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รายการ All EE Papers(2554-02-18) Ajarn EEรายการ All ME Papers(SPU Knowledge Bank, 2554-02-18) Ajarn MEรายการ Application of Distributed Slack Bus Power Flow to Competitive Environments(Proceeding of the Australasian University Power Engineering Conference 2007, 2550-12-09) Keerati ChayakulkheereeThis paper presents the mathematical model of distributed slack bus power flow (DSPF) program and its application to competitive electricity supply industry (ESI). The advantage of DSPF is its ability to compute the frequency deviation when the ACE is treated as fixed value. It can represent the automatic generation controls (AGC) for maintaining nominal frequency. More specifically, the proposed method can diversify the power imbalance to voltage controlled buses in the system via participation factor. Therefore, the AGC of the generators can be incorporated in the analysis. The participation factors of the generators are obtained by the weighted average of AGC accepted quantities in ancillary services market. The results shows that the proposed method can satisfactory represent the system behaviour that all generators are response to power imbalance. In addition, the proposed method results in the better justified AGC setting in competitive electricity market than that of using single slack bus power flow. The DSPF is tested with the IEEE 30 bus system and compared to single slack bus power flow solution. Numerical results shown that the method can effectively represent the generation control characteristics to the power flow model and potentially be applied to simulate the competitive electricity markets.รายการ Distributed Slack Bus Power Flow Part I: Mathematical Model and Framework(The 30th Electrical Engineering Conference, 2550-10-25) Keerati ChayakulkheereeThis paper presents the mathematical model and test example of distributed slack bus power flow (DSPF) program. The method can diversify the power imbalance to voltage controlled buses in the system via participation factor. Therefore, the automatic generation controls (AGC) of the generators can be incorporated in this power flow model. The DSPF is tested with the IEEE 30 bus system. Numerical results shown that the method can effectively represent the generation control characteristics to the power flow model and potentially be applied to the overcoming competitive electricity supply industry.รายการ Distributed Slack Bus Power Flow Part II: Prospect and Challenge for Competitive Environments(The 30th Electrical Engineering Conference, 2550-10-25) Keerati ChayakulkheereeThis paper introduces an application of distributed slack bus power flow to competitive electricity supply industry (ESI). The participation factors of the generators are obtained by the weighted average of AGC accepted quantities in the ancillary services market. The results shows that the proposed method can satisfactory represent the system behavior that all generators are response to power imbalance. In addition, the proposed method results in the better justified AGC setting in competitive electricity market than that of using single slack bus power flow.รายการ Economic of Power System Reliability [Presentation](2551-02-24T04:30:40Z) Keerati Chayakulkheereeรายการ Flux/underfill Compatibility Study for Flip-chip Assembly Process(IACSIT Press, Singapore, 2554-05-28) Phuthanate Phoosekieaw and Sanya KhunkhaoThe rapid uptake of flip-chip technology within the electronics industry due to their better thermal performance, smaller size, lower profile, light weight, and higher input/output density, the solder joints together with underfill in flip chip package serve as a mechanical mechanism for resisting the thermal deformation induced by the coefficient of thermal expansion (CTE) mismatch between silicon die and substrate. underfill materials are employed in flip-chip assemblies to enhance solder joint reliability performance. The adhesion of underfills with solders is important to the integrity of the flip-chip structure. The effect of temperature and humidity aging as well as flux residue on adhesion strength was also investigated.รายการ Improved Line Imbalance of Single-Switch Converter by Double - Switch Converter for Common-Mode Noise Reduction(EECON2007, 2550-10-25) Boonpirom NimitThis paper aims to improve the system imbalance of the single - switch converters by employing the double -switch converter. The main objective is to analyze the cause of common mode noise generating in case of system imbalance and employing the double-switch converter for the common mode noise reduction. As the results, the ringing voltage and stress voltage of switching device are reduced. Finally, the experimental results in DC motor drive show the effectively improvement both time domain and frequency domain.