Yoomak, Suntiti
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Item type:Publication, Feasibility Analysis of Different Energy Storage Systems for Solar Road Lighting Systems(2019-01-01); This paper investigates and analyses the feasibility of different energy storage systems for solar road lighting systems. The energy storage systems used in this paper are divided into two cases, namely, homogenous energy storage system [lead-acid (LA) batteries, lithium-ion (LI) batteries, and ultracapacitors (UCs)] and hybrid energy storage systems [lead-acid batteries with ultracapacitors (LA and UC) and lithium-ion batteries with ultracapacitors (LI and UC)]. Various solar power schemes are implemented based on stable and unstable solar irradiance conditions using an experimental setup. The economic analysis of the solar road lighting systems is performed based on the presented energy storage systems using discounted payback period (DPP), net present value (NPV), and internal rate of return (IRR). The installation of energy storage systems with individual and central systems for the solar road lighting system is also discussed. The results show that the LA batteries, LI batteries, and UCs yielded satisfactory active power quality for effective charging in all ranges of solar irradiance. However, the lifetimes of battery devices are degraded during dynamic active power charging. To overcome this shortcoming, hybrid energy storage systems are proposed using batteries and UCs. The use of LA batteries yields the lowest installation cost. However, the LI batteries offer the best economic viability in the long term. The cost of the UCs is too high to be used as an energy storage system for solar road lighting systems. However, the use of appropriate proportions of the UCs with batteries to reduce current and active power fluctuations for charging the batteries is economically viable. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Comparative study of lighting quality and power quality for LED and HPS luminaires in a roadway lighting system(2018-01-15); ; ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Optimisation of lighting quality and energy efficiency of LED luminaires in roadway lighting systems on different road surfaces(2018-04-01); Lighting quality plays an important role in determining the visual performance and visual comfort of the road user, which help keep driver alert. Lighting quality depends on various factors, such as mounting height, luminaire spacing, luminaires, overhang, boom angle, and road surface properties. The light that reflects from the road surface enters the eyes of the road user, and makes the road visible. However, prevailing conditions on the roadway determine the reflection properties of the road surface. This paper presents the analysis of lighting quality in different road surface conditions using the DIALux software. Dry and wet road surfaces are used to study lighting quality following the classifications of the International Commission on Illumination (CIE), where the lighting qualities of high-pressure sodium (HPS) and light-emitting diode (LED) luminaires are compared, based on a roadway without a traffic island. In addition, it presents the design of a roadway lighting system with optimised LED luminaires, by adjusting pole spacing and mounting height, ensuring the best installation in each classification of road surface. Thereafter, energy evaluations of different input powers of LED luminaires are discussed and compared with the HPS luminaire. Results indicate that the HPS luminaire can provide better average illuminance and average luminance values than LED luminaires, resulting in positive visual performance. However, LED luminaires can achieve better overall visual and comfort performances, including energy saving, due to their light distribution efficiency. For lighting quality in different road surface conditions, the wetter the road surface, the higher the lighting quality; because wet road surfaces cause alternating bright and dark areas on the road. This results in increased average luminance of the surface, and decreased longitudinal uniformity. Moreover, road surfaces with high average luminance coefficient, Q<inf>0</inf>, can accommodate larger pole spacing, reducing energy consumption. Using LED luminaires with lower or higher input power than the optimal power, however, result in higher energy consumption. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, The study of harmonic reduction in Light Emitting Diode (LED) roadway lighting system(2016-07-25); 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. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Solar water heating in residential building(2019-07-01); ; ; Songsukthawan, PanapongThe electrical consumption has been rapidly increased in the past few decades. However, environment concern and depleting of fossil fuel lead to raise of alternative energy. One of the applications for solar energy that has gain significant attention is solar thermal for watering heating that can replace electricity. This paper aims to presents feasibility on solar water heating for residential building in Thailand. The analysis has been done on both energy performance and economic perspective using RETscreen software and Bangkok, Thailand as case study location in order to verify the feasibility of solar water heating application in residential building. The result has shown the potential of solar water heating system application in residential building as a replacement to conventional electrical water heating. