Journal Articles
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/19884
Browse
12 results
Search Results
Item A Fault Diagnosis and Postfault Reconfiguration Scheme for Interleaved Boost Converter in PV-Based System(Institute of Electrical and Electronics Engineers Inc., 2021) Ahmad, M.W.; Brahmendra Yadav Gorla, N.B.Y.; Malik, H.; Panda, S.K.To utilize the solar photovoltaic (PV) energy efficiently, dc-dc converters are widely used in both grid-connected and stand-alone systems. Among the various topologies, interleaved dc-dc boost converter offers the benefit of modularity, high power density, and high efficiency along with reduced input current ripple to the PV panel, thereby improving its power extraction efficiency. Open-circuit faults in any of the semiconductor switches of interleaved boost converter could lead to unequal loading on the healthy phases and increase in ripple current that reduces the extraction efficiency of the PV system. To address this issue, a new fault detection and localization scheme is proposed in this article. The proposed scheme utilizes the switching-frequency-based harmonic component for fault detection and localization. Once the fault is localized, a postfault restoration and control strategy is also proposed to ensure equal current sharing among the remaining healthy modules within their maximum current rating and minimize the input current ripple in the PV panel. Detailed simulations are carried out to show the effectiveness of the proposed approach. A laboratory prototype of the interleaved converter is built to validate the proposed approach and experimental test results are provided. © 1986-2012 IEEE.Item Noninvasive Model-Based Open-Circuit Switch Fault Detection of AC-Bypass Leg Switches in Transformerless PV Inverter(Institute of Electrical and Electronics Engineers Inc., 2021) Ahmad, M.W.; Brahmendra Yadav Gorla, N.B.Y.; Malik, H.; Panda, S.K.Transformerless inverters are being used for integrating photovoltaic (PV) sources into the grid. Highly efficient and reliable inverter concept (HERIC) inverter is one such topology, which is derived from an H-bridge by adding a bypass leg on the ac side using two back-to-back insulated gate bipolar transistors (IGBTs). Open-circuit fault in the bypass leg would result in conduction of current through antiparallel diodes of the main switches of the inverter, effectively making the inverter operate in bipolar mode. As a result of the fault, there would not be an issue of leakage current, and the operation would continue at the expense of increased conduction losses and dc-offset in the grid current. This article proposes an online noninvasive model-based technique to detect switch faults in the bypass leg of the HERIC inverter. The grid current at the peak of the carrier signal is predicted based on the measured grid current at the start of the zero states. By comparing the estimated and measured grid currents at the peak of the carrier signal, the faulty switch in the bypass leg is localized. Once the fault is localized, the inverter's modulation scheme is changed to conventional bipolar mode to improve the performance of the converter during the post-fault stage. A detailed simulation study is carried out to verify the effectiveness of the proposed approach. Experimental tests on the prototype converter show that the proposed algorithm can reliably detect the open-circuit fault in switches of the bypass leg, and once a fault is detected, the algorithm would change the modulation scheme to bipolar mode to minimize the inverter loss and dc-offset in the grid current. © 2013 IEEE.Item Development of wide area monitoring system for smart grid application(IOS Press BV, 2022) Malik, H.; Ahmad, M.W.; Alotaibi, M.A.; Almutairi, A.PMU can directly measure positive sequence voltage, phase and system frequency. In this paper, the design and implementation for optimum placement of PMU in power system network (PSN) has been performed using 5 different intelligent approaches at an emulation platform. Different case studies based on IEEE 7, 14 and 30 bus system have been performed and analyzed. In the studies, PMU device is used for the measurement of voltage and current magnitude as well as its phase and its performance has been compared with measured real signals of PSN. PMU measurement gives the accurate results and reliability to PSN. But PMUs are not economical, so PSN operator needs to install a minimum number of PMU in PSN so that system should be fully observable in a real-Time scenario. In this paper for optimal placement of PMU, five different intelligent methods have been analyzed for three different bus systems and obtained results are compared. For the further validation of selected PMUs for the PSN, a state estimation using WLS algorithm has been performed using conventional data and PMU data on IEEE14 and IEEE30 bus systems. The obtained results for voltage estimation error and phase estimation error with and without PMU data are compared. © 2022-IOS Press. All rights reserved.Item A New Single-Source Nine-Level Quadruple Boost Inverter (NQBI) for PV Application(Institute of Electrical and Electronics Engineers Inc., 2022) Singh, A.K.; Raushan, R.; Mandal, R.K.; Ahmad, M.W.Multi-level