Smart grids (SGs), as an emerging grid modernization concept, is spreading across diverse research areas for revolutionizing power systems. SGs realize new key concepts with intelligent technologies, maximizing achieved objectives and addressing critical issues that are limited in conventional grids. The SG modernization is more noticeable at the distribution grid level. Thus, the transformation of the traditional distribution network (DN) into an intelligent one, is a vital dimension of SG research. Since future DNs are expected to be interconnected in nature and operation, hence traditional planning methods and tools may no longer be applicable. In this paper, the smart distribution network (SDN) concept under the SG paradigm, has presented and reviewed from the planning perspective. Also, developments in the SDN planning process have been surveyed on the basis of SG package (SGP). The package presents a SDN planning foundation via major SG-enabling technologies (SGTF), anticipated functionalities (SGAF), new consumption models (MDC) as potential SDN candidates, associated policies and pilot projects and multi-objective planning (MOP) as a real-world optimization problem. In addition, the need for an aggregated SDN planning model has also been highlighted. The paper discusses recent notable related works, implementation activities, various issues/challenges and potential future research directions; all aiming at SDN planning.

Owing to the economic, social, and political problems in the expansion of transmission infrastructure, novel transmission topologies are in demand to efficiently utilize the existing infrastructure. On the other hand, there is a tremendous increase in wind power generation around the globe. One of the main challenges hindering the penetration of large-scale wind power generation is the network congestion due to limited network capacity. To address these two issues, this study develops a co-optimized optimal transmission switching (OTS) and dynamic line rating (DLR) model to optimize system resources by mitigating network congestion and maximizing wind power accommodation. This new concept of exploiting the inherent flexibility in transmission network is named as flexible transmission dynamic line rating (FTDLR), which deploys OTS in coordination with DLR as a control tool to utilize existing assets. A two-stage stochastic unit commitment framework is used to deploy the proposed FTDLR model, which is used to dynamically increase the line capacity based on the meteorological parameters and at the same time optimally select candidate lines to be switched off from the network. A comprehensive analysis is performed to characterize the FTDLR performance on system operation cost, network congestion, and wind power curtailment. The proposed FTDLR model is further tested as a part of contingency analysis where both generator failure and transmission line outages are considered. Test results performed on the IEEE 24-bus network demonstrate that by using FTDLR, the service operator could substantially reduce system dispatch cost, improve wind power accommodation, and relieve network congestion. The scalability and feasibility of the FTDLR optimization problem is validated on the larger network of the IEEE 118-bus system.

Depleting fossil fuels and pressing global warming challenges are wreaking havoc towards the sustainable future of mankind. To cater these alarming issues, renewable energy sources and alternate means of energy harnessing have been investigated rigorously for last several decades. Similarly, transportation sector has also seen paramount reforms with hybrid vehicles now seen as potential competitors to conventional internal combustion vehicles (ICEV). The major challenge hybrid vehicles face today include slothful battery charging rates and less electric driving range. The range can be extended by optimal power sharing between engine and electric motors and by optimally sizing the engine thus lowering the weight on the chassis. Ultrafast DC charging is concurrently pondered upon to ramp up the sluggish battery charging rates. This paper is compiled with the perspective to give readers a comprehensive and concise review about the literature conducted on the architecture of different variants of hybrid vehicles till date with more focus on power sharing between engine and motor under different driving conditions in different types of hybrid vehicles.

All power converters, including dual-active-bridge (DAB) DC-DC converter, cannot sustain a consistently high-efficiency performance over a wide range of operating conditions, and reconfiguration of operation mode represents a viable solution to this fundamental problem. To meet this challenge, a resonant-type three-phase DAB (3p-DAB) converter incorporating a three-phase reconfigurable resonant network (3p-RRN) has been proposed in this article. The proposed converter can operate either as a 3p-DAB resonant immittance converter (3p-DABRIC) or a 3p-DAB series resonant converter (3p-DABSRC) to enhance its efficiency performance over a wide range of voltage conversion ratio and output power levels. In addition, the proposed converter offers the flexibility to operate with unity power factor, full-range zero-voltage switching (ZVS) and enhanced light-load efficiency under varying operating conditions by appropriate selection of the converter's operation mode. Based on a careful loss analysis and verification of the loss model by experimental measurements, it has been found that under wide range variations in voltage conversion ratio and output power levels, 3p-DABSRC delivers a more superior efficiency performance at low to medium power levels, whereas 3p-DABRIC generally achieves a higher efficiency at high power levels, and thus combination of both operation modes leads to an overall wide range high-efficiency performance.