Faculty Publications

Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736

Publications by NITK Faculty

Browse

Search Results

Now showing 1 - 4 of 4
  • Item
    Development of Small Signal Model and Stability Analysis of PV-Grid Integration System for EV Charging Application
    (Institute of Electrical and Electronics Engineers Inc., 2024) Kanimozhi, K.; Koothu Kesavan, K.K.; Nagendrappa, N.; Balasubramanian, B.
    In this article, grid interactive photovoltaic (PV) system is designed for an electric vehicle (EV) charging application, and the stability of the system is analyzed. The small signal model for the system is derived by averaging and linearizing the state space equations, and the condition for stable operation of PV-integrated charger system is identified from the transfer functions. The proposed charger system implements a coordinated control between the converters to maintain a power balance between the sources and load. System stability is examined using root-locus plots and in addition, the controller is designed to improve the overall stability and reliability of the system. The proposed method provides a general framework for modeling EV charging systems which also details the importance of deriving the model with multiple energy sources. Further, proposed topology has bidirectional capability, which transfers excess PV power to the grid during off-charging hours. The efficacy of the proposed method is verified using the MATLAB Simulink environment for the different scenarios, i.e., variation in the irradiation and disturbances in the grid voltage. The experimental study is conducted on a 1.5-kW laboratory prototype using a low-cost digital signal processing controller (launchpad TMS320F28027F) and the measured results authenticate the simulation findings. © 2020 IEEE.
  • Item
    Efficient and cost-effective wireless CC/CV charging for electric vehicles: A bipolar duty cycle approach
    (Elsevier Ltd, 2024) Vinod, M.; Kishan, D.; Dastagiri Reddy, B.D.; Nagendrappa, N.
    Inductive Power Transfer (IPT) has gained significant popularity in recent times, particularly in electric vehicle (EV) battery charging applications. To achieve optimal battery charging, it is imperative to implement both constant current (CC) and constant voltage (CV) modes of operation. Traditionally, CC/CV modes are attained through conventional phase shift techniques, frequency modulation schemes, the use of active converters, and additional compensator circuits and coils. However, these conventional methods not only reduce system efficiency but also escalate overall costs and control complexity on the onboard side. This article proposes a novel bipolar duty cycle control strategy for a series–series resonant IPT system, aiming to achieve CC/CV modes of operation. The proposed control strategy increases the number of switches operated with zero voltage switching, compared to other fixed-frequency phase shift control strategies across a wide load range. Furthermore, the article provides a detailed procedure for implementing the voltage and current compensator. Additionally, it describes the construction of a one-kilowatt laboratory prototype using Sic devices, presenting the obtained results. The peak measured DC–DC efficiency of 93.8 % is achieved at a distance of 150 mm, and the efficiency has also been evaluated under misalignment conditions. © 2024 Elsevier Ltd
  • Item
    Design and Laboratory Validation of a Grid-Interfaced Totem-Pole PFC Converter With PR Controller and Isolated Phase Modulated Converter for Solar-Powered Next-Gen EV Charging System
    (China Power Supply Society, 2025) Kanimozhi, K.; Kesavan, P.K.; Nagendrappa, N.; Balasubramanian, B.
    This paper proposes a stationery reference frame proportional-resonant (PR) controller for current control of grid-tied converters in an EV charger application. Since it is a viable alternative to rotational reference frame PI compensators in AC applications, the PR controller has been adopted for achieving zero steady state error without using any computationally intensive reference frame transformations. In this paper, a method to design the structure of PR controller and its coefficients according to the desired transient behaviour of AC signal amplitude in PFC converter current loop has been proposed. The importance of suggested PR controller design method is that the grid current magnitude is varying constantly based on the available PV power and battery charger levels which necessitates the controller to act in desired transient behaviour. So, by this way the impact of variation in system parameters have been completely overcome by operating the converter controllers appropriately in a solar powered EV charger system. To verify the effectiveness of the proposed controller design, extensive simulations and experimental studies are performed in a 1.5 kW EV charger system under various PV irradiances and charger power levels. The experimental results obtained from the laboratory prototype confirms the simulation findings. © 2025 China Power Supply Society. All rights reserved.
  • Item
    Implementation of Coordinated Control and Power Flow Management Strategy for a Solar Powered EV Charging System
    (Institute of Electrical and Electronics Engineers Inc., 2025) Kanimozhi, K.; Koothu Kesavan, P.; Nagendrappa, N.; Balasubramanian, B.
    This paper introduces a novel coordinated control and power flow management strategy (CC-PFMS) for a solar integrated electric vehicle (EV) charging system. The CC-PFMS is designed to have inherent power balance capability under various operating modes with multiple energy resources. Further, it will facilitate the direction of power flow from grid to battery or vice versa irrespective of the charger system dynamics. The main advantage of proposed strategy is to identify different conditions such as change in solar irradiance, vehicle availability and battery charging/discharging state and ensure the stable operation. The veracity of the new approach is tested on 1.5 kW charger system having photovoltaic (PV) source integrated with utility grid. The performance of CC-PFMS under various operating modes viz. grid to vehicle (G2V), vehicle to grid (V2G), PV to vehicle (PV2V), PV to grid (PV2G), G2V+PV2V, V2G+PV2G and PV2V+PV2G is substantiated through extensive MATLAB simulations. The experiments were also performed in the laboratory prototype to confirm the simulation findings and recorded results were presented. © 1975-2011 IEEE.