Scientific Journal of KubSAU

Analysis of scientific literature has shown a promising direction in energy saving and in increasing of efficiency of power supplies remote from external networks in Russia is the application of solar photovoltaic power plants. The level of solar radiation on the territory of Russia varies widely from 810 kWh/m2 per year in remote Northern areas to 1,400 kWh/m2 per year in southern areas. We have revealed their main advantages and disadvantages of solar photovoltaic power plants, as well as the purpose, basic features, features selection and operation of inverters and batteries. We have also given a generalized block diagram of three types of solar photovoltaic power plants: autonomous, standby, network. The peculiarities of their work have been presented. To improve the reliability of operation of solar power plants we need to design them according to the modular principle. Modular aggregation has to be applied for stand-alone inverters, where the input and output filters, power electronic circuit and system voltage regulation and protection represent the functional module elements. It is possible to increase significantly the reliability of autonomous inverters and solar PV systems in the complex, using one-phase and three-phase transformers with rotating magnetic field in their design. The advantages and the disadvantages, the peculiarities of the solar PV plants discussed in the article will allow to develop their structural and circuit designs with improved maintenance characteristics in the future

In the article, the general concepts and the maintenance of total, technical and economic resource of solar power are revealed. The advantages of solar power in comparison with other kinds of energy are resulted. We have shown, that currently the method of direct photoelectric transformation is one of priority directions of reception of solar electric power in the world. It is because it provides the maximal ecological cleanliness of transformation, an opportunity of reception of energy practically in any area, significant service life and small expenses for service. The structure and features of work of solar photo-electric installations were listed as well. The schemes of using photo cells and their voltage and amperes characteristics, lacks of solar photo-electric stations are resulted, basic of which are: high cost of photo-electric converters and presence of accumulators, and we have also offered recommendations on their effective use. The basic analytical expressions for definition of economic efficiency of solar photo-electric stations are resulted. The considered features of the work, the basic characteristics and the parameters of solar photo-electric stations which will allow to increase the efficiency of predesign works on development of the combined (hybrid) stations, generating electric and thermal energy, received from solar radiation

The article analyzes the main characteristics of the electricity generators to use them as a part of small hydroelectric power plants. It is shown, that contactless asynchronous generators in comparison with synchronous generators and DC generators have improved their operational and technical characteristics, and above all, their reliability and performance efficiency. We have shown graphic dependences of the cost and the weight of power generators. It is proposed using direct frequency converter as a stabilizer of parameters of asynchronous generator of electricity, used as a source of electricity for small hydropower plants. The article explains the features of the work and the choice of parameters for generators, working together with the direct frequency converters. The authors have revealed some aspects of the work of direct frequency converters with natural commutation and with adjustable phase angle, including their advantages and disadvantages. The article also presents block diagrams for small hydroelectric power plants, made with the help of asynchronous generators and direct frequency converters

Widespread in autonomous systems, including uninterrupted power supply systems, there are power static (electronic) convertors: rectifiers and inverters, used to match the parameters of the electric power source and the load; they also have a function of voltage stabilizers. Important question is the calculation of key performance criteria at the design stage: power losses, efficiency, reliability, weight and size (for electrical transport systems). The article discusses the methodology of the simplified calculation of the basic criteria of efficiency of inverters and rectifiers. There are schematic electrical diagrams of power rectifiers and inverters, and the basic analytical expression for a simplified calculation of the basic criteria of efficiency of the converters, including their output filters. Each year, we improve the technical characteristics of the probes using new element base, allowing reducing the level of electromagnetic interference generated by power electronic devices. We have also shown perspective directions of the development of power converter technology by using one-phase and threephase transformers with rotating magnetic field in their creation (therefore we increase reliability of operation and efficiency). A promising direction is the construction of converters and autonomous systems in a modular complex, where (in addition to increased system reliability) we simplify its operation, including service