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Future transportation will replace the current mechanical combustible engines with chargeable electric vehicles (EVs). The DC-Dc boost converter is an essential part of such systems that not only helps to generate the required level but also helps to regulate the load voltage. In conventional boost converter topologies, their gain, switching losses, and high voltage stress across switches are the main reason for limiting the output power. Coupled inductor-based isolated converters increase the system weight and cost. Therefore, in this paper, a transformerless adjustable gain and non-isolated DC-DC boost converter with multi-port flexible power supply, reduced switch voltage stress, and considerable good range efficiency is proposed. The proposed converter is tested with the 100 W resistive load to test the desired characteristics. [ABSTRACT FROM AUTHOR]

Abstract In this paper, New asymmetric cascaded half H bridge multilevel inverter MLI is proposed. It is driven from the conventional asymmetric cascaded half H Bridge multilevel inverter. Thus, the proposed topology inherits its simplicity, flexibility and modularity in both construction and control. By proper choice of the input DC sources values and interconnection, proposed topology can eliminate the need for polarity generation circuit which normally associated with the cascaded half H-bridge. Therefore, reduces number of switches that require high blocking voltage. The selective harmonic elimination SHE method is applied to generate switching pattern to eliminate harmonics inherently associated with MLI. The proposed topology switching pattern naturally reduces component's voltage stress, switching losses and finally decrees MLI size and cost. Mathematical expressions and analysis have been driven as well as comparison with other topologies. The validity of the proposed topology is verified with Matlab/Simulink model and then a prototype is built and experimental results are presented. [ABSTRACT FROM AUTHOR]

A special cascaded configuration of asymmetric multilevel inverter is presented in this paper. This configuration cancels the redundancy of output voltage steps and maximizes the number of levels in the output voltage. This structure is built by using series connected stages, which minimize the number of semiconductor switches, gate drive arrangements, occupying area, and cost. It is a modular type inverter model and the number of voltage levels can be increased by adding new stages without changing the previous connection. Space vector modulation has been applied as the control strategy. A prototype of the proposed inverter topology has been built in the laboratory. The attached hardware results indicate the accuracy of the proposed model, which include the topology as well as the control technique. [ABSTRACT FROM AUTHOR]

This paper presents a single-phase five-level inverter controlled by two novel pulse width modulation (PWM) switching techniques. The proposed PWM techniques are designed based on minimum switching power loss and minimum total harmonic distortion (THD). In a single-phase five-level inverter employing six switches, the first proposed PWM technique requires four switches to operate at switching frequency and two other switches to operate at line frequency. The second proposed PWM technique requires only two switches to operate at switching frequency and the rest of the switches to operate at line frequency. Compared with conventional PWM techniques for single-phase five-level inverters, the proposed PWM techniques offer high efficiency and low harmonic components in the output voltage. The validity of the proposed PWM switching techniques in controlling single-phase five-level inverters to regulate load voltage is verified experimentally using a 100 V, 500 W laboratory prototype controlled by dspace 1103. [ABSTRACT FROM AUTHOR]

This study presents a new design and implementation of a three-phase hybrid multilevel inverter (MLI) using space vector modulation. The proposed MLI consists of a reduced number of dc sources and switches to minimise the control complexity. The developed topology consists of two stages: main stage and auxiliary stage. The main stage is a conventional three-phase inverter with one high-voltage input dc source and six switches. The auxiliary stages contain three individual cells. Each cell consists of two switches and one low-voltage input dc source. This topology is a modular type and without changing the previous connection it can be extended for more number of output voltage levels by adding certain number of auxiliary stages. A space vector modulation control technique has been utilised in order to generate different switching sequences. The special feature of the proposed system is its capability to maximise the number of voltage levels using a reduced number of isolated dc voltage sources and electronic switches. A prototype has been developed and tested for various modulation indexes to verify the control technique and performance of the topology. Experimental results validate the simulation results and the experimental results show a good similarity with the simulation results. [ABSTRACT FROM AUTHOR]