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Showing 1 to 19 of 19 for “"Voltage Source Inverters"”.
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Design of LCL-filters for grid-connected voltage source inverters
… over conventional L-filters for grid-connected voltage source inverters (VSI) due to their superior harmonic attenuation, smaller filter size and weight. The LCL-filter design process is complex and takes an iterative approach due to the coherence between the filter parameters and design …
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Control Strategies for High Power Four-Leg Voltage Source Inverters
… that negatively influence the performance of the Voltage Source Inverter (VSI). Ideal, infinitely stiff power systems are uninfluenced by loading conditions; however, realistic systems, with finite output impedances, encounter stability issues, unbalanced phase voltage, and harmonic distortion. …
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Development of pulse-width-modulation techniques for multi-phase and multi-leg voltage source inverters
… with supply coming from a single multi-phase voltage source inverter (VSI). Various pulse width modulation (PWM) schemes have been developed for multi-phase machines with concentrated and distributed windings, utilising both carrier-based PWM and space vector PWM (SVPWM) approaches. However, …
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Mitigation Of Electromagnetic Interference In Pulse Width Modulated Voltage Source Inverters And Communication Enhancement In Power Lines
… involves the operation of pulse width modulated inverters. Because of the high switching rate of the semiconductor switches harmonics are generated in the output voltage and current of the inverter. These harmonics result in propagation of electromagnetic noise in the power electronic system. …
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Analysis and Comparison of Space Vector Modulation Schemes for Three-Leg and Four-Leg Voltage Source Inverters
… have been analyzed for three-leg and four-leg voltage source inverters. The analysis is performed with respect to a) switching losses, b) total harmonic distortion, c) peak-to-peak ripple in the line current and d) the ease of digital implementation. The analysis is performed over the entire …
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Development of control techniques for direct AC‐AC matrix converter fed multiphase multi‐motor drive system
… first one consists of a number of three‐phase voltage source inverters connected in parallel to a common DC link, each inverter feeding a three‐phase AC motor. This configuration allows independent control of all machines by means of their own three‐phase voltage source inverters (VSIs). …
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Derivation of Parabolic Current Control with High Precision, Fast Convergence and Extended Voltage Control Application
… topic in modern power electronics system. For voltage source inverters, current control loop ensures the waveform quality at steady state and the fast response at transient state. To improve the current control performance, quite a few nonlinear control strategies have been presented and one …
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High Power Density and Overcurrent Protection Challenges in the Design of a Three-Phase Voltage Source Inverter for Motor Drive Applications
The voltage source inverter (VSI) is certainly the most popular topology used in dc to ac power conversion. Virtually every commercial electric motor is driven by a VSI. There is a need for smaller and more efficient drives in high performance applications that is dictating unprecedented power …
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Optimized Harmonic Stepped-Waveform for Multilevel Inverter
The concept of multilevel voltage source inverters and their modulation topologies are described. The concept of the Optimized Harmonic Stepped-Waveform (OHSW) technique for a multilevel inverter is presented. By applying this concept, specific harmonics can be eliminated, and the output voltage …
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Medium voltage petrochemical drives : soft start and adjustable speed systems
Medium voltage synchronous machines are used for large petrochemical compressor motor drives (>13 MW) at high application voltages (e.g. +-11 kV). Limited research exists on the application of Voltage Source Inverters (VSIs) for these petrochemical loads. An application concept is described where …
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Multilevel inverters for renewable energy systems
Voltage source inverters have become widely used in the last decade primarily due to the fact that the dangers and limitations of relying on fossil fuel based power generation have been seen and the long term effects felt especially with regards to climate change. Policies and targets have been …
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Modeling and Control of Parallel Three-Phase PWM Converters
… converters include three-phase boost rectifiers, voltage source inverters, buck rectifiers and current source inverters. The averaging of the parallel converters is performed based on a generic functional switching unit, which is called a phase leg in boost rectifiers and voltage source inverters, …
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COMMON MODE VOLTAGE ELIMINATION IN THREE-PHASE FOUR-LEG INVERTERS UTILIZING PULSE DENSITY MODULATION
… negatively affects power electronics to include voltage source inverters. Typically, CM EMI reduction is achieved through passive measures such as CM chokes and passive filters. This thesis research explores removing the need for these passive devices in three-phase, four-leg grid-following …
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Parameter study of boost inverter topologies for high voltage gain
… that is beyond human control. The conventional Z-source network and switch inductor Z- source inverter is located between the DC voltage source and the inverter, which boosts the DC voltage. Traditional inverters such as voltage source inverters and current source inverters have few inherent …
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Soft-switching techniques for high-power PWM converters
… functions with minimum increase of device voltage/current stresses and converter circulating energy, and thus have advantages over conventional techniques in efficiency, power density, reliability, and cost of power converters. The improved zero-current transition (ZCT) converters achieve …
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Optimal vertical plane booster guidance including pitch dynamics
… functions with minimum increase of device voltage/current stresses and converter circulating energy, and thus have advantages over conventional techniques in efficiency, power density, reliability, and cost of power converters. The improved zero-current transition (ZCT) converters achieve …
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A novel concept of series connected multi-phase, multi-motor drive systems
… first one consists of a number of three-phase voltage source inverters (VSI) connected in parallel to a common DC link, each inverter feeding a three-phase AC motor. This configuration allows independent control of all machines by means of their own three-phase VSIs. The second method comprises …
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A Brushless DC Motor Drive Without a DC Link Capacitor
… based on the position of the rotor by using voltage source inverters that consist of a rectifier, a DC link capacitor and an inverter. In comparison to the other electronic components in the circuit, the DC link capacitor has a limited lifetime, which is severely dependent on the ambient …
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Modelling, Design and Implementation of D-Q Control in Single-Phase Grid-Connected Inverters for Photovoltaic Systems used in Domestic Dwellings.
This thesis focuses on the single-phase voltage-source inverter for use in photovoltaic (PV) electricity generating systems in both stand-alone and grid-tied applications. In many cases, developments in single-phase PV systems have followed developments in three-phase systems. Time-variant systems …