A novel passive islanding detection scheme for distributed generations based on rate of change of positive sequence component of voltage and current

Islanding operation is one of serious hazards of distributed generation (DG) applications. According to IEEE 1547 standard, its occurrence must be detected within two seconds. This paper presents a novel passive islanding detection method based on rate of change of positive sequence component of voltage (RCPSV) and rate of change of positive sequence component of current (RCPSC) acquired at point of common coupling (PCC) of the targeted DG. Whenever the RCPSC and RCPSV are not equal to zero, their change of magnitudes is continuously compared to predetermined threshold values. If both values of RCPSC and RCPSV exceed the predetermined threshold values, it is concluded that the islanding condition has occurred. Otherwise, it is considered as a non-islanding event. The performance of the proposed method is investigated on a sample network in the presence of doubly fed induction generator (DFIG) based wind turbine and synchronous diesel generator DGs by MATLAB/Simulink software. Different nonislanding case studies are taken into account to evaluate the effectiveness of the proposed approach. The simulation results show that the proposed method has advantage of detecting the islanding rapidly and accurately even with zero non-detection zone (NDZ).