Secondary concentrator design of an updated space solar power satellite with a spherical concentrator

Abstract

The Space Solar Power Satellite (SSPS) is a promising project to solve the energy crisis on earth. In this paper, a secondary concentrator design of an updated SSPS-OMEGA concept is proposed aiming at the problems existing in original SSPS-OMEGA concept, such as high power transmission through power brush, thermal management of the photovoltaic (PV) cell arrays and special requirements for the concentrator film brought by the inside placed transmitting antenna. Firstly, the updated concept with a secondary concentrator, a disc PV cell arrays and outside placed transmitting antenna is illustrated and main parts of it are described. Secondly, a design methodology of the secondary concentrator is presented. The characteristics of spherical concentrator are simply described. The generatrix geometry of the secondary concentrator is described using Bézier curve, and the performances of optics and energy density distribution on PV cell arrays are evaluated using the Monte Carlo Ray Tracing method. After that, a mathematical optimization model is established and the Particle Swarm optimization is used to obtain better configuration of secondary concentrator, solar energy collection performance and energy density distribution on PV cell arrays. Finally, the optimal generatrix geometry of secondary concentrator and energy density distribution under different orders of Bézier curve are investigated, the result shows that the effective solar energy collection and solar energy collection can be up to 81.14% and 87.06% respectively when the order of Bézier curve is 5. Moreover, a further energy density distribution optimization is conducted and the relative non-uniformity index of 0.4 is realized.