Control chaos in brushless DC motor via piecewise quadratic state feedback

The chaotic phenomenon in the brushless DC motor is revisited in this paper. For a specific real physical plant (i.e., the brushless DC motor), the main drawback of some existing chaos control methods is first analyzed. Then, a piecewise quadratic state feedback method is proposed for controlling chaos in the brushless DC motor model. In the proposed method, the direct-axis (or quadrature-axis stator voltage) is used as the control variable, and the piecewise quadratic state feedback is used as the control law. The control mechanism is illustrated and then the principle of parameters selection is discussed. Chaos in the brushless DC motor model can be satisfactorily eliminated by the proposed piecewise quadratic state feedback, and the speed of the motor can be stabilized to a constant value. This control method is simple and can be easily implemented. Simulation results verify the effectiveness of the method. © Springer-Verlag Berlin Heidelberg 2005.