A new energy mine truck reducer cooling pump intelligent control method
Patent Information
- Application Number
- CN202611450727.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-09-18
- Publication Date
- 2026-10-23
Smart Images
Figure CN122960727A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of thermal management system control technology for powertrains of new energy mining trucks, and in particular to an intelligent control method for cooling pumps of reducers in new energy mining trucks. Background Technology
[0002] With the development of new energy vehicle technology, the reducer, as a crucial component of the power transmission system, generates significant heat during high-speed, high-load operation. The temperature of the lubricating oil inside the reducer directly affects the performance of gears, bearings, and seals. Excessive oil temperature leads to decreased lubricating oil performance, accelerated wear of components, and even impacts the overall vehicle's power performance and reliability. Therefore, active cooling of the reducer via an electronic cooling pump is necessary to maintain its operation within a suitable temperature range. The control strategy of the electronic cooling pump directly affects the reducer's thermal management effectiveness and the vehicle's reliability and economy.
[0003] Existing electronic cooling pump control systems for new energy vehicle reducers suffer from issues such as insufficient assessment of cooling capacity and a limited range of target speed controls. Specifically: Without monitoring the actual speed feedback of the electronic cooling pump, it is impossible to determine whether the cooling capacity has truly been established. When the electronic cooling pump fails to establish circulation properly due to malfunction or start-up failure, the vehicle can still be driven normally, causing the reducer to continue operating without effective cooling, posing a risk of overheating and damage. The electronic cooling pump cannot dynamically adjust according to changes in the reducer oil temperature. For example, it may maintain a high speed even when the oil temperature is already low, resulting in unnecessary energy consumption and affecting the overall vehicle economy. After the vehicle stops, a large amount of heat still accumulates inside the reducer. The existing control strategy immediately stops the cooling pump after the vehicle stops, which prevents the heat from being released in time, accelerates the thermal aging of the internal components of the reducer, and shortens the service life of the powertrain. Summary of the Invention
[0004] To address the aforementioned technical problems, this application proposes an intelligent control method for the cooling pump of a new energy mining truck reducer, comprising the following steps: S1: The VCU reads the status data of the electronic coolant pump in real time and determines whether to send an enable signal to the electronic coolant pump based on the status data. If an enable signal is sent, the electronic coolant pump starts running at a low speed at the default speed. Otherwise, it returns to S1 for continuous monitoring.
[0005] Preferably, the default speed is set to 80% of the rated speed of the electronic cooling pump.
[0006] Furthermore, after the vehicle is powered on and completes its self-test, the VCU (Vehicle Controller) reads status data, including the fault level signal and the ready signal of the electronic coolant pump, via the CAN bus; the fault level signal includes the current fault level of the electronic coolant pump; the ready signal includes status information on whether the electronic coolant pump has completed its initialization self-test and is ready to operate; when both of the following conditions (1) and (2) are met simultaneously, the VCU sends an enable signal to the electronic coolant pump: (1) The fault level signal of the electronic cooling pump indicates that there is no fault, that is, the fault level is zero; (2) The readiness signal of the electronic cooling pump is normal and ready; If either of the conditions (1) or (2) is not met, the VCU will not send an enable signal and will illuminate the instrument fault indicator light. The vehicle will maintain a speed limit of 0 km / h and return to S1 to continue reading the status data of the electronic cooling pump in real time and make a judgment.
[0007] The fault level signal is a signal output by the electronic coolant pump controller through the CAN bus after diagnosing its own operating status, and is directly read by the vehicle's VCU. Fault level zero represents no abnormality detected or no fault; fault level one represents a non-critical abnormality that does not affect the basic operation of the pump and does not affect the basic operating capability of the electronic coolant pump; fault level two represents an abnormality that affects the pump's operating performance; and fault level three represents a serious abnormality such as motor stall or power module overheating, in which the electronic coolant pump no longer has the ability to operate safely.
[0008] During the power-on startup phase, a pre-verification check is performed on the electronic cooling pump to check for faults and confirm its readiness. If there is a fault or it is not ready, the vehicle is directly restricted to avoid the risk of allowing the vehicle to run when the pump is not ready or in a faulty state, or the reducer to run without cooling. This ensures that the cooling system has the basis for operation from the source.
[0009] S2: After the electronic cooling pump starts running, it synchronously monitors the reducer lubricating oil temperature T_oil in real time, determines the oil temperature status based on T_oil, and performs dynamic adjustment and speed limiting processing of the target speed of the electronic cooling pump in parallel to obtain the target speed value N_target and the first vehicle speed constraint value V_limit_temp. The electronic cooling pump adjusts the current speed to the target speed value N_target.
