Abstract — The stereo garage can adopt linear induction motors (LIMs) as the drive part of translation due to simple construction, low cost and high speed. In lifting platform, several LIMs and electromagnets are respectively installed below and above the crossbeam. With the moving of crossbeam driven by LIMs and the attraction of electromagnets, the cars can be rapidly stored or taken. On the top of stereo garage, the LIMs also can be adopted to drive the lognitudinal moving mechanism in order to realize the movement of lifting platform in longitudinal direction, so the car parking capacity is significantly improved. By analytical equivalent circuit method, the LIM of this application is designed, and the influences of structure parameters are also investigated. Based on FE method, the dynamic performances are calculated and the effectiveness of analytical design is also validated. Finally, the measured results of prototype validate predicted results. Now the designed LIMs are successfully applied in the lifting platform of 8-layers stereo garage.36411
I.  INTRODUCTION The stereo garages are very important to big cities due to population and vehicle rapidly increasing. In recent years, more and more stereo garages are applied in the world, and their capacity is also bigger and bigger. Therefore, the vehicle access speed becomes one of key performances. However, to traditional stereo garages, it is limited due to the intermediate conversion devices, such as chains and gears [1-2].  In order to realize the direct drive without these intermediate devices, the strong candidate is linear induction motors (LIMs). Therefore, the research of the stereo garages driven by LIMs has quite strong practical significance [3]. LIMs are widely applied in transportation, logistics and industry due to simple construction and low cost than other linear motor format. They have different structure types, such as single-side, double-side, tubular, disc and arc. In the practical application, the single-side compound-secondary LIMs are more popular, and attract a lot of research. In literature, several papers investigate thrust force and normal force under constant voltage excitation or constant current excitation [4]–[8]. Some papers adopt an analytical electromagnetic field solution. The biggest disadvantage is the calculation accuracy that is affected by many simplifications for solving the complex mathematical operation. In order to improve the calculation accuracy and consider the transverse edge effect, the finite element (FE) method is often adopted [9]–[10].  The design of LIMs for stereo garages is rarely investigated. Due to the required low operating velocity at this application, the LIMs should be designed with low rated frequency, which is different to normal LIMs. Although there is corresponding research of the normal LIMs, it should be investigated because this LIM is operated at low frequency and full voltage, which should lower the current as possible to avoid magnetic field saturation.  This paper mainly investigates the drive system of stereo garages, and then obtains the design specifications of LIM. Based on analytical equivalent method, the LIM is designed and the influences of structure parameters are investigated. After that, its dynamic performance is analyzed based on FE method. The predicted results are also validated by prototype measurement. II.  LIFTING PLATFORM DRIVEN BY LIMS Fig.1 shows the lifting platform with LIMs in stereo garage, which is located in the middle of stereo garage. It includes crossbeam, car carrying plate, several electromagnets and LIMs. The movable primaries of all same LIMs in parallel are fixed below of the crossbeam, and the stationary secondaries of LIMs are mounted on the lifting platform. The air gap length is kept by two linear bearings. Above the crossbeam, the electromagnets are mounted, which are supplied with DC current. The corresponding cores are attached to the side of each car carrying plate. Compared with traditional stereo garage, this stereo garage makes all electrical equipments mounted on lifting platform, so the structure of parking space is very simple because it only has the car carrying plate. 36411 立体车库电动机研究英文文献和中文翻译:http://www.youerw.com/fanyi/lunwen_34847.html