29 December, 2017 at 4:24 pm at the power unit No 4 of Rostov NPP (ASE Group of companies, the Engineering Division of Rosatom, is the General Designer and Contractor) the operation on the transfer of reactor unit to the minimum controlled reactor power (MCRP) has been finished. The controlled chain reaction has been started: the ion chambers have documented the neutron flux that corresponds to the minimum controlled reactor power.
The carrying out of the physical tests at the MCRP will become the final stage of physical start-up of the power unit No 4 of RoNPP. During the MCRP the controlled chain reaction of fission starts when the neutron flux is fixed and the reactor capacity is less than 1%. During the reactor work at the MCRP the nuclear specialists will measure the real neutronic characteristics of the reactor core to prove the correspondence to the design parameters and the correctness of functioning of control and safety systems.
“We see that the personnel efforts bore fruit. The first neutron flux in the reactor core of reactor unit of power unit No 4 was recorded. In a little while we will start the operations at the turbine and generator, and connect the power unit to the network. I am sure that the undertaking created today will allow to carry everything out by the stipulated date”, the Director General of Rosenergoatom Concern Andrey Petrov noted.
“The transfer to the MCRP allows to carry out all necessary physical experiments in the critical condition of reactor unit (RU) to prove its design criteria”, the Vice-President on projects in Russia of ASE Engineering Company JSC Aleksey Deriy noted on the event’s importance. “Upon the results of the experiments the specialists will decide on the RU powerup.”
The transfer to the MCRP is one of the final operations of physical start-up stage of power unit No 4. It is to be recalled that from 20 December the hydrotests were carried out at the power unit. During the hydrotests the work of the main circulating pumps and other equipment of the primary and secondary circuit of the reactor unit at different temperature and pressure levels was checked. The loading of the nuclear fuel into the reactor started on 6 December. For 5 days and nights all 163 fuel assemblies were put at their proper location.
The Rostov NPP is an affiliate company for Rosenergoatom Concern OJSC. The plant is based at the Tsymlianskoe reservoir shore 13.5 km away from Volgodonsk. The NPP operates VVER-1000 reactors with the installed capacity of 1000 megawatts. The power block No.1 commenced commercial operations in 2001, with the second and the third power blocks to follow in 2010 and on September 17, 2015, respectively. The power block No. 4 is currently under construction.


Source: The Rostov NPP Information and PR Administration