จำนวน Repository ( 255 )
Compensation of low frequency oscillation on power system using flexible ac transmission systems devices
This paper presents a study of low-frequency oscillations in compensated electric power systems with Flexible AC Transmission System of the power system frequency using PSAT Tool box To assist in the analysis of the stability of the system When the power transients in power systems is simulated By using standard IEEE 14 bus system as a case study. The Equipment that used to control the swing frequency of the is a flexible electrical power control devices or FACTS are two kinds of serial and parallel. The analysis showed that two models are compared with the time (Time Domain) and see the effect of the Eigen (Eigen Value) of the simulation results show work to see that controls are electrical flexible compensation. of low frequency oscillations in power systems in acceptable coordinates
Grounding system analysis for reduce voltage sag in distribution system
The fault in a power distribution system disturbs the power dispatch under normal conditions therefore decreases the quality of the electric power. The single line to ground fault is an asymmetric fault that may have a high percentage chance to happen. The kind of fault changes power and voltage dramatically. The size of the phase voltage decreases which affect the economic damage of the system. This paper presents an analysis of grounding systems to reduce voltage drop in a power distribution system by using the technical analysis system in case of one phase to ground fault. The objective is to minimize voltage drop for users using the simulation with single line to ground fault in distribution system voltage level at 22 kV PEA’s test system. The simulation utilizes the EMTDC-PSCAD program. The results show that the grounding method can reduce the voltage drop and reduce the damage of the economic system
The educational successful in data structure and algorithm subject for information system field’s student Rajamangala University of Technology Isan
This applied research want to study the factors affecting the student‘ learning achievement instudying Data Structure and Algorithm. The samples were selected by stratified random sampling 93 students from 121 students who studied in semester 2/2009 by using questionnaire. The statistics used were descriptive statisticst-testOne way ANOVAPearson correlation and multiple regression at the significance level of 0.05. The findings revealed that the mean of grade point average was 2.69 their average midterm scores were 22.47 out of 35. The successful were grade point averagefair expectation of knowledgeand future application.The factors affecting student’s achievementwere basic knowledge of programmingmidterm scores studied resource and facilities. In addition the 2 year programme’ average midterm scores were higher than the 4 year programme ranging from 1.11 to 5.34 at the significance level of 0.05. The forecasting equation for learning achievement is
A study of the efficiency of transportation system for tourism in koh sichang chonburi province
This objective of this research was to study the personal factors and efficiency of transportation system for tourism in Koh Sichang Chonburi Province. The research samples contained the person who related in transportation for the tourism in Koh Sichang Chonburi which were tourists tourism transport entrepreneurs and government departments totaling 412 samples. The data was collected using questionnaires and convenience sampling methodology. After collecting data those were analyzed by using descriptive statistics and inferential statistics. he result of the research has shown that tourists are mostly female age between 25-40 years. The tabulation of the mean scores shows the moderate agreement. Also it is found that sample group whose gender and age are different will have no different. Person who related in transportation for the tourism are different will have different attitudes toward the Efficiency of Transportation System for Tourism in Koh Sichang Chonburi Province
Mathematical modelling for design the control system of a liquid
This paper presents a mathematical modelling for design the control system of a liquid. The system are consists of one and two tanks of a liquid. To confirm the achieved mathematical modelling is used to design P PI PD and PID controller in the frequency domain. The experimental results are indicated as the following. An one tank of a liquid controlling The controller can be control the liquid level to set point with in 100s. In the case of a disturbance occurs in the system it is perform by drain a liquid. As same as the controller it can be control the liquid level into the steady state. In the part of the liquid control this is the interaction between two tanks. The experimental results of the system operation the controller can be control the liquid into the set point both occur disturbance and without disturbance respectively