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The six electric fault zone analysis for predictive maintenance on motors of the continuous production
(2022-01-01)
Arttama, Kritsakorn
;
Jettanasen, Chaiyan
This paper proposes for motor health analysis by classifying into six fault zones. These consist of power quality, power circuit, insulation, stator, rotor, and air gap. First of all, power quality would consider on the quantity between voltage and current. Secondly, power current plays a role on the current supplied to the motor. Thirdly, insulation would take a focus on insulation's health among windings and ground. Fourth, stator condition concerns insulation of windings, solder joints between the coils and the stator core. Fifth, rotor focuses on the condition of both rotor cage and lamination. Lastly, air gap would mainly concern concentricity between rotor and stator. All of these fault zones would be diagnosed for condition-based monitoring with the aims to prevent any premature damage on motor and also to saves maintenance costs.
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HPFs filtering solutions for reduced the harmonic current generated by SMPS and ac drive systems
(2020-02-01)
Kularbphettong, K.
;
Boonseng, C.
This paper proposes a reduced 2nd, 3rd, 5th and 7th harmonic current of all power supply units and ac drives which effects of heating neutral cables and transformer. The commercial or automation building require the operation of many parallel-connected switch mode power supply and ac drive on the same bus and transformer. Such a system significantly increases the high neutral current and power quality problems on the distribution network. The existing system mainly consists of switch mode power supply and a three phase ac drive for compressor loads (common to HVAC applications). A passive power filter (PPF) and a low rating APF (Active Power Filter) at point of common coupling (PCC) are used to power quality enhancement in the distribution system. A PPF is designed to reduce the harmonics and to compensate the reactive power in the distribution system and the APF located at an upstream position near main distribution broads (MDB), it performs the compensation for harmonic current which is produced from all of drive and for remaining harmonics after the PPFs can been operation. The Hybrid Power Filter System (HPFs) is the combination of PPF and APF which mostly use for reducing harmonic currents and improving power quality of the system. Finally, using the HPFs to solve this problem, the results can reduce distortion and neutral current.
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The Harmonic and Power Quality Improvement of Office Building Using Hybrid Power Filter
(2019-10-01)
Boonseng, C.
;
Kularbphettong, K.
This paper proposes a reduced 2nd, 3rd, 5th and 7th harmonic current of all power supply units and ac drives which effects of heating neutral cables and transformer. The commercial or automation building require the operation of many parallel-connected switch mode power supply and ac drive on the same bus and transformer. Such a system significantly increases the high neutral current and power quality problems on the distribution network. The existing system mainly consists of switch mode power supply and a three-phase ac drive for compressor loads (common to HVAC applications). A passive power filter (PPF) and a low rating APF (Active Power Filter) at point of common coupling (PCC) are used to power quality enhancement in the distribution system. A PPF is designed to reduce the harmonics and to compensate the reactive power in the distribution system and the APF located at an upstream position near main distribution broads (MDB), it performs the compensation for harmonic current which is produced from all of drive and for remaining harmonics after the PPFs can been operation. The Hybrid Power Filter System (HPFs) is the combination of PPF and APF which mostly use for reducing harmonic currents and improving power quality of the system. Finally, using the HPFs to solve this problem, the results can reduce distortion in current.
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Harmonics and reduction of energy consumption in lighting systems by using led lamps
(2018-11-01)
Phannil, Natthanon
;
Jettanasen, Chaiyan
;
Ngaopitakkul, Atthapol
This paper proposes the study and analysis of harmonics, energy consumption and power quality of light emitting diode (LED) lamps equipped in building lighting systems. LED lamps with external (LED MR16) and internal (LED light bulb) drivers are investigated using an experimental setup to compare the results. The power quality of both LED lamps is studied by using a power quality meter to measure the generated harmonic currents from various case studies. The case study is divided into four major cases: one LED lamp is turned on with one driver, two LED lamps are turned on using the two drivers, eight LED lamps are turned on with one driver, and eight LED lamps are turned on with the eight drivers. As harmonics are related to total power factor (PF), which affects the energy savings of the building, hence, a filtering circuit to reduce harmonic current has been designed and implemented to improve power quality and/or power factor of the system. The different cases of harmonic filter insertion at the input of an LED lamp's driver are discussed and then compared with a lighting standard to show the effectiveness of the passive filtering technique used in the studied system. In addition, the obtained result can be applied to both newly built and retrofitted buildings that aim to use LED technology to increase energy efficiency and decrease energy costs, and could be a helpful guide for end-users and manufacturers in addressing and developing LED issues.
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Development of a partial discharge testing system for potential transformers
(2018-04-27)
Prombud, T.
;
Kitcharoen, P.
;
Yutthagowith, P.
In this paper, the development of a partial discharge testing system for potential transformers (PTs) is presented. The system is composed of a low-voltage and 200-Hz power frequency converter connected with a low pass filter, a high-voltage transformer, and a conventional partial discharge detection system. The performances of the converter with three generated waveform, i.e. square wave, quasi-square wave, and unipolar pulse width modulation (PWM) are compared in terms of the DC charging voltage, the voltage difference (peak voltage/square root of 2 and rms voltage), total harmonic distortion of the output high voltage (THDv), and background noises in the partial discharge test. It is found that the unipolar PWM frequency converter provides the best performances in terms of the voltage difference, THDv, and background noise. The voltage difference and THDv are lower than 5%, and the background noise is less than 2.5 pC. In addition, the developed system has been used for the real partial test on a potential transformer in the distribution system successfully.
