Papers by Author: Yong Chun Liang

Abstract: The detection of motor vibration can be used to evaluate the condition of motor. Furthermore the detection of motor vibration can be used to analyze the source of motor vibration and is helpful to reduce the motor vibration. Vibration is a cause of noise,so the vibration reduction is helpful to reduce the motor noise. Through analyzing the mechanism of motor vibration, a laptop computer and LabVIEW software are used to design the experimental system. the data acquisition system of vibration signal is composed of USB5935 data acquisition card, vibration acceleration sensor.LabVIEW is used to detect the vibration signal and record the vibration and realize the spectrum analysis. Through detecting and analyzing the vibration of the permanent magnet DC motor, It is proved that the motor vibration experimental system consisting of computer and LabVIEW can fully meet the requirements of electrical machine test and fault classification research.

Abstract: Partial discharge is one of the most common fault of power cable. It is of great significance to detect and analyze the condition of the power cable and locate the fault of the power cable. The model of partial discharge signal is constructed by a double exponential function. The simulation model of power cable with a middle fault is built by MATLAB SIMULINK. The transmission characteristic of partial discharge in different length of power cable and different types of power cable is simulated respectively. The simulation results show that the attenuation is proportional to the length of the same type of cable and the primary parameter of different type of power cables determines the attenuation.

Abstract: Inter-turn fault is the most probably fault in permanent motor. It is important to find the inter-turn fault and protect the permanent motor. Stator windings current is used to evaluate the inter-turn fault. A small resistance is connected with the permanent motor. The stator windings current is transferred to voltage and this signal is send to data acquisition system and transferred to digital signal. LabVIEW is used to control the data acquisition system and receive the digital signal. FFT is used to analyze the frequency character of the stator windings current and find the character of the inter-turn fault. Test shows that the permanent experimental system consisting of computer and LabVIEW can fully meet the requirements of permanent fault test and research.

Abstract: The detection of motor noise can be used to evaluate the condition of motor. Furthermore the detection of motor noise can be used to analyze the source of motor noise and is helpful to reduce the motor noise. Through analyzing the mechanism of motor noise, a laptop computer and LabVIEW software are used to design the experimental system. The hardware of noise detection system consists of an external microphone and sound card coming with the computer. LabVIEW is used to detect the noise signal and record the noise and realize the spectrum analysis. Through detecting and analyzing the noise of the permanent magnet DC motor and three-phase asynchronous motor, It is proved that the motor noise experimental system consisting of computer and LabVIEW can fully meet the requirements of electrical machine test and research.

Abstract: In the field of electric appliances’ reliability, the constant-stress accelerated-life-test is commonly used to test the reliability of electric appliances. A new analysis method based on constructed data is introduced to analyze the constant-stress accelerated-life-test data of electric appliances under Weibull distribution. The correlation between shape parameter and characteristic life is took into account and the estimated value of characteristic life is modified, which increase the model fitting optimization and improve the analysis precision. Moreover, the method avoids table lookup and is easy to be realized by computer software in the application of reliability engineering for electric appliances.