Design And Research On Series Fault Current Limiter With Compensation

With the expansion of the scale of the power system,the accident caused by short circuit fault in the power grid is also increasing and the overcurrent in the circuit should be limited when the short circuit fault occurs.The fault current limiter has good current limiting performance and the saturated core type fault current limiter has the advantages of good current limiting effect and easy easy to match with the auto-recloser.It has a good application prospect.A type of saturated iron-core high temperature fault current limiter based on TCSC structure is reasearched in the research.The voltage transient fall can be compensated and the current limiting capacity of the current limiter can be improved when the equipment is used.Core model is built by JMAG and its current limiting capability is verified by Matlab/Simulink.The topology and parameters of the series compensation part are designed,and its series compensation ability and current limiting capability are verified through Matlab/Simulink.The environment of bias current is nonlinear and complex that it has even electromotive force.In order to effectively control the bias current,a current control system of the saturated iron-core type fault current limiter is designed which based on hysteresis control and fuzzy control.Simulation analysis through Matlab/Simulink is carried out.It is concluded that fuzzy control has higher controlling efficiency through comparison.Then,experimental platform based on DSP of TMS320F28335 has been designed.The platform concluded the signal acquisition circuit,conditioning circuit,IGBT drive circuit,lower machine software and upper moniter software.The excellent characteristics in steady state operation and fault current limiting of fault current limiter are proved in our experiments.The saturated core type fault current limiter based on the modified TCSC structure can effectively limit the short circuit current and compensate the voltage drop of the power supply.It will not produce large switching loss in the process of steady state operation,and it has a good application prospect.