Introduction System compensation is the process of designing a controller that will produce an acceptable transient response while maintaining a desired steady-state accuracy. These two design objectives are conflicting in most systems, since small errors imply high gains reduce system stability and may even drive the system unstable Compensation may be thought of as the process of increasing the stability of a system without reducing its accuracy below minimum acceptable standards 2022-2-3 22022-2-3 2 Introduction ¨ System compensation is the process of designing a controller that will produce an acceptable transient response while maintaining a desired steady-state accuracy .These two design objectives are conflicting in most systems ,since small errors imply high gains reduce system stability and may even drive the system unstable .Compensation may be thought of as the process of increasing the stability of a system without reducing its accuracy below minimum acceptable standards