Modeling Of A Motor In High Frequency In The Case Of Data Transmission By Power Line

This paper mainly does research on the modeling of the power line communication in the motor driving system. Through the analysis of the characteristics of the information transmission, the transfer model of the power line is established. What's more, the establishment of the motor model is also discussed, especially when it is under the condition of characteristics of the motor input impedance with high frequency. Thus, in this paper the identification methods of the AC machine modeling parameters and the simulation methods are brought up.First of all, the paper offers a review of the development of the power line carries communication technique including HomePlug1.0 standards, the development abroad, and its development and the formulation of standards in China.Secondly, the electrical drive system referred in the paper includes converter, output filter, power line, PLC modem and motor, etc. When the frequency of the signals is relatively high, the input impedances of the motor and the transmission power line are functions of the frequency. In the case of high frequency, the changes of impedances of the motor and the power line affect channel characteristics of the whole power line carrier communication. During the modeling of the power line channel, the paper employs the model based on the two port network, and uses the RLCG unit model to establish the distributed model with two conductions.The paper also analyzes the main problems in PLC system, the noise characteristics, attenuation characteristics and impedance characteristics of the channel. For the sake of the stable and reliable communication, the modern communication technologies, such as OFDM, should be taken into account.The third part mainly discusses about the establishment of the AC motor. Through the comparative research, the paper chooses the improved signal coupling model for the simulation research. Meanwhile, it also introduces the instantaneous equivalent model of the asynchronous motor, and makes a further exploration toward the internal parameters of the motor.The last of the research is the about the experimental measurement analysis and simulation. The experimental measurement is done to the power of 3kw and 300w motors and the motor cable with two cores, from which the input impedance and phase curves of the electric motors and cable are illustrated. By the use of the analysis method based on the impedance formula, the minimization error method and the most optimized method based on Matlab with PSO, the parameters can be identified. Put the gained parameters into the model, and the impedance model of the motor thus comes into formation, and so is functions of the motor impedance to the channel transmission. The accuracy of the motor model can be shown through the approximation ratio between the simulation curve and the measurement curve.