Köroğlu, HakanMorgül, Ömer2016-02-082016-02-0820000191-2216http://hdl.handle.net/11693/27631Date of Conference: 12-15 December 2000Conference Name: 39th IEEE Conference on Decision and Control, IEEE 2000Linear Quadratic (LQ) controller design is considered for continuous-time systems with harmonic signals of known frequencies and it is shown that the design is reducible to an interpolation problem. All LQ optimal loops are parametrized by a particular solution of this interpolation problem and a (free) stable/proper transfer function. The appropriate choice of this free parameter for optimal stability robustness is formulated as a multiobjective design problem and reduced to a Nevanlinna-Pick interpolation problem with some interpolation points on the boundary of the stability domain. Using a related result from the literature, it is finally shown that, if there is sufficient penalization on the power of the control input, the level of optimum stability robustness achievable with LQ optimal controllers is the same as the level of optimum stability robustness achievable by arbitrary stabilizing controllers.EnglishControl designH∞ controlHarmonic signalsLQ controlControl system synthesisOptimal control systemsRobustness (control systems)System stabilityTransfer functionsLinear quadratic controlLinear time invariant systemsLinear control systemsConference Paper10.1109/CDC.2000.912289