KMITL

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

Browse

Search Results

Now showing 1 - 10 of 10

Some of the metrics are blocked by your
consent settings
The Development of Enteral Feeding for Home-Use Patients
(2025-01-01)
Laokor, Patipan
;
Suksawat, Dusit
;
Wanluk, Nutthanan
;
Thanarak, Jeerawan
;
Chompoo-Inwai, Chai
With the rising number of bedridden patients, affordable and accessible enteral feeding solutions are urgently needed. The high costs of imported feeding systems remain a burden for caregivers, especially in developing regions. This study presents the development of a cost-effective enteral feeding controller that utilizes a unique four-lobe camshaft mechanism, compatible with locally manufactured feeding bags. The redesigned mechanical structure focuses on simplifying the feeding operation while reducing overall device weight. The upgraded electronic control system, combined with a TFT LCD touchscreen, enhances usability. Performance testing demonstrated consistent flow rate accuracy at various levels and showcased the mechanical efficiency of the camshaft-driven feeding system. The successful outcomes of this project have led to commercial interest from a domestic medical device manufacturer, indicating readiness for standardization and mass production.
Some of the metrics are blocked by your
consent settings
Research of Magnetic and Electric Fields to Design and Develop the Prototype of Magnetic Resonance Imaging Device
(2025-01-01)
Chompoo-Inwai, Chai
;
Chompoo-Inwai, Chow
;
Suksathit, Witchayaphorn
;
Kaewpromrat, Weerapat
;
Maneerat, Saranyu
This research presents a study and preliminary design of a main magnetic field generation system for an MRI machine using simulation software. The objective is to investigate the factors affecting magnetic field strength. Six coil models were preliminarily designed and simulated to analyze the magnetic field behavior. Simulation results were compared with experimental magnetic field measurements, showing that the software accurately reproduces the magnetic field. It was found that distributed winding improves field uniformity, and that both the number of coil turns and conductor size directly affect the strength of the main magnetic field in the air core.Based on the simulation outcomes, a prototype magnetic field generation system was designed. The proposed prototype consists of an aluminum core with a diameter of 110 mm and a height of 335 mm, suitable for arm imaging. The system uses a superconducting NbTi wire wound 6,516 turns in eight segments, with a current of 120 A. Cooling is achieved using a cryocooler model RDE-418D4 4K, which can reach temperatures as low as 4.2 K. This study provides essential guidance for the development of main magnetic field systems in future MRI devices.
Some of the metrics are blocked by your
consent settings
Preface
(2024-01-01)
Chompoo-Inwai, Chai
Some of the metrics are blocked by your
consent settings
Severity Heat Mapping for Power System Security Assessment with N-2 Contingency Analysis
(2023-04-01)
Wannoi, Chaisit
;
Wannoi, Narumon
;
Chompoo-Inwai, Chai
This research presents severity heat mapping for a power system security assessment with N-2 contingency analysis. The severity heat map considered the number of devices that exceeded the violation limit for power systems. This study used Thailand's power system in 2019 as the research base, while the Powerworld program was used to simulate and analyze the results. The study considered four cases. The first was the number of devices that exceeded the violation limit, while the second case was the percentage of the maximum branch. The third case was the voltage drops below the controlled value and the last case was the voltage greater than the controlled value. This research focused on studying the stability of the power system in the central region of Thailand, which has the largest difference in load and generation capacity. The results of the N-2 contingency analysis considered the cases of two generators that experienced outages in the system. The results showed that a severity heat map could indicate the devices that could cause an impact or severity on power system stability in each case. Power flow congestion management may then be used to enhance power system stability.
Some of the metrics are blocked by your
consent settings
Novel Techniques for Critical Load Buses Identification and Load Bus's Available Capacity Calculation to Improve Power System Stability
(2020-07-01)
Wannoi, Narumon
;
Jirsuwankul, Nirudh
;
Chompoo-Inwai, Chow
;
Chompoo-Inwai, Chai
;
Wannoi, Chaisit
