This thesis proposes technical performance evaluation and economic decence for the combination of harmonic correction devices in Industry. Currently an electronic device is popularly applied in power network. Although it is a higher performance device than the existing device it still causes the power quality issues and then network failure. Especially harmonic disturbance in the network it is a harmonic source that generates harmonic current into the network. Many types and solutions are available in the present time therefore the suitable and optimal financial solution must be considered. A network model for the analysis of harmonic correction devices suitable solutions and optimal financial has been established in the simulation software that bases on the power and Break Even Point (BEP) equations. The results of analysis shown that the performance of harmonic correction devices suitable solution and BEP of investment in match to the using of a detuned filter bank and an active harmonic filter (case 8) thus these information will be valued for the end-user.

This thesis presents the Power Quality (PQ) analysis of solar power plant 1MW and economic impacts in the distribution power networks. The case study focuses on the penalty fee (fine) from consume the reactive power less than the limit of the Provincial Electricity Authority (PEA) of Thailand. The fine have been charged up to 900000 baht per year. Therefore the thesis studies and purposes the possible solution by analysing the operating function of the inverter (supports reactive mode) installing the adjustable capacitor bank 1500kVar in the Medium Voltage (MV) level and lastly installing the adjustable capacitor bank 1500kVar in the Low Voltage (LV) level. The results shown that the possible solution that reduces the fine is installed the adjustable capacitor bank 1500kVar in the MV. The investment of this installation is cost 1800000 baht with the nominal operation over 10 years. The analysis of financial investment which bases on the Net Present Value (NPV) the Benefit-Cost ratio (B/C) the Pay Back period (PB) is presented the NPV at 4902971 baht B/C 3.72 and PB 2 year (with the Internal Rate of Return; IRR 49.7 percent).

A distributed generation is a small-scale Installed in the customer density sources. The benefits of distributed energy resources is one example. To improve the reliability of power distribution system for the better. The increased reliability of power distribution system that is connected to the source of power distribution efficiency depends on the size of the supply and installation of power distribution are considered appropriate. To Evaluation the reliability in distribution system with the main purpose is to the minimization for customer interruption cost. The technique employed to minimization problem for customer interruption cost in solved by the developed tabu search algorithm together with reliability worth analysis that provide an indirect measure for cost implication associated with power failure. The developed methodology is tested with a distribution system of Roy Billinton Test System (RBTS) bus 2. Numerical results from the tests demonstrate that distributed generation can be used to promote economy and reliability of the distribution systems.

The objectives of this research were to 1) study attitudes and consumption behavior of clean food for health 2) compare personal factors with consumption behavior 3) compare personal factors with consumption attitudes and 4) study attitudes affecting consumption behavior. The sample group was the population of Bangkok Province. Used in the study: 740 people. The questionnaire was used as a research tool. The data were analyzed by frequency percentage mean standard deviation. T-value test Analysis of one-way ANOVA and multiple regression analysis. The research results were found that: attitudes towards the consumption of clean food for health during the Covid-19 epidemic situation was at a high level. Clean food for health consumption behavior during the Covid-19 epidemic situation was at a high level.Individual factors including gender education and status had different attitudes towards healthy food consumption. During the Covid-19 epidemic situation the difference was statistically significant at the .05 level Individual factors including gender education income occupation and status had different healthy clean food consumption behaviors during the Covid-19 epidemic with statistical significance at the .05 level. Attitudes had a statistically significant effect on healthy food consumption during the Covid-19 epidemic at .05 level.