DYNAMIC SIMULATION OF STEAM TURBINE CONDENSER SYSTEM FOR PROPOSED PLANT ANALYSER OF A NUCLEAR POWER PLANT

摘要

A natural circulation vertical pressure tube type boiling light water cooled and heavy water moderated reactor has been designed with various advance safety features. This proposed reactor is to be operated in reactor follows turbine mode. Pressure and velocity fluctuations in the main steam line of nuclear power plants have a large influence on the safety and stability of the whole system, particularly in the direct steam cycle of modern BWRs. A detailed plant model of main heat transport system (MHT) with steam drum pressure and level control has been developed with steam line modeling up to the governor valve. As a part of plant analyser development to investigate the dynamic response of the integrated system, an exhaustive model of steam turbine and condenser components has been developed. These steam turbine and main condenser models have been coupled together and tested for full power steady state design conditions. This integrated module has been used to carry out transient analysis with the change in inlet steam flow following load change. Further, this model has also been tested for condenser cooling water transients like increase in the condenser cooling water temperature and cooling water flow rate. The paper highlights the detail modelling of the turbine and condenser system in RELAP5 followed by transient responses of above-mentioned events in terms of turbine torque and condenser back pressure along with other parameters.