A dynamic security region construction method and its existence proof for gaseous system

Load fluctuation in the gas system typically causes the change of node pressures and pipeline flow rates, which may further lead to energy shortages or even security incidents. In order to accurately evaluate the gas supply security, a Gas Dynamic Security Region (GDSR) concept along with its construction method is proposed in this study. Firstly, the definition of GDSR is given considering both the dynamic characteristics and security constraints of the gas system. Then, a critical point sampling method based on the load increase direction is designed, where the uniform distribution of critical points on the Gas Dynamic Security Region Boundary (GDSRB) is ensured by deploying the multi-dimensional sphere sampling technique. Next, a piecewise fitting method based on the neighborhood least square technique is employed to precisely fit the GDSRB. In order to provide a rigorous mathematical foundation for its practical application, the existence of the GDSR is strictly proved based on the critical point existence theorem and the boundary closure theorem. The following experimental results conducted on a typical gas system verify the effectiveness of the proposed GDSR construction method and illustrate that GDSR can ensure the energy supply security of the single or integrated system in the load response. In addition, the practicability of the GDSR is demonstrated by its implementation in an iron and steel plant in China which also indicates that the shape and position of the GDSR are closely related to the initial working conditions.