Design of a Rapid Tangent Sigmoid Function Tracking Differentiator

Aiming at the shortage of differential accuracy of rapid tangent sigmoid tracking differentiator in tracking input signal and the slow convergence of tangent sigmoid tracking differentiator near the equilibrium point and the poor ability to suppress noise, a rapid tangent sigmoid tracking differentiator is designed by choosing tangent sigmoid function, linear function and terminal attractor function. The frequency domain characteristics are analyzed by sweeping test, and its stability is proved. In the tracking differentiator of rapid tangent sigmoid function, the continuous function form of linear and non-linear combination effectively improves the tracking and differential ability of the system, and the terminal attractor function effectively suppresses the noise, so that the tracking input signal has high precision and small error. The linear function accelerates the convergence speed when the state is far from and near the equilibrium point, and the form is simple. The numerical simulation shows that the tracking differentiator with fast tangent sigmoid function has excellent performance.