KMITL

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

Browse

Search Results

Now showing 1 - 8 of 8

Some of the metrics are blocked by your
consent settings
Water ozonisation/ozonation for ASEAN environmental resource sustainability: A structural equation model analysis
(2018-01-01)
Potivejkul, Siriwat
;
Pimde, Paitoon
Some of the metrics are blocked by your
consent settings
Analysis of frequency converters for PD test
(2017-10-27)
Kitcharoen, Phattarin
;
Kunakorn, Anantawat
;
Yutthagowith, Peerawut
;
Potivejkul, Siriwat
This paper presents the analysis of an AC-AC converter used in partial discharge test. In this paper, the analysis of the frequency converter is separated into two parts. Firstly, the converter models are simulated by a circuit simulation program for comparing noise signals generated by the 2-level SFC and 5-level SFC. The frequency of the converter was set to be 200 Hz. With the help of the simulator, the approach for noise mitigation with filter application is designed and applied to the PD test system. In the second part, the developed static frequency converters are used in the partial discharge tests for confirming the simulation results. From all simulated and experimental results, it can be concluded that the 5-level SFC has high efficiency, low generated noise signal, and also very attractive for using in partial discharge test.
Some of the metrics are blocked by your
consent settings
Grounding system design of substation using matlab program
(2017-10-19)
Kapijan, Prateep
;
Potivejkul, Siriwat
;
Yutthagowith, Peerawut
Substation grounding system of Provincial Electricity Authority (PEA) are normally designed using CDEGS software. However, the copyright and limited user licenses affect the practical use. Therefore, using an alternative software should be more beneficial and cost-effective. MATLAB, an engineering software, has been utilized in this study to design the substation grounding system of non-uniform soil. The formulas used in this program are cited from previous literatures and followed the IEEE80-2000. The parameters, including grid resistance (Rg), grid potential rise (GPR), mesh voltage (Em), and step voltage (Es), are in accordance with the results from CDEGS software.
Some of the metrics are blocked by your
consent settings
Perceptions on ozonation water treatment use: An alternative idea for ASEAN water resource sustainability
(2017-06-01)
Potivejkul, Siriwat
;
Pimdee, Paitoon
;
Phimolsathien, Thepparat
Ozonation (or ozonisation) is a chemical water treatment technique based on the infusion of ozone into water. As early as 1893, this process was used in Europe for the treatment of drinking water and as recently as 2014, the most modern ozone water treatment facility in the world was brought online to protect the waters of Switzerland's Lake Geneva. However, studies vary widely in conditions leading to ozone technology use, and the subsequent factors concerning its effectiveness. From a population of 7,006 Thai industrial estate companies, a sample of 500 executives, managers, and engineers was drawn which completed an 80-item survey which was analysed by use of a structural equation model using LISREL 8.72. Results showed that acceptance had the greatest influence on ozonation treatment technology use, while the remaining five latent variables (ranked in importance) included curiosity, provisional trial, testing, cognizance, and strategy.
Some of the metrics are blocked by your
consent settings
Comparison of voltage-time to surface failure of various insulation material for space aerial cables
(2017-02-01)
Krirapee, Sathit
;
Potivejkul, Siriwat
;
Pattanadech, Norasage
This paper aims to represents the investigation of surface tracking resistance of various types of cable insulations. Five kinds of cable material i.e. non carbon filled crosslink polyethylene (XLPE), carbon filled XLPE, low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE) were examined. The test specimen has a dimension of 10 mm in width, 50.8 mm in length and 1.52 mm in thickness. The test samples were classified into two groups for investigation. The former group was the new test samples, whereas the latter test samples were stressed by thermal ageing with 120°C for 168 hours. Then both specimens were examined. One side of the specimen was contacted with high voltage electrode terminal made of 1 mm diameter Nichrome wire. Another side of the test specimen was dipped into 0.1 percent solution of ammonium chloride as grounded electrode. The spacing between electrodes at dry area was determined for 25.4 mm. After completion of the test set up, AC high voltage was applied to the test specimen. The dip rate of the specimen into the solution was set up as 4 times per minute. The test voltage level was in the range of 1-3.5 kV. The experiment was performed in accordance with ICEA S-66-524 (Method B). The test voltage was applied to the test specimen until the insulation failure could be observed. Then, the insulation failure voltage and failure time were recorded. The test results illustrated that both unaged and aged HDPE and non carbon filled XLPE provided the higher surface tracking resistance than carbon filled XLPE, LDPE and MDPE respectively. Besides, the thermal stress aging had not much effect on the surface tracking resistance characteristic of tested material. It can be summarized that the material structure much more influenced the surface tracking characteristic of the cable material.
