Development of a Solar Photovoltaic Magnetic Suspension System

Extra low-power suspension in gravitational field is achieved by a magnetic suspension system whose power source is solely solar photovoltaics. Presently, solar photovoltaic cells become more efficient and cost-saving year by year. In this study, solar photovoltaic generation technique is combined with the zero-power magnetic suspension. The zero-power control achieves the steady state in which the attractive force produced by the permanent magnets balances the weight of the floator and the control current converges to zero. In this system, the power necessary for generating the suspension forceis very small. However, the peripheral devices including sensors and a controller need power for operation. The power consumed in the peripheral devices becomes dominant in the total power in the steady state. In this work, dedicated power-saving peripheral devices are newlyfabricated. The average power consumed in the electromagnet is 20[mW] to suspend a 90-glammass, while the power consumed in the peripheral devices is 24[mW]. The photovoltaic cells used in the apparatus has a maximum power capacity of about 2[W] in the summer sunlightof 120[kLx]. The system achieves stable suspension even under the illuminance of a fluorescent lamp of 7[kLx].