Compressed air control strategies for efficient pneumatic systems

Abstract

Over the past few decades, manufacturing companies throughout the industrial sector have become increasingly aware of their impact on global energy use due to the wide range of equipment utilised in their processes. A substantial portion of this energy use has been further attributed to a certain utility which is utilised across the industrial sector: compressed air. Although this utility provides various benefits with its use, compressed air systems are also inherently inefficient due to energy losses during the generation and distribution of compressed air. Thus, in order to achieve various global targets on energy use within the industrial sector, organisations throughout this sector have had to invest in the development of innovative technologies which aim to improve the energy efficiency of all their systems, including compressed air systems. As such, various control strategies have been developed in literature, a portion of which focus specifically on the demand side of compressed air systems. Furthermore, some market options have also been produced over the past few years which offer control over these systems. However, none of these options are intended to reduce the energy consumption of industrial pneumatic systems operating with faults present. Furthermore, the importance of maintaining the system’s productivity is often overlooked in current literature on the demand side control of these systems. Therefore, a control strategy which utilised system parameters to reduce the energy consumption of industrial pneumatic systems operating with faults present, whilst also maintaining the system’s productivity was investigated in this research project. The investigated control strategy involved the combination of pressure and flowrate regulation to achieve the aforementioned objectives. A multi-criteria optimisation method based on a Rule-Based system and the Weighted Sum Model was also developed to identify the optimal control parameters for different system requirements. Through this approach, the increase in energy consumption caused by leakages sized at 12 to 13% of the system’s total consumption were completely eliminated. As the leakage size increased to 30%, the control strategy was still 40% effective. Additionally, the system’s productivity was completely restored in each case. Furthermore, different control solutions for varying system requirements were also developed to mitigate the effects of a pressure drop in the system.