Controllable DC-link bridge-type FCL for low voltage ride-through enhancement of converter interfaced DG systems

摘要: Recently penetration level of converter-interfaced distributed generation (DG) systems has been increased in utility and will be more so the future. To avoid grid instability, DG should have low voltage ride through (LVRT) capability considering codes. An efficient scheme is proposed to enhance LVRT DGs. The technique employs a single phase controllable DC-link bridge type fault current limiter (CD-BFCL), which placed DC side converter. During normal condition, CD-BFCL does not affect overall operation DG; whereas, during all AC faults including balanced, unbalanced, transient repeated network faults, converter output currents are limited desired level. In this way, capable even at zero faults. Analytics modes presented switching intervals demonstrate efficiency approach limitation over-current. method proved simulation studies PSCAD/EMTDC. Also, laboratory prototype developed validate possibility practical implementation CD-BFCL.