Multi-point multi-stage temperature protection implementation method and device applied to automobile water pump

Abstract

The invention relates to a multi-point multi-stage temperature protection implementation method applied to an automobile water pump. The multi-point multi-stage temperature protection implementation method comprises the following steps that S1, main heating elements in a controller are confirmed; s2, temperature calibration is carried out on the main heating element to be tested in a laboratory, the calibrated temperature is graded according to the equal-interval temperature difference, and meanwhile the speed reduction proportion and the high-temperature shutdown protection temperature under different temperature grades are set; s3, NTC is arranged close to the main heating element; s4, performing temperature sampling on different NTC by the microprocessor, and calculating real-time temperature; and S5, the microprocessor judges the real-time temperature, and speed reduction or shutdown or normal operation is carried out according to a set value. The invention further provides an implementation device of the method. The implementation device comprises a microprocessor and a plurality of NTC. The overall temperature condition of the controller can be reliably obtained, so that temperature protection of the automobile water pump is achieved, the temperature condition in daily use can be recorded, early warning is conducted in advance when the temperature is abnormal, and the situation that the cooling function is suddenly lost is prevented.

Description

Technical Field

[0001] The invention relates to the technical field of automobile cooling water pumps, in particular to a method and a device for realizing multi-point and multi-stage temperature protection applied to automobile water pumps. Background Art

[0002] For high-power drive controllers, heat is inevitable when current flows through them. As long as the appropriate electronic components are selected under appropriate working conditions, they can work normally. However, under the influence of external conditions (such as the working ambient temperature or the working medium temperature), the temperature of electronic components will become high, which may affect the life of the device at the least, or even damage it on the spot and completely lose its function. Temperature detection and protection of the device is necessary. Although different devices are on the same PCB, the selection of devices with similar temperature levels is also considered during the selection. However, the internal resistance and the current flowing through are different, and the heat generated is different, resulting in some devices with very high temperatures and some with very low temperatures. Therefore, it is necessary to confirm the source of heat and appropriately reduce the output capacity under extreme temperature conditions to reduce heat and avoid further deterioration of external working conditions. The current mainstream temperature protection strategy: only sampling the internal temperature of the MCU, but the defects of using a single temperature point protection measure are as follows:

[0003] (1) Using a single temperature protection method, the temperature rise is large when running at full power. Under high critical temperature conditions, the cooling function is completely lost when the machine is shut down;

[0004] (2) A single temperature sampling source can only obtain the temperature near the current sampling source. The temperature estimation deviation of devices farther away is large, and the protection of devices farther away is not timely. Summary of the invention

[0005] In view of the above problems, the present invention provides a method and device for implementing multi-point and multi-level temperature protection for automobile water pumps, which can solve the unstable temperature protection of automobile water pump controllers and provide temperature warning.

[0006] The technical solution adopted by the present invention to solve the above technical problems is: a method for implementing multi-point multi-stage temperature protection for automobile water pumps, comprising the following steps:

[0007] S1, confirm the main heating components of the controller;

[0008] S2, the temperature of the main heating elements to be tested is calibrated in the laboratory, and the calibrated temperature is graded according to the temperature difference of equal intervals, and the speed reduction ratio and high temperature shutdown protection temperature under different temperature levels are set;

[0009] S3, arrange NTC close to the main heating element;

[0010] S4, the microprocessor samples the temperature of different NTCs and calculates the real-time temperature;

[0011] S5, the microprocessor compares the current real-time temperature in S4 with the set temperature in S2, and reduces speed, stops or operates normally according to the set value.

[0012] Preferably, step S5 specifically includes the following steps:

[0013] S501, if it is detected that the sampling temperature at this time is lower than the lowest set temperature of the lowest level in the calibration temperature, normal operation is performed;

[0014] S502, if it is detected that the sampling temperature at this time exceeds the highest level of high temperature shutdown protection temperature in the calibrated temperature, a warning message is fed back and the machine should be shut down for protection immediately;

[0015] S503, after the shutdown protection in step S502, if the sampled temperature is lower than the highest level high temperature shutdown protection temperature and higher than the lowest set temperature of the lowest level, the water pump returns to reduced speed operation;

[0016] S504, after the speed reduction operation in step S503, if the sampled temperature is lower than the lowest set temperature of the lowest level, all fault and warning information are cleared, the full speed is restored, and the process returns to step S501;

[0017] S505, steps S501 to S504 are continuously cycled.

