OPTIMIZATION OF ELECTRIC MOTOR-DRIVETRAIN SYSTEMS FOR HELIOSTATS IN CONCENTRATED SOLAR POWER PLANTS

Abstract

The objective of the proposed research is to present a design method to simultaneously optimize the electric motor and drivetrain system for driving heliostats in concentrated solar power (CSP) plants. The ultimate objective of this dissertation is to develop a framework and a prototype for an optimized induction machine explicitly designed for heliostat applications that can be integrated with the speed reducer and the other electric drive components. The integrated system aims to reduce the overall cost of CSP plants to increase its share among renewable energy sources. To start with, the torque capabilities of the system are specified by identifying the moment of inertia and the maximum wind load of a benchmark heliostat, as well as properly defining the extreme motion profile. Secondly, the optimal gear ratio of the drivetrain system can be determined based on inertia matching theory, which can be used to select an off-the-shelf drivetrain with a gear ratio close to the optimal value. Simultaneously, the maximum torque requirement of the induction motor and its axial length can be optimized using Maxwell’s stress tensor theorem. Finally, finite element analysis (FEA) results for the induction motor are used to manufacture a special induction machine dedicated to this application.