阅读说明：本技术 一种电子水泵干转保护方法 (Dry-running protection method for electronic water pump ) 是由 崔鹏程 范志猛 赵华 刘志东 常培松 崔鑫 刘建国 孙兆 曹英杰 郭富成 李博文 于 2020-05-09 设计创作，主要内容包括：本发明公开了一种电子水泵干转保护方法,包括首先对电流值短时峰值设置滤波范围进行过滤,短时峰值不作为判定依据,在电子水泵首次识别干转时,通过对本发明所述方法的执行,对电子水泵进行降速、升速重新检测等多个确认过程,最终判定是否缺水干转。本发明可实现避免误判的产生,对电子水泵进行保护,同时避免电子水泵误判停机对冷却系统造成的功能影响。(The invention discloses a dry-running protection method for an electronic water pump, which comprises the steps of firstly setting a filtering range for a short-time peak value of a current value to be filtered, wherein the short-time peak value is not used as a judgment basis, and when the electronic water pump identifies dry running for the first time, performing a plurality of confirmation processes such as speed reduction, speed rise re-detection and the like on the electronic water pump by executing the method disclosed by the invention, and finally judging whether the dry running is lack of water. The invention can avoid the generation of misjudgment, protect the electronic water pump and simultaneously avoid the functional influence on the cooling system caused by the misjudgment and shutdown of the electronic water pump.)

1. A dry-running protection method of an electronic water pump is characterized by comprising the following steps: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

setting a current value filtering range t and setting a current protection threshold I_DryRun；

Raising the speed of the electronic water pump to a test rotating speed N_TestDryRunTime period T₀The current of the internal electronic water pump is lower than a protection threshold I_DryRunWhen the electronic water pump is started, the electronic water pump automatically reduces the speed to a specific rotating speed N₁In the operating period T₁Then, the electronic water pump is accelerated to the testing rotating speed N_TestDryRunDetect T again₀The current of the internal electronic water pump is circulated for n times according to the step;

judging T in n detection processes₀Whether the current of the internal electronic water pump is lower than a protection threshold I_DryRun：

When T is detected₀The current of the internal electronic water pump is higher than a protection threshold I for the first time_DryRunWhen the electronic water pump works normally, the electronic water pump stops detecting according to the signal;

when T is detected₀The current of the internal electronic water pump is always lower than a protection threshold I_DryRunWhen the electronic water pump is stopped, the fault code is reported, and at interval time T₂Then, the electronic water pump is set and restarted, and is accelerated to the testing rotating speed N_TestDryRunAnd performing dry rotation detection again, and if the dry rotation fault is still judged, reducing the speed of the electronic water pump to a specific rotating speed N1 for a continuous operation time period T₃Then the machine is stopped and is not restarted.

2. The electronic water pump dry-running protection method of claim 1, characterized by comprising the following steps: the current value is filtered to be the current value of the short-time peak value.

3. The electronic water pump dry run protection method of claim 1 or 2, characterized by comprising: the current protection threshold I_DryRunThe phase current in the electronic water pump.

4. The electronic water pump dry run protection method according to any one of claim 3, characterized in that: the test rotation speed N_TestDryRunIs a fixed rotational speed.

5. The electronic water pump dry run protection method of any one of claims 1, 2 or 4, wherein: the electronic water pump dry rotation detection is carried out when the electronic water pump is started for the first time after power-on reset.

6. The electronic water pump dry run protection method of claim 5, wherein: the specific rotating speed N₁Less than the test speed N_TestDryRun。

7. The electronic water pump dry run protection method of claim 1 or 6, characterized by comprising: in the interval period T₂Then, the detection is carried out again, and when the current of the electronic water pump in T0 is higher than the protection threshold I for the first time in the detection process_DryRunAnd eliminating the fault code, normally operating the electronic water pump according to the signal, and stopping detection.

8. The electronic water pump dry run protection method of claim 7, wherein: and the fault code is sent to the automobile instrument desk.

9. The electronic water pump dry run protection method according to any one of claims 1, 2, 4, 6 or 8, wherein: the current of the electronic water pump is always higher than a protection threshold I within at least 200ms_DryRunThe electronic water pump can normally operate according to the signal and stop detecting.

10. The electronic water pump dry run protection method of claim 9, wherein: the number of cycles n is at least greater than 2.

Technical Field

The invention relates to the technical field of electronic water pumps of engines, in particular to a dry-running protection method for an electronic water pump.

Background

Along with the development of the technology, an electrical control element replaces a traditional mechanical control element, an electronic water pump comprises a motor, a controller, a bearing, a sealing element and the like, the working and running processes of the electronic water pump are summarized, and all the components need cooling liquid to be cooled so as to achieve an ideal working state; once the coolant is lost, the components are damaged by high temperature, such as motor ablation, controller ablation, seal ablation, etc. Therefore, electronic products are generally provided with a dry-running protection method, and the change of the load at the impeller end is identified through the running current of the motor to judge whether the cooling liquid is lost.

