Control interaction mitigation for the unified power flow controller

This paper establishes that dynamic interactions can occur between multiple UPFCs installed in power systems. The existence of the dynamic interactions can adversely affect the overall system performance and lead to system instability. This paper identifies two types of interactions among FACTS controllers: low frequency inter-area interaction and high frequency controller interactions. Several control approaches are proposed to mitigate these interactions. The IEEE New England 10-machine 39-bus system is used to demonstrate the existence of the control interactions and illustrate the effectiveness of the proposed interaction mitigation controls.