Contents I. Introduction
The electric dynamic suspension (EDS) maglev train, as a repulsive force system, is mechanically self-stabilizing and has a large suspension air gap (above 100 mm) [1]–[4]. Therefore, the EDS have more development advantages under the conditions of high-speed and ultrahigh speed operation. It can be used as one of the ideal vehicles for high-speed and ultrahigh-speed passenger transportation in the 21st century [5]–[7]. Since the concept of electric levitation was proposed by American scientists JRPowell and GTdanby in 1966 [8], the countries such as Japan, the United States, South Korea, and China have begun to develop electrodynamic maglev technology [9]–[13]. The representative electric maglev train of MLX01 type has created the maximum ground test speed of 603 km/h [7]. The top view and cross-sectional diagram of superconducting electrodynamic maglev train of MLX01 type is shown in Fig. 1. The propulsion coil on the guide rail and the superconducting (SC) coils on both sides of the bogie form a linear synchronous motor to realize the driving function of the train, while the electromagnetic interaction between SC and levitation/guidance (LG) coils realizes the levitation /guidance function of the train. Since the passive electromagnetic damping between SC coil and LG coil is very small during EDS train operation, and the train is composed of light vehicle body and relatively heavy bogie structure, it is of great significance to increase the electromagnetic damping during train operation and improve the stability of the train.
Sketch map of superconducting electrodynamic maglev train. (a) (a) Upper view of superconducting electrodynamic maglev train. (b) Cross section of superconducting electrodynamic maglev train (1. Propulsion coil; 2. LG coil; 3. Track beam; 4.SC coil; 5.Wheel path).