In the conventional electronic water pump dry-running protection method, through system calibration, the current consumed by the water pump at a specific rotating speed is set as a threshold value, namely when the electronic water pump runs to the rotating speed, if the current value is lower than the threshold value, the load of the impeller end of the electronic water pump is considered to be low at the moment, the electronic water pump is in a water shortage state, the electronic water pump is immediately shut down, and meanwhile, a fault code is sent to an ECU of the whole vehicle. The control mode has misjudgment, because the electronic water pump has the same power output state, P is UI, the current is inversely proportional to the voltage, namely the larger the voltage is, the smaller the current is, but the output power of the water pump is the same at the moment, namely the rotating speed is constant; when the voltage of the whole vehicle system changes instantaneously, the current also has an instantaneous low peak value, the phenomenon generally exists in a new energy hybrid vehicle type at the present stage, and the electronic water pump is stopped at the moment, which is misjudged. In addition, when the cooling liquid is added again in the after-sale maintenance of the vehicle, gas is inevitably existed in the system, the exhaust operation is generally carried out, and in the exhaust process, when the gas passes through the impeller of the electronic water pump, the misjudgment is also existed, and a false alarm is sent out.

Disclosure of Invention

This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. In this section, as well as in the abstract and the title of the invention of this application, simplifications or omissions may be made to avoid obscuring the purpose of the section, the abstract and the title, and such simplifications or omissions are not intended to limit the scope of the invention.

The invention is provided in view of the above and/or the problems existing in the existing electronic water pump dry-running protection method.

Therefore, the problem to be solved by the invention is how to prevent the electronic water pump from performing water shortage dry rotation.

In order to solve the technical problems, the invention provides the following technical scheme: a dry-running protection method for an electronic water pump comprises the steps of setting a current value filtering range t and setting a current protection threshold I_DryRun(ii) a Raising the speed of the electronic water pump to a test rotating speed N_TestDryRunTime period T₀The current of the internal electronic water pump is lower than a protection threshold I_DryRunWhen the electronic water pump is started, the electronic water pump automatically reduces the speed to a specific rotating speed N₁In the operating period T₁Then, the electronic water pump is accelerated to the testing rotating speed N_TestDryRunDetect T again₀The current of the internal electronic water pump is circulated for n times according to the steps. Judging T in n detection processes₀Whether the current of the internal electronic water pump is lower than a protection threshold I_DryRun: when T is detected₀The current of the internal electronic water pump is higher than a protection threshold I for the first time_DryRunWhen the electronic water pump works normally, the electronic water pump stops detecting according to the signal; when the current of the electronic water pump in T0 is always lower than a protection threshold I in the detection process_DryRunWhen the electronic water pump is stopped, the fault code is reported, and at interval time T₂Then, the electronic water pump is set and restarted, and is accelerated to the testing rotating speed N_TestDryRunAnd carrying out dry rotation detection again, and if the dry rotation fault is still judged, reducing the speed of the electronic water pump to a specific rotating speed N₁Sustained operation period T₃Then the machine is stopped and is not restarted.

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: the current value is filtered to be the current value of the short-time peak value.

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: the current protection threshold I_DryRunThe phase current in the electronic water pump.

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: the electronic water pump dry rotation detection is carried out when the electronic water pump is started for the first time after power-on reset.

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: the specific speed N1 is less than the test speed N_TestDryRun。

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: in the interval period T₂Then, detecting again, when T is detected₀The current of the internal electronic water pump is higher than a protection threshold I for the first time_DryRunAnd eliminating the fault code, normally operating the electronic water pump according to the signal, and stopping detection.

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: and the fault code is sent to the automobile instrument desk.

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: the current of the electronic water pump is always higher than a protection threshold I within at least 200ms_DryRunThe electronic water pump can normally operate according to the signal and stop detecting.

As a preferable scheme of the electronic water pump dry-running protection method of the invention, the method comprises the following steps: the number of cycles n is at least greater than 2.

The method has the advantages that when the electronic water pump identifies the dry running for the first time, through the execution of the method, a plurality of confirmation processes such as speed reduction, speed rise re-detection and the like are carried out on the electronic water pump, whether the electronic water pump runs dry due to water shortage is finally judged, so that the generation of misjudgment is avoided, the electronic water pump is protected, and meanwhile, the functional influence on a cooling system caused by misjudgment shutdown of the electronic water pump is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise. Wherein:

fig. 1 is a diagram illustrating a variation of an actual operating speed of an electronic water pump in the dry-run protection method of the electronic water pump.

Fig. 2 is a logic diagram of the dry-running protection method of the electronic water pump according to the present invention.

Fig. 3 is a logic diagram of a dry run protection method of an electronic water pump in the prior art.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Furthermore, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.