Optimal control of a variable speed drive compressor for energy efficiency of a compressed natural gas station

Energy consumption by the compressor in a compressed natural gas station constitutes a major part of the operating costs of the station. The gas compression and vehicle filling processes can benefit from an optimized control approach to the operation of the compressor especially when variable speed drives are considered. The variable speed drive allows for continuous selection of operation parameters with consideration for various cost factors resulting in an optimally operating gas flow process that saves time, energy and energy costs. The optimal control problem has a nonlinear objective function with linear and nonlinear constraints, and is solved with an evolutionary hybrid algorithm solver, achieving 30% reduction in energy consumption, 76% reduction in energy cost and a 17.5 seconds average reduction in vehicle filling times.