Constrained optimum generator dispatch for fuel consumption minimization

The United States Marine Corps (USMC) utilizes Forward Operating Bases (FOBs) which employ multiple generation units, typically ranging from 2-200 kW in size, and primarily powered by JP-8 (similar to diesel fuel). It is often true that logistical support to deliver fuel is both expensive and dangerous. In typical deployment scenarios today, generation units are attached to a small group of loads, and are frequently operated far from their optimum efficiency. Future plans include combining multiple generators into a single microgrid. Since the generators have different fuel consumption curves, the dispatch of load to generation must account for unit capabilities, fuel consumption, and additional constraints, such as upper and lower operating limits. In addition, provision must also be made to handle fast load transients, typically with the use of “swing” generators. Furthermore, spinning reserve must also be available to cope with unanticipated load variations. This paper utilizes the Karush-Kuhn-Tucker (KKT) conditions to develop a scheme for economic dispatch of load to generators. The swing generator(s), base load generator upper and lower operating limits, and spinning reserve form constraints on the dispatch algorithm. The goal is to dispatch generators to minimize fuel consumption, while maintaining operating constraints for reliability.