KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 19

Some of the metrics are blocked by your
consent settings
Hamiltonian Control Law with State Observer on Practical Design of Wireless Power Transfer for Autonomous Guided Vehicle Battery Charging Applications
(2026-01-01)
Pairindra, Worapong
;
Somboonpanya, Nattapon
;
Ketjaem, Supakorn
;
Phongsawat, Suwaphit
;
Phophongviwat, Teeraphon
This paper presents the design and calculation of wireless power transfer (WPT) integrated with the Hamiltonian Control Law. The proposed controller demonstrates greater effectiveness in terms of system stability and precise energy control, as compared to the commonly used PI controller in industrial applications. The proposed prototype has been built for assessment in both simulation and implementation, with a rated output power of 500 W and 48 V. The load-independent compensating topology, such as the LCC-S resonant tank, is used to transmit power wirelessly through an air core. Finally, in the last stage, the Hamiltonian Control Law with state observer is applied on the dc-to-dc buck mode converter to control the battery current and overall system. Apparently, the charging current can be precisely regulated to a specific value.
Some of the metrics are blocked by your
consent settings
Quantitative Assessment of EV Energy Consumption: Applying Coast Down Testing to WLTP and EPA Protocols
(2025-07-01)
Phophongviwat, Teeraphon
;
Poopanya, Piyawong
;
Sivalertporn, Kanchana
This study presents a comprehensive methodology for evaluating electric vehicle (EV) energy consumption by integrating coast down testing with standardized chassis dynamometer protocols under WLTP Class 3b and EPA driving cycles. Coast down tests were conducted to determine road load coefficients—critical for replicating real-world resistance profiles on a dynamometer. Energy usage data were measured using On-Board Diagnostics II (OBD-II) and dynamometer measurements to assess power flow from the battery to the wheels. The results reveal that OBD-II consistently recorded higher cumulative energy usage, particularly under urban driving conditions, highlighting limitations in dynamometer responsiveness to transient loads and regenerative events. Notably, the WLTP low-speed cycle exhibited a significantly lower efficiency of 62.42%, with nearly half of the battery energy consumed by non-propulsion systems. In contrast, the EPA cycle demonstrated consistently higher efficiencies of 84.52% (low-speed) and 93.00% (high-speed). Interestingly, high-speed efficiencies between WLTP and EPA were nearly identical, despite differences in total energy consumption. These findings underscore the importance of aligning test protocols with actual driving conditions and demonstrate the effectiveness of combining coast down data with real-time diagnostics for robust EV performance assessments.
Some of the metrics are blocked by your
consent settings
Capacity Forecasting of Lithium-Ion Batteries Using Empirical Models: Toward Efficient SOH Estimation with Limited Cycle Data
(2025-07-01)
Sivalertporn, Kanchana
;
Poopanya, Piyawong
;
Phophongviwat, Teeraphon
Accurate prediction of lithium-ion battery capacity degradation is crucial for reliable state-of-health estimation and long-term performance assessment in battery management systems. This study presents an empirical modeling approach based on experimental data collected from four lithium iron phosphate (LFP) battery packs cycled over 75 to 100 charge–discharge cycles. Several mathematical models—including linear, quadratic, single-exponential, and double-exponential functions—were evaluated for their predictive accuracy. Among these, the linear and single-exponential models demonstrated strong performance in early-cycle predictions. It was found that using 30 to 40 cycles of data is sufficient for reliable forecasting within a 100-cycle range, reducing the mean absolute error by over 80% compared to using early-cycle data alone. Although these models provide reasonable short-term predictions, they fail to capture the nonlinear degradation behavior observed beyond 80 cycles. To address this, a modified linear model was proposed by introducing an exponentially decaying slope. The modified linear model offers improved long-term prediction accuracy and robustness, particularly when data availability is limited. Capacity forecasts based on only 40 cycles yielded results comparable to those using 100 cycles, demonstrating the model’s efficiency. End-of-life estimates based on the modified linear model align more closely with typical LFP specifications, whereas conventional models tend to underestimate the cycle life. The proposed model offers a practical balance between computational simplicity and predictive accuracy, making it well suited for battery health diagnostics.
