The white paper demonstrates the feasibility of industrial micro- grids by design of an actual industrial network with on-site distributed generation to temporarily keep crucial consumers in operation in islanded mode, and to increase reliability in the case of blackouts.
The objective of this white paper was to determine the design requirements for safe and reliable operation of a microgrid within an existing industrial network which is connected to the public grid and which can also function in islanded operation. To do this a typical industrial 20/0.4 kV grid model was constructed in a network planning tool. Various generators, such as those for biomass, diesel and gas, their controllers, and consumers were modelled in order to study dynamic stability. Furthermore, the existing protection system was analyzed within the simulation model. In addition to a variety of load flow and time domain simulations, a fault analysis was also conducted to verify the reliability and the stability of the microgrid. Advanced control strategies have been developed together with a comprehensive protection system to allow both grid connected operation and islanded operation.