Research On The Forecasting Track Of Power Grid Operation State Based On Risk Assessment

With the rapid development of national economy and productive forces, the size of power grid is gradually expanded. And the voltage level is also promoted. More and more large-scale renewable energies are accessing power grid. The power grid dispatching technology must be continuously improved to ensure the safe and stable operation of power grid. However, as the power grid becomes increasingly complicated and external environment is changeable, the difficulty and challenge of power grid dispatching are increased. Thus, based on current achievements of smart grid technology support system, the ability of perceiving power grid operation state and predicting power grid risk in the future must be improved right now. These essential measures aim to provide data support for power grid smart dispatching research and provide effectively scientific assistance for dispatching workers to control power grid operation.Considering the influence of external environment and uncertainty of power grid operation, the forecasting track of power grid operation state based on risk assessment is researched. According to the principle of SMART and aiming at assessment of power grid operation risk, the index of power grid risk is refined as first index, four key indexes are proposed as secondary indexes to reflect power grid operation state. Based on that, the end indexes are further researched. In this way, the index system of power grid operation track based on risk assessment is established. Based on this, power grid risk is quantitatively evaluated to predict the track of power grid risk.In the index system, the data of any index is provided by cascading failure evolution model. According to the diversity and rationality and consistency of indexes values, the index values of all serious fault scenarios can be calculated. Meanwhile, considering the fault probability of each fault scenario provided by equipment fault probability model based on subjective Bayesian, for one index, the risk value of index in each serious fault scenario is calculated by using fuzzy inference, which applies fuzzy evaluation based on index values and fault probabilities of all serious fault scenarios. Then the risk value of index can be calculated by using fuzzy C-means clustering. In the same way, the risk values of all the indexes can be obtained. According to the weights analyzed by analytic hierarchy process(AHP), the risk degree of overall power grid can be obtained. So the risk of power grid in the future can be quantified and the track of power grid operation can be predicted by the risk degree.Finally, one coastal provincial grid is simulated by MATLAB. The results show that the characterization method of the forecasting track of power grid operation state based on risk assessment is correct and reasonable. Meanwhile, the method can combine with power grid ground state real-time operation to become a characterization method of the forecasting track of power grid operation state based on situation awareness. It can predict the security situation of power grid in the future objectively and effectively to assist dispatching control strategy.