The present paper focuses on the design, realization and validation of the prototype of an innovative relay, named SmartID, for islanding detection in LV distribution systems. The SmartID adopts a patent-pending detection method: it uses local measurements to estimate the parameters of a linear model of the distribution system, which can be used to distinguish grid-connected from islanded operation. The hardware of the SmartID prototype is composed of a voltage transducer, some conditioning stages, a commercial μcontroller and an output stage. The software implements the A/D conversion of the measurements, the phasors evaluation by Kalman Filters, the model parameters estimation by a constrained recursive least-squares algorithm, and the detection criteria. The validation of the SmartID is performed on a test site in a smart grid located in Isernia (Molise, Italy). Experimental results show the good performance of the SmartID in the detection of both grid-connected and islanded operation; transitions from one condition to the other is only partially analyzed, due to the limitations introduced by the use of a commercial DG. The anti-islanding relay is the result of a joint research project among the University of Cassino and Southern Lazio, Ambra Energy System S.r.l. and Enel Distribuzione S.p.a.
A smart device for islanding detection in distribution system operation
DI FAZIO, ANNA RITA;FUSCO, Giuseppe;RUSSO, Mario;VALERI, Sara;
2015-01-01
Abstract
The present paper focuses on the design, realization and validation of the prototype of an innovative relay, named SmartID, for islanding detection in LV distribution systems. The SmartID adopts a patent-pending detection method: it uses local measurements to estimate the parameters of a linear model of the distribution system, which can be used to distinguish grid-connected from islanded operation. The hardware of the SmartID prototype is composed of a voltage transducer, some conditioning stages, a commercial μcontroller and an output stage. The software implements the A/D conversion of the measurements, the phasors evaluation by Kalman Filters, the model parameters estimation by a constrained recursive least-squares algorithm, and the detection criteria. The validation of the SmartID is performed on a test site in a smart grid located in Isernia (Molise, Italy). Experimental results show the good performance of the SmartID in the detection of both grid-connected and islanded operation; transitions from one condition to the other is only partially analyzed, due to the limitations introduced by the use of a commercial DG. The anti-islanding relay is the result of a joint research project among the University of Cassino and Southern Lazio, Ambra Energy System S.r.l. and Enel Distribuzione S.p.a.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
