CN-121976965-A - Fan locked rotor detection method, device, medium and air conditioner

CN121976965ACN 121976965 ACN121976965 ACN 121976965ACN-121976965-A

Abstract

The invention discloses a method, a device, a medium and an air conditioner for detecting the locked rotor of a fan, which are characterized in that a target voltage signal is actively injected into the fan and a feedback current signal is monitored, and then the instantaneous voltage value, the instantaneous current value and the phase difference between the instantaneous voltage value and the instantaneous current value are extracted to calculate reactive power, and finally the fan locked-rotor state is predicted based on the combination of the reactive power and the phase difference double parameters. Because reactive power can reflect inductive load characteristics of motor windings, the phase difference is directly related to motor back electromotive force change, the rotor stalls and the back electromotive force disappears when the fan stalls, the reactive power can be rapidly increased, the phase difference approaches to a large value of pure inductance characteristics, the characteristic change of the two parameters is still obvious and stable under complex working conditions, obvious distortion can not be generated due to low speed, temperature fluctuation and motor aging, and the accuracy and the reliability of fan stall detection under the complex working conditions are greatly improved.

Inventors

Mai Haoqin
LI SHUANGLONG
XIONG JUN

Assignees

TCL空调器(中山)有限公司

Dates

Publication Date: 20260505
Application Date: 20260324

Claims (10)

1. The method for detecting the fan locked rotor is characterized by comprising the following steps: injecting a target voltage signal into a fan, and monitoring a feedback current signal of the fan; Determining an instantaneous voltage value of the target voltage signal, and extracting an instantaneous current value of the feedback current signal and a phase difference between the target voltage signal and the feedback current signal; calculating reactive power based on the instantaneous voltage value, the instantaneous current value, and the phase difference; And predicting the locked-rotor state of the fan based on the reactive power and the phase difference.
2. The method of claim 1, wherein the injecting the target voltage signal into the fan comprises: Acquiring a first offset taking the current moment as an angular frequency influence factor and a second offset taking the current moment as an amplitude influence factor; And injecting a target voltage signal into the fan, adjusting the basic angular frequency based on the first offset, and adjusting the basic amplitude based on the second offset, so that the angular frequency of the target voltage signal is kept as the target angular frequency, and the amplitude of the target voltage signal is kept as the target amplitude.
3. The fan stall detection method of claim 1, wherein the extracting the instantaneous current value of the feedback current signal and the phase difference between the target voltage signal and the feedback current signal comprises: phase-locking the target voltage signal based on a phase-locked loop to generate an in-phase reference signal and a quadrature reference signal which are the same frequency as the target voltage signal and are phase-locked; performing synchronous multiplication operation on the feedback current signal and the in-phase reference signal to obtain a first product signal, and performing synchronous multiplication operation on the feedback current signal and the quadrature reference signal to obtain a second product signal; Performing low-pass filtering processing on the first product signal to obtain a corresponding active current component, and performing low-pass filtering processing on the second product signal to obtain a corresponding reactive current component; Performing squaring operation on the square sum of the active current component and the reactive current component to obtain an instantaneous current value of the feedback current signal; and performing arctangent operation on the reactive current component and the active current component to obtain a phase difference between the target voltage signal and the feedback current signal.
4. The fan stall detection method of claim 1, wherein the calculating reactive power based on the instantaneous voltage value, the instantaneous current value, and the phase difference comprises: Calculating a sine value corresponding to the phase difference; multiplying the instantaneous voltage value, the instantaneous current value and the sine value to obtain a first operation value; Dividing the first operation value by a first parameter value to obtain reactive power.
5. The method for detecting a locked rotor of a wind turbine according to claim 1, wherein predicting the locked rotor state of the wind turbine based on the reactive power and the phase difference comprises: Normalizing the locked rotor related data, the reactive power and the phase difference to obtain a target locked rotor data set; carrying out weighted fusion on the target locked rotor data set to obtain a target characteristic value; Inputting the continuous target characteristic values into a time sequence prediction model for prediction to obtain a locked rotor risk value; And determining a target risk value interval to which the locked rotor risk value belongs, and determining a state corresponding to the target risk value interval as the locked rotor state.
6. The method according to claim 5, wherein when the stall condition is a near stall condition, the predicting the stall condition of the fan based on the reactive power and the phase difference further comprises: calculating a locked rotor trend quantized value based on a continuous locked rotor risk value and continuous target locked rotor data, wherein the target locked rotor data is any one data in the target locked rotor data set; and when the locked-rotor trend quantized value is larger than the quantized threshold value, controlling the fan to stop.
7. The method for detecting a locked rotor of a wind turbine according to claim 6, wherein calculating a locked rotor trend quantization value based on the continuous locked rotor risk value and the continuous target locked rotor data comprises: Performing difference value operation on the locked rotor risk values at adjacent moments to obtain a second operation value; Performing difference value operation on the target locked rotor data at adjacent moments to obtain a third operation value; dividing the second operation value by the third operation value to obtain a first ratio; And carrying out weighted summation on the first ratio values of different adjacent moments to obtain a locked rotor trend quantized value.
8. The utility model provides a fan locked-rotor detection device which characterized in that, fan locked-rotor detection device includes: The monitoring module is used for injecting a target voltage signal into the fan and monitoring a feedback current signal of the fan; The extraction module is used for determining the instantaneous voltage value of the target voltage signal and extracting the instantaneous current value of the feedback current signal and the phase difference between the target voltage signal and the feedback current signal; a calculation module for calculating reactive power based on the instantaneous voltage value, the instantaneous current value, and the phase difference; and the prediction module is used for predicting the locked-rotor state of the fan based on the reactive power and the phase difference.
9. A computer readable storage medium, characterized in that a computer program is stored, which, when being executed by a processor, causes the processor to perform the steps of the method according to any of claims 1 to 7.
10. An air conditioner comprising a memory and a processor, the memory storing a computer program which, when executed by the processor, causes the processor to perform the steps of the method of any one of claims 1 to 7.

