Evolução diferencial binária aplicada na otimização da margem de estabilidade de tensão via seleção de conjuntos de controles corretivos

Abstract

The electric power system must supply energy with quality, security, and reliability. However, due to environmental or economic reasons, the system may operate close to its critical limits due to increasing demand. Under these circumstances, voltage instability problems may occur because of disturbances, and it can even cause a blackout. Thus, the security assessment of the electrical system has gained visibility and becoming an important matter. Over the years, several studies have been carried out to identify and control voltage instability problems, and the voltage stability margin is a parameter used to identify these problems, which can be calculated through the continuous power flow. Besides that, to prevent or correct these problems, preventive or corrective controls may be used, such as capacitors. Given this, this work develops a methodology to obtain a list of capacitors set to maximize the voltage stability margin considering a set of disturbances. This methodology aims to mitigate the criticality of a set of contingencies using two techniques, the first to find the stability parameter and the second to optimize it. The system stability parameter, voltage stability margin, is calculated using the continuation power flow, and the optimization of this parameter is done using the binary differential evolution to select the necessary set of controls. The proposed method provides feasible results to maximize the voltage stability margin and provides the system operator with important information about the set of controls that can be used, enhancing the operation of the power system. Besides, the proposed method was parallelized, and as a result, the parallelization execution was considerably faster than the serial one.