Abstract: The paper presented the rusults of a study to evaluate various exsisting control scheme of variable speed pumping units for tight operation of pipeline. The defects and insufficiencies of these scheme are reviewed, A new control scheme to apply in both steady and unsteady state is introduced, and it can suppress waterhammer in combination with wavespeed regulating devices. The results of a computer dynamic simulation show that this scheme is resonable and accurate. It provides an effective means of smooth operation and automatic regulation for pipeline.