Estimating Energy Costs by Simulating Dependence between Turning Parameters

摘要

In general, manufacturing energy costs consist of an energy charge (total kWh × $/kWh) and a demand charge (peak kW x $/kW). Although researchers have thoroughly studied these charges, there is a potential to investigate the dependence between production parameters to compute production energy costs. These parameters have been assumed to be independent frequently in existing studies, but the dependence of production parameters can affect the peak kW and associated energy costs, suggesting a need to study the dependence of production parameters for manufacturing processes. This paper, therefore, examines a turning machine job shop model that considers two production parameters (processing times and processing amounts) and their dependence to estimate turning energy cost by simulating machine level power demand. By combining discrete event simulation and numerical simulation for power demand, we simulate various cases considering the dependence between two turning machine parameters. To model multiple dependence structure, we apply various copula models considering different marginal distributions. With 30 case studies, we show that by changing the manufacturing strategy to adjust the dependence of production parameters, peak demand and energy cost can be reduced by more than 22% and 6%, respectively.