Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
4 results
Search Results
Item Development of a New Hybrid Multilevel Inverter Using Modified Carrier SPWM Switching Strategy(Institute of Electrical and Electronics Engineers Inc., 2018) Venkataramanaiah, J.; Yellasiri, Y.; Panda, A.K.This letter presents a single-phase cascaded transformer based multilevel inverter with a modified carrier-based level shift sinusoidal pulse width modulation (LS-SPWM) technique. The developed topology has two bridges with individual low frequency transformers. The bridges can generate quasi-square waveform and pulse width modulated waveform independently and energized the two transformers whose secondary terminals are cascaded to attain 19-level output voltage waveform across the load. The anticipated configuration has the least number of components to reduce the cost and enhance the reliability of the converter for medium power applications with inbuilt isolation. Furthermore, this letter presents the most common LS-SPWM technique with a new carrier to enhance the fundamental magnitude and shifts the dominant harmonics into three times of the traditional strategy for the same modulation indices. The performance of the proposed topology is validated with experimental results. © 1986-2012 IEEE.Item A Fuzzy Logic Based Switching Methodology for a Cascaded H-Bridge Multi-Level Inverter(Institute of Electrical and Electronics Engineers Inc., 2019) Azeem, H.; Yellasiri, Y.; Jammala, V.; Shiva Naik, B.S.; Panda, A.K.In this letter, an unusual switching technique is implemented using a fuzzy logic approach. The proposed technique simplifies the conventional method by eliminating the traditional logic-gate design. The fuzzy logic pulse generator acts as a lookup table as well as a pulse generator. On the basis of the modulation index as input, controlled membership functions (MFs) and rules of the fuzzy logic controller open various possibilities of producing pulses directly. The proposed technique is evaluated on the cascaded multi-level inverter with symmetric and asymmetric operations using selective harmonic elimination pulsewidth modulation. MFs are designed on the basis of pre-calculated firing conditions for different modulation index values. Hardware verification is carried out to support the proposed switching technique. © 1986-2012 IEEE.Item A Novel Quadruple Boost Inverter With New Optimized Fuzzy-Based Switching Scheme(Institute of Electrical and Electronics Engineers Inc., 2024) Aditya, K.; Yellasiri, Y.; Shiva Naik, B.S.; Nageswar Rao, B.N.; Panda, A.K.This brief proposes a novel quadruple boost nine-level inverter (QB-NLI) and an optimized switching pattern using fuzzy logic controller. The suggested method simplifies the traditional approach by removing the conventional logic gate circuit design. The pulse signal generator and lookup table are both derived using a fuzzy logic pulse generator. Fuzzy logic controller (FLC) and Controlled membership functions (MFs) rules open numerous prospects for generating pulses based on the input as modulation index. The suggested technique is examined on the proposed QB-NLI topology using the selective harmonic elimination PWM method. MFs are created based on averaging Newton Rapson and quantizer firing angles for diverse modulation index (mi) values. The proposed QB-NLI structure comprises ten switches with one dc-voltage source and two capacitors. The proposed structure's circuit description, modes of operation, proper component selection, and a new fuzzy-based switching scheme are presented. Further, a discussion about the comparative analysis of the proposed switching technique with other switching techniques concerning THD and RMS voltages is presented. In addition to the simulation results, experimental tests are conducted under various load conditions on the built-in hardware prototype to evaluate the proposed QB-NLI structure and switching technique. © 2023 IEEE.Item A modified T-type multilevel inverter for renewable energy applications(Elsevier Ltd, 2024) Nageswar Rao, B.; Yellasiri, Y.; Shiva Naik, B.S.; Aditya, K.; Panda, A.K.The primary challenge in integrating renewable resources into grids using multilevel inverters (MLI) is the need for many separate DC sources and switching device counts. Transformer-based multilevel inverters (TMIs) have emerged to address this issue, aiming to minimize system components and boost source voltage with a single DC source. This research article introduces a novel TMI topology that utilizes only a single DC source and incorporates ten switches to produce good-quality load voltage with high magnitude. The proposed TMI offers several structural advantages, including self-galvanic isolation, reduced switching devices and uniform voltage levels across all turn ratios. Additionally, the TMI operates a switching method called pulse width modulation, which provides the gating pulses to all the power semiconductor devices in the proposed TMI. An experimental model has been created in a laboratory environment, and simulations are performed using the MATLAB/Simulink platform to assess the effectiveness of the suggested TMI. Furthermore, a comparison between the suggested TMI circuit and other recent TMI designs with similar characteristics is performed. This comparison is carried out to assess and validate the superior features of the proposed TMI over the alternative designs. © 2024 Elsevier B.V.