Switched integrator control schemes for integrating plants

In this paper, we compare and analyse three switched integrator control schemes for integrating plants. The schemes attempt to circumvent a fundamental limitation of linear time invariant (LTI) control, namely, that the closed loop response to a step change in the reference must overshoot if both the controller and the plant contain an integrator. We show that, for a simple example, the switched schemes all have significantly less overshoot than their LTI counterpart. The stability properties of the schemes are also studied. It is first shown that bounded input bounded state stability is guaranteed. Sufficient frequency domain conditions for asymptotic stability are then derived using passivity analysis.