The Department of Electrical and Electronics Engineering proudly announces that the invention “Zero Voltage Switching Full-bridge Converter for Multiple LED Lighting Loads with Reduced Switch Current” with Application number: 202241076718 has been granted to Dr Ramanjaneya Reddy, Assistant Professor, Dr Tousif Khan Nizami, Associate Professor, and Ms Aswini Patakamoori, PhD Scholar in the Indian Patent Office Journal.

The research focuses on creating an energy-efficient power supply for LED lights, especially in areas that use a DC electricity system. The team has designed a system that can power multiple LED lights from a single unit, saving energy and cost. This system works at a very high efficiency of about 97.5%, which means very little energy is wasted as heat.

The special design uses a method called “soft switching,” which helps the internal parts of the system turn on and off with less stress, reducing heat and improving lifespan. It also needs fewer parts for each light, making it simpler, more reliable, and cheaper to produce. Additionally, the system allows the lights to be dimmed easily using a basic on-off control method, giving flexibility in brightness as needed.

Abstract

A 110 W soft-switched full-bridge multiple load LED driver is designed for DC-grid applications, achieving a high efficiency of 97.52%. The full-bridge configuration ensures that the switches carry minimal current, reducing conduction losses, and offers zero-voltage switching, significantly lowering switching losses. The reduced component count per lamp simplifies the design, enhances reliability, and reduces overall system costs. Additionally, the driver supports PWM-based dimming through simple on-off control, offering flexibility in illumination levels.

Practical Implementation/ Social Implications of the Research

The developed 110 W soft-switched full-bridge multiple-load LED driver is a highly efficient and scalable solution tailored for DC-grid applications, particularly those integrated with solar and battery-based energy systems. Operating at an impressive efficiency of 97.52% ensures minimal energy loss. This technology promotes sustainable development by enabling cleaner energy usage and reducing carbon emissions. Its simple, cost-effective design makes advanced lighting more accessible, especially in low-income or remote communities. Additionally, the ability to dim lights easily helps conserve energy further and allows users to adapt lighting to different needs, enhancing comfort and minimising waste.

Future Research Plans

To design more efficient, adaptable, and sustainable LED driver circuits,

1. Extending soft-switching techniques to automotive, industrial, and smart lighting systems for broader applications.
2. Incorporating digital control strategies for intelligent dimming, adaptive power regulation, and real-time performance monitoring.
3. Exploring advanced semiconductor materials, such as Gallium Nitride (GaN) and Silicon Carbide (SiC), to enhance switching performance and thermal stability. Integration of energy harvesting techniques to create self-sustaining LED driver systems powered by renewable sources such as solar energy.

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The patent titled “A System to Control Dc-Dc Buck Power Converter And A Method Thereof” by research scholar K Mounika Nagabushanam, and Assistant Professors, Dr Somesh Vinayak Tewari, and Dr Tarkeshwar Mahto with application no: 202441098288 presents an innovative approach to managing power conversion in renewable energy systems extending its applications in electric vehicles and microgrids, highlighting the importance of robust power control in advancing sustainable energy technologies.

Abstract

The work disclosed a system to control DC-DC buck power converter and a method thereof. The system comprises a photovoltaic (PV) panel, a first DC-DC buck converter for voltage step-down, and a battery for energy storage. A bidirectional DC-DC converter manages power flow between the battery and the source bus, while a second bidirectional converter exchanges power with the AC grid. The load bus integrates a second DC-DC buck converter to regulate power for constant power loads and resistive loads. Switching components like IGBTs controlled through PWM signals, ensure precise power control. Inductive and capacitive elements stabilize voltage, filter ripples, and reduce noise. The system supports adaptive power distribution and robust load handling, ensuring efficient energy management.