รายการ An Investigation Study on Fuzzy Line Flow Limit Constraints in Competitive Electricity Markets(The 30th Electrical Engineering Conference, 2550-10-25) Keerati ChayakulkheereeIn this paper, the fuzzy set theory is applied to model the soft constraint limits. The fuzzy constrained optimal dispatch is formulated as a fuzzy optimization problem and converted into a crisp optimization problem. An efficient successive linear programming method is then modified to solve the new problem. Numerical test results on IEEE 30-bus system show that the fuzzy constrained method could give a good trade-off between reducing generation cost and satisfying constraints, and produce more realistic generation schedules when a feasible solution cannot be obtained by using the crisp OPF.รายการ Multi-Objective Optimal Power Flow Considering System Emissions and Fuzzy Constraints(Proceeding of International Conference on Sustainable Development: Challenges and Opportunities for the Greater Mekong Subregion, 2550-12-12) Keerati ChayakulkheereeThis paper proposes a fuzzy multi-objective optimal real power flow (FMOPF) with transmission line limit and transformer loading constraints. In the proposed FMOPF algorithm, the total system operating cost, total system SO2, NOx, and CO2 emissions fuzzy minimization objectives are solved simultaneously considering fuzzy line flow constraints, using fuzzy linear programming (FLP). The proposed FMOPF is tested with the IEEE 30 bus system. The simulation results shown that the proposed FMOPF can efficiently and effectively trade off among total system operating cost and total system SO2, NOx, and CO2 emissions.รายการ Network and Generator Constrained Economic Dispatch Using Hybrid PSO-QP Algorithm(Proceeding of the 2006 ECTI Conference, 2549-05-10) Keerati ChayakulkheereeThis paper proposes a hybrid particle swarm optimization (PSO) and quadratic programming (QP) algorithm for power system economic dispatch (ED) with transmission line limit and transformer loading and generator prohibited operating zones constraints. In the proposed PSO-QP-ED algorithm, the sets of real power generation at generator bus are used as particles in the PSO. The quadratic programming ED with transmission line limit and transformer loading constrained is performed every generation to obtain the best solution of each population search. The proposed PSO-QP-ED is tested with the IEEE 30 bus system and compared to the PSO-ED. The proposed PSO-QP-ED results in more probability to obtain global minimum total system operating cost in the constrained ED than the PSOED considering generator prohibited operating zones constraints.รายการ A New Simple Method for Post-tension Strands Friction Coefficient Measurement(Suranaree University of Technology, 2557-08-27) Chatr SuchindaThis article describes a new simple method of measuring the friction coefficients and their values from construction sites in Thailand. The friction coefficients between prestressing strands and their conduits are related to both wobble and curvature. The method requires both measured jacking force and elongation of each strand so the average tensile force along the entire length can be determined from non-linear stress-strain relationship. Then, the total length and total curvature of each strand were calculated from shop drawing to simulate the friction calculation in the design process. The determined friction coefficients will include the effect due to misplace of the conduit layouts from shop drawings. From the experimental measurement of 624 bonded system strands with spiral galvanized metal sheet conduits in post-tensioned slabs structures from two construction sites with two different post-tensioned sub-contractors, the wobble coefficient is 0.0035 per foot and the curvature coefficient is 0.536 per radian for sub-contractor 1 and the wobble coefficient is 0.0040 per foot and the curvature coefficient is 0.578 per radian for sub-contractor 2. The friction coefficients significantly differ than those recommended by ACI318-11 and BS8110-1997 standards.รายการ Optical profiling on lateral spreading of spacecharge-(Proceedings of the 2007 Electrical Engineering/Electronics,, 2550-05-09) Sanya KhunkhaoOptical profiling on lateral spreading of space-chargeregion properties of Schottky-barrier metal-semiconductormetal (MSM) structures have been investigated experimentally. Making use of a planar molybdenum/n-type silicon /molybdenum (Mo/n-Si/Mo) MSM structure with a wide electrode separation, one-dimensional (1D) profiling of optical– beam intensity distribution from a helium-neon (He-Ne) laser was carried out. It was also confirmed that, in addition to existing photosensing function, the sensitivity (output photocurrent) of such a structure could be controlled by an applying bias via lateral spreading of the surface space-chargeregion (SCR) at the side of the Schottky-junction reversebiased.รายการ Optical-beam profiling by bias-controlled metal-semiconductor-metal structures(APAC-SILICIDE 2006, 2549-07-29) Sanya KhunkhaoRecently we have shown experimentally that a planar metalsemiconductor- metal(MSM) structure having a wide separation between the two metal electrodes exhibits not only the function of a basic optical sensor but also optical sensitivity field-controllable by the bias applied [I]. In this study, we present the experimental results of onedimensional (ID) optical-beam profiling properties of an MSM structure as its application. To our knowledge, no study has appeared on such an application of planar MSM structures.