Operation optimization of a looped natural gas pipeline network based on dynamic programming and the golden section method

At present, China's natural gas trunk pipelines have been connected with each other to form a large-scale complex natural gas pipeline network of ring by ring. With the increase of gas-driven compressor sets in each compressor station, the steady-state operation optimization of the pipeline network is now a technical problem. In this regard, the effect of looped structure and dendritic structure in the pipeline network on the distribution of pipeline flow rate and the effect of the gas consumption rate of gas-driven compressors on the flow rate inside the pipeline were investigated. According to the segmentation idea of the pipeline network model, the golden section algorithm and the dynamic programming algorithm were integrated to form an improved hybrid algorithm of dynamic programming and golden section. The following calculation results were obtained with one certain looped pipeline network in the area of North China as the example. First, different form the single-line pipeline model, the mathematical model of pipeline network operation optimization had additional variables, e.g., the flow rate inside the pipeline and the gas consumption rate of gas-driven compressor, which increase the solution difficulty of the pipeline network model further. Second, the hybrid algorithm can effectively solve the mathematical model of steady-state operation optimization of looped and dendritic small pipeline networks with gas- and electric-drive compressor sets. Third, the optimization scheme of hybrid algorithm could increase the outlet pressure of the compressor station, enhanced the operation efficiency of the compressor set, and reduced system power and energy consumption while increasing the stock of pipeline network and providing the extra emergency resources of a pipeline network.