At present,the regular inspection of power poles is just a visual inspection based on the inspector’s experience.Thus,overlook of the deteriorated poles can come off.In order to avoid an accident due to the overlook ...At present,the regular inspection of power poles is just a visual inspection based on the inspector’s experience.Thus,overlook of the deteriorated poles can come off.In order to avoid an accident due to the overlook of the deteriorated poles,the authors propose a simple and easy health monitoring method for power poles using‘i Pod’.Since the applicability of‘i Pod’as a vibration sensor in this purpose was not clear,it was examined in the following procedure.First,the authors proposed a tool to fix the‘i Pod’to a power pole,and the performance of‘i Pod’as a vibration measurement device was compared with a conventional acceleration sensor.As a result,it was confirmed that‘i Pod’could give almost the same response with the conventional sensor in terms of the observed predominant frequency.Next,vibration measurements were conducted at power poles in a field.As a result,the observed predominant frequency corresponded to the calculated 2nd natural frequency of power poles.Although some power poles were supported by some additional wires from the ground,the measurements were successful at almost all the sites.Hence,the authors confirmed that the‘i Pod’based health monitoring is possible.展开更多
The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, mos...The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, most of the power line networks are made of wooden supports and according to the Cameroon energy distribution company, wooden poles represent 32% of the causes of death linked to the state of the network. The company’s 2019 annual report indicates that 40,000 wooden poles were in critical condition and should be replaced. A significant number of mechanical failures affecting these supports have been observed. For example, on the HVA/LV power line “D17 Nko- abang” in Yaoundé in Cameroon, less than three years old, 10 (ten) cases of poles falling and/or breaking, due to their mechanical loading, were observed over a period of fewer than nine months, causing an average service stoppage for more than 11 hours and affecting an average of 3280 customers. These incidents lead to questions about how the supports are dimensioned and what load capacities they are designed to support. The aim of this work is, therefore, to suggest a method of dimensioning wooden poles hence reducing green- house gas emissions due to the deforestation by reducing the number of woo- den poles at risk to be replaced on Cameroon’s electricity distribution network. And more specifically, to reduce the number of mechanical failures affecting the wooden supports observed by analyzing the current wooden supports with their loads and to make proposals for improving the actual dimensioning me- thods. From the study carried out, it appears that 449 out of 845 supports, i.e., 53% needed to be replaced or monitored because they support the nominal forces ranging from 85% to 150% of their admissible limit and proposals have been made to improve their dimensioning.展开更多
基金The Electric Technology Research Foundation of Chugoku
文摘At present,the regular inspection of power poles is just a visual inspection based on the inspector’s experience.Thus,overlook of the deteriorated poles can come off.In order to avoid an accident due to the overlook of the deteriorated poles,the authors propose a simple and easy health monitoring method for power poles using‘i Pod’.Since the applicability of‘i Pod’as a vibration sensor in this purpose was not clear,it was examined in the following procedure.First,the authors proposed a tool to fix the‘i Pod’to a power pole,and the performance of‘i Pod’as a vibration measurement device was compared with a conventional acceleration sensor.As a result,it was confirmed that‘i Pod’could give almost the same response with the conventional sensor in terms of the observed predominant frequency.Next,vibration measurements were conducted at power poles in a field.As a result,the observed predominant frequency corresponded to the calculated 2nd natural frequency of power poles.Although some power poles were supported by some additional wires from the ground,the measurements were successful at almost all the sites.Hence,the authors confirmed that the‘i Pod’based health monitoring is possible.
文摘The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, most of the power line networks are made of wooden supports and according to the Cameroon energy distribution company, wooden poles represent 32% of the causes of death linked to the state of the network. The company’s 2019 annual report indicates that 40,000 wooden poles were in critical condition and should be replaced. A significant number of mechanical failures affecting these supports have been observed. For example, on the HVA/LV power line “D17 Nko- abang” in Yaoundé in Cameroon, less than three years old, 10 (ten) cases of poles falling and/or breaking, due to their mechanical loading, were observed over a period of fewer than nine months, causing an average service stoppage for more than 11 hours and affecting an average of 3280 customers. These incidents lead to questions about how the supports are dimensioned and what load capacities they are designed to support. The aim of this work is, therefore, to suggest a method of dimensioning wooden poles hence reducing green- house gas emissions due to the deforestation by reducing the number of woo- den poles at risk to be replaced on Cameroon’s electricity distribution network. And more specifically, to reduce the number of mechanical failures affecting the wooden supports observed by analyzing the current wooden supports with their loads and to make proposals for improving the actual dimensioning me- thods. From the study carried out, it appears that 449 out of 845 supports, i.e., 53% needed to be replaced or monitored because they support the nominal forces ranging from 85% to 150% of their admissible limit and proposals have been made to improve their dimensioning.
