Active control of natural gas pipeline system based on Box-Jenkins method

• Developed a transient model for natural gas pipeline system. • Calibrated the model coefficients using operational data. • Established a state inversion control algorithm and a Linear Quadratic Regulator control algorithm. • Three case studies of a pipeline system demonstrate the practicality of the active control algorithms. As the integrated energy network continues to develop, uncertainties in both the upstream and downstream components of the natural gas system have increased significantly. This has led to higher demands on the intelligence of natural gas pipeline system, which must be capable of independently analyzing market fluctuations and proactively adjusting operational plans. However, the non-convexity and strong nonlinearity of the partial differential equations (PDEs) governing transient natural gas flow pose challenges. Traditional methods are inadequate for meeting the fast control requirements of modern intelligent regulation. This paper proposes an active control method for natural gas pipeline systems (NGPS), including state inversion control and the linear quadratic regulator (LQR) control algorithm, which is established using the Box-Jenkins approach to enable rapid control under transient conditions. Several case studies conducted on a natural gas pipeline system demonstrate the effectiveness of the proposed method. The results show that transient operation schemes for the compressor can be formulated under fluctuating outlet flow conditions, effectively maintaining the delivery pressure close to the contractual pressure. The control error is less than 0.5%, fully meeting the actual field requirements, and compared to constant-pressure delivery, it reduces energy consumption by 8,342 kWh per day. By strictly adhering to the characteristic equations of transient natural gas flow, the proposed method avoids the need to solve large-scale optimization problems. Additionally, it contributes to energy-saving and emission reduction objectives in natural gas pipeline operations, providing technical support for the intelligent regulation of future natural gas pipeline system.