Disadvantages existing in current automation systems of HPP (hydropower plants) are analyzed. Based on Fieldbus and IAM (i ntelligent actuation and measurement) technologies

a type of ICMMS (intelligent control maintenance technical management system) for HPP is presented

and its structure

functions

characters

implementation methods are discussed. For the sake of current technical feasibility and future development

HSAS（hybrid smart automation system) as a new type of automation systems is proposed for HPP. T he overall structure of this system is based on fully distributed Fieldbus archi tecture. Not only the Fieldbusbased IAM components

but also the traditional a utomation devices can be integrated into this system. So the HSAS is a fully dis tributed and realizable solution for the automation system of HPP. A HSAS sol ution for largescaled hydropower generating units is also presented

with int egrated

distributed

open

and intelligent features.