Performance of Power-Line-Signaling Based Detection Algorithms for Islanding Protection of Distributed Generators in Interharmonic Polluted Systems

Abstract

Recently, a new islanding detection scheme based on power electronic signaling technology has been proposed in the literature. By broadcasting a signal on the distribution feeders from the substation to the down-stream DGs, the absence of the signal at the DG site will be a sign of islanding. The scheme is more reliable than regular local detection techniques while it costs much less than transfer trip schemes. As the checking of the signal continuity is done via signal detectors, performance analysis of implemented detection algorithms is one of the main concerns. Since, the scheme relies on distortion broadcasting, our purpose is to answer the first question arises i.e., `` Is it a reliable scheme for DGs located at industrial areas that are rich in harmonics and interharmonics? ". Results show that for spectral based detection algorithms, more selective thresholds must be set in case of excessive interharmonic pollutions.

Grid reconnection detection for synchronous distributed generators in stand-alone operation

“…For the parameters influencing the frequency of LEM, further evaluation was performed according to Equation (9). Figure 13 and Tables II-IV include the results.…”

“…Although grid reconnection detection could be performed via breaker status communication (transfer trip) or power line carrier‐based methods, introduced in , these methods are considered to be expensive for DGs on a utility circuit. This is mainly for expensive signal generators used in power line carrier‐based methods of and similarly for the cost of the transfer trip scheme and its communication channel . Moreover, schemes based on breaker status communication must adapt to topology changes in the system, and the adaptation results in poor reliability of the system while it requires many communication links .…”

“…The inverse issue, detection of reconnection to the main grid and the proper control mode activation, is introduced in . Although grid reconnection detection could be performed via breaker status communication (transfer trip) or power line carrier‐based methods, introduced in , these methods are considered to be expensive for DGs on a utility circuit. This is mainly for expensive signal generators used in power line carrier‐based methods of and similarly for the cost of the transfer trip scheme and its communication channel .…”