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In the thermal circuits of domestic steam turbines, mixing-type low-pressure heaters (LPH) with free-flow jet water distribution and counter-flow of water and steam are widely used. The choice of the counterflow variant of the media movement ensures the most efficient heat transfer. However, the technical problem of ensuring reliable operation of LPH in the entire range of design loads of TPP and NPP power units is still relevant.During the commissioning and operation of mixing-type LPH in 800÷1200 MW turbines of TPP and NPP, the presence of metal knocks in the zone of the check valve, hydraulic shocks in the heating section were revealed. A priori, these phenomena indicated design flaws in LPH or manufacturing defects in their production. Research carried out by NPO CKTI specialists showed that periodic hydraulic shocks in the heating section and metal knocks occur as a result of uneven distribution around the circumference of the main condensate and steam supply. This leads to a breakdown of the check valve and the destruction of perforated plates and off-design heating of water in the volume of the annular LPH water chamber. To clarify the causes of the damage, develop recommendations for the reconstruction of the apparatus and further account for the design, two series of experimental studies were carried out on mixing-type heaters of 800 MW turbine units PNSV-2000-1 and PNSV-2000-2 manufactured at PJSC Krasny Kotelshchik. The purpose of the experimental studies was to determine the change in the water level in the water chamber and the heating of the main condensate in the elements of the heating compartment during normal operation of the power unit at loads of 400÷850 MW. Based on the results of the research, the method for calculating the mixing-type LPH has been refined, taking into account the revealed non-uniformity of water heating in the water chamber, recommendations for their reconstruction have been developed and implemented.

One of the most important issues for modern domestic power industry is the creation and further widespread introduction of solid propellant energy units for super-critical steam parameters with high efficiency (43–46%) and improved environmental parameters. This will significantly reduce the use of natural gas.At the same time, one of the major drawbacks of the operation of pulverized coal power units is the need to use a significant amount of fuel oil during start-up and shutdown of boilers to stabilize the burning of the coal torch in the variable boiler operating modes.In this regard, solid fuel TPPs need to be provided with fuel oil facilities, with all the associated problems to ensure the performance (heating of fuel oil in winter), reliability and safety. All of the above problems increase both the TPP capital construction costs, and the electricity generating cost.A practical solution to the above problems at present is the use of a plasma technology for coal torch ignition based on thermochemical preparation of fuel for combustion. The materials of the developments of JSC “NPO CKTI” on application of plasmatrons in boilers of thermal power plants at metallurgical complexes of the Russian Federation are also considered.Plasma ignition systems for solid fuels in boilers were developed by Russian specialists and were introduced at a number of coal-fi red power plants in the Russian Federation, Mongolia, North Korea, and Kazakhstan. Plasma ignition of solid fuels is widely used in China for almost 30% of power boilers.The introduction of plasma-energy technologies will improve the energy efficiency of domestic solid-fuel thermal power plants and can be widely implemented in the modernization of boilers.During the construction of new TPPs, the construction of fuel oil facilities can be abandoned altogether, which will reduce the capital costs of the construction of thermal power plants, reduce the construction footprint, and increase the TPP safety.

Topical issues of creating test benches for power drive units are considered. The results of testing a hydraulic dynamometer with the aim of clarifying its characteristics are presented. When creating test benches, it is important to choose the right power damping system with its accurate measurement. For these purposes hydraulic dynamometers (HD) are used. The domestic industry has not yet mass-produced them, experimental development is underway. In this regard, it seems appropriate to use imported diesel engines, for example, Japanese-made, of type CFT-9.0 manufactured by Fuchino Co Ltd. This equipment has a commercial preference over other foreign manufacturers. This article discusses the principle of HD operation, its design features, the identified shortcomings and ways to address them, the results of tests of the gas engine on a special bench of JSC «NPO CKTI».The tests carried out made it possible to verify the operability of the acquired HD, to determine the dependence of the HD power on the rotation frequency, the dependence of the cooling water flow rate on the HD power and the dependence of the HD power on the steam flow rate to the steam turbine drive.The results obtained indicate that the HD of type CFT-9.0 manufactured by «Fuchino Co Ltd» can be recommended as a hydrodynamic power absorber with its high-precision measurement in a wide range of rotation speed, modes and power consumption up to 8.5 MW.