دانلود Superimposed Adaptive Sequence Current Based Microgrid Protection: A New Technique

Abstract

In  this  paper,  an  adaptive  directional  overcurrent  relaying  technique  based  on  the  positive-sequence  (PSQ)  and negative-sequence  (NSQ)  superimposed  currents  is  proposed  for  microgrid  protection.  Due  to  the  change  in  mode  of  operation  of microgrid, the level and direction of prefault current are altered. On  occurrence  of  a  fault  in  any  line  section  of  the  microgrid,  coordination between the primary and backup overcurrent relays is  lost  due  to  variations  in  level  and  direction  of  fault  current.  With  inception  of  faults,  the  current  contributed  by  the  inverter based  distributed  energy  resource  (IBDER)  is  in  the  range  of  2  p.u. To solve protection coordination issue, this paper presents an adaptive overcurrent relay settings using PSQ and NSQ superimposed currents those are contributed during fault conditions.  Further,  the  direction  of  the  fault  is  obtained  using the new phase change between prefault and superimposed sequence  fault  currents.  The  proposed  technique  is  implemented on  a  dSPACE  processor  board,  which  is  connected  to  a  Real-Time Digital Simulator (RTDS) to carry out the hardware-in-the-loop (HIL) test. Extensive simulation and hardware results obtained for several microgrid operating modes indicate the effectiveness of the proposed technique. This proposed approach is independent of the voltage information.