this paper presents two novel techniques for critical load buses identification and load bus's available capacity (LBAC) calculation to improve power system stability. The critical load bus identification is applied by contingency analysis considering system violation limits under load shedding impact. The violation limits consist of two limits including voltage and percent loading limits of power transfer equipment. As the LBAC calculation, the available transfer capability (ATC) of all multi-lines connected on each load bus are investigated with the total transfer capability (TTC). To validate the effectiveness of the proposed approach, the modified Thailand power system during summer peak load in areal (load center) is used for a system base case. As the results, it is found that the proposed techniques can effectively obtain and rank critical load buses as well as to calculate the LABC. The strong relation between these two indexes can be applied to improve power system stability.
Some of the metrics are blocked by your
consent settings
A novel transmission line's atc assessment method by considering the Generation Dispatch limit (GDL) and renewable generation capacity with power flow sensitivity analysis
(2019-01-01)
Wannoi, Chaisit
;
Wannoi, Narumon
;
Boonkhun, Churirut
;
Temiyasathit, Chivalai
;
Chompoo-Inwai, Chai
This paper presents a novel transmission line's Availability Transfer Capability (ATC) assessment method by considering the Generation Dispatch Limit (GDL) and renewable generation capacity. This method has calculated the power remaining from the Total Transfer Capability (TTC). The TTC in this study is the total generation available declaration of all maximum Generation Shift Factor (GSF) generations to transfer power on transmission line depended on the Power Purchase Agreement of each power generation and of each renewable generation integrated in the system. The maximum GSF generations are defined by using the power sensitivity analysis. Results of this novel method are compared with the traditional transmission line's thermal limit method. Main findings showed that newly proposed method for ATC calculation can be used for the ATC assessment of transmission line and can be a good predictive index to protect power system's voltage stability issue. Moreover, it can be applied to the congestion management scheme with the optimal primary respond generation to control the stability of power transfer on the transmission line.
Some of the metrics are blocked by your
consent settings
Analysis of winding temperature and design of distribution transformer for improving short circuit withstand capability under renewable generations mixed environment
(2018-01-01)
Suechoey, Boonlert
;
Boonseng, Chongrak
;
Chompooinwai, Chow
;
Chompoo-Inwai, Chai
Under renewable generations mixed in today's modern grid system, many of renewable generation resources tend to increase the fault level to an existing power system. Rules and regulation for power equipment and devices need to be revised and updated, of course, no exception for the distribution transformers. This article, therefore, presents the evaluation and analysis of the winding temperature on both loading and short circuit conditions of an oil-immersed distribution transformer and propose the novel transformer design method for improving short circuit withstand capability. In the study, the methodologies of measuring and estimating the winding temperature of the transformer during short circuited are presented and implemented. In the study, various winding parameters are analysed including: the winding temperature, the hottest temperature of the winding after a short circuit, the short circuit current, short circuit force and short circuit duration. The tested and analysed result are benefit for the newly proposed distribution transformer design of a 400 kVA 3 phases 50 Hz 22 kV-400/230 V, Dyn11. The new design approaches will enable designers to find a weak spot and proper selection of raw materials, such as winding size, insulation thickness and properties of the silicon steel for a better quality of distribution transformer. Moreover, the new design can offer lower winding temperature rise of transformer while loading or experiencing with short circuit conditions meaning that it can prolong transformer insulation and extend transformer lifetime.
Some of the metrics are blocked by your
consent settings
Optimal design of a small scale wind power generation system for a rural and low capacity factor area
(2009-12-01)
Chompoo-Inwai, Chai
;
Banjongjit, S.
;
Tangsrianukul, W.
;
Suksawas, D.
;
Lee, Wei Jen
