Novel islanding detection method for inverter-based distributed generators based on adaptive reactive power control

摘要

Here, a novel active islanding detection method for inverter-based distributed generators (IBDGs) is presented. In order to reduce the disturbance in grid-connected mode and realise rapid and effective detection during islanding, the linear reactive power disturbance is utilised in the proposed method and its slope can change adaptively. The voltage variation and correlation factor between reactive power disturbance and frequency variation are proposed as criteria for disturbance slope adjustment. In addition, considering IBDGs located at different positions can detect the same frequency variation characteristics, the value of the frequency is used as the criteria to control the disturbance values, which can guarantee the synchronisation of disturbances added on different IBDGs without the need of communication. According to the anti-islanding test system recommended in IEEE Std.929-2000, the effectiveness of the method has been validated with several case studies in the power systems computer-aided design (PSCAD)/EMTDC environment.