태양광 집광시스템을 위한 비선형 Robust AFC 설계에 관한 연구

Abstract

There are many renewable energy sources such as solar heat, sunlight, wind power, tidal power, wave power and fuel cells. Even so, a lot of effort has focused on utilizing fuel cells, wind energy and solar photovoltaic energy. This study was performed about a solar lighting system based on optical fibers, which condenses sunlight at one place using a concave reflector and transfers it to a remote distance through optical fibers and then it can be used as lighting at the remote place. To directly use sunlight as a light source, first of all, an exact sun position tracking system must be equipped and the focus of the condensing system using reflectors must be exactly controlled. While the sun position tracking system and the sunlight condensing system are operating, they can often vibrate and result in causing non-linear disturbance. Thereby, a study on condensing disturbance compensators to remove such non-linear disturbance was conducted.

Specifically this paper tracked the astronomic sun position based on a PID controller in order to implement a strong system against various non-linear vibration disturbances and then suggests its excellent performance which can control focus exactly using reflectors at the tracked position. While this system itself can be satisfactory, it does not reflect impact vibration in and out of the system. Therefore, this paper designed a disturbance observer (DOB) with strong resistance against disturbance, which can remove various aperiodic disturbances occurring under natural conditions. This study performed simulations at various angles, investigated various disturbance removal algorithms such as IMP, MAFC, CDIDF with reference to unknown aperiodic disturbances, improved the performance of the basic PID controller, and then verified the response characteristics and control performance of the sunlight condensing control system with more stronger resistance against disturbance by using non-linear AFC(CDIDF) regarding aperiodic disturbance. As a result, it identified that a robust sunlight condensing control system designed against disturbance is available.