In Thailand, according to the Power Development Plan (PDP 2007), during the year 2007-2021, the government of Thailand plan to have the most economic power generation resources yet reliable and least environmental impact. At the present time, in addition, the emerging energy crisis resulting from an uncertainty price of crude-oil and the emerging global warming crisis results from carbon dioxide emission have drawn an attention about renewable energy all over the world including Thailand [1-2]. One of the most effective solutions for Thailand is to promote the renewable energy usage in the rural area especially from solar energy and wind generation system. However, with the fast growing in wind power technologies, many concerns and focuses pay to this type of renewable energy in the country. Unfortunately, Thailand is considered as a country of low to medium wind speed profile with approximately wind capacity factor close to 30 percent. Therefore, in order to obtain the most efficient and effective wind generation system for rural household usage, the optimal design for a household scale wind generation should be governmentally supported and implemented. This paper, therefore, addresses to this issue and study result shows that the optimal scale of household wind generation system is 5 kW. with a proposed cut-in speed at 2.5 m/s while the suggested rated power at wind speed of 8 m/s. This proposed wind generation system can offer an Optimal Annual Capacity Factor (OACF) close to 30 percent. © 2009 IEEE.
Some of the metrics are blocked by your
consent settings
Design optimization of wind power planning for a country with low-medium-wind-speed profile
(2008-10-13)
Chompoo-Inwai, Chai
;
Chompoo-Inwai, Chow
;
Leelajindakrairerk, Monthon
;
Banjongjit, Sulee
;
Fuangfoo, Pradit
The emerging energy crisis resulting from a high price of crude oil has drawn attention about renewable energy all over the world. Thailand is a developing country located at the heart of Southeast Asia, with about 66 million of population as of 2006. The electricity supply industry structure under the government of Thailand has been managed by the Electricity Generating Authority of Thailand, the Metropolitan Electricity Authority, and the Provincial Electricity Authority for almost 50 years. According to the 2004 Power Development Plan, the country would have generation reserve at a marginal of 15%. Due to the rapid economic growth and difficulty in building new centralized generating facilities, this has the potential to create a security issue of electricity energy shortage and may develop a severe system blackout. Renewable energy issues have been widely discussed and debated over the country. Although solar energy is the most prominent renewable energy source due to the appropriate geographic of Thailand, it is still considered as a low-density energy source which requires a large area of installation. Therefore, for the long-term investment, wind power seems to be a good candidate because it is quick to install, needs no fuel cost, and is environment friendly. Therefore, this paper investigates the impact of the penetration level of wind power generation to be integrated into the Thailand system. System stability has been observed in various system configuration changes due to different control strategies of wind farms. The economic analysis of wind-farm investment has been also considered. © 2008 IEEE.
Some of the metrics are blocked by your
consent settings
Transmission congestion management during transition period of electricity deregulation in Thailand
(2007-11-01)
Chompoo-Inwai, Chai
;
Yingvivatanapong, Chitra
;
Fuangfoo, Pradit
;
Lee, Wei Jen
Transmission congestion management (TCM) plays a significant role in power-system operation under today's deregulated environment. Its two major functions are to maintain power system within security limits and to collect money from market participants paying back to transmission-grid investors. The TCM issue has been widely debated during the past decade. It is still an extensively discussed opened issue in the current competitive environment. In the United States, Pennsylvania New Jersey Merryland (PJM) with nodal congestion management based on renowned locational marginal price and the Electric Reliability Council of Texas with zonal congestion management are two successful stories of TCM under different operation schemes. Although the PJM model is adopted in some developing countries where the processes of restructuring of Electricity Supply Industry is still under the beginning phase, many concerns, such as advances in an information technology, energy security, social equity, price volatility, and the need to subsidize poor consumers, are necessitate factors to be considered before the establishment of TCM and settlement processes. Taking into account the above concerns, this paper proposes a TCM model for the electrical utility industry in Thailand during the transition period to the deregulated environment. © 2007 IEEE.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results