Short-term energy storage for power quality improvement in weak MV grids with distributed renewable generation

The intermittent and stochastic nature of renewable energy sources impose several challenges for the operation of electrical networks, and affect power quality levels as well. This paper addresses one of the issues associated to power quality in electrical networks: voltage flicker. The main contribution of the paper fall in the proposal of a methodology for addressing the location in the network and the sizing of an active filter for flicker filtering. The designed active filter is based on controllable and bidirectional power electronics. Also, it includes energy storage capability, so as to maximize flicker filtering effectiveness by performing both active and reactive power regulation.