DISTURBANCE ACCOMMODATING CONTROL OF A VARIABLE-SPEED TURBINE USING A SYMBOLIC DYNAMICS STRUCTURAL MODEL

An investigation has been made into the performance of Disturbance Accommodating Control designed for a structural model with rotor speed as the only degree of freedom. A comparison has been made with the same controller attempting to regulate speed of a structural model with four degrees of freedom (including tower and blade deflection). The latter model was constructed using a symbolic modeling method, capable of providing the system equations of motion explicitly. For the current investigation, however, only simulation response was analyzed. The results show unstable closed-loop behavior of the multivariable system, due to excitation of collective blade flap-wise motion from the blade pitch controller.