Some of the metrics are blocked by your
consent settings
Comparison of Voltage-time to Surface Failure of Various Insulation Material for Space Aerial Cables
(2016-01-01)
Krirapee, Sathit
;
Potivejkul, Siriwat
;
Pattanadech, Norasage
This paper aims to represents the investigation of surface tracking resistance of various types of cable insulations. Five kinds of cable material i.e. non carbon filled crosslink polyethylene (XLPE), carbon filled XLPE, low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE) were examined. The test specimen has a dimension of 10 mm in width, 50.8 mm in length and 1.52 mm in thickness. The test samples were classified into two groups for investigation. The former group was the new test samples, whereas the latter test samples were stressed by thermal ageing with 120<sup>o</sup>C for 168 hours. Then both specimens were examined. One side of the specimen was contacted with high voltage electrode terminal made of 1 mm diameter Nichrome wire. Another side of the test specimen was dipped into 0.1 percent solution of ammonium chloride as grounded electrode. The spacing between electrodes at dry area was determined for 25.4 mm. After completion of the test set up, AC high voltage was applied to the test specimen. The dip rate of the specimen into the solution was set up as 4 times per minute. The test voltage level was in the range of 1-3.5 kV. The experiment was performed in accordance with ICEA S-66-524 (Method B). The test voltage was applied to the test specimen until the insulation failure could be observed. Then, the insulation failure voltage and failure time were recorded. The test results illustrated that both unaged and aged HDPE and non carbon filled XLPE provided the higher surface tracking resistance than carbon filled XLPE, LDPE and MDPE respectively. Besides, the thermal stress aging had not much effect on the surface tracking resistance characteristic of tested material. It can be summarized that the material structure much more influenced the surface tracking characteristic of the cable material.
Some of the metrics are blocked by your
consent settings
Structural equation model of the adoption of ozone generator technology by thai industries
(2015-01-01)
Potivejkul, Siriwat
;
Phimolsathien, Thepparat
;
Pimdee, Paitoon
Ozone is second only to fluorine as the most powerful oxidant in the world. It's the most powerful, natural air and water sanitizer readily available and can break down chemicals into their basic naturally-occurring component parts. The objectives of this study were therefore, to test a model of technology adoption used in the ozone generator industry in Thailand. Self-reporting questionnaires were retrieved from 500 production and engineering managers in both central and eastern Thailand enterprises from a total of 3,000 distributed. The research framework integrates Corporate Vision, Awareness, Interest, Evaluation and Trial to hypothesize a theoretical model to explain and predict adoption of ozone generator technology. All latent variables in the model have a positive influence on the adoption of Thai ozone generator technology. The model furthermore consisted of 18 observed variables with a variable latency of 6 variables which had a positive influence on the adoption of ozone generator technology. The final structural model was verified to achieve a good fit with the empirical data at 65% because of the decision to use new products in ozone generator technology. Using LISREL 8.72 Structural Equation Modeling (SEM), the results showed that that the variables that influence technology use the most are Adoption, followed by Interest and Evaluation, followed by Trial, Awareness and Corporate Vision having the effects of 0.73, 0.53, 0.42, 0.31 and 0.23, respectively.
Some of the metrics are blocked by your
consent settings
Design and construction of a prototype saline solution resistive voltage divider
(2013-09-02)
Phoaphan, Busayapol
;
Potivejkul, Siriwat
;
Chaisiri, Punyavee
;
Yutthagowith, Peerawut
This paper presents design and construction of a prototype resistive voltage measuring system composing of a saline solution divider and resistive attenuator. The structure of the developed divider is designed in form of coaxial cylinder. The system has voltage rating of 300 kV. The developed measuring system has been test according to the IEC standard composing of unit step response test, scale factor test, withstand voltage test, and short term stability test. The experimental response times of the developed voltage measuring systems without and with shielding ring are about 50 ns and 25 ns, respectively. This accomplishment will be advantage for increasing capability of HV laboratory and for researches, which are about effect of fast transient voltage in transmission and distribution systems in Thailand. © 2013 IEEE.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results