ℌ∞-suboptimal tracking control with integral action and load estimation applied on a Boost-converter/DC-motor combination

In this contribution, a Hfr_infin-controller is devised for the tracking of a reference trajectory in a SISO-system. To this end, a Hfr_infin suboptimal set-point control concept for bilinear systems is adapted and generalized for tracking purposes resorting to the overall error dynamics of the respective time-varying system. The presented controller incorporates integral action on the angular shaft velocity and iISS (integral Input-to- State Stability) is guaranteed for the closed-loop system subject to non-zero disturbances. The integrator is to compensate for measurement noise, to compensate for load torque changes we introduce a load estimation scheme. Also iISS is shown for the closed-loop system under disturbances when completed with integrator and estimator. The approach is applied to a Boostconverter driven DC-motor, where the angular shaft velocity is the output to be tracked.