Research On Building A Concise Index For Security Assessment Of Power Grid Operation

As the basic content in power system security evaluation, reasonable and effective evaluation index can evaluate the complex power system accurately and fast, and it can be a basis for the grid security emergency plan and implement power grid dispatching work to guarantee the power system in a safe and stable operation for a long time. The existing power grid security evaluation index system is given priority to with tree diffusion model, which makes every effort to cover all the quantity of state grid operating, leading to the index system too large. Scheduling staff are often submerged by a large amount of data. It is difficult to find intuitive and effective information, and unable to accurately obtain the grid security margin, and then failed to take corresponding control measures.In this paper, according to the above problem, dominated by the dispatcher thinking mode, from the power grid operating balance which is a major task of power system, using a different way from traditional security evaluation index system of tree spread way, we put forward a concise power grid security level indicators from a macro perspective-reserve assessment index with power grid operation security constraints taken into account. Index sets security operation constraints of power grid to reserve level, so as to realize the organic integration of each single grid security assessment. It is a kind of power grid evaluation index which can reflect the future change trend indicators for a period of time, so as to represent the true state of the grid operating comprehensively and objectively, and enhance understanding of power grid operation state. Then it can work for automatic analysis of intelligent scheduling and provide reliable basis for controlling technology.Filter the theory results of overload safety, angle stability, voltage stability, frequency stability every side of power system security analysis; finish the security operation constraints to the generators output constraints. Through the research, make clear that the power generations as the object, to meet all kinds of safety constraints to solve the maximum value of reserve level, and then establish the mathematical model of optimization calculation. To avoid uneven system trends affect measure results, on the basis of the overall index model, local reserve level are proposed. Two kinds of calculation method for local index are designed. In view of the reserve and load distribution problems, the concept of time scales of load growth is introduced in the above index calculation model, reserve level index model considering the load growth is established. Finally, through the province network index calculation proves the practicability of the indicators. And through the province 24 hours local network system evaluation, the paper analyzes the relationship between the local index and the overall index. At last, by 24 hours reserve level index curve of IEEE 14 node, this paper discusses the changes of the reserve level index and its significance after considering the load growth.The concise evaluation index proposed in this paper are looking forward to provide practical reference value for the power grid safety evaluation work.