In the present paper, we discuss a setpoint tracking control problem for a plant with discrete actuators. When a conventional linear servo controller is applied to the plant, undesirable periodic vibrations similar to the limit cycle occasionally occur in the output response caused by synergy with the integration of the steady-state tracking errors and the quantized errors of the control inputs. To prevent an undesirable response, a novel control method is proposed, in which the controller switches the control structure based on the value of the Lyapunov function. The effectiveness of the proposed method was verified through numerical simulations.
