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Performance and electromagnetic interference mitigation of DC-DC converter connected to photovoltaic panel
(2019-11-01)
Jettanasen, C.
;
Pothisarn, C.
Renewable energy has been rapidly increased in terms of installed capacity. However, the electronic components inside such a system can cause a serious threat such as Electromagnetic Interference (EMI) to nearby sensitive devices/equipment. This paper aims to study on performance of DC-DC boost converter connected to photovoltaic panel and how to reduce EMI emissions issued in the system. A passive EMI low-pass filtering is one of various mitigation techniques. The designed converter connected to photovoltaic panel and EMI filter are tested in both simulation software and field testing by using EN55022 standard as a reference.
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The effects of multi-distributed generator on distribution system reliability
(2018-06-08)
Ngaopitakkul, A.
;
Jettanasen, C.
The paper investigates on the effects of multi- distributed generators (multi-DG) integrated to distribution system in terms of reliability indices. The distributed generators (DGs) under this study are solar photovoltaic (PV) connected to a 22 kV distribution system. In addition, it presents to determine the system average interruption frequency index (SAIFI), the system average interruption duration index (SAIDI) and outage cost as reliability indices by comparing the SAIFI, SAIDI and outage cost (ECOST) of the cases that multi-DG is connected to a distribution system. The reliability indices will be calculated using data obtaining from simulation and analysis of power distribution system model created in DIgSILENT PowerFactory. The overall results can be summarized by focusing on the capacity of DGs and the location of DGs, which are important factors capable of affecting the reliability indices.
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Performance and electromagnetic compatibility of a photovoltaic power converter
(2017-07-02)
Jettanasen, C.
;
Pothisarn, C.
This study aims to evaluate the performance of DC-DC converter in photovoltaic system. Electromagnetic compatibility (EMC) characteristics, issues and its effect on photovoltaic power converter are performed and taken into consideration. ĆUK converter has been built in this research. The proposed filter circuit is also created and integrated in ĆUK converter in photovoltaic system, and tested in field testing. The EN 55011 standard has been applied as a reference in order to verify the performance of the proposed filter circuit in terms of Electromagnetic Interference (EMI) reduction in actual application.
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Energy savings analysis and harmonics reduction for the electronic ballast of T5 fluorescent lamp in a building's lighting system
(2015-06-15)
Chiradeja, P.
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Ngaopitakkul, A.
;
Jettanasen, C.
Lighting is one of the major energy end uses, which accounts for approximately 20-30% of electricity consumption in buildings. In fact, the fluorescent lamp is the most employed lamp in a lighting system for both inside and outside the building. The ballast is one of the major components of fluorescent lamps; it exists commercially as an electromagnetic ballast, a low loss ballast and an electronic ballast. To reduce energy consumption in a lighting system, the electronic ballast has already been introduced for profit in terms of its peak demand reduction and energy conservation in the building. However, when the electronic ballast functions, harmonics will be generated. Hence, this paper investigates energy savings and the generation of harmonics when using a fluorescent T5 lamp with electronic ballast in a building. The efficiency indices in terms of illumination, energy savings, and harmonics are also evaluated and compared with the fluorescent T8 lamp operating with a low watt loss electromagnetic ballast, which is also widely used. The obtained results are useful for the design and decision to install a fluorescent T5 lamp with electronic ballast in building lighting system to conserve energy and/or reduce energy consumption for the future of the country.
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Performance analysis of maximum power transfer in piezoelectric energy harvesting
(2015-01-01)
Songsukthawan, P.
;
Jettanasen, C.
Using piezoelectric materials to harvest energy from ambient vibrations to low power required systems such as wireless and sensor for purpose of non-battery utilization, which leads to reduce production of global warming gases, has become increasingly interested. Due to rather low power output of the piezoelectric transducer and relatively high cost per watt of piezoelectric materials, simulation and performance analysis to find maximum power point of the variation of its parameters are considered. This paper presents the modeling of Lead Zirconate Titanate (PZT) employed in low frequency application using mechanical force and simulated in Capture OrCAD environment. The parametric studies are also carried out in order to identify the point that provides the highest performance allowing making decision for choosing proper piezoelectric material characteristics to match to specific tasks.
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An experimental setup investigation to study characteristics of fault on transmission system
(2015-01-01)
Yindeesap, P.
;
Ngaopitakkul, A.
;
Pothisarn, C.
;
Jettanasen, C.
