In article the existing methods of decrease in a technological minimum for work of combined heat and power plant in the conditions of a power supply system are considered, assessment of their efficiency on the example of the power unit of the Yuzhnaya CHP-22 with the turbine T-250/300-240 of PJSC TGC-1 is carried out, and also the main recommendations about the range of application of these methods are made.  By means of a specialized program complex the settlement analysis of the main methods of the most effective passing of minima of electricity consumption is made for combined heat and power plant, in particular transfer of the turbine to the rotor pro-rate mode.

The article deals with the properties of coal and the field of application, the development of technology for the production of charcoal, and also the installation for the processing of timber materials of the timber industry. A description of the technology and instrumentation of the process of wood waste in a continuously operating vertical retort is presented.

Ash dumps of traditional types are permanent air and water environment pollution sources in which accumulated colossal amount of ash-slag waste by now. Stricter environmental requirements raise the question about existence of coal power stations in the future. A radical solution of the problem can be wide-scale ash-slag recycling. The ash-slag must supply to recycling plant in separate (in other words differential) form directly from coal power station boiler units and separate storing ash-slag dumps as well. The separate storing ash-slag dump would became a buffering hub adjusting differential ash and slag inflow during the year. In this case, an excessive amount of the ash and slag waste will be stored in winter season and unloading in summer by the separate storing ash-slag dump. The most complete recycling of ash-slag will give the possibility to unlimited prolong of dumps operation period, to reduce their maintenance cost and to improve the environmental situation in areas of the dumps location. 

The issues of reliability and operation safety of power equipment, including hydraulic units of hydropower plants, are becoming more and more relevant with the increasing the service life. The long operation period and the individual characteristics of hydraulic units do not allow to apply outside the design lifetime the methodology for assessing the technical condition based only a simple extrapolation of the results of previous surveys. The integrated approach that combines application of modern diagnostic systems capabilities and achievements of computing technologies, the generalization of theoretical experience and the results of numerous experimental investigations using model and full-scale hydraulic units makes it possible to reliably and reasonably predict changes in the technical condition of hydraulic units, not allowing to reduce the reliability and safety below acceptable level. The material of this article was partially presented at the round table "Siberia Hydropower Development" at the VII Siberian energetic forum in 2016. 

Failures in energy systems can cause disconnection of power plant from power system for an extended period of time and subsequent autonomous start-up of power plant. The main difficulty of power plant start-up is associated with the launch of auxiliary motors from an independent power source, for instance, Black Start Diesel Generators (BSDG). Rated power of BSDG is selected in accordance to estimated loads determined by the sum of the capacities of all auxiliary loads of CCPP taking into account load factor and simultaneity factor. However, as the experience of operating of CCPP shows, the power of BSDG selected in this way does not always ensure a successful start-up of CCPP. Thus, selected power of BSDG for CCPP-450T unit of Kaliningradskaya Thermal Power Plant 2 didn’t bring CCPP-450T unit into operation during black out in 2011. In this regard, there is a need to conduct a research to determine the conditions for successful start-up of a CCPP unit. The essence of the problem lies in the determination of BSDG power capacity sufficient to provide an allowable voltage drop on the BSDG buses at the start of supplying auxiliary loads (with different auxiliary motors) of CCPP, as well as the determination of minimum cost of BSDG. A technique for determining BSDG power capacity sufficient to supply power to auxiliary loads at the start-up of CCPP has been developed. This technique takes into account transient processes in diesel engine and synchronous generator with excitation system when those trigger asynchronous motors and a thyristor starting devices. Moreover, the technique takes into account criteria for maintaining the minimum voltage level at BSDG buses for successful supplying of auxiliary loads. Performed research of CCPP-450T start-up process made it possible to determine the optimum power of BSDG and under various conditions for the start-up of auxiliary motors showed a direct simultaneous start-up of all auxiliary motors of CCPP unit with gas pressure in the pipeline above 2.3 MPa to be successful. However, start-up of auxiliary motors with gas pressure below 2.3 MPa (taking into account gas booster compressor) is possible only with sequentially developing start-up of auxiliary motors.

The article presents the results of numerical simulation of the influence of the temperature level in the zone of active combustion in the contents of nitrogen oxides and benz(a)pyrene in the combustion products of cracking of fuel oil for the boiler BKZ-420-140 NGM operating under boost. Obtained important characteristics of the combustion process for regulation of the specific release of toxic substances in flue gases. Processing of the obtained simulation results allowed us to obtain new mathematical correlations to calculate the concentration of benz(a)pyrene in exhaust gases in an indirect way based on the content of nitrogen oxides in the combustion products. Developed mathematical relationships can be used in the practice of commissioning actions for configuration of operating modes of boiler plants with minimal emissions of harmful compounds into the atmosphere. 

