Research On Harmonic Energy Extraction And Utilization Technology In Power System

Along with the wide application of the power electronic device in the power system, the power grid is being polluted increasingly by harmonic, and influences the quality of power supply. At present, the mostly-used method is to adopt the active and passive restraint way of harmonic,which aims at effectively restraining harmonic pollution of the grid, and seriously affects the standards of safe operation. Harmonic is harmful to the power grid, and seriously affects the safe operation of the power grid, but harmonic itself is a form of energy. If the restraint of harmonic is converted into the use of harmonic electricity energy, the economic benefits from utilizing harmonic energy will compensate the relevant equipment economic investment, and make operation and maintenance also become the beneficial links in the development of cyclic economy. Therefore, the topic research on the harmonic extraction and utilization of the harmonic power has very significant realistic meaning.This paper firstly introduces some concepts and definitions about harmonic, as well as some processing methods and research status about harmonic, at the same time, the fundamental magnetic flux compensation and tuning harmonic technology that apply to this technology are analyzed and studied. On this basis, a novel technology of extracting and using harmonic energy in power grid based on the principle of fundamental magnetic flux compensation and tuning filter technology is proposed and analyzed through the three-winding transformer in this paper. The novel device makes the transformer primary side and the RC circuit form tuned circuit through the rational design of the three windings parameter of transformer, so that the harmonic energy of power grid flow into the transformer primary side. According to the principle of fundamental magnetic flux compensation, the tertiary winding of the transformer eliminates the fundamental capacitive reactive power in harmonic energy, so the secondary winding of the transformer extracts non-funda-mental harmonic energy, by frequency conversion device, which coverts into the directly available fundamental frequency power. Finally, the topology structure of circuit of the tuning harmonic technology is constructed, this structure and its parameter is also designed and analyzed. The simulation model of single and three circuits are built and its steady-state characteristics are simulated and analyzed by MATLAB6.5 in the paper, the simulation results proves the accuracy and feasibility of the design.