time can be precisely controlled by a timer inside the controller. Only after this delay time has elapsed does the controller issue the final stop command, causing the electric fan to completely stop rotating. This process effectively utilizes residual airflow to dissipate residual heat in the system, avoiding system pressure surges caused by sudden fan shutdown.

[0055] Specifically, the control execution steps also include a protection step to prevent frequent start-stop operations: The number of start-stop cycles of the electronic fan within a preset time window is counted. If the number of times exceeds the preset safety threshold, the shutdown command is ignored, and the electronic fan is controlled to continue running at a speed not lower than the preset protection speed for the next protection time.

[0056] The frequent start-stop protection step included in the control execution process is implemented through a software algorithm. The controller internally maintains a start-stop event counter and a sliding time window timer. Each time the electric fan is started from a stopped state or stopped from a running state, it is recorded as a start-stop event. The algorithm continuously counts the total number of start-stop events occurring within a preset time window (e.g., 5 minutes). When the algorithm determines that this number exceeds a preset safety threshold (e.g., 5 times), it triggers the protection logic. During the protection period following the trigger (e.g., 5 minutes), the controller ignores any instructions that would reduce the final target speed to zero and forcibly outputs a control signal to keep the electric fan running at a speed not lower than the preset protection speed (e.g., 1000 rpm), thereby breaking the frequent start-stop cycle and protecting the fan components.

[0057] Specifically, in the control execution step, a PID control algorithm is used to make the actual speed of the electric fan stably track the final target speed through feedback adjustment.

[0058] In the control execution step, a PID control algorithm is used to achieve precise closed-loop control of the electric fan speed. Specifically, the controller continuously collects the actual speed value fed back by the speed sensor and compares it with the currently set final target speed to calculate the real-time error e(t). Subsequently, the controller calculates the error signal based on preset proportional coefficients (K_p), integral coefficients (K_i), and derivative coefficients (K_d) (the calculation formula can be expressed as: output = K_p * e(t) + K_i * ∫e(t)dt + K_d * de(t) / dt), dynamically generating and outputting a PWM (Pulse Width Modulation) signal to the fan drive module. Through this continuous feedback adjustment, the system can quickly eliminate speed deviations and ensure that the actual speed of the electric fan smoothly and stably tracks changes in the final target speed, effectively suppressing speed overshoot and fluctuations, and improving the smoothness and accuracy of control.

[0059] Please note to all technical personnel: Although the present invention has been described according to the specific embodiments above, the ideas of the present invention are not limited to this invention. Any modifications that utilize the ideas of the present invention will be included within the scope of protection of this patent.

Claims

1. An integrated thermal management electronic fan speed control system for electric vehicles, characterized in that... include: The sensor module is used to collect temperature information from the electric drive system, the power battery system, and the air conditioning system. The controller, which is signal-connected to the sensor module, is configured as follows: Receive information collected by the sensor module; The first required speed is determined based on the temperature information of the electric drive system, the second required speed is determined based on the temperature information of the power battery system, and the third required speed is determined based on the pressure information of the air conditioning system. The first required speed, the second required speed, and the third required speed are processed in a coordinated manner to determine the final target speed; And generate a control signal corresponding to the final target rotational speed; And a fan drive module, which is connected to the controller and the electronic fan signal, for driving the electronic fan to run at the final target speed according to the control signal.

2. The electric vehicle integrated thermal management electronic fan speed control system according to claim 1, characterized in that: The controller comprehensively processes the first required speed, the second required speed, and the third required speed, specifically including: The maximum value among the first required speed, the second required speed, and the third required speed is determined as the final target speed.

3. The electric vehicle integrated thermal management electronic fan speed control system according to claim 1, characterized in that: The controller is also configured to perform delayed shutdown control: When the final target speed changes from a non-zero value to zero, the fan drive module is controlled to drive the electronic fan to continue running at the preset minimum speed for a predetermined delay time, and then the electronic fan is controlled to stop.

4. The electric vehicle integrated thermal management electronic fan speed control system according to claim 1 or 3, characterized in that: The controller is also configured to perform protection against frequent start-stop cycles: Monitor the number of times the electronic fan starts and stops within a preset time window; If the number of start-stop cycles exceeds a preset threshold, the electronic fan will be controlled to maintain an operating speed of no less than the preset speed during the subsequent protection period, without responding to the command that the final target speed becomes zero.

5. The electric vehicle integrated thermal management electronic fan speed control system according to claim 1, characterized in that: The controller uses a PID control algorithm to precisely control the actual speed of the electronic fan to the final target speed by adjusting the PID parameters.

6. A method for controlling the speed of an integrated thermal management electronic fan in an electric vehicle based on the system described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1. Data Acquisition Steps: Real-time acquisition of temperature information from the electric drive system, the power battery system, and the air conditioning system via sensor modules; S2. Demand Calculation Steps: Calculate the first required speed based on the temperature information of the electric drive system, calculate the second required speed based on the temperature information of the power battery system, and calculate the third required speed based on the pressure information of the air conditioning system. S3. Overall decision-making step: The first required speed, the second required speed and the third required speed are processed in a coordinated manner to generate the final target speed; S4. Control execution steps: Based on the final target speed, control the operation of the electronic fan through the fan drive module.

7. The electric vehicle integrated thermal management electronic fan speed control method according to claim 6, characterized in that, The overall decision-making steps include: Compare the first required speed, the second required speed, and the third required speed; The maximum value among the three is set as the final target rotational speed.

8. The electric vehicle integrated thermal management electronic fan speed control method according to claim 6, characterized in that, The control execution steps also include a delayed shutdown step: When it is determined that the final target speed needs to change from a non-zero value to zero, the electronic fan is controlled to continue running at the preset minimum speed for a predetermined delay time before the shutdown operation is performed.

9. The method for controlling the speed of an integrated thermal management electronic fan in an electric vehicle according to claim 6 or 8, characterized in that, The control execution steps also include a protection step to prevent frequent start-stop operations: The number of start-stop cycles of the electronic fan within a preset time window is counted. If the number of times exceeds the preset safety threshold, the shutdown command is ignored, and the electronic fan is controlled to continue running at a speed not lower than the preset protection speed for the next protection time.

10. The method for controlling the speed of an integrated thermal management electronic fan in an electric vehicle according to claim 6, characterized in that, In the control execution step, a PID control algorithm is used to make the actual speed of the electric fan stably track the final target speed through feedback adjustment.

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