[0010] The first vehicle speed constraint value represents the maximum vehicle speed allowed based on the current reducer lubricating oil temperature T_oil.
[0011] Furthermore, the VCU dynamically adjusts the target speed N_target of the electronic cooling pump based on the real-time lubricating oil temperature T_oil and performs speed limiting. Specifically: When the lubricating oil temperature T_oil is greater than or equal to the first temperature threshold, the target speed value N_target is set to the rated speed of the electronic cooling pump; When the lubricating oil temperature T_oil is greater than or equal to the second temperature threshold and less than the first temperature threshold, the target speed value N_target is set to 90% of the rated speed of the electronic cooling pump; When the lubricating oil temperature T_oil is less than the second temperature threshold, the target speed value N_target is set to 80% of the rated speed of the electronic cooling pump; When the lubricating oil temperature T_oil is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, an alarm is triggered, and the first vehicle speed constraint value V_limit_temp is set to the first speed limit value. When the lubricating oil temperature T_oil is greater than or equal to the fourth temperature threshold: a critical alarm is triggered, the first vehicle speed constraint value V_limit_temp is set to the second speed limit value, and the driver is reminded to stop and check immediately.
[0012] When the lubricating oil temperature T_oil is less than the third temperature threshold, no speed limit is applied to the first vehicle speed constraint value V_limit_temp.
[0013] Wherein, the first temperature threshold is higher than the second temperature threshold; the fourth temperature threshold is higher than the third temperature threshold; the third temperature threshold is higher than the first temperature threshold; the first speed limit is greater than the second speed limit, and the first speed limit does not exceed 15 km / h.
[0014] Preferably, the first temperature threshold is 80°C, the second temperature threshold is 60°C, the third temperature threshold is 110°C, and the fourth temperature threshold is 120°C; the first speed limit is 10 km / h, and the second speed limit is 5 km / h.
[0015] Preferably, the target speed N_target is updated every 100ms and sent to the electronic coolant pump controller via the CAN bus, and the electronic coolant pump internally tracks the target speed in a closed loop.
[0016] The pump speed is dynamically and progressively adjusted according to changes in oil temperature. The speed is reduced at low temperatures to decrease energy consumption, thus reducing the energy consumption of the pump during long-term high-speed operation while meeting heat dissipation requirements. At the same time, the vehicle speed is directly limited by oil temperature to reduce heat load when the oil temperature is too high, thus balancing heat dissipation requirements and vehicle economy.
[0017] S3: The VCU reads the actual speed feedback value N of the electronic cooling pump in real time and determines the second vehicle speed constraint value V_limit_speed based on the actual speed feedback value N.
[0018] The second speed constraint value represents the maximum vehicle speed allowed based on the current cooling capacity of the electronic cooling pump.
[0019] Furthermore, if the actual speed feedback value N is less than or equal to the first speed threshold, it is determined that the electronic cooling pump has not established an effective cooling cycle and the cooling capacity is seriously insufficient. The second vehicle speed constraint value V_limit_speed is set to 0km / h, and the vehicle is prohibited from driving. If the actual speed feedback value N is greater than the first speed threshold and less than or equal to the second speed threshold, it is determined that the cooling capacity of the electronic cooling pump is weak, and the second vehicle speed constraint value V_limit_speed is set as the second speed limit value, allowing the vehicle to crawl at extremely low speeds. If the actual speed feedback value N is greater than the second speed threshold and less than or equal to the third speed threshold, it is determined that the cooling capacity of the electronic cooling pump is average. The second vehicle speed constraint value V_limit_speed is set as the first speed limit value, allowing low-speed driving but limiting the vehicle speed to prevent the heat load from exceeding the cooling capacity. If the actual speed feedback value N is greater than the third speed threshold, the cooling capacity of the electronic cooling pump is determined to be normal, and V_limit_speed is not limited.
[0020] Wherein, the first speed threshold is lower than the second speed threshold; the second speed threshold is lower than the third speed threshold.
[0021] Preferably, the first speed threshold is 1000 rpm, the second speed threshold is 2000 rpm, and the third speed threshold is 3000 rpm.
[0022] By monitoring the actual speed feedback of the electronic cooling pump in real time, it is determined whether the cooling capacity has been truly established. When the electronic cooling pump fails to establish an effective cooling cycle due to malfunction or start-up failure, the vehicle is prohibited from driving or limited to a very low speed, thereby ensuring that the reducer does not operate under uncooled conditions.
[0023] S4: The VCU performs graded processing based on the fault level signal indicated in the status data to obtain the fault degradation coefficient η and the third vehicle speed constraint value V_limit_fault.
