Analysis of chattering in continuous sliding mode control

An analysis of two most popular continuous sliding mode algorithms: the power-fractional sliding mode algorithm and a second order sliding mode algorithm known as the super-twisting is carried out in the frequency domain with the use of the describing function method. It is shown that in the presence of an actuator, the transient process converges to a periodic motion. Parameters of this periodic motion are analyzed. A few examples are considered to illustrate the obtained results.