Explanation in layperson’s terms

Passivity-based control (PBC) is a control technique applied to buck converters within renewable energy systems to maintain stability and efficiency despite varying input conditions. Buck converters are essential for stepping down fluctuating voltage outputs from renewable sources, such as solar panels, to a consistent level suitable for storage or direct use. In solar power systems, PBC is used to manage the voltage conversion from solar panels to batteries or the grid. It stabilizes the voltage output, ensuring efficient battery charging and smooth integration with the electrical grid. PBC’s application in renewable energy systems demonstrates its critical role in advancing sustainable energy technologies, providing a reliable and efficient power supply.

Practical and Social Implications

The proposed control can be used in Electric Vehicle, Microgrid applications to stabilize voltage under load variations.

Future research plans

Future research plan is to work on the testing of proposed control with high level DC-DC converters

Dr Satyavir Singh, Assistant Professor from the Department of Electrical and Electronics Engineering and his PhD scholar, Mr Tasadeek Hassan Dar, have published a groundbreaking research paper titled “Advanced integration of bidirectional long short-term memory neural networks and innovative extended Kalman filter for state of charge estimation of lithium-ion battery.” The research that revolves around establishing technology for intelligent management of battery systems and their sustainability for longer life has been published in the Q1 journal, Journal of Power Sources, having an impact factor of 8.1.

Further to their research, the team will continue to work on robust techniques to BMS in the future.

Abstract

The state of charge (SoC) of a battery is a crucial monitoring indicator for battery management systems and it helps to assess how much further an electric vehicle can travel. This work proposes a novel approach for predicting battery SoC by developing a closed-loop system that integrates a bidirectional long short-term memory neural network with an innovative algorithm- extended Kalman filter. A second-order equivalent circuit model is selected, and its parameters are computed using the variational and logistic map cuckoo search approach.

Further, an Extended Kalman filter is combined with an innovation algorithm to update process noise in real-time, and a bidirectional long short-term memory neural network takes the input from the Extended Kalman filter and gives the compensated error value for the final SoC estimation. 75% of dynamic stress test data from the Extended Kalman filter is used for training purposes, remaining data sets are used for testing purposes. The addressed algorithm is validated by evaluating its performance in comparison to individual algorithms and various combined approaches. Empirical analysis demonstrates that the proposed model achieves a root mean square error of 0.11% and mean absolute error of 0.1% positioning it as a valuable tool for battery management systems.

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Electronic Vehicles (EVs) are a key element of carbon emission reduction strategies and pivotal to contributing to sustainable development. Operating solely on electrical energy, eliminating the need for petrol or diesel, EVs leave a significantly reduced carbon footprint compared to fossil fuel-powered vehicles. Underscoring the impact of EVs on the environment, advanced research is conducted to improve the efficacy and reliability of EVs.

On this note, a research team from the Department of Electrical and Electronics Engineering – Dr Tarkeshwar Mahto, Dr Somesh Vinayak Tewari, Dr Ramanjaneya Reddy and PhD scholar Ms K Mounika Nagabushanam has published a paper titled “High Gain Bi-directional KY converter for low power EV Applications” in the Q1 journal Energy having an Impact Factor of 9. Their research work focuses on the development of a bi-directional DC-DC converter that can be used in EVs for integration of battery to traction motor.

Abstract

In electric vehicles (EVs), the type of electric motor and converter technology have a significant impact on regulating the operational characteristics of the vehicle. Therefore, in this work, the modified bi-directional KY converter (BKYC) is proposed for EV applications. The main contributions of the proposed converter are high step-up/step-down conversion gain, bi-directional power flow, simplified control structure, continuous current, common ground, low volume, and high efficiency. An inductor on either side of the converter ensures continuous current flow and passive components are arranged to operate in series to offer high step-up/step-down conversion. The charging and discharging operations, steady-state analysis, and design process of the proposed converter are discussed in detail and compared with similar bi-directional converter topologies. Further, the efficiency analysis of the proposed converter is presented, and it was found that the efficacy is 95.51% in the charging operation and 96.52% in the discharging operation. The simulations are carried out using MATLAB/Simulink environment. Further, a prototype of a modified bi-directional KY converter is implemented with a TMS320F28335 processor and validated with theoretical and simulation counterparts.

