Research On Applications Of UPFC In Nanjng 220kV West Loop

Unified flow controller (UPFC) is the typical representative of 3G Flexible Alternative Current Transmission System (FACTS), it is a variouscombination ofcontrollers which based on FACTS technology, UPFC is considered to be one of the most creative FACTS device, its success is known as themilestone in the development of FACTS. UPFC can make quick control and flexible regulationto the parameters of the power system which including active power, reactive power, voltage, impedance and power-angle, and it also can realize the real-time control and dynamic compensation to the AC power system.This paper analysesthe problems and their causes of Nanjing 220 kV western loop, and puts forward solutions and makestechnical and economic comparison. UPFC is recommended for the solution to improve the power capacity. Through analysis on principle andbasic control modes,Itverifis the multiple functions of power flow controlling and adjusting of UPFC, and summarizes theadvantage of UPFC, and demonstrates the engineering feasibility of UPFC based on Modular Multilevel Converter (MMC).On the basis of calculation results to Nanjing 220 kV western loop in production year and long-range year of UPFC, requirement of various modes of power flow adjusting is comprehensively considered to choose reasonable sizes of UPFC. To lay a foundation of application of UPFC, this paper also carries out the researchs on engineering application of UPFC which including main connection, general layout, impacts on the safety of power grid, etc.