Optimum allocation of power quality monitors in electric power systems — A case study

The Brazilian Electrical Transmission and Distribution Systems are regulated by codes called Distribution Procedures (PRODIST) and Basic Network Procedures (PROREDE), respectively. These procedures establish, among other things, performance indicators related to Power Quality - PQ and limiting values, with the aim of permitting penalties and inducing corrective actions in the Electrical Systems (ES), in transmission as well as distribution. To monitor these indicators and reference values, it is necessary to implant a system that monitors the PQ, a Power Quality Monitoring System (PQMS). The present study introduces a deterministic method (linear binary problem solved with the Branch and Bound method) which determines the quantity and the location of the power system monitors in order to guarantee that the monitoring system has a minimal cost (optimum allocation of monitors) and that the ES is totally observable, that is, the current of all the lines and the voltages of all the buses (state variables of the ES) are measured and/or estimated.