รายการ Optimal Power Flow Considering Non-Linear Fuzzy Network and Generator Ramprate Constrained(Internation Energy Jurnal, Regional Energy Resource Information Center, 2550-06) Keerati ChayakulkheereeThis paper proposes a fuzzy constrained optimal power flow (FCOPF) algorithm with non-linear fuzzy network and generator ramprate limit constraints. The problem is decomposed into total fuel cost fuzzy minimization subproblem and total real power loss fuzzy minimization subproblem, which are solved by fuzzy linear programming (FLP). In the total fuel cost fuzzy minimization subproblem, the line flow and transformer loading limits and the generator ramprate limits are treated as fuzzy constraints. Whereas, in the total real power loss fuzzy minimization subproblem, the bus voltage magnitude limits are treated as fuzzy constraints. The non-linear S-shape membership function is used for representing soft characteristic of fuzzy constraints. The proposed FCOPF algorithm is tested on the IEEE 30 bus test system with and without lines outage cases. The results show that the fuzzy constrained optimal power flow algorithm can successfully trade off among total fuel cost, line flow and transformer loading and generator ramprate in the total fuel cost fuzzy minimization subproblem and between total real power loss and bus voltage magnitude in the total real power loss fuzzy minimization subproblem.รายการ Optimal Scheduling of Limited Energy Units Using Deconvolution Technique: A Case Study of Hydro Power Generation in Thailand(The 27th Electrical Engineering Conference, 2547-11-11) Keerati ChayakulkheereeThis paper investigates a practical application of deconvolution technique base optimal scheduling of limited energy units (LEUs). The computer program has been developed so that the probabilities of unit outages are taken into account by capacity model building and deconvolution technique is used to determine the optimal scheduling of LEUs. The program has been tested with the equivalent Thai power system with 110 power generating units, including 16 LEUs (hydro plants). The results shows that the deconvolution technique based optimal LEUs scheduling can dispatch all of daily energy specified at the optimal condition leading to the lower daily operating cost than that of scheduling without deconvolution calculation. The method can effectively associate the unit commitment problem as a preliminary scheduling of LEUs.รายการ Photocurrent enhancement in silicon-based planar metal-semiconductor-metal(2549-11-09) Sanya Khunkhaoผลการเพิ่มขึ้นของกระแสแสงแบบตรง (DC photocurrent) ซึ่งเป็น สมบัติของตัวตรวจจับทางแสงโครงสร้างเชิงราบ โลหะ-สารกึ่งตัวนำ-โลหะ จากรอยต่อแบบช็อตต์คีย์สองรอยต่อเชิงราบระหว่างโมลิบดีนัม/ซิลิคอน (Mo/Si) บนฐานรองซิลิคอนชนิดเอ็น (n-type)มีสภาพความต้านทาน 9-12 Ωcm โดยมีระยะห่างระหว่างขั้วไฟฟ้าเท่ากับ 20 μm การวัดสมบัติระหว่าง กระแสกับแรงดันภายใต้ความเข้มแสงย่าน visible light แสดงถึงการเพิ่มขึ้น ในกระแสแสงอย่างรวดเร็วที่แรงดันไบอัสสูง และผลจากสมบัติของกระแส กับแรงดันที่ขึ้นกับอุณหภูมิ (Temperature dependence) และการวัดสัญญาณ รบกวน พบว่ากระแสแสงนั้นมีการเพิ่มขึ้นเนื่องจากผลของการทวีคูณแบบอะ วาลันซ์ จากประจุพาหะที่เกิดขึ้นที่ภายในรอยต่อช็อตต์คีย์ที่ขั้วไฟฟ้าด้านที่ ได้รับการไบอัสย้อนกลับ นอกจากนั้นจากการทดสอบวัดการตอบสนองของ สัญญาณไฟฟ้าแบบสลับที่ความถี่ต่ำ 10kHz และ 50kHz พบว่าเฟคเตอร์ของ การทวีคูณ(Multiplication factor) มีมากเกินกว่า 100 ที่ความถี่ 10kHz และ 30 ที่ความถี่ 50kHzรายการ Photoinduced on laterally spreading of space-chargeregion(Proceedings of the 2006 Electrical Engineering/ Electronics, Computer,, 2549-05-10) Sanya Khunkhaoรายการ Powerpoint วิชา CEG101 วิศวกรโครงสร้าง(SPU, 2552-02-23) ฉัตร สุจินดารายการ Shot noise due to carrier generation in planar metal-semiconductor-metal optical sensors structures(International Conference on Applied Science: ICAS 2006, 2549-11-05) Sanya KhunkhaoLow frequency 3-100 kHz shot noise (white noise) emerging from photoinduced current in Mo/n-Si/Mo structures leaving undepleted region has been observed under different bias and optical intensity conditions. The measurements revealed that the current noise observed depends not only on the illumination intensity levels but also on bias voltage. The current noise observed is expressed as 2()2SqIωΓ= and analyzed, where I and2Γis the average current and noise factor, respectively. The measurements reveal that2Γhas strong bias dependence, lying to about unity corresponding to simple shot noise. Such experimental results are explained, stating that the reduction of crosscorrelation between drift and diffusion currents and autocorrelation of drift current component determining the level of noise occurs with decrease in SCR width bias-dependent. To explain the behavior of observed noise more properly, we propose, in addition to the mechanisms above, that the reduction in autocorrelation effect of each current component plays an important role to decrease the relevant noise to such extremely low levels.
