Patent attributes
A control system (1) for controlling a plant (2) comprises a feedback loop including an integrator (7); a signal generator (32); and a scaling unit (10). The feedback loop comprises an input suitable for connection to an output (18) of the plant. The integrator integrates a signal received from the input to generate a state signal x. The signal generator generates a periodic base perturbation signal (34) with an initial amplitude. The scaling unit generates a scaling factor (30) having a first value if the variance of the state signal var(x) is zero, or a second value if the variance of the state signal is non-zero, wherein the second value is proportional to (formulae 1) The scaling unit is arranged to multiply (16) the initial amplitude of the periodic base perturbation signal by the scaling factor to produce a state dependent perturbation signal (35, 36), which is applied to an input of the plant.
