Strategic self-dispatch considering ramping costs in deregulated power markets

Summary form only given. Ramp rates of generators are specified within elastic range of the strength of the shaft to safeguard the rotor from fatigue. These limits can be exceeded at the risk of reducing the rotor life. Such effects on the rotor life can be compensated by incorporating ramping costs. Power demand and power price in deregulated power markets have shown a tendency of sudden wide excursions over short intervals of time. The ability to respond to such changes can be rewarding. This provides the motivation to utilize the ramping rates beyond elastic limits. This paper studies the strategic use of ramping rates beyond elastic limits in a power producer´s self-dispatch in a power market. A set of ramping processes has been developed from ramping-cost versus ramping time relationships to derive the total operation cost including ramping costs. Theoretical analysis has been conducted for the selection of the optimal ramping process under different conditions. A numerical example is presented to highlight the potential benefits from the use of optimal ramping processes. It is seen that the benefit from the strategic use of ramp rates not only depends on the high price in the power market but also on the initial loading of the generator which limits the capacity available for dispatch.