Proposed design of an optimal controller to maximise the efficiency of flat plate solar collector

Abstract

In a solar water heating system, a closed loop control system plays a vital role in maximizing the efficiency of the solar collector. In this thesis, this type of controller is considered. Water is pumped through the collector by means of a motor pump, and the quantity of water to be pumped at a certain moment will be decided when the net power which is the thermal power less the parasitic pumping power is fed through a logic decision unit called an extremum seeking controller which provides an output signal that either increases or decreases average power that drives the pump and as such the quantity of water fed into the solar collector is dependent on the intensity of the solar radiation striking the collector`s absorber, the flow rate converted to equivalent frequency and the pumping power. The complete system that manipulates these variables and gives the desired output response is referred to as an optimal control system.

In a solar water heating system, a closed loop control system plays a vital role in maximizing the efficiency of the solar collector. In this thesis, this type of controller is considered. Water is pumped through the collector by means of a motor pump, and the quantity of water to be pumped at a certain moment will be decided when the net power which is the thermal power less the parasitic pumping power is fed through a logic decision unit called an extremum seeking controller which provides an output signal that either increases or decreases average power that drives the pump and as such the quantity of water fed into the solar collector is dependent on the intensity of the solar radiation striking the collector`s absorber, the flow rate converted to equivalent frequency and the pumping power. The complete system that manipulates these variables and gives the desired output response is referred to as an optimal control system.