Multi-Variable Control of the GE T700 Engine using the LQG/LTR Design Methodology

In this paper we examine the design of scalar and multi-variable feedback control systems for the GE T700 turboshaft engine coupled to a helicopter rotor system. A series of linearized models are presented and analyzed. Robustness and performance specifications are posed in the frequency domain. The LQG/LTR methodology is used to obtain a sequence of three feedback designs. Even in the single-input single-output case, comparison of the current control system with that derived from the LQG/LTR approach shows significant performance improvement. The multi-variable designs, evaluated using linear and nonlinear simulations, show even more potential for performance improvement.