Abstract: Aiming at the control problem of time-delay in fractional order systems, the Smith predictor fractional order PI(Proportion Integral) control scheme is introduced for a time-delayed systems in case of no eliminating the time-delayed part. Taking into account the stability of the fractional order systems with time-delayed, the Smith predictor control can effective overcome the time delay for fractional order systems. The simple rules of parameter tuning of fractional order PI controller are given, which have certain practical application value. The influence of the order for fractional order system on the system convergence time is analyzed. The numerical simulation results has verified the effectiveness and feasibility of the conclusion.

Key words: fractional order system, time-delayed system, Smith predictor control, fractional order proportion integral (PI) control, parameter tuning