Sanjeevikumar Padmanaban

Bio: Sanjeevikumar Padmanaban is an academic researcher from Aarhus University. The author has contributed to research in topics: Photovoltaic system & Boost converter. The author has an hindex of 34, co-authored 367 publications receiving 5244 citations. Previous affiliations of Sanjeevikumar Padmanaban include Sathyabama University & National Institute of Technology, Puducherry.

Optimisation of hybrid renewable energy system using iterative filter selection approach

Abstract: This study presents a hybrid renewable energy system that yields minimum total project cost and maximum reliability. The system is in modular configuration consisting of photovoltaic (PV) array, wind turbine, battery storage, AC load and a dump load. Also, the minimisation of unutilised surplus power is taken into consideration as one of the design objectives. In this study, a new technique named iterative filter selection approach is used in designing the hybrid PV-wind turbine-battery system to obtain the best acceptable solution while considering all the design objectives. The system is then justified by comparing with iterative-Pareto-fuzzy and particle swarm optimisation techniques. The technique is found to be superior in terms of total project cost with satisfaction to the load demand. The method is simulated using MATLAB and the results are presented in the study with proper discussion.

4Nx Non-Isolated and Non-Inverting hybrid Interleaved Multilevel Boost Converter based on VLSIm Cell and Cockcroft Walton voltage multiplier for renewable energy applications

Abstract: In this treatise, 4Nx hybrid Non Inverting & Non Isolated (NI-NI) DC-DC interleaved multi-level boost converter (4Nx IMBC) for renewable energy applications is proposed. The proposed 4Nx IMBC is derived by coalescing the feature of 2Nx DC-DC Interleaved Multi-level Boost Converter (2Nx IMBC), voltage-lift-switched-inductor-modified (VLSIm Cell) and Cockcroft Walton (CW) voltage multipliers. The 4Nx converter provides 4N times more conversion voltage ratio compared to conventional boost converter where N denotes the number of output stages of the 4Nx IMBC. To make renewable energy sources applicable at user end its DC voltage magnitude needs to be incremented with high conversion. Existing and recently proposed DC-DC converter are not sufficiently expert to employ practically, because of stability issues, high duty cycle and high ripple in the output. To overcome the conversion ratio problem isolated boost DC-DC converter are in use but it makes circuitry bulky and costly because of transformer and several coupled inductors. The converter topology proposed in this treatise reduces the output ripple and overcome the problem mentioned above without exploiting extreme values of duty cycle or transformers. Simulations results of proposed circuitry are presented which verify the analysis, function, working modes & feasibility of proposed circuitry converter.

Design and Implementation of Multilevel Inverters for Electric Vehicles

Abstract: The efficient and compact design of multilevel inverters (MLI) motivates in various applications such as solar PV and electric vehicles (EV). This paper proposes a 53-Level multilevel inverter topology based on a switched capacitor (SC) approach. The number of levels of MLI is designed based on the cascade connection of the number of SC cells. The SC cells are cascaded for implementing 17 and 33 levels of the output voltage. The proposed structure is straightforward and easy to implement for the higher levels. As the number of active switches is less, the driver circuits are reduced. This reduces the device count, cost, and size of the MLI. The solar panels, along with a perturb and observe (P&O) algorithm, provide a stable DC voltage and is boosted over the DC link voltage using a single input and multi-output converter (SIMO). The proposed inverters are tested experimentally under dynamic load variations with sudden load disturbances. This represents an electric vehicle moving on various road conditions. A detailed comparison is made in terms of switches count, gate driver boards, sources count, the number of diodes and capacitor count, and component count factor. For the 17-level, 33-level, and 53-level MLI, simulation results are verified with experimental results, and total harmonic distortion (THD) is observed to be the same and is lower than 5% which is under IEEE standards. A hardware prototype is implemented in the laboratory and verified experimentally under dynamic load variations, whereas the simulations are done in MATLAB/Simulink.

An Original Hybrid Multilevel DC-AC Converter Using Single-Double Source Unit for Medium Voltage Applications: Hardware Implementation and Investigation

Abstract: In this article, an original hybrid multilevel DC-AC converter configurations are proposed by using single-double source unit for medium voltage applications. The proposed topologies are derived by hybridization of single and double source units with polarity changer and cascaded with full-bridge converter for medium and high voltage applications. Two different hybrid topologies presented and each topology configured for both symmetric and asymmetric method. The proposed hybrid topologies compared with the conventional cascaded H-bridge converter (CHB), and the best topologies recommended for medium voltage applications. The comparison in terms of the number of switches, gate driver circuits, maximum blocking voltage by switches and total peak inverse voltages of switches presented. The proposed topologies require a small installation area and low cost. The validity of the proposed hybrid converter structures is verified by simulation using MATLAB/Simulink and hardware results. The simulation and hardware results show a good agreement with the theoretical approach.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Exoelectrogenic bacteria that power microbial fuel cells

Abstract: The use of microbial fuel cells to generate electrical current is increasingly being seen as a viable source of renewable energy production In this Progress article, Bruce Logan highlights recent advances in our understanding of the mechanisms used by exoelectrogenic bacteria to generate electrical current and the important factors to consider in microbial fuel cell design There has been an increase in recent years in the number of reports of microorganisms that can generate electrical current in microbial fuel cells Although many new strains have been identified, few strains individually produce power densities as high as strains from mixed communities Enriched anodic biofilms have generated power densities as high as 69 W per m2 (projected anode area), and therefore are approaching theoretical limits To understand bacterial versatility in mechanisms used for current generation, this Progress article explores the underlying reasons for exocellular electron transfer, including cellular respiration and possible cell–cell communication