Operational Reliability Assessment And Software Development Of Power System

Since the beginning of twenty-first century, with the development of economy and the progress of science and technology, people’s demand for electric power also further expansion. In order to cope with the increasingly high demand, grid scale is continually expanding and structure is more complex, the numbers of elements contained in the grid are surge, degree of interconnection between regions is also rising, the importance of power system reliability is self-evident. There are many factors affecting the reliability of power grids, such as weather conditions, geographical environment, load changes, lack of active power and reactive power, the operation mode of power grid etc.The following is the main content of this paper.(1) Research on the dynamic failure probability of power system components. The problem is how to evaluate the probability of failure, from the traditional static fault probability to the real-time dynamic fault probability. Focus on line outage probability model that based on the line flow, and proposes an analytical evaluation method of component failure probability.(2) Study on operation reliability, it relates to the short-term load forecasting. This paper studied the method of short-term load forecasting based on the neural network load forecasting, in the original basis, considering the effect of climatic factors on the prediction value. Taking a certain city as an example, take the daily maximum temperature and the minimum temperature as eigenvectors to make short-term load forecast.(3) To evaluate the reliability of power system from the reactive power angle. Reactive power plays a significant role in power system operation and voltage management. Reactive power plays different rules in power system operation compared with active power and should be paid attention in reliability evaluation. It is not efficient to transfer reactive power over a long distance because of reactive power losses in transmission lines. Reactive power shortage and the associated voltage violations due to the failures of reactive power sources have been considered in the studies.(4) Based on the actual power grid for example, rapid judgment of the grid islanding. The graph theory of graph connectivity judgment is applied to the power grid structure judgment. Accelerated judgment time and saved the operation process.(5) Calculation and Analysis on the index of power grid operation reliability. Through the simulation of fault line and fault generator to determine the weak links of power grid. On the basis of the above study, carries on the analysis to the fault state of all possible. This process involves power flow calculation、to determine whether the transmission line overloads estimation of power network whether islanding or not、load shedding calculation or reactive power compensation process etc.(6) Taking the operation reliability evaluation process as software. In this paper, the operation reliability of power grid is analyzed, and then use the Visual Basic and Access software as the platform, compiled a set of power system operation reliability evaluation software. Using Visual Basic software called MATLAB operational procedures, and the MATLAB program for the calculation results are displayed in the VB window interface, it is as the man-machine interface; to manage large amount of data from calculation by Access software; finally, designed to power grid reliability evaluation software.