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Discrete wavelet transform and fuzzy logic algorithm for classification of fault type in underground cable(2018-01-01); ; ; This paper proposes the combination of discrete wavelet transform (DWT) and fuzzy logic to classify the fault type in underground distribution cable. The DWT is employed to decompose high frequency component from fault signal with the mother wavelet daubechies4 (db4). The maximum coefficients detail of DWT from phase A, B, C and zero sequence for post-fault current waveforms are considered as an input pattern of decision algorithm. Triangle-shaped S-shaped and Z-shaped membership function with maximum, medium, minimum, and zero are used to create a function for the input variable. Output variable of fuzzy are designated as values range 1 to 10 which corresponding with type of fault. The obtained average accuracy results shown that the proposed decision algorithm is able to classify the fault type with satisfactory accuracy. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Simulation study and experimental results for detection and classification of the transient capacitor inrush current using discrete wavelet transform and artificial intelligence(2018-01-01); ; This paper describes the combination of discrete wavelet transforms (DWT) and artificial intelligence (AI), which are efficient techniques to identify the type of inrush current, analyze the origin and possible cause on the capacitor bank switching. The experiment setup used to verify the proposed techniques can be detected and classified the transient inrush current from normal capacitor rated current. The discretewavelet transforms are used to detect and classify the inrush current. Then, output from wavelet is acted as input of fuzzy inference system for discriminating the type of switching transient inrush current. The proposed technique shows enhanced performance with a discrimination accuracy of 90.57%. Both simulation study and experimental results are quite satisfactory with providing the high accuracy and reliability which can be developed and implemented into a numerical overcurrent (50/51) and unbalanced current (60C) protection relay for an application of shunt capacitor bank protection in the future. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Feasibility analysis of different energy storage systems for solar road lighting systems(2019-05-01); This study investigates and analyses the feasibility of different energy storage systems for solar road lighting systems. The energy storage systems used in this study are divided into two cases, namely homogenous energy storage system (lead-acid (LA) batteries, lithium-ion (LI) batteries, and ultracapacitors (UCs)) and hybrid energy storage systems (leadacid batteries with ultracapacitors (LA and UC) and lithium-ion batteries with ultracapacitors (LI and UC)). Various solar power schemes are implemented based on stable and unstable solar irradiance conditions using an experimental setup. Economic analysis of the solar road lighting systems is performed based on the presented energy storage systems using discounted payback period (DPP), net present value (NPV), and internal rate of return (IRR). The installation of energy storage systems with individual and central systems for the solar road lighting system is also discussed. Results show that LA batteries, LI batteries, and UCs yielded satisfactory active power quality for effective charging in all ranges of solar irradiance. However, the lifetimes of battery devices are degraded during dynamic active power charging. To overcome this shortcoming, hybrid energy storage systems are proposed using batteries and UCs. The use of LA batteries yields the lowest installation cost. However, LI batteries offer the best economic viability in the long term. The cost of UCs is too high to be used as an energy storage system for solar road lighting systems. However, the use of appropriate proportions of UCs with batteries to reduce current and active power fluctuations for charging the batteries is economically viable. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Performance and economic evaluation of solar rooftop systems in different regions of Thailand(2019-12-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, The study of lighting quality of LED and HPS luminaires based on various road surface properties(2018-12-05); This paper presents analysis of lighting quality in different road surface conditions using the DIALux software. Dry and wet road surfaces are used to study lighting quality by following classifications of the International Commission on Illumination (CIE). Lighting quality of high pressure sodium (HPS) and light emitting diode (LED) luminaires are compared, based on roadway with a traffic island. Results indicate that the HPS luminaire can provide better average illuminance and average luminance values than the LED luminaire, resulting in positive visual performance. However, the LED luminaire can achieve visual and comfort performance including energy saving due to its light distribution efficiency. For lighting quality on different road surface conditions, the lighter dry road surface materials, the higher lighting quality. Wet road surfaces cause very bright areas on road surface alternating with large dark areas. It results in the average luminance of the surface increased while overall uniformity decreased.