[0018] Preferably, in step S503, the speed reduction operation executes speed reduction measures of different proportions according to different temperature levels.

[0019] The present invention also provides a multi-point and multi-level temperature protection implementation device for automobile water pumps, including a microprocessor and multiple NTCs. Each NTC is used for temperature sampling of a heat source and transmits a signal to the microprocessor. The microprocessor calculates the real-time temperature based on the sampled temperature and determines whether protection is required and feeds back information to the ECU. At the same time, the microprocessor controls the motor to implement protection.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention realizes high temperature protection by setting a multi-level high temperature protection mode and setting a plurality of temperature sampling sources, which can solve the unstable temperature protection of the automobile water pump controller and provide temperature early warning, which is specifically manifested as follows:

[0022] (1) When the outside temperature is high, the heat generated by the heat exchanger is gradually reduced to reduce the temperature rise, thereby ensuring a certain cooling function while protecting the heat exchanger from damage.

[0023] (2) Use multiple sampling temperature sources to evenly control the overall temperature and achieve overall protection;

[0024] (3) The arrangement of multiple temperature sampling sources reduces the risk of temperature protection failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the implementation of the device of the present invention;

[0026] Figure 2 It is a schematic diagram of the data processing logic of the microprocessor in the present invention. DETAILED DESCRIPTION

[0027] The following will be combined Figure 1-2 The present invention is described in detail. The exemplary embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention. The main heating element in this solution is the heat source.

[0028] A method for implementing multi-point and multi-stage temperature protection for an automobile water pump comprises the following steps:

[0029] S1, confirm the main heating components of the controller;

[0030] S2, the temperature of the main heating element to be tested is calibrated in the laboratory, and the calibrated temperature is graded according to the temperature difference with equal intervals. At the same time, the speed reduction ratio and high temperature shutdown protection temperature under different temperature levels are set. The speed reduction ratio is that the higher the absolute temperature of the heating element, the greater the speed reduction ratio. It needs to be calibrated according to actual needs. For example, under extreme high temperature conditions, the speed or power drops by 10%, 20%, 30%, 40%, and the temperature of the heating element will be significantly different. The purpose of different speed reduction measures is to make the absolute temperature of the heating element as low as possible as possible. The working temperature required by the specification book is lower than 150℃. For example, when the working temperature is 120℃ and full power, the temperature of the heating element reaches 150℃. At this time, the power drops by 10%, and the temperature rise will drop significantly by 5-6℃ compared with full power, which is lower than the maximum temperature requirement of the specification book. However, the performance of the water pump does not drop significantly, but it can still maintain normal function. At this time, the appropriate speed reduction has reduced the working temperature of the heating element. When the working temperature continues to rise, the speed reduction ratio continues to increase;

[0031] S3, arrange NTC close to the main heating element;

[0032] S4, the microprocessor samples the temperature of different NTCs and calculates the real-time temperature;

[0033] S5, the microprocessor compares the current real-time temperature in S4 with the set temperature in S2, and reduces speed or stops or runs normally according to the set value. The specific steps are as follows:

[0034] S501, if it is detected that the sampling temperature at this time is lower than the lowest set temperature of the lowest level in the calibration temperature, normal operation is performed;

[0035] S502, if it is detected that the sampling temperature at this time exceeds the highest level of high temperature shutdown protection temperature in the calibrated temperature, a warning message is fed back and the machine should be shut down for protection immediately;

[0036] S503, after the shutdown protection in step S502, if the sampled temperature is lower than the highest level high temperature shutdown protection temperature and higher than the lowest set temperature of the lowest level, the water pump returns to the reduced speed operation. In the specific reduced speed operation process, different proportions of reduced speed measures are executed according to the status of different temperature levels;

[0037] S504, after the speed reduction operation in step S503, if the sampled temperature is lower than the lowest set temperature of the lowest level, all fault and warning information are cleared, the full speed is restored, and the process returns to step S501;

[0038] S505, steps S501 to S504 are continuously cycled.

