The Effect Transmission Line Load Variation on Incoming and Reflection Waves

• Main Authors: Tang Ta-Hui, 湯達輝
• Other Authors: Kao Wen-Hsiu
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/81869851465631488897

碩士 === 國立臺北科技大學 === 電機工程系碩士班 === 90 === ABSTRACT Electric power system in transmission wire demands safety,reliability,small-attenuation.Poewr system requires to maintain in good maneuver iany circumstance,even part of set is out of order.So any feeder wire in mal-function or load in trannsient state can be found and the problem should be solved immediately.Electric wave proceeding in wire is various with load causing wave reflection,data and angle variation.Such as load is in open-state or in short-state,even load is a solid-capacitance or a solid-industance.Or the value of industance and capaitance is changed.All of them will result transient-state.So the transient state analysis is very important. Computer becomes popular recently .It has an influence on power system analysis and design. We can use personal computer to analyze steady-state or transient-state of power system.Computer also can afford us information with ability of simulation and wave-form response in time.So technical professor puts computer knowledge in the course to avoid experimental mistake. This study uses software MATLAB to simulate and to analyze the touble-shooting of load.If an incoming wave in transmission wire is in the following state,such as load in short state ,open state in solid-capacitance,solid-inducatance,in series reductance,all the state will induce a reflection wave,a standing wave and data,angle variation.The results are as follow:(1)The more the reflection data is,the larger the reflection wave becomes.(2)If load redutance >>wire redutance shown circuit open induces reflection data >0,wave-form upward.(3)If load redutance <<wire redutance shown circuit short induces reflection data <0,wave-form downward.(4)If wire terminal is in open-state redutance = induces reflection data =1,incoming wave and reflection wave are in the same pattern.(5)If wire terminal is in short-state,redutance=0 induces reflection data =-1,incoming wave and reflection wave have difference.(6)If circuit is in normal condition,redutance <Z< induce reflection data between —1 and 1.(7)If load is a solid-capacitance,capaitance value is between 0.001Fara and 100 Fara,induces reflection data remaining the same,but reflection angle data is shifted smaller from 0.1060 to 0.011.(8)If load is a solid-indutance,indutance value is between 0.001 Henry and 100 Henry,induces reflection data remaining the same,but reflection angle data is shifted smaller from 0.0241 to 0.0029. The study is to find a transmisson wire in load variation induces a shifting reflection wave and its situation.