Abstract: The basic characteristics of nuclear power station steam turbine with its cycle are introduced, as well as the measurement methods of steam moisture. The effect of the changes of steam moisture on steam turbine inlet enthalpy, corrections of test results and total test uncertainty were analyzed. It is presented that in the pressurized water reactor nuclear power turbine performance test the design moisture at outlet of steam generator can be used to calculate the inlet steam moisture under certain circumstances as an alternative method to take place of direct measurement of moisture.

Key words: pressurized water reactor, nuclear power steam turbine, moisture, thermal performance test