Research On PMSM Control System Applied In Air-conditioning Compressor

Permanent magnet synchronous motor(PMSM)have the advantage of high efficiency,simple structure,good speed regulation and small size.In the field of air conditioning compressor,the traditional asynchronous motor is replaced by PMSM due to its shortcomings,such as noise,low efficiency,small speed range.With the widely use of PMSM,the research of its control system is becoming more and more important.In the field of the control system of PMSM air-conditioning compressor,there are two important issues,one is how to get the position of the rotor without position sensor,the other one is how to deal with the side effect caused by load torque fluctuations of the compressor when the motor operate on low-speed.The main content of this paper is to study these two issues and the corresponding solutions.Firstly,we introduce the basic theory and methods of the control system of PMSM which include Park transformation/inverse Park transformation,Clack transformation/inverse Clack transformation,SVPWM control algorithm.Secondly this paper mainly introduce the sensorless angle estimation method.We introduce two different kinds of sensorless angle estimation method.The first one is the sensorless angle estimation method based on MRAS(Model Reference Adaptive System),it used when the PMSM running at high speed;The second one is sensorless angle estimation based on the high-frequency signal injection,it used when PMSM running at low speed.In this paper,a combination control method based on repetitive control and PI controller is proposed to solve the problems related to the torque ripple when the compressor running at low speed.Taking a specific air-conditioning compressor as an example,the design method based on zero-phase repetitive controller is introduced in detail.At last,the whole hardware and software platform of the system are introduced in detail.In the part of hardware platform,we introduce the design method of the power driver circuit and each module of the control board which is based on TMS320F28035.In the part of software platform,we introduce the design of the main loop and the design of each interrupt module with the flow chart.The simulation part of this paper is based on matlab/simulink platform,in this platform we complete the system simulation and each algorithm module simulation and the simulation waveforms are given to analysis these modules.The PMSM air-conditioning compressor control algorithm mentioned in this paper has been successfully applied in the project which is cooperated with enterprise.In the PMSM test platform,we operate a lot of tests which include launch,noise,service life speed regulation etc.These tests verified the feasibility and the practicability of the control system of the PMSM air-conditioning compressor.