Some of the metrics are blocked by your
consent settings
The Development of a 1 kW Mid-Range Wireless Power Transfer Platform for Autonomous Guided Vehicle Applications Using an LCC-S Resonant Compensator
(2025-06-01)
Pairindra, Worapong
;
Phongsawat, Suwaphit
;
Phophongviwat, Teeraphon
;
Khomfoi, Surin
This study presents the development, simulation, and hardware implementation of a 48 V, 1 kW mid-range wireless power transfer (WPT) platform for autonomous guided vehicle (AGV) charging in industrial applications. The system uses an LCC-S compensation topology, selected for its ability to maintain a constant output voltage and deliver high efficiency even under load variations at a typical coil distance of 15 cm. It can also operate at different distances by adjusting the compensator circuit. A proportional–integral (PI) controller is implemented for current regulation, offering a practical, low-cost solution well suited to industrial embedded systems. Compared to advanced control strategies, the PI controller provides sufficient accuracy with minimal computational demand, enabling reliable operation in real-world environments. Current adjustment can be dynamically carried out in response to real-time changes and continuously monitored based on the AGV battery’s state of charge (SOC). Simulation and experimental results validate the system’s performance, achieving over 80% efficiency and demonstrating its feasibility for scalable, robust AGV charging in Industry 4.0 Manufacturing Settings.
Some of the metrics are blocked by your
consent settings
Enhancing Grid Stability Using a Virtual Inertia-Integrated Railway Power Conditioner in Railway Power Supplies With High Renewable Energy Penetration
(2024-01-01)
Phophongviwat, Teeraphon
;
Boonlert, Thunwa
;
Hongesombut, Komsan
As electric power systems increasingly integrate Renewable Energy Sources (RESs), the consequent reduction in system inertia has heightened their sensitivity to disturbances, such as sudden load changes. This issue is especially relevant in railway power supply systems, which are evolving to be dominated by RESs. Traditional solutions, including Railway Power Conditioners (RPCs), primarily address unbalanced loads and reactive power compensation but offer limited frequency support. This paper introduces a Virtual Inertia-Integrated Railway Power Conditioner (VIIRPC), a novel solution that enhances traditional RPCs with Energy Storage Systems (ESS) to provide critical virtual inertia support, thereby addressing the critical gap in frequency stability amidst the evolving energy landscape of railway systems. Utilizing a current source-based model, the VIIRPC effectively extends inertia support from two-phase systems to balanced three-phase systems at the Point of Common Coupling (PCC). This achievement is realized by dividing a virtual inertia signal and integrating it into both sides of the RPC control loop, while respecting each side's signal orientation. Simulations have been conducted to verify the operation under different loading conditions, including a 4-minute headway train schedule, under both conventional and low-inertia grid conditions. These results demonstrate that the VIIRPC outperforms traditional RPCs by enhancing frequency stability and maintaining conventional functionalities. This advancement is particularly significant for modern, RES-dominated railway power supplies, especially in remote areas with RES-based power sources and low short-circuit levels at the PCC.
Some of the metrics are blocked by your
consent settings
EV Charging Station Planning Based on Nearby Station Data
(2024-01-01)
Somboonpanya, Nattapon
;
Ketjaem, Supakorn
;
Khomfoi, Surin
;
Phophongviwat, Teeraphon
;
Thounthong, Phatiphat
This paper presents the optimal electric vehicle charging station installation planning, focusing on the installation scenarios where the location is pre-selected. The optimization process includes the maximum charging power capacity and the number of electric vehicles charging stations. Energy consumption information from nearby charging stations is harvested and then analyzed for forecasting the energy supply behavior of each charging station. This paper has a financial analysis to evaluate the cost-effectiveness of each installation scenario. Additionally, this methodology is demonstrated through the real-world data of charging patterns from electric vehicles at each charging station in Thailand.
