Patent ID: 7426456

Claim:
A method for optimal operation of a power plant comprising a plurality of physical plant components, where the method comprises the steps of: a) determining a trajectory of input values (u(τ)); b) determining, by simulation of the power plant behaviour, from the trajectory of input values (u(τ)), corresponding trajectories of process variables (P(τ)); c) computing a cost function (J[u], J[P]) as an integral of an objective function that comprises at least one trajectory determined in the simulation; d) iteratively repeating steps a) through c) with an optimisation module varying the trajectory of input values (u(τ)) until, for a trajectory of optimal control values (u*(t)), an optimised lower value of the cost function (J[u], J[P]) is arrived at, wherein in step b), a lifetime trajectory LTp(τ) of individual physical plant components is determined from the trajectory of input values (u(τ)) and wherein, in step c), the cost function (J[u], J[p]) comprises the term: ∫ t t + T ⁢ || R LT ⁢ ( τ ) ⁢ ( LTn ⁢ ( τ ) - LTp ⁢ ( τ ) ) || ⅆ τ , where LTn(τ) is a nominal lifetime trajectory of the individual physical plant components, R LT is a weighting matrix for determining a relative influence of each of the physical plant components, t is a present time, and T is a predetermined duration; and e) applying at least one optimal control value (u*(t)) from an optimisation module to the power plant to influence lifetime consumption of the individual physical plant components.