Talian penghantaran dan pengedaran mengalami kegagalan akibat ribut, kilat, salji, hujan beku, kerosakan penebat, litar pintas yang disebabkan oleh burung dan lain-lain objek luaran. Di kebanyakan kes, kegagalan elektrik memanifestasikan kerosakan mekanikal, yang perlu dibaiki sebelum kembali dalam perkhidmatan. Sekiranya kegagalan berlaku pada talian penghantaran, ia adalah penting untuk mencari tempat berlakunya kerosakan. Krew penyelenggaraan dapat tiba di tempat berlakunya kegagalan dengan cepat and membaikinya. Jika tempat berlaku kegagalan dapat dikesan dengan cepat, ia dapat menanggalkan kegagalan, mengurangkan kos, meningkatkan reliabiliti dan mengurangkan sumber ekonomi. Kegagalan talian penghantaran boleh dikategorikan kepada Kegagalan tiga fasa, talian tunggal ke bumi, Kembar talian ke bumi dan talian ke talian. Apabila kegagalan berlaku, kita perlu mempertimbangkan rangkaian jujukan positif dan negatif, dan juga rangkaian jujukan sifar. Kaedah penentu kegagalan berdasarkan impedan adalah paling biasa digunakan kerana mudah dan menjimatkan kos. Dalam laporan ini, tiga kaedah impedan satu-terminal teknik dianalysiskan untuk membandingkan kecekapan dalam menentukan kegagalan. Selain daripada lokasi kegagalan di talian penghantaran, penentu kegagalan di bas juga direkaciptakan. Ini disebabkan kegagalan di bas-bas boleh menghasilkan masalah kepada sistem penghantaran elektrik. MATLAB program dibangunkan untuk menentukan lokasi kegagalan. Program ini dapat mencari lokasi kegagalan dan ketidakjituan pada talian penghantaran dengan adanya impedan, sumber voltan, sumber arus dan arus kegagalan dalam bentuk magnitud dan dajah. Teknik menentukan kegagalan boleh dipertingkatkan kepada talian sederhana dan panjang serta bas-bas yang lebih rumit dalam sistem penghantaran elektrik.
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Transmission and distribution lines experiences faults due to storms, lightning, snow, freezing rain, insulation breakdown and, short circuits caused by birds and other external objects. In most cases, electrical faults manifest in mechanical damage, which must be repaired before returning to service. When the fault is at the transmission line, a precise fault locator must be able to detect the fault so the maintenance team can reach and fix the problem quickly. A good fault locator may help to remove the fault quickly, save cost, improve in system reliability and decrease in economic damages. Transmission line faults can be categorized to Balanced three phased, Single Line to Ground, Double Line to Ground, and Line to Line Faults. When the unbalanced faults occur, we need to consider the symmetrically balanced positive-sequence and negative-sequence set, and also a single-phased zero-sequence set parameters. Impedance-based fault location methods are the most commonly used in practice for reason of simplicity and low building cost. In this report, three methods of single-terminal impedance-based fault location techniques are analyzed to compare their efficiency. The above four categories are considered in this project. Beside fault location to determine the length on the transmission line, a fault locator for fault buses is developed because fault bus is also a problem to the power system. A MATLAB program for each category/case is developed and the program can be used to calculate the error on the transmission line using all the information given including line impedance, voltage source, current source, and fault current in magnitude and degree. Fault location can be further improved into medium and long transmission line and more buses in the power transmission networks.
Design of fault locators for transmission lines using matlab simulation / Ho Chee Wai