Transformer-Based Power Conversion System with Synchronous Adjustment of Modulated Inverters

• Main Author: Oleschuk V.
• Format: Article
• Language: English
• Published: Academy of Sciences of Moldova 2018-04-01
• Series: Problems of the Regional Energetics
• Subjects: inverter; a; ac drive
• Online Access: http://journal.ie.asm.md/assets/files/10_01_36_2018.pdf
• ISSN: 1857-0070

Purpose of this work – dissemination of specialized schemes of space-vector modulation for synchronous adjustment of multi-inverter system with power transformer. Multi-winding power transformer systems are between perspective topologies of power conversion systems. Parameters and characteristics of transformer-based ac drives depend largely on the used methods and techniques of control and modulation. These medium-power and high-power systems are characterized by relatively low switching frequency of inverters. Modification of algorithms of space-vector modulation for transformer-based system with several converters allows providing an improvement of spectral composition of winding voltages of the system. Set of control functions includes in this case special correlations for continuous determination of parameters of control signals for this triple-inverter system. Simulation of modulation processes in this structure of system has been executed for different modes of its operation. Analysis of harmonic composition of basic voltage waveforms has been executed. Areas of the rational use of continuous and discontinuous versions of modified algorithms of modulation have been established. It has been found that for the analyzed transformer-based system it is reasonable to use algorithms of continuous modulation at lower and medium output frequencies of the system, and at higher output frequencies, the use of algorithms of discontinuous modulation makes it possible to provide the better spectral composition of the winding voltage. Advanced harmonic composition of spectra of the corresponding voltages allows providing increase of efficiency of operation of this topology of power conversion systems.