Research On The Thermal Characteristic Of A Flat Permanent-magnet Linear Synchronous Motor Feeding System

The traditional feeding system can not satisfy the need of high speed and precision machining increasingly. On the contrary, the direct feeding system of Permanent Magnet Linear Synchronous Motor (PMLSM) has the advantages in high speed, high precision, great trust and fast response, so it is applied in CNC machines more and more widely. The paper is based on and supported by the Science and Technology Project of Zhejiang Province (no.2009R50008). The force and heat characteristic of the linear motor is analyzed. On this basis, a three-dimension thermal model of PMLSM is created. The experimental research of the linear motor's thermal characteristic is completed.The background and the significance of the research are first stated. The development trend and the current research situations of the PMLSM feeding system are introduced in detail, and then the main contents of this dissertation are proposed.The space vector transfer law of the PMLSM is introduced in detail, then the d-q model and the trust equation of the PMLSM are deduced. On this basis, the dynamic analysis is carried out upon the linear motor in two different work conditions, and then the average effective current of linear motor is calculated. The heat exchange theory is introduced, which could provide a theoretical foundation for thermal field of the linear motor.A three-dimension finite element thermal model of flat linear motor is created. Then the thermal characteristic is simulated by the finite element software ansys. The simulation results show that the temperature rise is small under no-load condition, and high under load condition. The experimental research of the linear motor's thermal characteristic is completed under no-load condition, which verifies the correctness of the thermal model. Under load condition, the temperature rise of the linear motor is serious, and a cooling system should be designed for the linear motor.