Probabilistic Power Flow Based Renewable Energy Line Flow Sensitivity Analysis

The uncertainty of renewable energy sources (RESs) presents a challenge for power grid operation. To analyze the variability of RESs, a probabilistic power flow (PPF) method has been introduced. This method can be used to evaluate the uncertainty of RES power generation and its effects on system voltage and power flow. In this study, an analytical approach for RES with PPF method to calculate line flow sensitivity by RES uncertainty is proposed, which directly analyze uncertainty by probability distribution calculation. This paper also proposes a line flow sensitivity index by RES implement to effectively measure transmission hosting capacity. The index is based on the RES probability distribution function (PDF) and power transfer distribution factors (PTDF). Firstly, the PDFs of RES are calculated to measure the affect to line flow. Then, each PDF is transferred to the line flow distribution using the PTDF. Starting from the baseline flow, the final line flow distribution can be analyzed by calculating each RES PDF and this study used the central limit theorem method. The line flow sensitivity of an RES implementation was directly calculated using the PPF and verified through a PSS/E Monte Carlo simulation in the IEEE 39 bus system. The calculated index matched well with the Monte Carlo simulation results.