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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Man-Sung Yim, John M. Christenson
Nuclear Technology | Volume 100 | Number 3 | December 1992 | Pages 361-377
Technical Paper | Reactor Operation | doi.org/10.13182/NT92-A34731
Articles are hosted by Taylor and Francis Online.
The control characteristics of a load-following pressurized water reactor are investigated through the application of a nonlinear optimization method to a simplified plant simulator. A model describing the power level control and power distribution control is developed and used to formulate an optimal control problem. In the optimal control problem formulation, all of the safety and system operating limits are included as hard constraints, and the multiple objective functionals are combined into a single performance index. The differences in the calculated optimal load-following control strategies are investigated for the cases of steady-state Tavg (coolant average temperature) program operation and variable Tavg operation at both beginning-of-cycle and near end-of-cycle conditions. The results show that the amount of boron control action for the demanded load variations can be significantly reduced when variable Tavg operation is incorporated into the control policy.