A Cascade Proportional Integral Derivative Control for a Plate-Heat-Exchanger-Based Solar Absorption Cooling System

Automatic proportional integral derivative control techniques are applied in a single-stage solar absorption cooling system, showing 3.8 kW (similar to 1 ton) cooling capacity, with a coefficient of performance of 0.6 and -4.1 degrees C evaporator cooling temperature. It is built with plate heat exchangers as main components, using ammonia-water as the working mixture fluid and solar collectors as the main source of hot water. Control tuning was verified with a dynamical simulation model for a solution regarding mass flow stability and temperature control in the solar absorption cooling system. The controller improved steady thermodynamic state and time response. According to experimental cooling temperatures, the system could work in ranges of refrigeration or air-conditioning end-uses, whose operation makes this control technique an attractive option to be implemented in the solar absorption cooling system.

Automated summary

The study applied automatic proportional integral derivative control techniques to improve the performance of a solar absorption cooling system, enhancing the steady state and response speed, making it suitable for refrigeration and air conditioning applications.