Researchand Application On PMSM Compressor Sensorless Control System For Air-condition

With the increasing prominence of energy, The concept of energy saving and low carbon life is put forward in the twelfth five year plan. In household appliances, air conditioning’s power consumption occupies the main part of the power consumption, compared with the variable-frequency air-conditioner, the fixed air conditioning’s power consumption and noise are larger, the efficiency is lower. As the core part of the air condition,the Permanent Magnet Synchronous Motor(PMSM) compressor’s efficiency can reach more than 90%, therefore, the compressor’s driven system is the mainstream of the variable-frequency air-conditioner, and the driving technology is also a hot topic in the current research.The structure of the PMSM compressor is enclosed.Considering the cost and operating environment, usually not installation position sensor in compressor, therefore how to estimate rotor without position sensor has become the basic conditions of the compressor’s operation. In this thesis, firstly, in different frequency range,using different position estimation methods, using the least squares algorithm in low speed,and the Sliding Mode Observer(SMO) in high frequency. Secondly, analysis and established the entire vector control system, using vector control methods based on id=0. Studying on the compressor start up mode, analyses the characteristics of three-stage open loop method. Considering the compressor torque current and load characteristics, the smoothly switch method is proposed on open-loop to closed-loop. With the characteristics of compressor’s load, especially in low speed, according to the real-time change of load, giving the current corresponding compensation fast. Suppresses the low-frequency vibration problem effectively. In addition, high frequency interference in SMO will affect the stable operation of the compressor when system operation under high frequency and heavy load, therefore, this paper puts forward the SMO observer with PLL, makes the estimated Angle in real time with actual rotor Angle, system can operation under high frequency and heavy load.Finally, in matlab/simulink platform,established and simulated the whole system. Carry some experiments on the platform based on TI control chip TMS320F28035, by comparing the data and indicators, verified the the design of the air conditioning compressor control system can satisfy the practical application of PMSM compressor control system. Eventually, the design of the compressor control system by this thesis has been successfully applied in the enterprise products, for the compressor performance, noise and lifetime test.