Explanation of the Research in Layperson’s Terms

Electric vehicles (EVs) are built with traction motors, charging circuits, energy storage devices, and lighting systems. Each runs at a different voltage and has a different power level. Various power electronic converters are used to integrate the individual components of an electric vehicle. An electric vehicle (EV) runs primarily on battery power, which can be obtained from on-board charging or charging stations. The battery has a voltage range of 24 to 48 volts. The traction motor, coupled to a DC link bus with a voltage range of 400V to 600V, needs to receive this energy. Consequently, it is necessary to integrate a power converter to raise the voltage from lower voltage batteries to a higher voltage DC link. Additionally, energy lost during motor running can be used to charge batteries to improve the efficiency of the electric vehicle. Therefore, a separate power electronic converter is required for the power flow from the motor to the battery. The primary output of our study is the development of a bi-directional DC-DC converter that facilitates power flow from the battery to the motor and motor to the battery with the necessary voltage gains while maintaining improved efficiency and low cost.

The main challenges in EV technology are battery deterioration due to frequent charging and discharging and the volume of the power converter. The research team plans –

• To work on the noise reduction methods that are brought on by regeneration action
• To work on various control techniques to keep the DC link voltage of the propulsion system constant

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The increasing demand for sustainable energy solutions has led to the development of hybrid energy systems that integrate renewable sources like solar photovoltaic (PV) systems and fuel cells (FC).  The practical applications of the research in sectors such as electric vehicles and residential power systems, contribute to a more reliable and sustainable energy future contributing to a more reliable and sustainable future.

Abstract of the research.

This paper introduces novel high-gain tertiary port boost converter (HGTPBC) designed for hybrid energy sources such as solar photovoltaic (PV) and fuel cells (FC). The converter is employed with dual input sources by facilitating modular converters and accomplishes a high step-up voltage gain by virtue of a voltage multiplier in a DC microgrid, where the prosumers can have an islanded operation. The proposed topology allows home appliances to be powered by multiple energy source without the need for a large storage unit. Key features include continuous input current, reduced normalized voltage stress on switches, expandability for multiple input sources and independent source control. The independent control facilitates the standalone operation with single source during source failure or absence. To evaluate the converter performance, a thorough steady-state analysis, both with and without consideration of nonidealities is carried out. Detailed comparisons with existing converter topologies highlight the advantages of the proposed converter. Moreover, the loss distribution and efficiency analysis of proposed converter are presented and found to be 91.59% efficiency at rated power. Theoretical aspects are validated through hardware testing on a 100W laboratory prototype.

Explanation of the Research in layperson’s terms.

The proposed converter is a 100W DC-DC converter topology used in hybrid energy systems applications and electric vehicular applications in DC microgrid. The converter can accept two sources like fuel cell and solar PV system to supply the load and even can be extended for a greater number of sources. Thus, it is suitable for various applications of traction vehicles, household electrifications etc. It exhibits a lower switch stress and higher step-up conversion gain.

Practical Implementation and Social implications

The features include high step-up conversion gain, independent control possible, reduced normalised switch voltage stress. And flexible operation based on PV availability. It is most suitable for electric vehicles, Unmanned ariel vehicles, and hybrid energy systems etc. It improves the reliability of the renewable energy source by the incorporation of the second fixed source, fuel cell. It can be used in various on-grid and off-grid applications like home, hospitals, offices, and educational institutions, especially where source reliability is necessary. The major advantage is the reduction in the size of the source due to higher step-up gain and ease of control between the sources.

Future Research Plans

We are working towards the development of efficient and ultra-high gain bidirectional converters for various applications on DC microgrids. That should be able of reducing the source ratings and to integrate multiple sources to improve the grid reliability. Design and implementation of bidirectional multi-port converters for various applications of DC microgrids, such as renewable and hybrid storage integration are the scope of our research.

The link to the article- https://ieeexplore.ieee.org/document/10772206