The MLX01 superconducting maglev vehicles have entered their seventh year of running tests on the Yamanashi Maglev Test Line (YMTL). In 2002, new types of guideway, ground coils and vehicles were introduced and test runs started to verify the characteristics of these new technologies. This paper reports on the current status of the vehicle-running tests and recent developments in the new technologies incorporated on the test line.

抄録全体を表示

New vehicles have been manufactured for the Yamanashi Maglev Test Line that aim at improving several characteristics based on the test results of existing train-sets. Since July 2002, we have been obtaining data from the test running of two new vehicles, the Mc5 leading car and the M4 long-size intermediate car. The Mc5 is a special leading car to test reductions in micro-pressure waves, and the M4 is a prototype commercial car with improved ride comfort. This paper describes the contents of technical developments to investigate aerodynamic characteristics, improve ride comfort and reduce cabin interior noise, for comparison with those of existing vehicles.

抄録全体を表示

Three types of sidewall, the panel, beam and directly-attached coil type, were adopted as guideway structures for the Yamanashi Maglev Test Line. We evaluated their merits and demerits and developed a new type guideway structure based on the results. Emphasis was placed on improving the efficiency of attaching the sidewalls onto the concrete roadbed as a means to reduce construction costs. We discussed the installation efficiency of several sidewall shapes from all aspects, and eventually adopted an inverted-T-shaped sidewall, fixed to the concrete roadbed by four supports. This paper reports the design of the support in detail, as it is a very important component of the new guideway structure.

抄録全体を表示

The superconducting magnetic levitation (maglev) system under development in Japan uses a linear synchronous motor (LSM) with armature coils on the ground. The power converter driving the LSM should be able to generate power of variable voltage and frequency according to the speed and thrust of the train. Therefore, we adopted a pulse width modulation (PWM) inverter on the Yamanashi Maglev Test Line. For power conversion the maglev system requires highly efficient large-scale PWM inverters. In addition, manufacturing costs had to be reduced, so we developed several control methods to enhance the output voltages of the inverter without changing its circuit configuration. This paper describes the characteristics and some results from experiments involving these control methods.

抄録全体を表示

For the magnetically levitated (Maglev) transport system that uses superconducting magnets (SCM), it was important to develop an onboard power source that does not require contact with the ground and minimizes emissions of environmental pollutants such as noise and exhaust gases. We studied the feasibility of a linear generator (LG) that is integrated into an existing SCM, improved the output, power factor and measuring system, and tested it on the Yamanashi Maglev Test Line. A linear generator installed on the left half of a bogie was able to supply 25 kW of power to a Maglev vehicle in the 400 km/h to 500 km/h speed range, there being a good correlation between the results of analysis and vehicle running test measurements. The linear generator system thus expected to be of practical use.

抄録全体を表示

To make the superconducting magnetically levitated (maglev) transport system more attractive, it has been important to enhance the ride comfort by controlling vehicle vibration. We have reduced maglev vehicle vibration by controlling only the secondary suspension between the car bodies and bogies. However, by doing so, it has been difficult to reduce vibration for the characteristic and relatively high frequencies of the primary suspension. Recently, we have directed our attention to primary suspension control, using power collection coils of the distributed-type linear generator system, which we are testing as an onboard power source. Because this type of vibration control can apply damping directly to the primary suspension, we consider it to be optimal for reducing vibrations at high frequencies. We have used maglev vehicle models that focus on lateral, vertical, rolling, and pitching motions to describe the effectiveness of reducing vibrations by using linear generator system damping force control in the primary suspension and linear quadratic (LQ) control of the actuators in the secondary suspension.

抄録全体を表示

The purpose of these studies was to reduce the mechanical heat load generated inside onboard superconducting (SC) coils. Fretting tests were performed at liquid-helium-cooled boundaries between the structural components of SC coils, the test results demonstrating that mechanical loss had occurred at the boundary between an epoxy-impregnated SC coil and coil fasteners. The correlation between SC coil vibration and increment of heat load in the eigen-mode of SC coil twisting was also investigated and discussed by performing vibration tests and dynamic harmonic analysis. The results suggested that frictional heat occurred in the areas subjected to the greatest degree of bending.

抄録全体を表示