Decentralized Voltage Control Using Fast Community Detection Algorithm and Eigen Decomposition

Voltage and Frequency control are the two fundamental control problems in power systems. Unlike frequency control, voltage control is complicated by the fact that reactive power cannot travel far distances from its source. Due to this distributed nature of reactive power, voltage control is usually performed in a decentralized manner. This paper presents an optimal decentralized secondary voltage control. First, a large system is decomposed into small subsystems called voltage control areas (VCAs) using the Fast Community Detection algorithm. Each VCA is self-sufficient in satisfying its reactive power demand. Second, a load bus, called pilot bus, is selected in each VCA as a representative of the voltage profile of the whole area. Third, Eigen Value Decomposition of Fast Decoupled Load Flow (FDLF) Jacobian is used to optimally control the voltages of these pilot buses. The presented approach is tested on a 39-Bus power system.