The Research On SVG++Applied In Large-scale Coal Enterprises

With the rapid development of coal mining mechanization, the substantial increase ofmining production significantly increases the total capacity of the electrical equipment,amplies stand-alone power, and lengthens power supply distance. Especially theapplication of some impact load and nonlinear load leads to a series of power qualityproblems including the decline of power factor, voltage fluctuations and current waveformdistortion. So it is particularly important to carry out reactive power compensation andharmonic control for the coal mining enterprises. Traditional reactive power compensationdevices are a long time needed for response, and its regulation characteristic is poor. While,SVG(Static Var Generator) employs power electronics inverter technology and utilizesGate-Turn-Off Thyristor—GTO、 Insulated-Gate Bipolar Transistor—IGBT fullcontrollability devices. So it is a short time needed for response, at the same time, it canachieve bidirectional continuous compensation. What is more, compensation effect isgood. But its capacity is limited by the device itself and the cost.This paper proposes SVG++dynamic reactive power and filtering comprehensivecompensation programme (dynamic reactive power and filtering comprehensivecompensation equipment composed by SVG and other passive compensation or filteringdevices). Which is composed by SVG suitable for high voltage system and high voltageautomatic reactive power and voltage regulating device HVC. SVG++takes advantage ofrapid response and controllability of SVG to restrain voltage flicker and harmonics.Furthermore, SVG++makes use of HVC’s passive high capacity to achieve fixed loadcompensation and the suppression of some harmonics. So the entire device has continuouscompensation function within a certain compensation capacity range. All technicalindicators can meet requirements in field conditions including dynamic characteristic,compensation capacity, cost effectiveness, harmonics suppression, safety and reliabilityetc.First of all, this paper analyzes the principle of SVG, then establishs transient andsteady-state mathematical model of SVG. Secondly, it compares p qandip iq reactive current detection method based on the theory of instantaneous reactive, discussingtwo current control modes consist of straightforward current and indirect current controlmode. So the proposed of reactive current detection method and control modes of SVG inthis paper is obtained. Finally, the program is designed for a specific coal miningenterprise of renovation project and it is employed in this renovation project. This paperbuilds simulation model of SVG++, then verifies together feasibility and validity ofSVG++program through measured waveform comparison of Matlab/Simulink and dataanalysis.