[0024] The fault degradation coefficient represents the degree of restriction on the speed of the electronic coolant pump, and the third vehicle speed constraint value represents the maximum vehicle speed allowed based on the current severity of the electronic coolant pump fault.
[0025] Furthermore, based on the fault level signal in the electronic coolant pump status data read in real time by the VCU, the faults are classified and processed as follows according to their severity: When the fault level signal indicates a fault level of zero or one, it means that the electronic coolant pump controller has not detected any abnormality or has detected a non-critical abnormality (slight communication fluctuations, instantaneous message loss, etc.). The VCU only performs instrument alarm processing when the fault level is one, and at the same time sets the fault degradation coefficient η to 1.0. The third vehicle speed constraint value V_limit_fault does not perform speed limit processing, and the vehicle drives normally.
[0026] When the fault level signal indicates a fault level of two, it means that the electronic coolant pump controller has detected an abnormality affecting the operating performance (excessive speed tracking deviation, abnormal drive current, etc.); the VCU illuminates the instrument fault light, and at the same time sets the fault degradation coefficient η to 0.5, and the third vehicle speed constraint value V_limit_fault to the first speed limit value.
[0027] When the fault level signal indicates a fault level of three, it means that the electronic coolant pump controller has detected a serious abnormality (motor stall, power module overheating, internal short circuit, etc.); the VCU sets the fault degradation coefficient η to 0, and the third vehicle speed constraint value V_limit_fault is set to the second speed limit value, allowing the vehicle to travel to a safe area at a low speed.
[0028] By classifying and handling faults, differentiated responses are achieved: minor faults trigger alarms, serious faults reduce speed, and fatal faults require shutdown protection. This maximizes vehicle availability while ensuring safety and avoids the drawbacks of traditional one-size-fits-all strategies.
[0029] S5: The minimum value of the first vehicle speed constraint value, the second vehicle speed constraint value and the third vehicle speed constraint value is taken as the final vehicle speed limit value, and the target speed value N_target is multiplied by the fault degradation coefficient η to obtain the final target speed value of the electronic coolant pump. The VCU and the electronic coolant pump controller perform speed limiting processing in parallel.
[0030] The speed limiting process specifically refers to the VCU adjusting the vehicle speed to the final speed limit, and the electronic coolant pump controller adjusting the electronic coolant pump speed to the final target speed value. The fault degradation coefficient η is a speed correction coefficient used to multiply the target speed value N_target obtained from the oil temperature condition determination based on the severity of the electronic coolant pump fault.
[0031] Furthermore, when the calculated final target speed of the electronic cooling pump is 0, the delayed shutdown in step S6 is not executed.
[0032] By minimizing the speed limit values across multiple dimensions, vehicle speed is restricted under three conditions: insufficient cooling capacity, excessively high oil temperature, and malfunction. The decision to minimize the speed limit across multiple dimensions ensures that the vehicle always operates in the safest state under multiple constraints. At the same time, the cooling pump speed is adjusted by combining the fault degradation coefficient, so that the impact of the fault is synchronously transmitted to the cooling pump output.
[0033] S6: When the vehicle speed drops to 0km / h and the gear is in N or P, it enters the shutdown preparation stage. At this time, the VCU reads the latest reducer lubricating oil temperature T_oil_stop again, determines the delay time, and delays the shutdown. If the conditions for entering the shutdown preparation stage are not met, it returns to step S2 to start execution and continuously monitors and adjusts.
[0034] The electronic cooling pump continues to run during the delay period. After the delay period ends, the machine is stopped. Specifically, the machine stops by resetting the final target speed value and turning off the electronic cooling pump. The higher the current lubricating oil temperature T_oil_stop, the longer the delay period.
[0035] Furthermore, when the current lubricating oil temperature T_oil_stop is less than or equal to the first temperature threshold, the delay time is determined to be the first preset duration; When the current lubricating oil temperature T_oil_stop is greater than the first temperature threshold and less than or equal to the third temperature threshold, the delay time is determined to be the second preset duration, and the electronic cooling pump maintains its current speed during the delay time. When the current lubricating oil temperature T_oil_stop is greater than the third temperature threshold, the delay time is determined to be the third preset duration, and the third preset duration is divided into two stages: during the first stage, the electronic cooling pump maintains the current speed unchanged, and during the second stage, the electronic cooling pump runs at 60% of the final target speed value. Wherein, the second preset duration is longer than the first preset duration; the third preset duration is longer than the second preset duration; and the duration of the first stage is shorter than the duration of the second stage.
[0036] Furthermore, if the vehicle speed is detected to be greater than 0 km / h or the gear is engaged in D / R gear again during the delay period, step S6 is immediately exited and the process returns to step S2 to begin execution.
