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Short-term power flow analysis has a significant influence on day-ahead generation schedule. This paper proposes a time series model and prediction error distribution model of wind power output. With the consideration of wind speed and wind power output forecast error’s correlation, the probabilistic distributions of transmission line flows during tomorrow’s 96 time intervals are obtained using cumulants combined Gram-Charlier expansion method. The probability density function and cumulative distribution function of transmission lines on each time interval could provide scheduling planners with more accurate and comprehensive information. Simulation in IEEE 39-bus system demonstrates effectiveness of the proposed model and algorithm.

The inherent variability and uncertainty of intermittent generations bring great challenges both to the safe operation of power grid. In this paper, we present a novel stochastic security constraint unit commitment (SSCUC) model that can take into account multi-objective and various probability constraints, especially effective in treating transmission constraint. The model focus on the difficulties in controlling of probabilistic power flow, introduces the Gram-Charlier series and cumulant to analyze the stochastic characteristic in the spatial dimension, so as to describe the stochastic factors in unit commitment problem with quantitative analysis means. On this basis, the model will be converted to a deterministic mixed integer programming problem in certain confidence level. The model is illustrated by IEEE 39-bus test system. Numerical results show that the proposed method is efficient and effective for dealing with multi-energy coordinative optimization in power system with intermittent sources.

The intraday security check is the core application in the dispatching control system. The existing security check calculation only uses the dispatch center's local model and data as the functional margin. This paper introduces the design of all-grid intraday joint security check system based on cloud computing and its implementation. To reduce the effect of subarea bad data on the all-grid security check, a new power flow algorithm basing on comparison and adjustment with inter-provincial tie-line plan is presented. And the numerical example illustrated the effectiveness and feasibility of the proposed method.

By the soil column experiments, the concentration of the pesticide’s solute in the outlet flowing were derived. The model parameters are determined using Kinetic model of two-site absorption-desorption model through experimental results and the MATLAB program developed by the authors. Based on these, the trends of pesticide’s solute transport at different time and depth in the soil column was estimated. This study suggests that Kinetic model of two-site absorption-desorption model can be used as a useful approach to better quantifying environmental fate of pesticide.