| Summary: | 碩士 === 國立臺灣科技大學 === 電機工程系 === 88 === In this thesis, grounding safety problems of low-voltage equipments are studied to analyze the characteristic of the ground potential rises due to grounding faults. Thus, practical solutions can be obtained to prevent workers from electric-shock accidents. Also, the potential coupling from lighting ground to equipment ground is analyzed. For those studies, the domestic and foreign regulations and techniques related to grounding are first compared, which include CNS, Indoor and Outdoor Conduit Unit Rules, NEC, JIS, IEEE, and IEC. Then, the finite element method program, FLUX3D, has been applied to analyze the distribution of the ground potential rises caused by a mental house and different grounding systems including the ground rod, mental plate, etc. during the ground faults. Those FLUX3D results can be then employed to evaluate whether the touch voltage and step voltage satisfy the body safety regulations or not. Besides, the MALT module of the grounding safety software, CDEGS, has been to analyze the grounding safety problems of the ground grids at low frequencies. Also, by injecting lighting current at different frequencies into the ground system, the MALZ module of CDEGS has been applied to analyze the potential coupling to the ground systems of the equipments and oil tank. Those results may be used to study the damage and interference caused by the lighting.
|
|---|
