Rajasekar Selvamuthukumaran

Bio: Rajasekar Selvamuthukumaran is an academic researcher from Power Grid Corporation of India. The author has contributed to research in topics: Formal verification & Power electronics. The author has an hindex of 6, co-authored 8 publications receiving 416 citations. Previous affiliations of Rajasekar Selvamuthukumaran include Techno India.

Recent advances and challenges of fuel cell based power system architectures and control – A review

Abstract: Renewable energy generation is rapidly growing in the power sector industry and widely used for two categories: grid connected and standalone system. This paper gives the insights about fuel cell operation and application of various power electronics systems. The fuel cell voltage decreases bit by bit with expansion in current because of losses associated with fuel cell. It is difficult in handling large rated fuel cell based power system without regulating mechanism. The issue connected with fuel based structural planning and the arrangements are widely investigated for all sorts of utilization. In order to improve the reliability of fuel cell based power system, the integration of energy storage system and advanced research methods are focused in this paper. The control algorithms of power architecture for the couple of well-known applications are discussed. Additionally, the paper addresses the suitable processor utilized as a part of the energy unit application on the premise of fuel cell characteristics. In this paper, the challenges to improve the dynamics of controller in fuel cell based applications are mentioned.

Formal validation of supervisory energy management systems for microgrids

Abstract: An energy management system of a microgrid (MG) has several basic objectives; e.g. to maximize the utilization of renewable energy resources (RES), to protect the internal components from overloading, and to ensure that the MG operates reliably under any operating conditions. Although many control techniques are available in the literature to monitor and control the energy flows among distributed RES in MGs, formal verification of those techniques was not proposed yet. The emphasis of this paper is to design and validate energy management system for a MG which consists of a solar photovoltaic (PV) array, a pair of battery energy storage systems (BESes), a diesel generator (DG) and a load (LD). The physics and dynamics of the MG are defined as energy flow invariants and the designed behaviours are abstracted, modelled and validated in this work. Therefore, we have considered an invariant based flow technique to manage the energy flow in an MG. The results are validated and verified with UPPAAL, a powerful industrial tool which is commonly used to verify the correctness of real-time systems like supervisory controllers, communication protocols and others.

Supervisory Energy-Management Systems for Microgrids: Modeling and Formal Verification

Abstract: This article presents the modeling and verification of supervisory energy-management systems (EMSs) for microgrids using timed automata (TA) and a formal verification approach. The EMS plays an essential role in managing the power flow among different components in the microgrid system for its safe and reliable operation. The modeling of the EMS is based on predefined invariants with allowable and nonallowable operating modes, which are the conditions that do not change over time. The failure of invariants could have severe effects on microgrid system functionality, which highlights the importance of verification during the initial stage of EMS design. Conventional approaches, such as simulation and/or experimental verification, require manual checking and skilled professional knowledge to check EMS design correctness. Also, there may be a corner case that could lead to system failure that goes unidentified by manual analysis.

Single-phase seven-level stack multicell converter using level shifting SPWM technique

Abstract: This paper presents a single-phase seven-level stack multicell converter (SMC) which provides a viable solution for multilevel converter. Conventional cascaded multilevel inverter (MLI) removes the drawbacks of clamping diodes and clamping capacitors topologies. However, in a cascaded MLI number of voltage source and power switches increases as the number of level increases. The main advantage of single-phase SMC converter is only two DC sources are needed for any number of levels. Level shifting SPWM technique has been incorporated to achieve gate pulses, in which carrier wave of 20kHz is compared with 50Hz sinusoidal reference wave at a modulation index of 1 and 0.9. Total harmonic distortion (THD) for SMC converter is achieved at 1.55% and 5.26% with and without filter respectively. The seven-level SMC topology is simulated in MATLAB/SIMULINK and simulation results are provided to verify the performance.

A Comprehensive Study of Key Electric Vehicle (EV) Components, Technologies, Challenges, Impacts, and Future Direction of Development

Abstract: Electric vehicles (EV), including Battery Electric Vehicle (BEV), Hybrid Electric Vehicle (HEV), Plug-in Hybrid Electric Vehicle (PHEV), Fuel Cell Electric Vehicle (FCEV), are becoming more commonplace in the transportation sector in recent times. As the present trend suggests, this mode of transport is likely to replace internal combustion engine (ICE) vehicles in the near future. Each of the main EV components has a number of technologies that are currently in use or can become prominent in the future. EVs can cause significant impacts on the environment, power system, and other related sectors. The present power system could face huge instabilities with enough EV penetration, but with proper management and coordination, EVs can be turned into a major contributor to the successful implementation of the smart grid concept. There are possibilities of immense environmental benefits as well, as the EVs can extensively reduce the greenhouse gas emissions produced by the transportation sector. However, there are some major obstacles for EVs to overcome before totally replacing ICE vehicles. This paper is focused on reviewing all the useful data available on EV configurations, battery energy sources, electrical machines, charging techniques, optimization techniques, impacts, trends, and possible directions of future developments. Its objective is to provide an overall picture of the current EV technology and ways of future development to assist in future researches in this sector.

Nanomaterials for solid oxide fuel cells: A review

Abstract: Nanotechnology is utilized well in the development and improvement of the performance in Solid Oxide Fuel Cells (SOFCs). The high operating temperature of SOFCs (700–900 °C) has resulted in serious demerits regarding their overall performance and durability. Therefore, the operating temperature has been reduced to an intermediate temperature range of approximately 400–700 °C which improved performance and, subsequently, commercialized SOFCs as portable power sources. However, at reduced temperature, challenges such as an increase in internal resistance of the fuel cell components arise. Although, this may not be as serious as problems encountered at high temperature, it still significantly affects the performance of SOFCs. This review paper addresses the work of researchers in the application of nanotechnology in fabricating SOFCs through distinct methods. These methods have successfully omitted or at least reduced the internal resistance and showed considerable improvement in power density of the SOFCs at reduced temperatures.

Recent Progress on Zinc-Ion Rechargeable Batteries

Abstract: The increasing demands for environmentally friendly grid-scale electric energy storage devices with high energy density and low cost have stimulated the rapid development of various energy storage systems, due to the environmental pollution and energy crisis caused by traditional energy storage technologies. As one of the new and most promising alternative energy storage technologies, zinc-ion rechargeable batteries have recently received much attention owing to their high abundance of zinc in natural resources, intrinsic safety, and cost effectiveness, when compared with the popular, but unsafe and expensive lithium-ion batteries. In particular, the use of mild aqueous electrolytes in zinc-ion batteries (ZIBs) demonstrates high potential for portable electronic applications and large-scale energy storage systems. Moreover, the development of superior electrolyte operating at either high temperature or subzero condition is crucial for practical applications of ZIBs in harsh environments, such as aerospace, airplanes, or submarines. However, there are still many existing challenges that need to be resolved. This paper presents a timely review on recent progresses and challenges in various cathode materials and electrolytes (aqueous, organic, and solid-state electrolytes) in ZIBs. Design and synthesis of zinc-based anode materials and separators are also briefly discussed.

On-Board Microgrids for the More Electric Aircraft—Technology Review

Abstract: This paper presents an overview of technology related to on-board microgrids for the more electric aircraft. All aircraft use an isolated system, where security of supply and power density represents the main requirements. Different distribution systems (ac and dc) and voltage levels coexist, and power converters have the central role in connecting them with high reliability and high power density. Ensuring the safety of supply with a limited redundancy is one of the targets of the system design since it allows increasing the power density. This main challenge is often tackled with proper load management and advanced control strategies, as highlighted in this paper.