[0039] The present invention also provides a multi-point and multi-level temperature protection implementation device for automobile water pumps, including a microprocessor and multiple NTCs. Each NTC is used to sample the temperature of the heat source and transmit the signal to the microprocessor. The microprocessor calculates the real-time temperature based on the sampled temperature and determines whether protection is needed and feeds back the information to the ECU. At the same time, the microprocessor controls the motor to implement protection.

[0040] During the implementation, if there are three main heating elements, we will set up three corresponding NTCs. The microprocessor will sample the temperature of the three NTCs and calculate the real-time temperature 1, temperature 2, and temperature 3 respectively. The temperature is graded with the temperature difference at equal intervals. For example, in this embodiment, it is divided into three temperature levels: 130-140 degrees is high temperature level 1, 140-150 degrees is high temperature level 2, and greater than 150 degrees is high temperature level 3. At the same time, the speed reduction ratio under different temperature levels is set, and the high temperature shutdown protection temperature is set. After that, the current real-time temperature is compared with the set temperature, and the speed is reduced or shut down according to the set value, or it is operated normally, such as Figure 2As shown. In actual application, we can also calculate average temperature 1, average temperature 2, and average temperature 3 (long-term average value, the initial value can be calibrated through experiments), and calibrate the temperature. At the beginning, calibrate the stable temperature at maximum power under rated conditions. If the real-time temperature is always near this calibration temperature, record the normal working temperature at intervals, and record the average current / power at maximum speed, calculate the average value and save it. If the power / current during operation is almost unchanged, but the temperature and the average temperature recorded between are much higher, but lower than the shutdown protection temperature, the possible reasons are: the heating element heats up more and the external working conditions change, then feedback sends out a warning message to remind you to check, and it is still operating normally or at a reduced speed.

[0041] The technical solutions provided by the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the embodiments of the present invention. The description of the above embodiments is only applicable to help understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, according to the embodiments of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for implementing multi-point and multi-level temperature protection for automobile water pumps, characterized in that: The following steps are involved: S1, confirm the main heating components of the controller; S2, the temperature of the main heating elements to be tested is calibrated in the laboratory, and the calibrated temperature is graded according to the temperature difference of equal intervals, and the speed reduction ratio and high temperature shutdown protection temperature under different temperature levels are set; S3, arrange NTC close to the main heating element; S4, the microprocessor samples the temperature of different NTCs and calculates the real-time temperature; S5, the microprocessor compares the current real-time temperature in S4 with the set temperature in S2, and reduces speed, stops or operates normally according to the set value.

2. The method for implementing multi-point and multi-stage temperature protection for automobile water pumps according to claim 1 is characterized in that: Step S5 specifically includes the following steps: S501, if it is detected that the sampling temperature at this time is lower than the lowest set temperature of the lowest level in the calibration temperature, normal operation is performed; S502, if it is detected that the sampling temperature at this time exceeds the highest level of high temperature shutdown protection temperature in the calibrated temperature, a warning message is fed back and the machine should be shut down for protection immediately; S503, after the shutdown protection in step S502, if the sampled temperature is lower than the highest level high temperature shutdown protection temperature and higher than the lowest set temperature of the lowest level, the water pump returns to reduced speed operation; S504, after the speed reduction operation in step S503, if the sampled temperature is lower than the lowest set temperature of the lowest level, all fault and warning information are cleared, the full speed is restored, and the process returns to step S501; S505, steps S501 to S504 are continuously cycled.

3. The method for implementing multi-point and multi-stage temperature protection for automobile water pumps according to claim 2 is characterized in that: In step S503, the speed reduction operation executes speed reduction measures of different proportions according to the states of different temperature levels.

4. A multi-point multi-stage temperature protection implementation device for automobile water pumps, characterized in that: It includes a microprocessor and multiple NTCs. Each NTC is used to sample the temperature of the heat source and transmit the signal to the microprocessor. The microprocessor calculates the real-time temperature based on the sampled temperature and determines whether protection is needed and feeds back the information to the ECU. At the same time, the microprocessor controls the motor to implement protection.

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