[0037] Preferably, the first preset duration is 10 seconds, the second preset duration is 30 seconds, and the third preset duration is 45 seconds; the first stage is the first 15 seconds of the third preset duration, and the second stage is the last 30 seconds of the third preset duration.
[0038] By delaying shutdown according to oil temperature after stopping, the heat accumulated inside the reducer can be fully released by the coolant circulation after stopping, avoiding thermal shock and thermal aging problems caused by sudden cooling of high-temperature components; in high-temperature conditions, the speed is also reduced in stages to fully release the residual heat of the reducer, reduce thermal shock, and extend the service life of reducer components.
[0039] The beneficial effects of the intelligent control method for cooling pump of new energy mining truck reducer of the present invention are as follows: (1) By detecting the actual speed of the electronic cooling pump, it is determined whether the cooling capacity is established. When the cooling capacity is insufficient, the vehicle operation is restricted to avoid the reducer temperature rising rapidly due to lack of effective cooling; (2) The target speed is adjusted in stages according to the change of reducer oil temperature. While meeting the heat dissipation requirements, the energy waste caused by the long-term high-speed operation of the electronic pump is reduced, and the system economy is improved; (3) By classifying the fault level of the electronic pump, a multi-level protection strategy such as alarm, speed reduction, and stop control request is realized to improve the system fault adaptability; (4) By using the parking delay cooling strategy, the heat inside the reducer is fully released, the thermal aging of the parts is reduced, and the reliability of the powertrain is improved. Attached Figure Description
[0040] Figure 1 This is a schematic diagram of the overall workflow of the intelligent control method for the cooling pump of a new energy mining truck reducer according to the present invention; Figure 2 This is a flowchart illustrating step S2 of the intelligent control method for the cooling pump of a new energy mining truck reducer according to the present invention. Figure 3 This is a flowchart illustrating step S6 of the intelligent control method for the cooling pump of a new energy mining truck reducer according to the present invention. Detailed Implementation
[0041] To provide a further understanding of the purpose, structure, features, and functions of the present invention, detailed descriptions are provided below with reference to specific embodiments.
[0042] like Figure 1 As shown, the intelligent control method for the cooling pump of a new energy mining truck reducer according to the present invention includes the following steps: S1: The VCU reads the status data of the electronic coolant pump in real time and determines whether to send an enable signal to the electronic coolant pump based on the status data. If an enable signal is sent, the electronic coolant pump starts running at a low speed at the default speed. Otherwise, it returns to S1 for continuous monitoring.
[0043] The status data includes a fault level signal and a ready signal for the electronic cooling pump; the fault level signal includes the current fault level of the electronic cooling pump; the ready signal includes status information on whether the pump has completed its initialization self-test and is ready to operate.
[0044] When both of the following conditions (1) and (2) are met simultaneously, the VCU sends an enable signal to the electronic cool pump: (1) The fault level signal of the electronic cooling pump indicates that the fault level is zero; (2) The readiness signal for the electronic cooling pump is “Ready”.
[0045] S2: After the electronic cooling pump starts running, it synchronously monitors the reducer lubricating oil temperature T_oil in real time, determines the oil temperature status based on T_oil, and performs dynamic adjustment and speed limiting processing of the target speed of the electronic cooling pump in parallel to obtain the target speed value N_target and the first vehicle speed constraint value V_limit_temp. The electronic cooling pump adjusts the current speed to the target speed value N_target.
[0046] The first vehicle speed constraint value represents the maximum vehicle speed allowed based on the current reducer lubricating oil temperature T_oil.
[0047] like Figure 2 As shown, the VCU dynamically adjusts the target speed N_target of the electronic cooling pump based on the real-time lubricating oil temperature T_oil. Specifically: (1) If T_oil≥80℃, then let N_target be the rated speed of the electronic cooling pump and perform full-speed cooling; (2) If 60℃≤T_oil<80℃, then set N_target to 90% of the rated speed for moderate cooling; (3) If T_oil < 60℃, then set N_target to 80% of the rated speed for energy-saving low-speed operation; (4) If 110℃≤T_oil<120℃, then set the first vehicle speed constraint value V_limit_temp to 10km / h; (5) If T_oil≥120℃, then set the first vehicle speed constraint value V_limit_temp to 5km / h.
[0048] S3: The VCU reads the actual speed feedback value N of the electronic cooling pump in real time and determines the second vehicle speed constraint value V_limit_speed based on the actual speed feedback value N.
[0049] The second speed constraint value represents the maximum vehicle speed allowed based on the current cooling capacity of the electronic cooling pump.
