Reliable placement of synchronized phasor measurements on network branches

This paper presents a practical approach to assign synchronized phasor measurements to appropriate network branches in order to observe the entire system. Earlier studies assume that phasor measurement units are capable of monitoring all branch currents incident to the studied substation. This paper relaxes this unrealistic assumption and considers more practical phasor measurement units which can monitor individual lines or transformers. While the paper considers an initially blank measurement set and proposes a method to populate the system branches with phasor measurement units, it can be used to simply extend observability of unobservable systems equipped with conventional metering. Furthermore, the objective of the placement problem is expanded to incorporate the reliability against loss of phasor measurement units or unexpected outage of lines and transformers. Hence, the resulting method provides a comprehensive measurement configuration which not only makes the system observable but maintains observability during such contingencies. Numerical results of applying this method to IEEE test systems are given.