Dispersed generators providing ancillary services through power electronic interfaces: A hybrid system

Recent advances in power electronic technology offer potential solutions to several technical and economical problems in distribution networks. In particular, this technology used for interfacing dispersed energy resources to distribution grids has led to the provision of some ancillary services for power quality (PQ) improvement (compensation of waveform distortions, unbalances, and so on). In this paper, a hybrid system including a fuel cell and an ultracapacitor, interconnected to the distribution network through power electronic interfaces, is proposed for active power and ancillary service provision. It can operate with both dasiasystem strategiespsila aimed at compensating for the disturbances in the whole system or in some privileged areas of the network and dasialocal strategiespsila for the compensation at a specified bus. Computer simulations are performed on an actual distribution grid demonstrating the effectiveness of the compensation actions.