Control method of Fabry-Perot interferometer frequency discriminator in double-edge wind lidar

The paper demonstrates a nonlinear design of the stabilization system of Fabry-Perot(F-P) interferometer which is a frequency discriminator used in double-edge wind lidar. First, a nonlinear model is set up to describe the F-P interferometer transmission peak locking problem. The disturbance caused by air pressure fluctuation, temperature change or mechanical vibration is characterized by the unknown external force acting on piezoelectric ceramics. For such a disturbance rejection problem, the nonlinear proportional-integral-derivative(PID) control is developed by utilizing arctan function to improve the feedback gain of the typical PID control design. The results show that, with the new controller, the discriminator can be stabilized much faster, and the steady-state error is approximatel