الفهرس | Only 14 pages are availabe for public view |
Abstract lywheel power systems are now seen as a technology that can be used in various applications, including low-earth space satellite orbits, pulse transmission for hybrid electric vehicles and many other applications. In consideration of the energy storage feature, a flywheel device has great advantages over chemical batteries for Low Earth Orbit (LEO) satellites: lifespan, density of power, short charge time, wide operational temperature band, and deep depth of discharge. Flywheel systems have significant advantages over chemical batteries also it can be used to control the spacecraft attitude. The combination of energy and attitude control is a reasonable solution to improve space missions for satellites. Double counter-rotating flywheels mounted on an air table are introduced in this thesis to execute the control system of combined power and single axis attitude control. The system control technique of integrated power and attitude control could be implemented based either on a speed control mode or on a torque control mode. The control algorithm’s method is field orientation control. This method offers the flywheel motor / generator with precise and high bandwidth torque control by controlling rotor reference frame currents that are dc in steady-state. The Permanent magnet synchronous motor/generator is controlled by the direction of the field. The current rotational frame of the d-axis is ordered to zero and the q-axis current component changes to maintain the required dc bus level and commanded attitude angle. MATLAB Simulink was used to model the combined power and single-axis attitude control system using two similar flywheels. Furthermore, different cases and different modes of operation are presented which showed that flywheels behavior changed according to different operation. |