Reliable power supply to power consuming units via isolated distributed generation: problematic issues and approaches to their solution

Abstract

The present study considers solutions to problematic issues concerning the integration of distributed generation facilities into the internal power supply network of power consuming units. The possibility of ensuring reliable power supply using verified models of generating plants and power consuming units is analysed along with a description of principles for the selection of control systems for generating plants. Full-scale measurements recording significant deviations in power quality indicators, were carried out. A total capacity of distributed generation facilities operating as a part of isolated energy districts is estimated at 8.5–9 GW. In addition, in the case of operation as a part of power systems, this capacity is equal to 13.5–14 GW. Therefore, the total capacity of these facilities is 22–23 GW or 9.5–10% of the total capacity of all generating facilities in Russia. The necessity of using verified mathematical models of generating plants, as well as main synchronous and asynchronous motors, along with the correct consideration of rotated mechanism types and real load factors, is substantiated. Principles for selecting the excitation systems of generating plants, as well as coordinating parameter settings for relay protection devices in generating plants and other elements in the internal power supply networks of power consuming units are considered. Recommendations regarding the permissibility of commutations and guaranteed correspondence between electric power quality indicators and regulatory requirements in island (autonomous) operating mode are provided. Thus, the need on the part of organizations that have necessary software systems and experience in conducting complex mode calculations to implement projects for integrating distributed generation facilities is substantiated. Here, the volume and complexity of calculations is higher than in the design of standard power plants and power supply systems.