Research On Automatic Black Start Scheme Formation System

In recent years, several large-scale blackouts occurred around the world. After the blackout of the whole system, it is very trivial, complicated and time-consuming to restore power supply. Therefore, black-start study is about the issue how to restore the system safely and quickly after the large-scale blackout.At present, black-start schemes of the domestic grid corporations are manually drawn up, which can't reflect the new situation of system and is formed inefficiently. Therefore, we need a convenient and user-friendly black-start generation system which can not only reflect the new situation of system but also greatly reduce the labor intensity.Aiming at the above problems, in this thesis, we analyze the law of feasible black-start scheme, sum up the corresponding rules, design a search algorithm to find the initial black-start scheme and develop the corresponding automatic formation system of black-start path. The content and achievements of this thesis are presented as follows:1. An improved and rule-based depth-first search algorithm is proposed. Through the complete search of the feasible path in power system, several initial black start schemes are formed. Compared with other methods, the proposed algorithm has three advantages: (1) using the complete forward search terminated condition; (2) using the complete treatment measures of child nodes; (3) taking the priority of the load into account, to ensure that the path passes through important loads as many as possible.2. An automatic black start scheme formation system is developed, which includes graphical module, algorithm modules, and database module. Graphics module is made based on secondary development of VG plug-ins, which can connect the graphs and database, and achieves the automatic data annotation, the flexible construction of system diagram and forming the path by the manual points. Algorithm module includes the formation of initial path, self-excitation calculation, calculation of normal frequency overvoltage, operation overvoltage calculations and stability calculations and checking calculation of all paths, the feasibility judgment of the scheme, and ordering the paths according to their effectiveness . Database module is developed based on Oracle database, including data tables of all network equipment, and the tables relating to paths. Example system proves the effectiveness and correctness of the developed system.