inverters (MLIs) with switched capacitors are becoming popular due to their utilization in AC high-voltage applications as well as in the field of renewable energy. To achieve the required magnitude of output voltage, the switched capacitor (SC) technique employs a lesser number of DC sources in accordance with the voltage across the capacitor. Designing an efficient high-gain MLI with fewer sources and switches needs a rigorous effort. This paper introduces a prototype of a nine-level quadruple boost inverter (NQBI) topology powered by one solar photo-voltaic source using fewer capacitors, switches, and diodes when compared to the other SC-MLIs topology. The suggested NQB inverter produces nine levels of voltage in its output by efficiently balancing the voltages of the two capacitors. The various SC-MLIs are compared in order to highlight the benefits and drawbacks of the proposed nine-level quadruple boost inverter (NQBI) topology. To validate the efficacy of the proposed solar photovoltaic based NQBI without grid connection, detailed experimental results are presented in a laboratory setting under various test conditions. © 2013 IEEE.Item Design and Implementation of Different Drive Topologies for Control of Induction Motor for Electric Vehicle Application(River Publishers, 2022) Husain, M.A.; Rajput, R.; Gupta, M.K.; Tabrez, M.; Ahmad, M.W.; Ilahi Bakhsh, F.I.To improve driving range in Electric vehicles (EV), parallel-series connection of battery cells is a necessity. Supressing the circulating current in the battery board of parallel connected battery strings helps improve the lifespan of the batteries. This study presents a comparison of the requirements of parallel strings of batteries in three different popular topologies for open end winding induction motor (IM) drives in EV. The topologies analyzed are a 3-phase voltage source inverter (VSI), a Dual fed inverter and three single-phase HBridge VSIs. These converters are modulated using Space vector pulse width modulation (SVPWM) as it has better performance compared to Sine PWM. MATLAB-Simulink models are developed for the converter topologies. The simulation results show that the three single-phase inverter topology feeding the drive is the best alternative when compared on the basis of battery requirement and switch loss. Moreover, each H-bridge inverter (in the three single-phase inverter topology) can be used as charger and the problem of circulating current during charging will also be least as compared to other schemes. © 2022 River Publishers.Item A Review of Open-Circuit Switch Fault Diagnostic Methods for Neutral Point Clamped Inverter(MDPI, 2022) Mullali Kunnontakath Puthiyapurayil, M.R.; Nadir Nasirudeen, M.; Saywan, Y.A.; Ahmad, M.W.; Malik, H.Due to numerous advantages, a neutral point clamped (NPC) inverter is a preferred choice for high-power applications and renewable technology. The reliability of the NPC inverter is a major concerning factor during the assessment of system performance as power semiconductor switches are vulnerable to abnormal conditions. Open-circuit (OC) switch faults are not as dangerous as short circuit (SC) faults but eventually have enough potential to cause cascaded failure to other components in the system and thus need to be supervised carefully. The OC faults result in a distortion of voltage and current signals in the NPC converter. Based on these signals, over the past few years, many efforts have been made to identify and localize the OC switch fault to the switch level in the NPC topology. In this paper, a review of different OC switch fault diagnostic methods is provided. Starting from the NPC inverter operation under healthy and faulty conditions, the various possible and unavailable switching states along with the deviation in pole voltage under different switch fault conditions is discussed. Then, based on the approach used for system-based fault detection, the OC fault detection methods are classified. The various OC methods are further discussed on the basis of signal, i.e., current, voltage or a combination of both signals used as a signature for fault detection. Emphasis is given to the principle involved, diagnostic variables utilized, the implementation approach and the diagnostic time required. Finally, the approaches are tabulated so as to provide a quick reference for NPC fault diagnostics. © 2022 by the authors.Item Bat Optimization Model for Electric Vehicle Route Optimization Under Time-of-Use Electricity Pricing(Springer, 2023) Vani, B.; Kishan, D.; Ahmad, M.W.; Naresh Kumar Reddy, B.In the framework of fuel reduction and energy conservation, the electric vehicles (EV’s) has been identified as a promising option in contrast to fuel-driven vehicles. EV’s battery limits to require visiting a greater number of times to the recharging stations, which must be viewed as in the route planning to keep away from inefficient vehicle routes with lengthy diversions. These problems have to consider, we propose an Efficient Electric Vehicle Route Optimization with Time-of-Use Electricity Pricing using Bat algorithm. Which can reduce the used vehicles as well as electricity-cost and total travel