Optimalizace napěťového meziobvodu frekvenčního měniče

Abstract

This thesis deals with the description, design and optimization of the DC voltage link of the voltage frequency inverter. In practice used for drive of asynchronous motors. At the beginning there is an issue, which concerns the effects of influence of ballast on the three-phase supply mains. Especially the formation of reactive power and harmonic distortion. The following are the different ways of power factor correction then limits of harmonic distortion. Descriptions of function of used circuits are performed by a fundamental schematic diagrams and basic mathematical relations for the expression of peripheral variables. Together with the analysis of the advantages and disadvantages of these circuits are drawn schematic diagrams of linking the intermediate voltage circuits with three phase diode bridge rectifier. The next point is the draft of increasing DC converter which has a function in DC voltage link. The values of the circuit elements were designed using PSpice simulation environment (in OrCAD) and specific values are based on calculations. In the last part is the measurement, which is performed with a commercial frequency inverter Siemens SINAMICS S120, connected to three-phase asynchronous motor.