الفهرس | Only 14 pages are availabe for public view |
Abstract In this thesis, a technique for high impedance fault detection is introduced. In this technique a discrimination between the high impedance fault and the switching conditions is achieved. This is being possible by employing the change in the third harmonic current / voltage magnitude in conjunction with the conventional wavelet algorithm. Performance of the proposed technique is examined via a detailed simulation of a typical medium voltage redial distribution feeder. In this simulation the high impedance fault is expressed by an arc model. The concept of the discrimination is based on that the switching condition does not contain changes in the zero sequence third harmonic magnitude. However, for high impedance arcing fault, there will be a remarkable change in the third harmonic current or voltage magnitude. The simulation conducted using MATLAB for different fault cases reveals that all fault cases are detected using the proposed technique. A novel fault location algorithm is also presented in this thesis. In this algorithm the percentage error is substantially decreased, particularly for high impedance fault. The accuracy at the algorithm is compared with four reported conventional fault location algorithms. |