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Comparative study of lighting quality and power quality for LED and HPS luminaires in a roadway lighting system
(2018-01-15)
Yoomak, Suntiti
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Jettanasen, Chaiyan
;
Ngaopitakkul, Atthapol
;
Bunjongjit, Sulee
;
Leelajindakrairerk, Monthol
Roadway lighting was one of the earliest applications for electric lighting technologies. Well-designed roadway lighting offers many benefits and aids the visual tasks of drivers and pedestrians. Currently, the trend of energy management for exterior general lighting has increased in several cities. Generally, high-pressure sodium (HPS) lamps have been the standard throughout Thailand since the 1980s, but the use of HPS lamps has driven high energy consumption. To conserve energy, light emitting diode (LED) street lighting has quickly become a new trend. The primary objective of this paper is to deliver an initial and in-depth assessment of LED technology for roadway lighting applications. This analysis focuses on the performance of LED luminaires compared with the existing standard of HPS cobra-head luminaires in terms of lighting quality, energy savings, power quality, and investment. The analysis is conducted via three components. First, simulation of the roadway lighting quality is performed using the DIALux programme to evaluate and compare with the standard of Thailand. Second, an experimental setup is used to evaluate the energy savings and power quality for cases with and without solar power. Third, the discounted payback period (DPP) criterion and internal rate of return (IRR) are applied to evaluate the investment scenarios. The obtained results conclude that the LED luminaire performs better than the HPS luminaire in terms of power quality and energy savings (energy-efficient index reduction of approximately 40% over the HPS luminaire), which indicates that the utility benefits from use of LED luminaires. However, although the lighting quality results for LED luminaire have values fairly close to that of the standard, the lighting quality should be improved in terms of uniformity. The results obtained from this analysis are expected to help to improve the roadway lighting standard of Thailand in the future.
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Power quality analysis of grid connected solar power inverter
(2017-07-25)
Phannil, Natthanon
;
Jettanasen, Chaiyan
;
Ngaopitakkul, Atthapol
Photovoltaic (PV) energy has been widely interested today because it is clean and endless energy without causing pollution. To produce electricity from solar energy, it would be required an inverter to convert the direct current into alternating current. The inverter is the cause of problems that affect the stability of the power system because it is a switching device served to adjust the frequency of the AC power as needed. At the same time, it can cause harmonics which result in waveform distortion and affect electronic devices that receive power. Then, it could make electronic device malfunction. This paper studies the characteristics of harmonics on grid, PV system, and load. The result shows that most grid's harmonics are affected from PV system and load when the inverter power up to almost the rated power, meanwhile, percentages of harmonics are reduced and harmonics of load depend on the type of load. Next, comparing harmonics on three sides, and found that harmonics of PV system hardly affect to load and harmonics of grid are more affected from load than PV system.
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Analysis of harmonics in indoor Lighting System with LED and fluorescent luminaire
(2017-07-25)
Bunjongjit, S.
;
Ngaopitakkul, A.
;
Leelajindakrairerk, M.
Lighting system is an important part in everyday life. Today, lighting technology has been developing in many aspects. Technology such as Light Emitting Diode (LED) luminaire has been applied to indoor lighting system to replace conventional luminaire. LED lamps have many advantages such as less energy consumption, long life cycle and environmental friendly issue due to without toxic component. However, installation cost is main concern for investor regarding changing conventional lamp toward LED. So, the lighting system in some building are consist of both conventional and LED luminaires. In such a case the power quality must be taken into consideration. This paper aims to study power quality problem in term of harmonics generated by lighting system consisting of both fluorescent and LED luminaires. The obtained result can be used to design filter circuit for harmonic reduction in lighting system.
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The study of harmonic reduction in Light Emitting Diode (LED) roadway lighting system
(2016-07-25)
Yoomak, Suntiti
;
Ngaopitakkul, Atthapol
Since electrical energy is essential in human life, it is necessary to find out a way to reduce its consumption. In the past, in Thailand, they had to provide much energy to roadway lighting system because main lighting equipment has consumed high energy to generate lighting in the roadway. But today, we are increasingly aware of energy consumption. As a result, Light Emitting Diode (LED) luminaires are considered to be used in roadway lighting system, to replace conventional inefficient lighting lamps; this is due to their greater energy efficiency, high color rendering index (CRI) (70-90), and long life. However, LED luminaires have some disadvantages concerning harmonic generation issued from LED's driver. Hence, in this paper, LED luminaire will be studied in terms of power quality improvement by using AC-side Inductor Harmonic Filter. An experimental setup will be designed to measure the electrical parameters. The experimental results show that, without the filter, LED luminaire contains much harmonic current distortion (THDi), but when inserting the filter, the harmonic current distortion is decreased. However, to ensure the overall functioning of the system, the final results of harmonic current distortion should be complied with the limit value of IEC 61000-3-2 standard.
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Power quality analysis in light emitting diode lamps
(2016-07-25)
Ananwattanaporn, Santipont
;
Ngaopitakkul, Atthapol
Lighting system plays an important role in every life to increase quality of life and working efficiency. As population increase, urban area has been grown rapidly resulted in increased energy consumption in every section including lighting system. With the current attention in energy and environment issue, many governments have set policy to increase energy efficiency. In lighting system, conventional luminaire with low energy efficiency has been replaced with newer technology with low energy consumption and high energy efficiency such as light emitting diode (LED). Today, LED luminaire has taken considerable proportion of market share; however, the main concern regarding changing conventional lamp toward LED is power quality. This paper aims to study power quality issue in term of generated harmonics from lighting system consisting of LED lamps. The result indicates that LED lamps generate significant amount of current harmonic and cause a distortion in waveform. Thus, it needs taking power quality issue into account before replacing or installing LED into lighting system.

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