Cruise missile altitude control system design using phase-lead compensator

This article discusses the design of a cruise missile altitude control system using phase-lead compensator as the controller. The design objectives for this controller are to stabilize the system, to accept low-frequency and reject high- frequency, and to minimize overshoot to obtain smoother path result. A simple single-axis altitude model is given. The system is analyzed using frequency response method. Based on the closed- loop transfer function a phase-lead controller is designed. The controller causes the closed-loop to become a third order system. However, it behaves like a first order because the dominant pole is located at the real axis of -1.016. The simulation results show that the controller can meet our three design objectives with a very small overshoot of 1.49%. The system rejects higher frequencies above 400 rad/s by reducing the higher frequency inputs to under 20% of the original amplitude.