2(8), 2017

Cao Junci1, Li Weili1, Wu Zhigang1, Yang Shaohua2
1-School of Electrical Engineering, Beijing Jiaotong
University, Beijing, 100044, China
2-Jiang Su Weiteli Motor Limited By Share Ltd, Taizhou
225318, China

POWER TRACTION AND SUSPENSION SYSTEM
OF MAGLEV TRAIN


I. Introduction
Maglev train has the advantages of low energyconsumption, low noise, strong climbing ability, high operationspeed, large acceleration space and more comfortable than wheel railtrain. And in China, the distance between cities is different fromJapan and other countries. Under such conditions only the maglevtrain has the advantage of competing with the aircraft.Since 2002, the world's first commercial maglev train lineoperators started running in Shanghai. By 2016, China's firstcommercial operation in low speed maglev demonstration line whichhas completely independent property rights - Changsha MaglevExpress Start running.

II. Power Traction and Suspension Systems
2.1 Electro Magnetic Suspension
As shown inFig. 1, the suspension principle and drive of long stator forEMS is based on the attractiveness of regular conductors magnet andferromagnetic long stator rail. The electromagnet is dynamicallyadjusted by the air gap sensor and the acceleration sensor so that theair gap can be maintained at 8 mm and 12 mm in accordance withthe operating speed to ensure safe life characteristics.
2.2. Electro Dynamic Suspension
As shown in Fig. 2, EDS is based on the principle ofelectromagnetism magnetic levitation. The superconducting magnetcoils are laterally mounted at the end of each unit and at thetransition, and induced eddy currents in the track coil. The train cansuspension when increase to a certain speed. The height of thesuspended air gap is between 100 mm and 150 mm, and theadjustment device can be omitted. Since the principle of magneticflux leakage is large, we need to shield passengers.

Fig. 1. EMS

Fig. 2. EDS



III. Comparison of Two Electromagnetic Systems
EMS covers a large range of operation, in smaller trafficand lower speed can also be used economically. It's economic onlythe traffic volume is very large for Japan's EDS because of the highinvestment. Table 1 compares the differences between the twosystems.
Table 1. Differences Between the Two Systems



Information about authors:
Cao Junci, School of Electrical Engineering, Beijing Jiaotong
University, Beijing, 100044, China
Li Weili, School of Electrical Engineering, Beijing Jiaotong
University, Beijing, 100044, China
E-mail: li.weili@yeah.net
Wu Zhigang, School of Electrical Engineering, Beijing Jiaotong
University, Beijing, 100044, China
Yang Shaohua, Jiang Su Weiteli Motor Limited By Share
ltd, Taizhou 225318, China