Potential Solutions for Minimizing Voltage Sags Caused by DG Anti-Islanding Protection

This paper proposes solutions to the problem of voltage sags caused by distributed generators anti-islanding protection. This is a recently identified power-quality (PQ) concern resulting from the increasing penetration of distributed generators into distribution networks. This problem has been previously investigated by the authors and it was revealed that it can seriously affect PQ indices as well as distributed generators reconnection procedures. However, no solutions have been formerly proposed or investigated. In this context, this paper investigates several potential solutions to be adopted by the utility and/or by the DG owners and presents a thorough evaluation of their main advantages and disadvantages. Besides this investigation, simple step-by-step procedures for assessing the effectiveness of each solution are described. The presented studies and procedures will guide the utility engineers in decision-making process associated with the choice of reasonable mitigation techniques to this problem.