Method for detecting running state of direct current water pump

Abstract

The invention belongs to the technical field of detection, in particular to a method for detecting the running state of a direct current water pump. The method for detecting the running state of the direct current water pump includes the steps that (1) a motor of the water pump starts to run, a system collects two-phase stator currents Ia and Ib of the motor, and the Ia and Ib are processed by Clarke conversion to obtain components I alpha and I beta in an alpha-beta axis system; (2) an alpha-beta two-phase static coordinate system is processed by Park conversion to obtain a d-q axis rotating coordinate system and corresponding components Id and Iq under the coordinate system; (3) after estimation is conducted by a flux observer, the current motor rotation speed n of the water pump is obtained; (4) a specific parameter showed in the description is compared with a set tolerance value sigma, and when it is recognized that the water pump is in an idling condition, the motor stops running. The method for detecting the running state of the direct current water pump has the advantages that through a relationship between the motor rotation speed n and the q axis current Iq, the idling running condition of the direct current water pump can be precisely judged, and the water pump can be switched off timely.

Description

technical field [0001] The invention belongs to the technical field of detection, and in particular relates to a method for detecting the running state of a DC water pump. technical background [0002] Due to the characteristics of high power density, high efficiency, small size and simple structure, the DC water pump adopts the position sensorless control scheme, which omits the complicated process of sensor installation and has higher reliability, making it more and more popular. more widely used. However, when the water pump is running dry, the impeller of the water pump is very easy to wear, causing the working flow of the water pump to fail to meet the customer's requirements. Therefore, a method that can accurately detect the running state of the water pump is needed. [0003] The traditional method judges by the effective current range value of the bus set at the minimum operating speed. The disadvantage is that it is difficult to distinguish idling and light load co...

AI Technical Summary

Problems solved by technology

However, when the water pump is running dry, the impeller of the water pump is very easy to wear, causing the working flow of the water pump to fail to meet customer requirements. Therefore, a method that can accurately detect the running state of the water pump is needed

[0003] The traditional method judges by the effective current range value of the bus set at the minimum operating speed. The disadvantage is that it is difficult to distinguish between idling and light load conditions, which is easy to cause misjudgment, and it is more likely to cause misjudgment as the input power voltage changes.

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