Levitation-guidance stabilization of superconducting maglev through LSM currents
This paper presents a modeling and simulation of a superconducting maglev vehicle with a levitation and guidance assist method we have proposed. The assist system stabilizes and assists the vehicle operation so that the vehicle does not need to depend on the mechanical wheels as much as possible at low speeds. By controlling the LSM armature currents, the auxiliary levitation and guidance forces are provided. The results show that the assist system produces appropriate levitation and guidance forces, establishing the reference levitation height and a sufficient guidance at low speeds even against the disturbance force of lateral wind.
Propulsion control of superconducting linear synchronous motor vehicle
The armature current of a superconducting Linear Synchronous Motor (LSM) for a maglev vehicle is controlled to produce a suitable propulsion force so that the vehicle follows the reference speed signal sent from a control station. Besides the power is supplied from some inverters to the LSM armature sections where the vehicle exists. This paper shows an exact mathematical modeling of the propulsion control system to treat the system analytically, which is used for designing controllers and performance computer simulations. The calculated results include the simulations when the vehicle goes through power feeder section borders and tunnels that have a large aerodynamic drag force with account taken of inverter failure.
Design of guidance system for superconducting maglev vehicle using propulsion coils
Superconducting magnetically levitated vehicles have guidance coils that produce vehicle guidance forces using a null flux coil connection. However, the resulting forces do not have sufficient damping forces to suppress lateral vibration of the vehicle. Even though the experimental system has some magnitude of damping, it is still unsatisfactory. Moreover, since the guidance forces are very weak at low speeds, the minimum levitating speed is limited. The paper proposes a guidance method using LSM armature coil currents. When the currents are decomposed into the dq frame variables so that the d‐axis is assigned to the field axis, the d‐axis component of the currents generates lateral forces. The lateral forces of the vehicle are formulated, and the guidance force coefficient is defined. In addition, the author presents a design formula for a guidance regulator system that employs a dynamic compensator using a feedback signal of lateral displacement. The calculated results show that the guidance regulator system works as intended. © 2001 Scripta Technica, Electr Eng Jpn, 137(2): 44–51, 2001