[0050] (1) If N≤1000rpm, then set the second vehicle speed constraint value V_limit_speed to 0km / h and prohibit the vehicle from driving; (2) If 1000rpm < N ≤ 2000rpm, then set the second vehicle speed constraint value V_limit_speed to 5km / h; (3) If 2000rpm < N ≤ 3000rpm, then set the second vehicle speed constraint value V_limit_speed to 10km / h; (4) If N > 3000 rpm, then V_limit_speed will not be limited.
[0051] S4: The VCU performs graded processing based on the severity of the fault indicated by the fault level signal in the status data, and obtains the fault degradation coefficient η and the third vehicle speed constraint value V_limit_fault.
[0052] When the fault level signal indicates a fault level of zero or one, it means that the electronic coolant pump controller has not detected any abnormality or has detected a non-critical abnormality. At this time, the fault degradation coefficient η is set to 1.0, the third vehicle speed constraint value V_limit_fault is not subject to speed limit processing, and the vehicle can drive normally. When the fault level signal indicates a fault level of two, it means that the electronic coolant pump controller has detected an abnormality affecting the operating performance. At this time, the fault degradation coefficient η is set to 0.5, and the third vehicle speed constraint value V_limit_fault is set to 10km / h. When the fault level signal indicates a fault level of three, it means that the electronic coolant pump controller has detected a serious abnormality. At this time, the fault degradation coefficient η is set to 0, and the third vehicle speed constraint value V_limit_fault is set to 5km / h, allowing the vehicle to move to a safe area at a low speed.
[0053] S5: The minimum value of the first vehicle speed constraint value, the second vehicle speed constraint value and the third vehicle speed constraint value is taken as the final vehicle speed limit value, and the target speed value N_target is multiplied by the fault degradation coefficient η to obtain the final target speed value of the electronic coolant pump. The VCU and the electronic coolant pump controller perform speed limiting processing in parallel.
[0054] The VCU adjusts the vehicle speed to the final speed limit, and the electronic coolant pump controller adjusts the speed of the electronic coolant pump to the final target speed.
[0055] Furthermore, when the calculated final target speed of the electronic cooling pump is 0, the delayed shutdown in step S6 is not executed.
[0056] In this embodiment, when the first speed constraint value, the second speed constraint value, and the third speed constraint value are taken as minimum in S5, if any one of the first speed constraint value, the second speed constraint value, and the third speed constraint value is not subject to speed limit processing, then it is considered that the item does not participate in the minimum value calculation, and only the speed constraint value with a specific value has been set is taken as minimum.
[0057] In one embodiment, the first speed constraint value is not subject to speed limit processing, the second speed constraint value is 5km / h, and the third speed constraint value is not subject to speed limit processing. Then, the minimum value of the first speed constraint value, the second speed constraint value, and the third speed constraint value is 5km / h, and the final speed limit is 5km / h.
[0058] In another embodiment, if the first speed constraint value, the second speed constraint value, and the third speed constraint value are not subject to speed limiting, then the minimum value among the first, second, and third speed constraint values is taken as the speed limit, meaning the final speed limit is not subject to speed limiting.
[0059] S6: When the vehicle speed drops to 0km / h and the gear is in N or P, it enters the shutdown preparation stage. At this time, the VCU reads the latest reducer lubricating oil temperature T_oil_stop again, determines the delay time, and delays the shutdown. If the conditions for entering the shutdown preparation stage are not met, it returns to step S2 to start execution and continuously monitors and adjusts.
[0060] like Figure 3 As shown, when the conditions for entering the shutdown preparation are met, i.e., the vehicle speed drops to 0 km / h and the gear is in N or P: (1) If T_oil_stop≤80℃: Determine the delay time as 10s; (2) If 80℃ < T_oil_stop ≤ 110℃: the delay time is determined to be 30s, and the electronic cooling pump maintains its current speed during the delay time; (3) If T_oil_stop>110℃: Determine the delay time as 45s. For the first 15s, the electronic cooling pump maintains the current speed, and for the next 30s, it drops to 60% of the final target speed value to avoid thermal shock caused by sudden stop.
[0061] Example 1: This example illustrates the complete control process when the vehicle starts normally and the electronic cooling pump is working properly.
[0062] After the vehicle is powered on and completes its self-test, the S1 start-up enable determination step is executed. The VCU reads the fault level signal and ready signal reported by the electronic coolant pump via the CAN bus. Currently, the electronic coolant pump reports a fault level of 0 (no fault) and a ready signal of "Ready" (normal and ready). The VCU sends an enable signal to the electronic coolant pump controller via the CAN bus. If there is no fault indication on the instrument panel, the vehicle can be driven normally, and the electronic coolant pump starts operating at 80% of its rated speed (4000 rpm in this embodiment), i.e., 3200 rpm.
