This study presents space vector-based quasi-two-level operation of a diode-clamped multilevel inverter which improves dc link utilisation and output voltage quality, and avoids the dc link capacitor voltage balancing problem experienced with standard multilevel operation. Beside a review of quasi-two-level operation and the capacitor voltage balancing method, the study presents a detailed disc...

A power electronic converters are becoming more and more popular for medium voltage & high power applications. To overcome the limitation of semiconductors current and voltage ratings in high power applications, multilevel inverter is often considered an effective solution. In addition, stepped waveform in the output of multilevel inverter has better harmonic spectrum than 2-level inverter in l...

In this paper, the operation principle of the Z-source inverter is analysed in detail. According to the characteristics of allowed short–shrougt zero state in the Z-source inverter, SPWM control method of the Zsource inverter is obtained by inserting fixed short–shrougt zero state into zero state of SPWM. It is simple and easily implemented in practice. However, in inductive load condition the ...

Grid connected inverters play a crucial role in generating energy to be fed to the grid. A filter is commonly used to suppress the switching frequency harmonics produced by the inverter, this being passive, and either an L- or LCL-filter. The latter is smaller in size compared to the L-filter. But choosing the optimal values of the LCL-filter is challenging due to resonance, which can affect st...

Digital control techniques for Boost Converter and PWM Inverter which have potential application for power transmission system. The study is done in the field of inverter topologies, which is used to interface a wind energy module to the power grid/load. The boost converter and inverter are developed with focus on low cost, high reliability and massproduction. The switching strategy to control ...

Space Vector Based Pulse Density Modulated scheme for multilevel inverter is proposed in this paper. A two level and three level inverters with three different DC input voltages are used to produce 18 stepped output sinusoidal voltage. First order sigma delta modulator is used to obtain Pulse Density Modulation. The vector space is divided into 18 segments for spatial quantization. Sixty degree...

This paper proposes the Modified Switched Inductor Quasi Z Source Inverter (MSL-QZSI) for extracting maximum solar power generation. The Z source inverter uses LC impedance network to couple the main converter circuit to the power source, which provides the boosting of input voltage. It is not possible in traditional voltage-source inverter (VSI) and current-source inverter (CSI). The proposed ...

This paper deals with the performance analysis of three phase induction motor drive fed by a PWM voltage source inverter. The PWM method, which involves the modulation of conventional sinusoidal reference signal and a triangular carrier is used here to produce pulse width modulated output only for under modulation index. This paper work deals mainly with the performance analysis of three phase ...

The three-level Neutral Point Clamped (NPC) inverter has become matured and widely used topology in high-power medium-voltage applications due to several advantages associated with it as compared to other available multilevel topologies. This paper presents a brief review on operation of threelevel NPC inverter. Different modulation strategies used in NPC inverter is also discussed. The problem...

The steady state analytical performance of a line commutated inverter fed three phase synchronous motor under variable speed condition is presented. The firing pulses for six silicon-controlled-rectifiers of the three phase inverter are generated by the control circuit in proper sequence with the help of synchronizing signal derived from the induced electromotive force of the synchronous machin...