Generalized discrete decoupling and control of MIMO systems

Abstract

This paper proposes an efficient discrete-time decoupling algorithm for multiple input multiple output (MIMO) systems having strong coupling between inputs and outputs. A design method for discrete decouplers is proposed to eliminate the cross-coupling effects present in MIMO systems. The proposed decoupling technique is based on relative gain array (RGA) approach of MIMO system. In order to perform closed-loop control, individual discrete-time PID controllers are designed based on Kharitonov theorem for each of the SISO control loops of the resulting decoupled MIMO system. The closed-loop performance of the MIMO system under consideration is investigated in simulation and in real time which illustrate that the proposed decoupling algorithm satisfactorily nullifies the interaction between the inputs and outputs. The control scheme exhibits perfect tracking of the reference commands even in presence of disturbances. Twin rotor MIMO system (TRMS) is considered as the real-time example to validate the proposed method. Further, the performance of the compensated TRMS system is analyzed in frequency domain in presence of common actuator nonlinearities dead zone and saturation together. The performances of the controllers are found to be efficient even in presence of actuator nonlinearities.

Image stabilization of airborne inertial stabilization platform using fast steering mirror

“…Unfortunately, state of the art studies on the MIMO decoupling control conclude that, although the dynamic coupling effect can be suppressed to some degree, it is doubtful if the decoupling measures are effective enough to guarantee the required image stabilization accuracy for the AISP. [16][17][18][19] Therefore, in the first place, assessments need to be made on how much the inter-axis dynamics are coupled with each other.…”

Interaction measures in a three input integrated DC-DC converter

“…The interactions of TIID converter is quantified systematically using dc-gain and gramian based measures. Thus in this paper an attempt is made to analyse the interactions of integrated converter [8][9][10][11][12][13][14][15] under parameter variations. The impact of parameter variations on quantification is shown graphically.…”