[0063] After the electronic coolant pump starts, S2 is executed to monitor oil temperature and perform dual-path control. The VCU collects the reducer lubricating oil temperature T_oil in real time. Currently, T_oil = 65℃, which is within the range of 60℃ ≤ T_oil < 80℃. The VCU outputs two control signals in parallel: the first signal sets the target speed value N_target to 90% of the rated speed of the electronic coolant pump, i.e., N_target = 0.9 × 4000 = 3600 rpm; the second signal, since the oil temperature has not reached the high-temperature speed limit threshold of 110℃, does not limit the speed of the first vehicle speed constraint value V_limit_temp. The VCU sends N_target = 3600 rpm to the electronic coolant pump controller via the CAN bus, and the electronic coolant pump adjusts its speed from 3200 rpm to 3600 rpm to continue operating.
[0064] Execute S3 to monitor cooling capacity and set a lower speed limit. The VCU reads the actual speed feedback value N of the electronic cooling pump in real time. If the current N = 3560 rpm (small deviation is allowed), and N > 3000 rpm, the VCU determines that the pump cooling capacity is normal, and V_limit_speed is not limited.
[0065] Execute the S4 fault classification handling procedure. The VCU detects that the current pump fault level is one, sets the fault degradation coefficient η=1.0, and sets V_limit_fault to no speed limit.
[0066] Perform the S5 integrated decision and final output steps. The VCU takes the minimum of the three speed limits, that is, the final speed limit V_limit_final=min( V_limit_temp, V_limit_speed, V_limit_fault)=no speed limit.
[0067] The final target engine speed is N_target_final = η × N_target = 1.0 × 3600 rpm = 3600 rpm. During normal vehicle operation with no speed limit, the electronic cooling pump operates at 3600 rpm.
[0068] After completing its transport task, the vehicle stops, its speed drops to 0 km / h, and the driver shifts the gear to P. Executing S6, the VCU detects the vehicle speed is 0 and the gear is in P, and enters the shutdown preparation phase.
[0069] The VCU reads the current oil temperature T_oil_stop as 95℃, which is within the range of 80℃ < T_oil_stop ≤ 110℃. The VCU executes a 30-second delay shutdown strategy: maintaining the current target speed for 30 seconds to allow the coolant to continuously circulate and remove the heat accumulated inside the reducer.
[0070] During the 30-second delay, the VCU detects that the vehicle speed remains at 0 and the gear remains in P. After the delay ends, the VCU stops sending enable signals and resets the final target RPM value, and the electronic cooling pump stops.
[0071] Example 2: The difference between this example and Example 1 is that it illustrates the protection process when the cooling capacity is insufficient, in the case of the electronic cooling pump failing to start or the actual speed being insufficient.
[0072] After the vehicle successfully starts in S1, the VCU sends an enable signal and a target speed of 3200 rpm. However, when executing S3, the VCU reads the actual pump speed feedback value N=500 rpm.
[0073] The VCU determines that N ≤ 1000 rpm and V_limit_speed = 0 km / h, therefore the vehicle is prohibited from driving. Simultaneously, the pump malfunction indicator light illuminates on the instrument panel. When S5 is executed, the final speed limit V_limit_final = 0 km / h, and the vehicle remains at the speed limit of 0 km / h, making it impossible to drive.
[0074] The driver notifies the maintenance personnel to check and repair the faulty electronic cooling pump. After the repair is completed, the process restarts from step S1.
[0075] Example 3: The difference between this example and Example 1 is that when the electronic cooling pump experiences a secondary fault, the graded processing steps implement downgrade protection, which is used to illustrate the fault graded processing process.
[0076] In this embodiment, the target rotational speed value N_target=3600 rpm and the first vehicle speed constraint value V_limit_temp calculated in S2 are unlimited speed, and the second vehicle speed constraint value V_limit_speed determined in S3 is also unlimited speed.
[0077] During normal vehicle operation, when S4 is executed, the VCU detects a fault level signal indicating that the fault level is two. At this time, the VCU illuminates the instrument fault light to alert the driver, sets the fault degradation coefficient η=0.5, and sets the third vehicle speed constraint value V_limit_fault=10 km / h.
[0078] Execute S5, the final speed limit V_limit_final = min(V_limit_temp, V_limit_speed, V_limit_fault) = 10 km / h, and the vehicle speed is limited to 10 km / h. The final target engine speed N_target_final = η × N_target = 0.5 × 3600 = 1800 rpm, and the electronic cooling pump operates at 1800 rpm.
