Nuclear steam turbine use wet steam as working medium, which is unable to determine the enthalpy drop type relative internal efficiency through exhaust enthalpy of steam, but the power type relative internal efficiency avoids this question. This paper introduced the calculate method of power type relative internal efficience, and then took a 900MW nuclear steam turbine for example, calculated the power type relative internal efficiency when the factors of regenerative system are changed. The result shows that when the factors of regenerative system are changed in a large range, the power type relative internal efficiency is nearly changeless, so the effect of regenerative system on relative internal efficiency can be neglected. At last, the independence between relative internal efficiency and ideal cycle heat efficiency is calculated and analyzed. (C) 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Hainan University.
