111,928 research outputs found
Algorithms, Schemes and Techniques of Space-Vector Modulation for Dual-Inverter Systems with Symmetrical Multilevel Phase Voltage
No full textBasic schemes of synchronized space-vector-based pulsewidth modulation (PWM) have been applied for control of dual-inverter fed open-end winding motor drive supplied by two dc-sources with non-equal voltages. It has been shown, that algorithms of synchronized PWM provide continuous phase voltage symmetry for any ratio (integral or fractional) between the switching and fundamental frequencies of two inverters, and also for any ratio between voltages of two dc-sources of dual-inverter systems. MATLAB-based simulations illustrate behavior of dual-inverter systems with synchronized PWM. Spectra of multilevel phase voltage of open-end winding drives with both continuous and discontinuous schemes of synchronized PWM do not contain even harmonics and sub-harmonics during the whole control range, including the zone of overmodulation, which is especially important for the medium-power and high-power systems
Analysis of Operation of Symmetrical Dual Three-Phase Converters with Hybrid Schemes of Synchronised PWM
No full text
Dual Neutral-Point-Clamped Converters with Synchronized PWM for Photovoltaic Installations
No full textAbstract - A novel method of synchronized pulsewidth modulation (PWM) has been modified and disseminated for control of dual (cascaded) neutral-point-clamped converters, supplied by two insulated strings of photovoltaic panels and connected to grid by a three-phase transformer with open-end windings on primary side. Specialized strategy and scheme of synchronized PWM, applied for control of dual converters, provide in this case: a) continuous phase voltage synchronization and required voltage regulation in the system by the corresponding control of modulation indices of the two converters; b) elimination of undesirable common-mode voltages both in each inverter and in the load, and c) an improvement of effectiveness of operation of the system due to flexible control of switching frequencies of inverters as function of DC voltages of photovoltaic panels. Simulations give a behavior of dual-converter-based photovoltaic system with three basic versions of synchronized PWM
Combined synchronized PWM for dual neutral-clamped converters for asymmetrical split-phase traction drive
No full textThe paper presents results of analysis of operation of asymmetrical split-phase (six-phase) electric vehicle drive on the base of two neutral-clamped converters, controlled by combined schemes of synchronized pulsewidth modulation (PWM), providing both common-mode voltage cancellation and continuous synchronization of the output voltage of inverters during the whole control diapason. Simulations give behaviour of the systems with synchronized space-vector modulation. Phase voltages of dual three-phase (split-phase) drives with synchronized PWM have symmetry during the whole control range including overmodulation, and their spectra do not contain even harmonics and subharmonics, which is especially important for high power/current system
Simplifying Approach for Analysis of Space-Vector PWM for Three-Phase and Multiphase Converters
No full textOvermodulation control of five-phase inverters with full DC-bus voltage utilization
No full textThe paper presents novel strategy of synchronous control of five-phase inverters in the zone of overmodulation. New time-domain-based approach for analysis and synthesis of algorithms of synchronized pulsewidth modulation (PWM) allows providing smooth three-stage transition from a linear modulation region to the ten-step control mode of five-phase systems with space-vector modulation. Simulations give the behavior of five-phase inverters with synchronized PWM during overmodulation. The spectra of the phase-to-neutral voltage of five-phase power conversion systems with algorithms of synchronized PWM do not contain even harmonics and sub-harmonics in the zone of overmodulation, which is especially important for the high power/high current application
Synchronous control of six-phase traction drive with two DC links
No full textNovel method of synchronized pulsewidth modulation (PWM) has been applied for a dual source fed multiphase drive using an asymmetrical six-phase induction machine. Detail description of modulation processes in hybrid six-phase system controlled by two inverters with continuous and discontinuous schemes of synchronized PWM and supplied by two separate DC sources with different voltages, has been presented. Special attention has been given to analysis of performance of the six-phase drive with synchronized PWM in the zone of overmodulation. Simulations give a behavior of six-phase drives controlled by two inverters with synchronized PWM, based on space-vector approach. It provides minimum number of switchings and minimal switching losses in the systems. The spectra of the phase voltage of the six-phase drives with algorithms of synchronized PWM do not contain even harmonics and sub-harmonics during the whole control range, which is especially important for the high power/current applications
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