Estratégias de Controle para Melhorar a Produção de Exergia de um Campo Solar

Abstract

The operation of solar collectors for the harvesting of solar thermal energy is subject to intermittencies, disturbances and delays and requires the use of automatic control techniques to mitigate these effects. The present work investigates the usage of strategies based on classical control for a collector where both the flow rate of the heat transfer fluid and the partial defocusing of the mirrors can be manipulated. The performance of the control strategies is evaluated using an exergy production analysis, which, unlike an energy analysis, provides information on the temperature level and the thermodynamic losses arising from the irreversibilities of the process. The results show that the generalized split-range control is the most favourable strategy for operating the system, with an increase of 29.71% in the exergy produced when compared to the more conventional technique, in the evaluated scenario.