Recently, switched inductor and switched capacitor techniques in DC-DC converter are recommended to achieve high voltage by using the principle of parallel charging and series discharging of reactive elements. It is noteworthy that four diodes, one high voltage rating switch, two inductors are required to design classical Switched Inductor Boost Converter (classical SIBC). Moreover, in classical SIBC, the switch voltage stress is equal to the output voltage. In this paper, modified SIBC (mSIBC) is proposed with reduced voltage stress across active switches. The proposed mSIBC configuration is transformer-less and simply derived by replacing the one diode of the classical switched inductor structure with an active switch. As a result, mSIBC required low voltage rating active switches, since the total output voltage is shared into two active switches. Moreover, the proposed mSIBC required the same number of components compared to the classical SIBC. The Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM) analysis, the effect of non-idealities on voltage gain, design methodology, and comparison of mSIBC are presented in detail. The operation and performance of the designed 500W mSIBC are validated through simulation and experimental work.

The paper proposes a new structure of SEPIC with high voltage gain for renewable energy applications. The proposed circuit is designed by amalgamating the conventional SEPIC with a boosting module. Therefore, the converter benefits from various advantages that the SEPIC converter has such as continuous input current. Also, high voltage gain and input current continuity makes the presented converter suitable for renewable energy sources. The Modified SEPIC Converter (MSC) provides higher voltage gain as compared to conventional SEPIC and recently addressed converters with a single controlled switch. The analysis of voltage gain in Continuous Current Mode (CCM) and Discontinuous Current Mode (DCM) modes is analyzed by considering the non-idealities of the semiconductor devices and passive components. The selection of semiconductor devices depending on the voltage-current rating is presented along with designing of reactive components. The numerical simulation and experimental work carried out and obtained results prove the feasibility of the MSC concept and theoretical analysis.

Based on the concept of switched-capacitor based multilevel inverter topology, a new structure for a boost multilevel inverter topology has been recommended in this paper. The proposed topology uses 11 unidirectional switches with a single switched capacitor unit to synthesize nine-level output voltage waveform. Apart from the twice voltage gain, self-voltage balancing of capacitor voltage without any auxiliary method along with reduced voltage stress has been the main advantages of this topology. The merits of proposed topology have been analyzed through various comparison parameters including component counts, voltage stresses, cost and efficiency with a maximum value of 98.3%, together with the integration of switched capacitors into the topology following recent development. Phase disposition pulse width modulation (PD-PWM) technique and nearest level control PWM (NLC-PWM) have been used for the control of switches. Different simulation and hardware results with different operating conditions are included in the paper to demonstrate the performance of the proposed topology.

High gain DC/DC converters with high efficiency are needed in DC microgrid owed to the low voltage of power sources e.g. photovoltaic-cell and fuel-cell. This paper proposed a new high gain Double-Duty-Triple-Mode (DDTM) converter for DC-Microgrid applications. Proposed DDTM converter operates in three modes to achieve higher voltage gain without utilizing transformer, coupled inductor, voltage multiplier, and multiple voltage lifting techniques e.g. triple, quadruple voltage lift. The modes of operation of the converter are controlled through three switches with two distinct duty ratios (double duty) to achieve wide range duty ratio. The operating principle, voltage gain analysis, efficiency analysis of the proposed converter are discussed in detail and to show its benefits comparison is provided with the existing high gain converters. The boundary operating condition for Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM) is presented. The prototype of proposed converters with 500W power is implemented in the laboratory and experimentally investigated which validate the performance and feasibility of the proposed converter. Due to double duty control, the proposed converter can be controlled in different ways and the thorough discussion on controlling of the converter is provided as a future scope.

Energy security is one of the most crucial factor in the development of any nation. Interconnections among different power system networks are made to lower the overall price of power generation as well as enhance the reliability and the security of electric power supply. Different types of interconnection technologies are employed, such as AC interconnections, DC interconnections, synchronous interconnections, and asynchronous interconnections. It is necessary to control the power flow between the interconnected electric power networks. The power flow controllers are used to (i) enhance the operational flexibility and controllability of the electric power system networks, (ii) improve the system stability and (iii) accomplish better utilization of existing power transmission systems. These controllers can be built using power electronic devices, electromechanical devices or the hybrid of these devices. In this paper, control techniques for power system networks are discussed. It includes both centralized and decentralized control techniques for power system networks. This paper also presents a comprehensive review of HVDC interconnections, asynchronous AC interconnections, synchronous AC interconnections and different types of power flow controllers used in these interconnections. Moreover, some important and multivariable flexible AC transmission system (FACTS) devices such as UPFC and IPFC are also discussed with their merits and limitations. Finally, a new asynchronous AC link called flexible asynchronous AC link (FASAL) system is also described in detail. At last, a summary of the comparative analysis of power system link and power flow controllers is given based on recent publications. More than 400 research articles and papers on the topic of power transfer control are covered in this review and appended for a quick reference.