Through the analysis of soil erosion characteristics of power transmission construction project during construction in Xi'an plains as well as projects the relation between project constniction and soil & water conservation,the paper proposes several soil & water conservation measures to reduce the soil erosion in power grid construction and protect the ecological environment,and also provides a scientific basis and foundation for building the database of the soil erosion assessing.

This paper introduces the working principle,composition structure of DC circuit breaker used in HVDC engineering as well as its technical difficulties in interrupting course,makes a review on the allocation principle as well as operation mode of the DC circuit breaker in bipolar converter station for UHVDC transmission project,and gives a prospect that the DC circuit breaker may be used in the UHVDC project.