[0079] The execution of S6 is the same as in Example 1.
[0080] The present invention has been described in the above-described embodiments; however, these embodiments are merely examples for implementing the present invention. It must be noted that the disclosed embodiments do not limit the scope of the present invention. Conversely, any modifications and refinements made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.
Claims
1. A method for intelligent control of a cooling pump in a new energy mining truck reducer, characterized in that, Includes the following steps: S1: The VCU reads the status data of the electronic cool pump in real time and determines whether to send an enable signal to the electronic cool pump based on the status data. If an enable signal is sent, the electronic cooling pump will start running at a low speed at the default speed; otherwise, it will return to S1 for continuous monitoring. VCU refers to the vehicle controller of the new energy mining truck; the status data includes the fault level signal and the readiness signal of the electronic cooling pump; the fault level signal includes the current fault level of the electronic cooling pump; the readiness signal includes status information on whether the electronic cooling pump has completed the initialization self-test and is ready to operate. S2: After the electronic cooling pump starts running, it synchronously monitors the reducer lubricating oil temperature T_oil in real time, determines the oil temperature status based on T_oil, and performs dynamic adjustment and speed limiting processing of the target speed of the electronic cooling pump in parallel to obtain the target speed value N_target and the first vehicle speed constraint value V_limit_temp. The electronic cooling pump adjusts the current speed to the target speed value N_target. The first vehicle speed constraint value represents the maximum vehicle speed allowed based on the current reducer lubricating oil temperature T_oil; the higher the lubricating oil temperature T_oil, the higher the target speed value N_target, and the lower the first vehicle speed constraint value V_limit_temp. S3: The VCU reads the actual speed feedback value N of the electronic cooling pump in real time and determines the second vehicle speed constraint value V_limit_speed based on the actual speed feedback value N; The second vehicle speed constraint value represents the maximum vehicle speed allowed based on the current cooling capacity of the electronic coolant pump; the lower the actual speed feedback value N, the lower the second vehicle speed constraint value V_limit_speed. S4: The VCU performs graded processing based on the fault level signal indicated in the status data to obtain the fault degradation coefficient η and the third vehicle speed constraint value V_limit_fault. The fault degradation coefficient represents the degree of limitation on the speed of the electronic coolant pump, and the third vehicle speed constraint value represents the maximum vehicle speed allowed based on the current severity of the electronic coolant pump fault. The more severe the fault, the lower the fault degradation coefficient, and the lower the third vehicle speed constraint value. S5: The minimum value of the first vehicle speed constraint value, the second vehicle speed constraint value and the third vehicle speed constraint value is taken as the final vehicle speed limit value, and the target speed value N_target is multiplied by the fault degradation coefficient η to obtain the final target speed value of the electronic coolant pump. The VCU and the electronic coolant pump controller perform speed limiting processing in parallel. The speed limiting process specifically refers to the VCU adjusting the vehicle speed to the final vehicle speed limit, and the electronic coolant pump controller adjusting the speed of the electronic coolant pump to the final target speed value. S6: When the vehicle speed drops to 0km / h and the gear is in N or P, it enters the shutdown preparation stage. At this time, the VCU reads the latest reducer lubricating oil temperature T_oil_stop again, determines the delay time, and delays the shutdown. If the conditions for entering the shutdown preparation stage are not met, it returns to step S2 to start execution and continuously monitors and adjusts. The electronic cooling pump continues to run during the delay period. After the delay period ends, the final target speed value is reset to zero and the electronic cooling pump is turned off. The higher the current lubricating oil temperature T_oil_stop, the longer the delay period.
2. The method according to claim 1, characterized in that, In S1, after the vehicle is powered on and completes the vehicle self-test, the VCU reads the status data of the electronic coolant pump through the CAN bus; when the following two conditions (1) and (2) are met simultaneously, the VCU sends an enable signal to the electronic coolant pump: (1) The fault level signal of the electronic cooling pump indicates that the fault level is zero; (2) The readiness signal of the electronic cooling pump is normal and ready; If either of the conditions (1) or (2) is not met, the VCU will not send an enable signal and will illuminate the instrument fault indicator light. The vehicle will maintain a speed limit of 0 km / h and return to S1 to continue reading the status data of the electronic cooling pump in real time and make a judgment.
