Chow Chompoo-Inwai

Biomass power generation development in Thailand

The emerging global warming crisis results from carbon dioxide emission has drawn an attention about renewable energy all over the world. Thailand is a developing country located at the heart of Southeast Asia with almost 70 million of population as of 2008. The ESI structure under the government of Thailand has been managed by the Electricity Generating Authority of Thailand (EGAT), Metropolitan Electricity Authority (MEA), and Provincial Electricity Authority (PEA) for almost 50 years. 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. To achieve those goals, there are three strategic plans which are to import power from neighboring country, to promote the renewable power generation from the public power companies, and to have a variety on power generations resources. This paper discusses the biomass power generation development in Thailand. System overview processes and biomass fuel consumed for the electricity production process are also presented.

Analysis of Winding Temperature and Design of Distribution Transformer for Improving Short Circuit Withstand Capability under Renewable Generations Mixed Environment

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.

Performance comparisons between a singlechannel feedforward ANC system and a singlechannel feedback ANC system in a noisy-enviroment classroom

Adaptive or Active Noise Control System (ANC) is now widely used in many applications. The problem of interference or noise cancellation is one of the main focuses of the ANC solutions. In this paper, two classic ANC systems called a single-channel feedforward system and a single-channel feedback system will be simulated in MATLAB/Simulink environment for a demonstrative university classroom. This circumstance becomes an interesting issue since the aforementioned classroom is located right next to one of Asia Pacifics largest international airport in Bangkok City, Thailand. A very lousy-noise environment occurs when the time of airplane taking off and landing. Unfortunately, such a noisy environment happens almost every other minute on average. The main idea of this paper is trying to lower the level of the noise during those critical times in the classroom. Two simple ANC systems are brought into account here to see how they perform in resolving the problems in this particular circumstance. The least mean square (LMS) method is used for updating the weight vector in ANC control block diagram in order to achieve the optimal weight vector resulting in minimal errors. How to find bounds on the step size, how to estimate the rate of convergence and the steady-state errors of the proposed LMS method are also elaborated in this paper. The simulation results between two ANC systems will be presented in terms of noise attenuation capabilities and system performances. The discussions and the conclusions presented in this research paper will be used for further analysis to improve the selected ANC system performance before implementing in the real environment in a very near future to come.

Optical and electrical performance comparisons between high power LED and HMI studio lighting including the engineering economics analysis

Abstract A superior alternative to the conventional hydrargyrum medium-arc iodide (HMI) luminaires, high power light emitting diode (HP-LED) luminaires are increasingly being utilized in numerous modern lighting designs and applications. Specifically, this research is concerned with the comparative optical and electrical performance and engineering economic analysis of Fresnel-type HMI and HP-LED luminaires for studio lighting applications in the experiments conducted in a real studio environment. The findings revealed that, optically, the Correlated color temperature, luminous flux, luminous intensity and illuminance of the experimental HP-LED and HMI luminaires were comparable. The Color rendering index of the HP-LED was higher and its beam/spread output was more controllable. In the electrical aspect, the results showed that the HP-LED luminaire required significantly less power while producing lower %THDv and %THDi vis-à-vis the HMI counterpart. The payback period for the replacement of HP-LED luminaires was around 7 years and 7 months, which was shorter than the project life of 15 years. The commercial prospect of HP-LED luminaires is thus brighter as an excellent substitute for the conventional HMI luminaires in myriad applications, particularly in studio lighting for photography, cinematography, and broadcasting.

Design and Implementation of a smart monitoring system of a modern renewable energy micro-grid system using a low-cost data acquisition system and LabVIEWTM program

AbstractThis paper focuses on designing and implementing a prototype of smart monitoring system capable of doing multi functions i.e. monitoring, analysing and communicating with devices in a small micro-grid system. This research proposes the use of a combination between a low-cost data acquisition (NI compact DAQ) device and a commercially-used LabVIEW™ program in being a smart renewable monitoring and analysing system. The proposed set of equipment is capable of doing all the functions needed by utilities and users in the aforementioned micro-grid system. The proposed prototype is capable of measuring, monitoring and recording in both normal system operating conditions and when faults occurred. A number of power quality parameters that can be monitored and analysed are as follows: voltage (V), current (I), real power (P), reactive power (Q), apparent power (S), energy consumption (kWhr), power factor (PF), harmonics distortion (THDi and THDv), over/under voltage, sag as well as swell. Extensively in th...

Power flow monitoring and analysis for 24.6 MW at 6.9 kV bus Diesel Power Plant(DPP) using ETAP

It is obvious that power flow study and analysis are important to any kind of electrical power system engineering. The main purpose of this research paper is to study and analyze the power flow and system stability of the 24.6 MW Diesel Power Plant (DPP) which is the cement manufacture located in Cambodia at 6.9 kV bus using the commercial electrical transient analysis program called ETAP. Such a power plant comprises of four diesel generators with the generation capacity of 6,150 kW each. There are three outgoing feeders to different load type in various processes in this manufacture. Power flow study and analysis in this paper includes steady-state conditions to assure the voltage drop, voltage regulation, active and reactive power flow limits, transformer capabilities, cable sizing, and power factor at all connection points. Four cases of operations are in consideration in this research. All diesel engine generators assume to be operating in isochronous load sharing control. Nominal system voltage is at 6.6 kV plus/minus 5%. Maximum continuous operating voltage of the interest island system is 105% of 6.6 kV and minimum continuous operating voltage is 95% of 6.6 kV nominal system voltages. All motors loads are IEC standard design, typical motor load data from ETAP software database is used for this study. The simulation results will be shown here in this paper. The simulation results analysis, discussion and conclusion are also illustrated.

Engineering economic analysis between high power LED and hydrargyrum medium-arc iodide luminaries in studio lighting application

High Power Light Emitting Diode (HP-LED) luminaire is a rapidly evolving technology used for studio lighting application and replacement for the traditional Hydrargyrum Medium-Arc Iodide (HMI) luminaires which have significantly grown because of reducing energy consumption and also their efforts to reduce overall cost. In this research, an engineering economic analysis was made. Results indicated that the payback period (PBP) for the replacement of HP-LED luminaires was around seven years and seven months, which was shorter than the project life of fifteen years. The net present value (NPV) from the investment was about 60,491 baht with an internal rate of return (IRR) of 9.70 % and the benefit cost ratio (B/C ratio) was 1.82. In conclusion, the study found that the HP-LED luminaire replacement for HMI luminaire was identified as economically feasible.

A new distributed generation protection scheme in Thailand using direct transfer trip technique and Mirrored Bits Protocol

At present, most of the utility electrical power systems in Thailand are connected as a network. It is essential to gather many separated electrical power sources (from EGAT, PEA, MEA and private sectors i.e. IPP, SPP and VSPP) together to enhance the stability and reliability of Thailand’s power network. The appropriate protection scheme for a high voltage transmission system is indispensable. The current protection scheme that has long been used in most regions of Thailand’s network is a peer‐to‐peer protection scheme. Such a scheme has a big disadvantage when there is a fault at any point from only one power source in the network due to the lack of islanding mode of operation. For example, if there is a short circuit fault occurring in the region taken power from two sources, the protection relay will send out a signal to disconnect/cease the power from both ends, regardless of the fault locations. These circumstances happening quite often in many of Thailand’s networks and can cause a lot of damage fr...