Description

Fan locked rotor detection method, device, medium and air conditioner Technical Field The invention relates to the technical field of air conditioners, in particular to a method and a device for detecting the blocking of a fan, a medium and an air conditioner. Background The air conditioner fan can generate heavy current in the locked state due to the condition of locked rotation caused by dirt in the operation process, and the fan is extremely easy to overheat or even damage. However, under the complex working conditions of low-speed light load, severe fluctuation of ambient temperature, aging of a motor and the like, the electrical parameter performance of the traditional method is not obvious, and misjudgment or missed judgment of the locked rotor is extremely easy to occur. Disclosure of Invention Based on the above, it is necessary to provide a method, a device, a medium and an air conditioner for detecting the locked rotor of a fan, so as to solve the problem that the locked rotor is easy to misjudge or miss-judge under the complex working conditions of low-speed light load, severe fluctuation of ambient temperature, aging of a motor and the like in the prior art. In a first aspect, an embodiment of the present application provides a method for detecting a locked rotor of a fan, where the method includes: injecting a target voltage signal into a fan, and monitoring a feedback current signal of the fan; Determining an instantaneous voltage value of the target voltage signal, and extracting an instantaneous current value of the feedback current signal and a phase difference between the target voltage signal and the feedback current signal; calculating reactive power based on the instantaneous voltage value, the instantaneous current value, and the phase difference; And predicting the locked-rotor state of the fan based on the reactive power and the phase difference. In some embodiments of the present application, the injecting the target voltage signal into the fan includes: Acquiring a first offset taking the current moment as an angular frequency influence factor and a second offset taking the current moment as an amplitude influence factor; And injecting a target voltage signal into the fan, adjusting the basic angular frequency based on the first offset, and adjusting the basic amplitude based on the second offset, so that the angular frequency of the target voltage signal is kept as the target angular frequency, and the amplitude of the target voltage signal is kept as the target amplitude. In some embodiments of the application, the extracting the instantaneous current value of the feedback current signal and the phase difference between the target voltage signal and the feedback current signal comprises: phase-locking the target voltage signal based on a phase-locked loop to generate an in-phase reference signal and a quadrature reference signal which are the same frequency as the target voltage signal and are phase-locked; performing synchronous multiplication operation on the feedback current signal and the in-phase reference signal to obtain a first product signal, and performing synchronous multiplication operation on the feedback current signal and the quadrature reference signal to obtain a second product signal; Performing low-pass filtering processing on the first product signal to obtain a corresponding active current component, and performing low-pass filtering processing on the second product signal to obtain a corresponding reactive current component; Performing squaring operation on the square sum of the active current component and the reactive current component to obtain an instantaneous current value of the feedback current signal; and performing arctangent operation on the reactive current component and the active current component to obtain a phase difference between the target voltage signal and the feedback current signal. In some embodiments of the application, the calculating reactive power based on the instantaneous voltage value, the instantaneous current value, and the phase difference comprises: Calculating a sine value corresponding to the phase difference; multiplying the instantaneous voltage value, the instantaneous current value and the sine value to obtain a first operation value; Dividing the first operation value by a first parameter value to obtain reactive power. In some embodiments of the present application, the predicting the stall condition of the fan based on the reactive power and the phase difference includes: Normalizing the locked rotor related data, the reactive power and the phase difference to obtain a target locked rotor data set; carrying out weighted fusion on the target locked rotor data set to obtain a target characteristic value; Inputting the continuous target characteristic values into a time sequence prediction model for prediction to obtain a locked rotor risk value; And determining a target risk value interval to which the locked rotor ri