Chuttchaval Jeraputra, Eddy C. Aelwizal, Prasad N. Enjeti, Sewan Choi ¡°An improved anti-islanding algorithm for utility interconnection of multiple distributed fuel cell powered generations¡±

**Abstract** : This paper presents an improved anti-islanding
aIgorithm for utility interconnection of multiple distributed fuel
cell powered generations (DFPGs). A cross-correlation method is
proposed and implemented in conjunction with the antiislanding
algorithm developed in the previous work [I]. While
the power control algorithm continuously perturbs (*so/,) the
reactive power supplied by the DFPG, the proposed algorithm
calculates the cross-correlation index of a rate of change of the
frequency deviation with respect to (f5%) the reactive power to
confirm islanding. If this index is above 50%, the algorithm
further initiates (&lo%) the reactive power perturbation and
continues to calculate the correlation index. If the index exceeds
80%, the occurrence of islanding can be confirmed. The
proposed method is robust and capable of detecting the
occurrence of islanding in the presence of several DFPGs, which
are independently operating. Viability of the cross-correlation
method is verified by the simulation. Experimental results are
presented to support the findings of the proposed method,