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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.
A. A. El-Bassioni, C. G. Poncelet
Nuclear Science and Engineering | Volume 54 | Number 2 | June 1974 | Pages 166-176
Technical Paper | doi.org/10.13182/NSE74-A23404
Articles are hosted by Taylor and Francis Online.
The theoretical minimal time modal control strategy to suppress xenon oscillations in nuclear reactors was found to be of the Bang-Bang type. Such control policy implies instantaneous variation of the control poison between two extreme values. The switching action depends on exact knowledge of the location of the reactor state in the phase plane. The state is related to the measured axial offset, and the concept of axial offset phase plane is introduced. The main features of this phase plane can be constructed using a semi-operational method. Using the Carnegie-Mellon University xenon spatial control simulator, optimal and off-optimal control policies were tested and the capability to suppress the oscillation was demonstrated. Some of the attractive features of this suggested method are the simplicity of control policies, use of reactor output data, and the ability to initiate the control action once the oscillation is detected and to predict beforehand the outcome of the control decision, thus increasing the operator capacity to modify his decision.