Auto-optimization control of hybrid ecological refrigeration system

International Conference on the Sustainable Energy and Environmental Development

生态环境科学

Duda, R.^1 ; Cyklis, P.^1

Cracow University of Technology, Institute of Thermal and Process Engineering, Cracow, Poland^1

关键词: Energy consumption and cost;    External conditions;    Optimization control;    Optimization problems;    Process disturbances;    Programmable logic controllers (PLC);    Refrigeration system;    Sorption refrigeration;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/214/1/012007/pdf
DOI  :  10.1088/1755-1315/214/1/012007

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

The optimization problem of the two-stage hybrid compression-sorption refrigeration control system is presented. The idea is an eco-friendly energy conversion, powered by the waste heat or renewable energy. Eco-friendly means that using only natural energy carriers H2O and CO2 are used. The goal of the optimization is maximization of the renewable energy usage and increasing of the system COP, by minimization of the power consumption. The optimization problem is complex due to the large amount of control parameters. In the programmable logic controller (PLC) a set of functions is implemented. As a result the consumption of all kinds of energy supplied to the system in the different modes of operation may be calculated online. This can be applied as the control function for optimal usage of the available heat sources, while maintaining the temperature in the refrigerator compartment at desired level. Similar method of process optimization in the last years was introduced for the energy consumption and cost reduction in the operation of industrial and home appliances. In larger industrial scale more energy savings are possible using this approach. The work of entire refrigeration system can be based on this idea, reducing the consumption of electricity used to drive compressors, fans and pumps. Each step of the optimization has to consider process disturbances and external condition changes, therefore the system control becomes a complex issue. Number of optimization methods may be found in the literature. However in this case the application of the simple adjustment method based on the selected variables, control parameters, with dependence between them was proposed. This approach has been called auto or self-optimization. In this method the nominal value is set, but some possibility of losses are accepted. This type of optimization is used with single or several linear variables depending on the measured value in the system, which are usually controlled by PI or PID controllers.