Evaluation of Short-cycle Power Output Fluctuation of High-Penetration Photovoltaic Power Generation Systems using Multi-Points Insolation Data

Abstract

By  using  the  multi-points  observation  data  of  insolation, this study evaluated the short-cycle fluctuation of total power  output  fluctuation  of  high-penetration  photovoltaic  power  generation system (PVS). First, this study evaluated the practical usability  of  so-called  1/√N  rule.  The  results  suggest  that  the  observation  points  should  be  placed  with  at  least  20  -  30  km  interval so that the average insolation fluctuation around the point is calculated by applying 1/√N rule. Then, taking the smoothing-effect  around  the  observation  point  into  account,  this  study  estimated  the  total  power  output  fluctuation  of  high  penetration  PVS. The horizontal global insolation data observed for a year at 61 points in the Japan central area was utilized. As the result, the total  power  output  fluctuation  including  only  shorter  cycles  than  32  min  is  smaller  than  1  %  of  the  installed  capacity  for  most  of  the  period  in  a  year.  Although  the  absolute  value  of  short-cycle  fluctuation  itself  may  not  be  significant  even  if  8  GW  of  PVS  is  installed,  the  reduction  in  the  contribution  of  controllable  utility  power plant due to the HP-PVS may cause the difficulty of LFC.