Non-affine nonlinear system control method containing unknown nonlinear function

The invention discloses a method for controlling a non-affine nonlinear system containing an unknown nonlinear function, which comprises the following steps of: firstly, designing a fast-varying subsystem through a backstepping method for the non-affine nonlinear system containing the unknown nonlinear function, so that a closed-loop system is converted into a singular perturbation standard type; and then solving degradation subsystems, namely a boundary layer subsystem and an order reduction slow-varying subsystem, on a fast time scale and a slow time scale respectively. Under a slow time scale, the system is converted into an integral chain form containing an unknown nonlinear function under an error coordinate system, and on this basis, an observer of the system is established and a controller of the system is designed. According to the method, a system containing an unknown nonlinear function is considered, a non-affine structure is reserved, complex calculation is avoided through the adopted method, and