Energy optimisation of pneumatic actuator systems in manufacturing

Compressed air systems account for a significant proportion of industrial energy usage in the European Union and the United States. Improving the energy efficiency of final air consumers is an essential aspect of overall system optimisation. This paper investigates and compares the minimisation of air consumption in linear pneumatic actuator systems using two approaches: dual pressures and the utilisation of expansion energy in compressed air. In order to simplify the implementation of energy saving circuits for industrial end-users, a software program has been developed based on a combination of genetic algorithms and dynamic simulations. The developed program, described in this paper, automates the selection process of optimal design parameters and control input variables for pneumatic cylinders. The robustness of the optimisation software has been experimentally validated. The results from a vertical lifting application case study indicate that the proposed optimisation approaches can reduce compressed air usage by up to 29% per cycle, whilst simultaneously satisfying other common automation design objectives or constraints. The paper concludes with a discussion on methods to increase the application of such energy efficiency measures in pneumatic production machinery.