Control performance enhancement of gas turbines in the minimum command selection strategy

Three novel methods, named α, ζ and ϵ, are suggested in this paper to recover the performance loss during switching in the gas turbine control systems. The Minimum Command Selection (MCS) in the gas turbine control systems prompts this performance loss. Any step towards more productivity with less aging factors have a great impact on the gas turbine's lifetime profit and vice versa. Although many hardware upgrades have been studied and applied to accomplish this, in many cases a low-risk manipulation in the software may yield equivalent achievement. State of the art gas turbine control systems are supposed to handle various forms of disturbances, several operation modes and relatively high transients of the gas turbines. The proposed methods dynamically limit the inactive control loop command and utilize the corresponding loop error to optimally switch the loops. The optimality infers a fuzzy choice based on the designated performance criteria. They demonstrate enhanced performance in comparison with conventional techniques such as static or dynamic saturation proportion to active command, integrator fast rewind, and PI tracking mode. An identified model of W251-B2 gas turbine with robust controllers is exploited to evaluate the empirical authenticity. They exhibit superior performance in comparison with traditional MCS and decrease the over-temperature around 9^oC[2%], as the load control switches to the temperature control. The proposed methods provide pragmatic and promising tools in the designer's hands to adapt the methods based on the application requirements.