Role of acceleration control in heavy duty gas turbines during load rejection

In this study, role and importance of acceleration control in gas turbines investigated. Startup and load rejection are two main periods which turbine experiences major acceleration. It stated that acceleration control should be ignored during startup. But on the other hand, in case of load rejection, a proper control of acceleration can act quicker than load/frequency loop and reduces fuel flow to avoid any damage to gas turbine. Loop of acceleration needs an adequate short derivation time of speed derivation; otherwise, any small change in load can entrust the fuel flow control to acceleration loop, which is not fair. This paper demonstrates that a proper acceleration loop can detects load rejection much quicker, and even controls fuel flow at initial of this phenomenon so fast, and may compete to frequency relays. A simulation performed base on Rowen model to proof the claim.