PMU-based online real-time linear power flow calculation method with minimizing probability errors

With large-scale access to renewable energy, long-distance transmission via hybrid AC-DC networks and frequent load fluctuations, measurement-based online power flow calculation needs to be adapted to the volatility and randomness of modern power systems, and the high accuracy and real-time performance are required for online power flow. However, the traditional power flow method suffers from long calculation times, the convergence difficulty and the inaccuracy caused by RTU asynchronous errors. Therefore, a PMU-based online accurate linear power flow method with minimizing the probability errors of power flow is proposed to improve the accuracy and real-time performance. This power flow method no longer bounds PQ, PV or V0 buses, and establishes a linear relationship between the voltage measurements and the current measurements. To address the problems of complicated PMU measurement errors and the high proportion of low-quality data, a 0–1 integer programming model is established to select a set of linear measurement equations for minimizing probability errors, and a complete method of PMU-based linear power flow calculation is proposed. Finally, the efficacy of the proposed linear power flow calculation method is verified on IEEE 39 bus system and a large-scale power grid in China.