摘要

With the connection of wind generators to the distribution network, the load flow and the characteristics of the fault currents of the distribution lines have been changed. Due to the introduction of the chopper circuits after faults, wind generators'positive and negative sequence impedances are not equal any more, which leads to the loss of the foundation of the relays'setting principles. In this paper, the characteristics of the phase-to-phase fault and three-phase fault at different locations of the weak-infeed distribution lines connected with wind generators are analyzed. Hence, while calculating the setting values of the instantaneous overcurrent protections and time delay instantaneous overcurrent protections of those lines, correction factors are utilized to overcome the influences of the wind generators with the help of the real-time online setting of the adaptive protection. Finally, a simulation is carried out to validate the effectiveness of the proposed scheme.

全文