Search

Real-time monitoring is a key tool for several automated features in distribution system. However, due to the limited number of real-time measurements, distribution system monitoring generally relies on load modeling procedures. This paper presents field results for a real-time monitoring tool that was implemented on a Brazilian distribution utility to provide load values for service restoration software. The implemented tool comprises two steps. The first step consists of preprocessing routines that provide the required information for a real-time load estimator that is executed in the second step. The field results provide evidence of the practical viability of the implemented real-time monitoring tool, demonstrating the tool overcomes some usual limitations of real-time load estimation procedures. More specifically, the implemented tool is able to handle multiple and different types of real-time measurements, treat real-time measurements on the feeder and not only in the head of the feeder, handle obviously bad data, and to satisfy the performance requirements on practically sized distribution systems. Besides proposing and confirming a real-time monitoring tool on a real distribution system, this paper shares valuable utility experience on providing new insights and the challenges faced for real-time monitoring projects. [ABSTRACT FROM PUBLISHER]

This paper proposes an optimization model to minimize the load curtailments necessary to restore the equilibrium of operating point with relaxation of restrictions. This model can be used for the operation planning of electrical power systems. The developed methodology minimizes the load cuts, limiting them to their importance and establishing different stages for them through the relaxation of the minimum limits of voltage and maximum limits of active power flows through the transformers. For instance, when an emergency occurs, if some operational limits are violated for a short period, fewer loads can be cut at a first stage than would be necessary if those violations would not be admitted. If the emergency does not cease, the remaining cuts necessary to recover the violations are made as a second stage of the strategy. On the other hand, if the contingency ceases, within this break, the system is recovered, and at this second stage, unnecessary cuts can be avoided, admitting only small breakings of operational restrictions. This methodology was tested at a system of 291 buses that is equivalent, in heavy load, to the electric network or the State of Parańa in Brazil. [ABSTRACT FROM AUTHOR]