Supervision and c-Means clustering of PID controllers for a solar power plant

A hierarchical control strategy consisting on a supervisory switching of PID controllers, simpli ed using the c-Means clustering technique, is developed and applied to the distributed collector eld of a solar power plant. The main characteristic of this solar plant is that the primary energy source, the solar radiation, can not be manipulated. It varies throughout the day, causing changes in plant dynamics conducting to distinct main several operating points. To guarantee good performances in all operating points, a local PID controller is tuned to each operating point and a supervisory strategy is proposed and applied to switch among these controllers accordingly to the actual measured conditions. The experiments were carried out within the project "Innovative Training Horizons in Applied Solar Thermal and Chemical Technologies" (C. N.:ERBFMGECT950023) supported by the European Union Program "Training and Mobility of Researchers" and promoted by CIEMAT-IER. The authors would like to express their gratitude to the personnel of the Plataforma Solar de Almeria, in particular Pedro Balsa. The authors also acknowledge suggestions by the reviewers that have helped considerably in the improving of this paper. This work was partially supported by the Portuguese Ministry of Science and Technology (MCT), under program PRAXIS XXI. Address correspondence to CISUC Centro de Inform atica e Sistemas da Universidade de Coimbra Departamento de Engenharia Inform atica P olo II UC 3030 COIMBRA PORTUGAL Phone: +351 39 790000 Fax: +351 39 701266 Email: fjh, alberto, [email protected]