Application of unified power flow controller in interconnectedpower systems-modeling, interface, control strategy, and case study

摘要

In this paper, a new power frequency model for unified power flowncontroller (UPFC) is suggested with its DC link capacitor dynamicsnincluded. Four principal control strategies for UPFC series element mainncontrol and their impacts on system stability are discussed. The mainncontrol of UPFC series element can be realized as a combination of thenfour control functions. The supplementary control of UPFC is added forndamping power oscillation. The integrated UPFC model has then beennincorporated into the conventional transient and small signal stabilitynprograms with a novel UPFC-network interface. Computer tests on an4-generator interconnected power system show that the suggested UPFCnpower frequency model and the UPFC-network interface method work verynwell. The results also show that the suggested UPFC control strategy cannrealize power flow control fairly well and improve system dynamicnperformance significantly