The dependency of dissolution of water in oil fraction from temperature and the number of organosulfurcompounds on the usage of model mixtures was studied. It is found, that the increase of concentration of organosulfurcompounds in model mixtures with high temperatures and electric field strength promotes the grouth of water solubility in them. Experimental researches have also shown that increase in concentration of organosulfurcompoundsand hygroscopicity of oil in conditions of his operation in power transformers is followed by growth of dielectric losses and decrease in electrical durability of oil.

In article calculation of an operating mode of power transformers for determination of optimum loading in case of which the efficiency of the transformer will reach the maximum value is provided, options of increase in efficiency of operation of power transformers of the industrial enterprises are also offered.

In this work the method of discrete ordinates is applied for the solution of the problem of transfering of radiation in a finite axisymmetric domain. Decisions for the conditions to model an absorbing medium are obtained. The results received with S2-, S4- approximations are given and their comparison with the experimental data of other scientists is carried out.

 

One of the most important properties of the electric power system is its observability. Ensuring observability is relevant not only for power flows and reliability indicators of power supply, but also for power quality indicators, in particular, the non-sinusoidal shape of the supply voltage. Increasingly, the use of elements of power electronics in intelligent power systems, and its application will grow in the future. This leads to the appearance of harmonic components of higher orders of current and voltage. The objects of the power system can be either sources or receivers of harmonics. In this regard, the actual task is to assess the impact of individual objects on the quality of electrical energy in the power system. The observability of Проблемы энергетики, 2017, том 19, № 7-8 86 power systems can be realized by the application of the phasor measurement units (PMU). In this paper, the authors suggest using a distributed system for monitoring the power quality by using the existing PMU infrastructure. This will allow for continuous monitoring of the level of harmonic oscillations in different sections of the power system. Especially this event should be used for isolated power supply systems.

 

Today important is the scientific study of solutions to the problem of participation of nuclear power plants, both existing and newly built, in the regulation of load schedules.However unacceptable a significant reduction of the capacity factor of nuclear power plants. Sufficient flexible of NPP equipment is the basis not only of the stability of large power systems in modes with violation of the frequency but also safety of the nuclear power plants, Проблемы энергетики, 2017, том 19, № 7-8 95 which would ensure cooling of the reactor during an accident.Therefore, the necessary capabilities of rapid discharges and increase in the load in large nuclear power plants, selected for emergency frequency control. High voltage variable frequency drives (VFD) of the main circulation pumps are able to provide the necessary reserve of growth power.Installation VFD of the MCPs are suitable for saving energy consumption in their drive on the partial regimes and to improve the stability of the neutron-physical active zone characteristics in variable modes.Using VFD of the MCPs can reduce increase pressures in the steam generators in the respective modes, restricting flow the coolant with a constant average temperature in the active zone of reactor, and therefore to reduce the energy consumption of the feed pump.

 

In paper the algorithm of registration of a signal of transition process which is given rise both by single-phase short circuit on the earth and is described by normal switching processes. Registration is performed by means of tension sensors which are established on an overhead power transmission line. The efficiency evaluation of the offered algorithm was made by comparison with the known signal detection algorithms in two parameters: in the maximum size of the relation a signal/hindrance and by the number of computing transactions. It is shown that the offered algorithm of the digital filter of the sensor occupies smaller resources of memory and requires smaller computing capacities of the microcontroller, and in too time allows to register reliably transitional process.

 

 

The device intended for measuring of principal thermoelectric parameters of the narrow-gap lead chalcogenide semiconductors (the Seebeck coefficient, electrical conductivity and thermal conductivity) have been created. The device created can be controlled by personal computer. In the temperature range from 270K to 500K the  correctness of values of the thermoelectric parameters measured by the device are following: thermal conductivity – ±5,7%; electrical conductivity – ±3,5%; the Seebeck coefficient – ±4%.

 

 

The article describes a Sensorless method for determining the position of the movable element electrical machines reciprocating action. The method is implemented on the basis of the data voltages of the windings and the results of measurements of parameters of electrical machines reciprocating action.

 

Developed a measuring complex for determining of LED lighting devices and the subsequent integral evaluation of their quality.

 

In article the possibilities of creation of effective power generating systems on the basis of the converted aircraft gas turbine engines such as NK-16ST are considered. Results of research of efficiency of the gas turbine engine such as NK-16ST with use of the turned gas generator cooled by the low-boiling working contour are provided.