Some of the metrics are blocked by your
consent settings
A Review of Converters for Green Hydrogen Generation in Consideration of Renewable Energy
(2024-01-01)
Vivanthanarot, Saman
;
Khomfoi, Surin
;
Phophongviwat, Teeraphon
;
Somboonpanya, Nattapon
;
Phongsawat, Suwaphit
Hydrogen is set to revolutionize the future energy landscape with its wide-ranging applications across various sectors. With global decarbonization objectives, water electrolysis provides a sustainable way to produce hydrogen, especially when it is driven by renewable energy sources. This process predominantly utilizes grid electricity, but the growing implementation of renewable energy-powered microgrids presents an attractive alternative for hydrogen production. The produced hydrogen can be used not only for electrical generation within the microgrid but also for local heating and as a fuel for transportation. Power converters are crucial in ensuring stability and reliability in hydrogen production. The paper reviews the power electronics converters required to match the DC and AC voltage source with the needs of electrolyzers. Moreover, this paper explores the technologies of electrolyzers powered by renewable energy sources, with a particular focus on wind turbines and PV.
Some of the metrics are blocked by your
consent settings
CC-CV Charging Control Based on Modified Hamiltonian Control Law for EV Application
(2024-01-01)
Somboonpanya, Nattapon
;
Khomfoi, Surin
;
Phophongviwat, Teeraphon
;
Jamshidpour, Ehsan
;
Thounthong, Phatiphat
This paper proposes constant current-constant voltage (CC-CV) charging control based on Hamiltonian control law with a state observer for a bidirectional buck-boost converter on an EV charger. The CC-CV charging scheme is mainly utilized to charge lithium-ion batteries on an electric vehicle. In CC mode, the battery is charged with a preset value until the battery voltage reaches the desired equalized voltage. During CV mode, equalized current is used to maintain battery voltage to equalize the battery. In this work, equalization current requires the actual battery voltage, desired battery voltage, and the battery current for its calculation. Additionally, a state observer is implemented to estimate voltage across uncertainties of resistance and the battery current. Also, it can enhance the performance of the proposed control scheme and minimize the required sensors. Furthermore, the 1 kW prototype of the bidirectional buck-boost converter is developed to demonstrate the feasibility of the proposed controlled scheme.
Some of the metrics are blocked by your
consent settings
Control Strategy of Interleaved Buck Converter for Automated Guided Vehicles with Misalignment in Wireless Power Transfer Systems
(2024-01-01)
Phongsawat, Suwaphit
;
Pairindra, Worapong
;
Khomfoi, Surin
;
Phophongviwat, Teeraphon
;
Takorabet, Noureddine
The analysis of the positioning of the power transmission coil with a power rating of 3 kW and an output voltage of 48 V at a frequency of 85 kHz is presented, along with a simulation of the wireless power transfer (WPT) control system using an LCC-S resonance compensation circuit, applied to automated guided vehicles (AGVs). The case where the coil positions are misaligned with a deviation of 0-20% from the size of the power transmission coil is considered. Apparently, it can be illustrated that when the two power transmission coils are misaligned, the battery can still be charged in constant current mode using an interleaved buck converter circuit through a PI controller to increase the output power. The operation is simulated using MATLAB/Simulink software.
Some of the metrics are blocked by your
consent settings
Technical Assessment of Reusing Retired Electric Vehicle Lithium-Ion Batteries in Thailand
(2023-06-01)
Phophongviwat, Teeraphon
;
Polmai, Sompob
;
Maneeinn, Chaitouch
;
Hongesombut, Komsan
;
Sivalertporn, Kanchana
A rapid growth in electric vehicles has led to a massive number of retired batteries in the transportation sector after 8–10 years of use. However, retired batteries retain over 60% of their original capacity and can be employed in less demanding electric vehicles or stationary energy storage systems. As a result, the management of end-of-life electric vehicles has received increased attention globally over the last decade due to their environmental and economic benefits. This work presents knowledge and technology for retired electric vehicle batteries that are applicable to the Thai context, with a particular focus on a case study of a retired lithium-ion battery from the Nissan X-Trail Hybrid car. The disassembled battery modules are designed for remanufacturing in small electric vehicles and repurposing in energy storage systems. The retired batteries were tested in a laboratory under high C-rate conditions (10C, 20C, and 30C) to examine the limitations of the batteries’ ability to deliver high current to electric vehicles during the driving operation. In addition, the electric motorcycle conversion has also been studied by converting the gasoline engine to an electric battery system. Finally, the prototypes were tested both in the laboratory and in real-world use. The findings of this study will serve as a guideline for the sorting and assessment of retired lithium-ion batteries from electric vehicles, as well as demonstrate the technical feasibility of reusing retired batteries in Thailand.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results