The Application Research Of A Economical FCL In Power System

With China’s rapid economic and social development, the construction ofUHVAC and UHVDC power grid interconnection between the region grid moreclosely. The rapid growth of the load, low-voltage system transformer capacity rapidly.In addition, the distributed power such as wind power generation, photovoltaic,micro-gas turbine, micro turbine, diesel generators, fuel cells, etc. continue to beincorporated into the power grid, power and flexible technical measures can make thepower grid and grid transmission capacity is improved, but also led to the rise of thepower system in the short-circuit power and short circuit current. Grid short-circuitcurrent levels continue to increase, will the power grid safe and stable operation hasbrought a great deal of hidden dangers and hazards, and therefore must take effectivemeasures to timely limit the fault current. Development of domestic research focuseson the response to short-circuit current limit fault current limiter FCL (Fault CurrentLimiter), because it can limit the short circuit capacity of the grid to reduce the circuitbreaker and other high voltage equipment, dynamic thermal stable burden andimprove its reliability and service life, reducing the design capacity requirements ofthe grid on the design requirements of a variety of electrical equipment (circuitbreakers, transformers, switches, etc.) and grid structure is more flexible operationmode, and save a lot of pre-construction cost, good performance, has broadapplication prospects. At home and abroad have been a number of research institutesand enterprises engaged in related research, some of them in low-voltage equipmentin the test run.This paper presents a new type of flexible fault current limiter design and itscontrol strategy: First, a brief introduction of the new topology of fault current limiterworks; on this basis, current limiting performance is verified by simulation and theimpact on power system stability; and made a fast fault detection algorithm and a newcontrol strategy of the FCL, design the control system. Finally, the220kV substationshort-circuit current calculation and analysis, design of the optimal configuration ofthe substation FCL program, and simulation analysis.Through the above study,indicating that the first impact of the flexible fault current limiter can quickly andefficiently to limit the fault current peak and steady-state peak, but also reduces the power angle oscillations, power system transient stability. Normal operation of systemprotection configuration, the economy is good, has been widely used in power system.