Recently, a lightning surge is recognized as one of the biggest risks to the society. If the surges induced by lightning invade into low voltage distribution lines, there might be a possibility of giving some severe d...Recently, a lightning surge is recognized as one of the biggest risks to the society. If the surges induced by lightning invade into low voltage distribution lines, there might be a possibility of giving some severe damages to the systems. Therefore, it is necessary to examine these induced phenomena. FDTD （finite difference time domain） method which treats objects as three-dimensional solid circuits is applied to analyze these induced phenomena. VSTL （Virtual Surge Test Lab.） is the surge analysis simulation program using FDTD method. In this paper, the lightning induced phenomena on the low voltage distribution line in the house are analyzed by using VSTL. In this paper, investigation results about induced surge when a lightning struck the point nearby the house, and about a suppressing effect of surges by comparing the results of analysis with and without SPD （surge protective device） are shown. As a result, it is confirmed that SPD is effective for suppressing lightning surge.展开更多
In the period 2003-2011, lightning over-voltages accounted for about 47% of the total number of distribution transformer failures observed in the service area ofAES Sul, a power company that operates in the state of R...In the period 2003-2011, lightning over-voltages accounted for about 47% of the total number of distribution transformer failures observed in the service area ofAES Sul, a power company that operates in the state of Rio Grande doSul, in South Brazil. This paper presents the results of an investigation on the influence of the distance between transformer and MV arresters on the surges at the transformer windings caused by direct strikes to the MV network. The analysis, performed through simulations using the Alternative Transients Program, shows that in general higher voltages are produced by subsequent strokes. Although in relation to the primary side the surges transferred to the secondary are much less affected by the distance between transformers and primary arresters, such distance should always be kept as short as possible in order to reduce the probability of occurrence of transformer failures due to over-voltages at the MV bushings.展开更多
文摘Recently, a lightning surge is recognized as one of the biggest risks to the society. If the surges induced by lightning invade into low voltage distribution lines, there might be a possibility of giving some severe damages to the systems. Therefore, it is necessary to examine these induced phenomena. FDTD （finite difference time domain） method which treats objects as three-dimensional solid circuits is applied to analyze these induced phenomena. VSTL （Virtual Surge Test Lab.） is the surge analysis simulation program using FDTD method. In this paper, the lightning induced phenomena on the low voltage distribution line in the house are analyzed by using VSTL. In this paper, investigation results about induced surge when a lightning struck the point nearby the house, and about a suppressing effect of surges by comparing the results of analysis with and without SPD （surge protective device） are shown. As a result, it is confirmed that SPD is effective for suppressing lightning surge.
文摘In the period 2003-2011, lightning over-voltages accounted for about 47% of the total number of distribution transformer failures observed in the service area ofAES Sul, a power company that operates in the state of Rio Grande doSul, in South Brazil. This paper presents the results of an investigation on the influence of the distance between transformer and MV arresters on the surges at the transformer windings caused by direct strikes to the MV network. The analysis, performed through simulations using the Alternative Transients Program, shows that in general higher voltages are produced by subsequent strokes. Although in relation to the primary side the surges transferred to the secondary are much less affected by the distance between transformers and primary arresters, such distance should always be kept as short as possible in order to reduce the probability of occurrence of transformer failures due to over-voltages at the MV bushings.