This paper proposes the experimental setup for studying the characteristics of fault caused by balance and unbalance on a transmission system. The parameters of transmission system (inductance and capacitance) are calculated based on forms of transmission tower, size of conductor, types of conductor and arrangement of transmission line and, they normalized to obtain the values in the π- equivalent circuit model at voltage level of 400 V. In addition, the ATP/EMTP is used to compare the simulated results with the experimental setup in order to show the advantage of the experimental setup. The obtained results show that the similarity between the two waveforms. The experimental setup will be useful in the development of short-circuit protection system in laboratory.
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A study an impact of daylight with period time on illuminance and uniformity for building
(2015-01-01)
Sripramong, S.
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Ananwattanaporn, S.
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Ngaopitakkul, A.
;
Jettanasen, C.
The daylight can be applied for lighting system in building to reduce energy consumption. Although the illuminance on the task area can be increased using the daylight but various factors must be taken into account. This research aims to study an impact of illuminance with daylight in term of each time period. The illuminance is calculated with daylight function in DIALux program. In addition, the fluorescent T5 tube lamp is used in simulation. The case study room without daylight (base case) is compared, in term of illuminance, with the case study room with daylight of each time period. The obtained results show that the daylight can increase the illuminance in the building so the lighting system in many modern buildings has applied daylight in order to achieve specific result of energy savings. The obtained results are useful for design of the interior lighting system.
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Mitigation of conducted and radiated EMI generation in high-frequency switching devices
(2015-01-01)
Sripodok, P.
;
Jettanasen, C.
The purpose of this paper is to investigate the electromagnetic interference (EMI) propagation paths and how to mitigate these generated high-frequency noises in high-frequency switching devices. Both conducted and radiated EMI can be produced when the devices are in operation. This results in restriction of power electronic devices' evolution. In order to effectively reduce EMI generation or overcome EMI problems, an Electromagnetic Compatibility (EMC) regulation should be applied. The conformity to the standard will guarantee the performance and the compatibility of the electrical/electronic devices/equipments to be employed or installed in the sensitive electromagnetic environment. The EMC standard is defined in the frequency range of ISO kHz to 1 GHz: 150 kHz to 30 MHz for conducted emission measurement and 30 MHz to 1GHz for radiated emission one. A switching device connecting to tuner kit (FM radio) is herein focused as an EMI source. The generated noises will be reduced by using grounding and shielding methods. The obtained results will be compared with an EMC standard (EN55022 class B) in order to reveal the effectiveness of the applied EMI mitigation techniques. The analysis and experimental results finally show that the conducted emission can be diminished by using multi-point grounding whereas the radiated emission is effectively reduced by using single-point grounding and shielding, in particular at high frequencies.
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Practical design of a passive EMI filter for reduction of EMI generation
(2015-01-01)
Jiraprasertwong, J.
;
Jettanasen, C.
Electromagnetic Interference (EMI) usually generated by a power converter can disturb or damage nearby sensitive electrical/electronic devices/equipment. The use of EMI filter inserted in the considered system is a classical technique for EMI reduction. In order to spend less time and have low cost, this paper proposes a user interface for practical EMI filter design. This interface is easy to use and able to rapidly find out the filter component values. The principle of this design is based on calculation from electromagnetic noises measured by spectrum analyzer, then the algorithm tries to find the cut-off frequency of the filter in order to obtain the attenuated noises respecting to an applied Electromagnetic Compatibility (EMC) standard. The performance of this practical EMI filter design is guaranteed by the real EMI emission measurement. Moreover, this user interface can be useful and used for other power converters, switching devices or EMI sources. Finally, it will reduce time consuming and cost when performing EMC testing in the real work.
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Improvement to reduce training time of back-propagation neural networks for discrimination between external short circuit and internal winding fault
(2014-11-05)
Bunjongjit, S.
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Ngaopitakkul, A.
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Pothisarn, C.
;
Jettanasen, C.
This paper proposes the improvement technique to reduce training time of back-propagation neural network. The decision algorithm based on the hybrid of discrete wavelet transform (DWT) and back-propagation neural network (BPNN) has been proposed to classify between external fault and internal fault in power transformer. The DWT is employed to decompose high frequency component of post-fault differential current signals and used as an input pattern for the training process of a neural network in a decision algorithm with a use of the BPNN. The proposed technique is compared with conventional training process of BPNN in terms of average accuracy and training time process. The obtained results show that the proposed technique can reduce of training process duration time and is very effective in classifying between external fault and internal fault in power transformer with satisfactory accuracy.

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