The probabilistic load flow analysis of power system considering the fluctuation of smelting load

Currently, special power load represented by smelting load presents the characteristics of large capacity and high density in part of China power grid. The power fluctuation of smelting load has a great impact on power system security. The probabilistic load flow method can fully take into account the random fluctuation of these special load. Firstly, the probability distribution model is presented based on the probability density curve of the measured data of smelting load considering the power fluctuation characteristics. The Monte Carlo method is applied to the system probabilistic load flow calculation with smelting load, and the node probability distribution of voltage and the active power of branch are obtained. The variation characteristics of node voltage and branch power with system normal operation and branch outage contingency under the smelting load influence are analyzed. The results show that the fluctuating range of node voltage and branch power may be increased, and the over-limit probability of node voltage increase with the randomness fluctuation of smelting load. When the outage branch is near from the smelting load, the probabilistic distribution of the branch active power change. The method is applied to IEEE 30 node system for comparative analysis, which verifies the feasibility and effectiveness of it.