Dynamic Network Security Analysis And Countermeasures Of SINOPEC Tianjin Company

Nowadays large scale industrial enterprises usually have their own power system, and in order to make this kind of power system operating security and stable, most of them are connected to the local power system. Usually, the grid voltage is 10kV, 35kV, 110kV and so on. But with the synchronization of so many self-owned generators, the network are getting larger and more complex, these caused a lot of troubles to the system's safe and economic operationThis article is based on the power grid of the SINOPEC Tianjin Company, connected I, II and III stage together. The highest voltage is increased from 110kV to 220kV. External power load is now supplied by the enterprise power system. It not only strengthens the structure of the enterprise network, but also improves the economic efficiency of system operation. But after the network's integration, the system will face transient stability problems, including frequency problem and voltage problem. Therefore, this paper is based on this and analyzes the problem in detail.This article first introduces the main power grid of the integrated wiring briefly, and builds up the mathematical model of the SINOPEC Tianjin Company's grid. Second, it analyzes the power system after the interruption of the frequency dynamic characteristics by using power system simulation software(PSASP). Finally, the problem of voltage drop based on short-circuit fault and the starting or reaccelerating of induction motor,and busbar differential protection is analyzed. The results provide a reference for SINOPEC Tianjin Company power grid, and also for other petrochemicals, iron and steel smelting companies when analyzing the dynamic security characteristics of the grid.