Abstract: A solar powered air vehicle that can stay aloft for indefinite periods of time. The vehicle employs photovoltaic solar cells for primary power and high speed counter-rotating flywheels for energy storage and steering of the vehicle. The flywheels are placed in the wing to reduce airfoil drag. A control law provides three-axis stabilized control of the vehicle by controlling propeller pitch to vary the speeds of the flywheels.

Abstract: A solar powered air vehicle that can stay aloft for indefinite periods of time. The vehicle employs photovoltaic solar cells for primary power and high speed counter-rotating flywheels for energy storage and steering of the vehicle. The flywheels are placed in the wing to reduce airfoil drag. A control law provides three-axis stabilized control of the vehicle by controlling propeller pitch to vary the speeds of the flywheels.

Abstract: In a solar electric supply system in which an electrical load is supplied with current produced by a solar array formed of multiple solar panels, each solar panel is individually selected and tested to ensure proper performance by varying the duty cycle of an associated variable transconductance device connected between such solar panel and the electrical load. The method determines the respective solar panel's open circuit voltage, its full-load current and obtains various output voltage and current values responsive to different duty cycles, whereby the maximum power point for the solar panel may be determined.