Setup experience in commissioning hydraulic control system of turbine K -1200-6,8/50

The construction of new nuclear power plants under the NPP-2006 project required Leningradsky Metallichesky Zavod (LMZ) to implement an electronic and hydraulic turbine regulation and protection system (TRPS) in the design of a large capacity condensing turbine K-1200-6,8/50, based on the experience, design and circuit solutions for a similar system of a high-speed turbine-analogue K-1000-60-3000 manufactured by LMZ. Despite the preservation of the turbine layout in relation to the turbine-analogue (2LP module + HP module + 2LP module), the turbine control concept through the TRPS and the available references at the stage of commissioning of the Novovoronezh NPP-2 power units (before the power unit was turned on to the grid), as experience has shown, there were cases of incorrect operation of the TRPS due to the ambiguity of the assembly or hidden inconsistencies. The elimination of the causes of incorrect operation of hydraulic assemblies is often directly related to the search for the root cause "from the inside", i.e. disassembly of equipment is required. The presented article shows cases of incorrect operation of the TRPS and ways to solve them from the experience of commissioning on a high-capacity turbine K-1200-6,8/50 with a brief description of the problematic TRPS hydraulic components, the amount of refinement of structural elements. The experience of commissioning described in this article is still relevant today due to regular scheduled preventive repairs at commissioned power units of the NPP-2006 project, during which a routine audit of the hydraulic elements of the steam distribution organs is carried out, as well as a pre-start check of the interaction of the hydraulic and electronic parts of the TRPS. In addition, the commissioning of nuclear power plants with turbine K-1200-6,8/50 is currently underway abroad (in People's Republic of Bangladesh) where the described experience can be applied on occasion.