RDG in weak grid for desalination plant. System topology and control strategy

Renewable Distributed Generation (RDG), such as production of electric power near to the load, is particularly beneficial when the distribution network is “weak” against specific demands, as in potable water production systems connected to coastal electrification networks. In these areas, the wind resource may be suitable for this type of generation. This work proposes the topology, the operation mode and the control strategy for a Reverse Osmosis Desalination Plant, “assisted” by a weak AC grid and “powered” by a variable speed wind turbine based on a three-phase BDFIG machine. The wind energy conversion is optimized through adequate control of the generator. The high pressure pump of the desalination plant is controlled for the maximum utilization of the generated power. The electric power fluctuations due to win turbulence are compensated through a controlled energy storage system based on a flywheel. The system configuration, its operation mode and control are presented.