Performance test and analysis after high pressure turbine retrofit for Maanshan nuclear power plant Unit 1

The purpose of the performance test for Unit 1 of Maanshan nuclear power plant was to determine the electrical output and heat rate after the retrofit of the high-pressure turbine during the refueling in 2012. The performance test was conducted in order to verify that the actual improvement in electrical output resulting from the replacement of the high-pressure turbine meets the vendor’s guarantee. A total of two performance test runs was conducted in accordance with the American Society of Mechanical Engineers performance test code (PTC) 6. The measured electrical powers for the two test runs were 977.4 and 975.0 MWe, respectively, and the average value was 976.2 MWe. After correcting the electrical power to the rated conditions specified in the performance test procedure, the gross electric output was 983.2 MWe. The corrected heat rate for the two performance tests were 10365 and 10353 kJ/kWh, respectively. The deviation between two corrected heat rates was 0.11%. Since the acceptable deviation between two test runs required by PTC 6 is no more than 0.25%, the quality of test results is acceptable. Moreover, the performance test results also demonstrated that the improvement in gross electrical output was 17.6 MWe, which was higher than the contract guarantee of 10.0 MWe.