This paper combines quasi-Z-source into a typical five-level inverter, which includes two dc voltage sources, two quasi-Z-sources and five switching devices. In this structure, the output voltage amplitude is not limited to dc voltage source and it can be increased by quasi-Z-source. Besides, due to nature of Z-source families, this new structure is reliable and higher efficiency. Also, in this...

This paper presents an analysis of the sliding mode control (SMC) method applied to a single-phase grid-connected voltage source inverter (VSI) with L and LCL filters. First, simulation results were presented for filter, then, after some adjustments, same theory was VSI active damping. To improve obtained SMC control, we adopted hyperbolic tangent function explicit establishment modulation inde...

This study presents different technologies and topologies of medium-voltage (MV) drives available on the market. The paper describes the advantages and disadvantages of each configuration and the impact in the quality of energy in the mains and motor sides when using them is also analyzed. Technical requirements and practical considerations for end users and system designers are identified for ...

This paper presents a hybrid modulation technique consisting of singe-reference six-pulsemodulation (SRSPM) for front-end dc/dc converter and 33% modulation for three-phase inverter. Employing proposed novel SRSPM to control front-end dc/dc converter, high frequency (HF) pulsating dc voltage waveform is produced, which is equivalent to six-pulse output at 6× line frequency (rectified 6-pulse ou...

This paper describes the mathematical modelling of selfexcited induction generators (SEIGs) with are improved electronic load controller (IELC) for microhydel applications supplying variety of loads. In small hydro plants, governor unit of turbine can be eliminated using IELC, which is simple and cost effective. The improved electronic load controller is a combination of a three-phase insulated...

This paper presents a method to control both the dc boost and the ac output voltage of Z-source inverter using neural network controllers. The capacitor voltage of Z-source network has been controlled linearly in order to improve the transient response of the dc boost control of the Z-source inverter. The peak value of the line to line ac output voltage is used to control and keep the ac output...

This paper describes role of UPQC as applied to a 3P4W system to improve PQ. The Forth wire of 3P4W system is developed by means of neutral of series transformer. Neutral current which flows through neutral terminal of transformer is removed with the help of 4 leg voltage source inverter (VSI) topology for shunt part. The series transformer neutral will have 0 potential in all conditions of ope...

Recent advances in power electronic technology have seen the development of a range of converter based power compensation systems which have the potential to improve supply quality and increase line utilisation in weak distribution networks at relatively low cost. However, the interaction of these devices with the supply network has not been well documented. In this paper we investigate the ste...

The Dynamic Voltage Restorer (DVR) is a commercially available, popular device to eliminate voltage sags and swells in the distribution lines. Its basic function is to inject the voltage difference (difference between the pre-sag and sag voltage) to the power line and maintains the pre-sag voltage condition in the load side. The efficiency of the DVR depends on the performance of the efficiency...