distance. Additionally, functional model and collective models are used to minimize the objectives: distance and cost. The computational assessment in light of the notable benchmarking test instances exhibits, proposed optimization algorithm electricity cost conservation on average 12.17% with Learnable Partheno-Genetic Algorithm (Yang et al. in IEEE Trans Smart Grid 6:657–666, 2015) 8.45% with VNS/TS Algorithm (Lin et al. in Trans Res Part-C 130:103285, 2021) and 5.15% with Mixed Integer Programming model (Ham and Park in IEEE Access 9:37220–37228, 2021). © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Item A Novel Single Source Bridgeless Nine-Level Switched-Capacitor-Based Quadruple Boost Inverter With Reduced Voltage Stress(Institute of Electrical and Electronics Engineers Inc., 2024) Kumar, D.; Raushan, R.; Ahmad, M.W.; Dutta, S.The attractiveness of switched capacitor multilevel inverters (SCMLIs) stems from their ability to operate without transformers, providing voltage-boosting capabilities, inherent capacitors' voltage balancing ability, and reduced electromagnetic interference. Recent developments in SCMLI structures make it a compelling choice among various converters for diverse applications. The evolution of these topologies is primarily influenced by factors such as the number of output voltage levels, overall voltage gain, and the simultaneous reduction of component counts and stresses on devices. To address these issues further, a novel bridgeless common neutral switched capacitor multilevel inverter has been proposed in this article. The maximum voltage stress on the devices is just half of the peak output voltage, and the total standing voltage is also lower in this inverter. It has quadruple voltage gain and inherent voltage balancing of the switched capacitors. Additionally, it can operate under various loads and modulation indexes. Moreover, the proposed inverter's leakage current can be almost zero due to the presence of the common ground (CG) feature. The nearest level pulse width control technique has been implemented to operate the proposed inverter. Comparative analysis was carried out to show the advantages of the inverter. Further, a hardware prototype of the experimental setup has been developed, and results have been analyzed and discussed to strengthen the performance of the proposed inverter. © 2013 IEEE.Item A Reduced Component Count Self-Balance Quadruple Boost Seventeen-Level Switched Capacitor Inverter(Institute of Electrical and Electronics Engineers Inc., 2024) Ahmed, S.; Raushan, R.; Ahmad, M.W.A switched capacitor multilevel inverter (SCMLI) enables high-quality output voltage waveforms for various industrial and renewable energy applications. SCMLI uses a combination of capacitors and switches to generate multiple voltage levels from a single dc source, thereby reducing the overall cost and size of the system. This article proposes a novel configuration of a 17-level SCMLI. The proposed converter can boost four times the input voltage by exploiting the series-parallel connection of capacitors with the dc voltage source. With simple pulsewidth modulated (PWM) control, the capacitor voltages are inherently balanced under different loading conditions. Furthermore, for 11 switches, only seven independent switching signals are required. Loss analysis reveals that the proposed SCMLI has significantly reduced conduction losses, capacitor ripple voltage, voltage stress, and cost function (CF) when compared with other topologies available in the literature. Finally, the simulation results are obtained at different loads and modulation indexes. The results are experimentally validated with a scaled-down laboratory prototype. © 2024 Institute of Electrical and Electronics Engineers Inc.. All rights reserved.Item An Inductorless Triple Boost 13-Level Switched Capacitor Inverter with Reduced Ripple Current(Institute of Electrical and Electronics Engineers Inc., 2024) Ahmed, M.S.; Raushan, R.; Ahmad, M.W.Switched capacitor (SC) multilevel inverter (SCMLI) is a promising alternative to traditional voltage source inverters for industrial and renewable energy applications. In SCMLI, capacitors are used in a specific sequence during charging and discharging either in parallel or series with the source for level generation. During the charging period of the capacitor, a large ripple current is generated. This ripple may cause an increase in the peak current and ripple voltage of the capacitors. The reliability and life expectancy of the inverter can be severely affected by this ripple current of the capacitor. This article proposes an inductorless self-balance single-phase 13-level inverter with triple boosting capability. It aims to reduce the ripple current in both the source and capacitors by arranging the switching sequence in a particular fashion to implement a partial charging technique in the capacitors. Furthermore, it results in better efficiency and reduced current stress without the need for any source inductance or a complicated control algorithm. The performance of the proposed inverter is verified through its laboratory prototype under dynamic load conditions and varying modulation indexes. © 1986-2012 IEEE.