3. The method according to claim 1, characterized in that, In S2, the VCU dynamically adjusts the target speed N_target of the electronic cooling pump based on the real-time lubricating oil temperature T_oil and performs speed limiting. Specifically: When the lubricating oil temperature T_oil is greater than or equal to the first temperature threshold, the target speed value N_target is set to the rated speed of the electronic cooling pump; When the lubricating oil temperature T_oil is greater than or equal to the second temperature threshold and less than the first temperature threshold, the target speed value N_target is set to 90% of the rated speed of the electronic cooling pump; When the lubricating oil temperature T_oil is less than the second temperature threshold, the target speed value N_target is set to 80% of the rated speed of the electronic cooling pump; When the lubricating oil temperature T_oil is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, an alarm is triggered, and the first vehicle speed constraint value V_limit_temp is set to the first speed limit value. When the lubricating oil temperature T_oil is greater than or equal to the fourth temperature threshold: a critical alarm is triggered, the first vehicle speed constraint value V_limit_temp is set to the second speed limit value, and the driver is reminded to stop and check immediately; When the lubricating oil temperature T_oil is less than the third temperature threshold, no speed limit is applied to the first vehicle speed constraint value V_limit_temp. Wherein, the first temperature threshold is higher than the second temperature threshold; the fourth temperature threshold is higher than the third temperature threshold; the third temperature threshold is higher than the first temperature threshold; the first speed limit is greater than the second speed limit, and the first speed limit does not exceed 15 km / h.
4. The method according to claim 3, characterized in that, In S3, if the actual speed feedback value N is less than or equal to the first speed threshold, it is determined that the cooling capacity of the electronic cooling pump is seriously insufficient, and the second vehicle speed constraint value V_limit_speed is set to 0km / h, prohibiting the vehicle from driving. If the actual speed feedback value N is greater than the first speed threshold and less than or equal to the second speed threshold, it is determined that the cooling capacity of the electronic cooling pump is weak, and the second vehicle speed constraint value V_limit_speed is set as the second speed limit value, allowing the vehicle to crawl at extremely low speeds. If the actual speed feedback value N is greater than the second speed threshold and less than or equal to the third speed threshold, it is determined that the cooling capacity of the electronic cooling pump is average. The second vehicle speed constraint value V_limit_speed is set as the first speed limit value, allowing low-speed driving but limiting the vehicle speed to prevent the heat load from exceeding the cooling capacity. If the actual speed feedback value N is greater than the third speed threshold, the cooling capacity of the electronic cooling pump is determined to be normal, and V_limit_speed is not subject to speed limiting. Wherein, the first speed threshold is lower than the second speed threshold; and the second speed threshold is lower than the third speed threshold.
5. The method according to claim 3, characterized in that, In S4, based on the fault level signal in the electronic coolant pump status data read in real time by the VCU, the fault is classified and processed as follows according to its severity: When the fault level signal indicates a fault level of zero or one, it means that the electronic coolant pump controller has not detected any abnormality or has detected a non-critical abnormality. The VCU only performs instrument alarm processing when the fault level is one, and at the same time sets the fault degradation coefficient η to 1.
0. The third vehicle speed constraint value V_limit_fault does not perform speed limit processing, and the vehicle drives normally. Level 2 fault: When the fault level signal indicates that the fault level is level 2, it means that the electronic coolant pump controller has detected an abnormality affecting the operating performance; the VCU illuminates the instrument fault light, and at the same time sets the fault degradation coefficient η to 0.5, and the third vehicle speed constraint value V_limit_fault to the first speed limit value; Level 3 fault: When the fault level signal indicates a fault level of three, it means that the electronic coolant pump controller has detected a serious abnormality; the VCU sets the fault degradation coefficient η to 0, and the third vehicle speed constraint value V_limit_fault is set to the second speed limit value, allowing the vehicle to travel to a safe area at a low speed.
6. The method according to claim 3, characterized in that, In S6, when the current lubricating oil temperature T_oil_stop is less than or equal to the first temperature threshold, the delay time is determined to be the first preset duration. When the current lubricating oil temperature T_oil_stop is greater than the first temperature threshold and less than or equal to the third temperature threshold, the delay time is determined to be the second preset duration, and the electronic cooling pump maintains its current speed during the delay time. When the current lubricating oil temperature T_oil_stop is greater than the third temperature threshold, the delay time is determined to be the third preset duration, and the third preset duration is divided into two stages: during the first stage, the electronic cooling pump maintains the current speed unchanged, and during the second stage, the electronic cooling pump runs at 60% of the final target speed value. Wherein, the second preset duration is longer than the first preset duration; the third preset duration is longer than the second preset duration; and the duration of the first stage is shorter than the duration of the second stage.
7. The method according to claim 1, characterized in that, If, during the delay period, the vehicle speed is detected to be greater than 0 km / h or the gear is engaged in D / R gear again, then step S6 is immediately exited and the process returns to step S2 to begin execution.