Search

This study aims to monitor the sag of an overhead transmission line by proposing an IoT-based sag monitoring system, which can provide real-time sag information of a transmission line, preventing ground fault using an embedded three-axis accelerometer with IoT techniques. This reliable monitoring system directly measures sag-related parameters on and around a high voltage transmission line in real time. The measured results are highly similar with theoretical values. Moreover, the accuracy of the measured sag values has been verified by comparing the values with field measurements. These results confirm the high accuracy, reliability and durability of the proposed sag monitoring system. In addition, this study examines the measurement results obtained from the devices placed on the three phases of a transmission line to verify the feasibility of applying IoT techniques to high voltage transmission systems. The results show that this proposed sag monitoring system has overcome the challenge brought by the strong electromagnetic field surrounding a transmission line with high voltage. By adopting IoT techniques, the proposed system is able to be widely implemented on large-scale power grid systems.

Power failure resulting from tower collapse due to violent seismic events might bring enormous and inestimable losses. The Chi-Chi earthquake, for example, strongly struck Taiwan and caused huge damage to the power system on September 21, 1999. Nearly 10% of extra high voltage (EHV) transmission towers were damaged in the earthquake. Therefore, seismic hazards of EHV transmission towers should be monitored and evaluated. The ultimate goal of this study is to establish a damage level assessment model for EHV transmission towers. The data of earthquakes provided by Taiwan Central Weather Bureau serve as a reference and then lay the foundation for earthquake simulations and analyses afterward. Some parameters related to the damage level of each point of an EHV tower are simulated and analyzed by the data from monitoring stations once an earthquake occurs. Through the Fourier transform, the seismic wave is then analyzed and transformed into different wave frequencies, and the data would be shown through a response spectrum. With this method, the seismic frequency which damages EHV towers the most is clearly identified. An estimation model is built to determine the damage level caused by a future seismic event. Finally, instead of relying on visual observation done by inspectors, the proposed model can provide a power company with the damage information of a transmission tower. Using the model, manpower required by visual observation can be reduced, and the accuracy of the damage level estimation can be substantially improved. Such a model is greatly useful for health and construction monitoring because of the advantages of long-term evaluation of structural characteristics and long-term damage detection., {"references":["CH Loh, CY Huang, KL Wen, ML Lin, CP Hsiao, KC Chang, BJ Shih, MH Hsu, CC Lin, HK Wang, WY Chien, JF Chai, TJ Teng, CH Yeh, CS Huang, GY Liu, WH Teng, SY Chang, YK Yeh, MJ Lai, SH Wang, LL Chung, WI Liao, ZK Lee, CC Hsu. \"Streamline Report of the Comprehensive Disaster Investigation on Chi-Chi Earthquake\" National Center for Research on Earthquake Engineering (1999) (in Chinese).","JY Hsu, CH Chen, SW Tseng, HY Ho, SW Sun, CA Wei, JS Jwo. \"An Analysis of the Safety Strategy of Power System in Taiwan from the Power Outage from \"729\" to \"921\".\" Research, Development and Evaluation Commission, Executive Yuan (2000) (in Chinese).","GY Liu, YJ Wang, CW Liu. \"Study on the Risk Analysis and Disaster Reduction Strategy of Power System\" National Center for Research on Earthquake Engineering (2008).","HN Li, WL Shi, GX Wang, LG Jia. \"Simplified models and experimental verification for coupled transmission tower–line system to seismic excitations.\" Journal of Sound and Vibration 286.3 (2005): 569-585.","T Yin, HF Lam, HM Chow, HP Zhu. \"Dynamic reduction-based structural damage detection of transmission tower utilizing ambient vibration data.\" Engineering Structures 31.9 (2009).","T Li, L Hongnan, L Guohuan. \"Seismic response of power transmission tower-line system under multi-component multi-support excitations.\" Journal of earthquake and tsunami 6.04 (2012): 1250025.","M. C¸elebi, A. Sanli, M. Sinclair, S. Gallant, and D. Radulescu \"Real-time seismic monitoring needs of a building owner—and the solution: a cooperative effort.\" Earthquake Spectra 20.2 (2004): 333-346.","A Kangi. \"Application of Warning and Rapid Estimation of Earthquake Damage (WARED) system in unprepared cities case study: Mashhad, north east of Iran.\" International journal of disaster risk reduction 13 (2015): 139-144.","M. Erdik, K. S-es-etyan, M.B. Demircioglu, U. Hancılar, C. Zulfikar. \"Rapid earthquake loss assessment after damaging earthquakes.\" Soil Dynamics and Earthquake Engineering 31.2 (2011): 247-266.\n[10]\tDepartment of Power Supply. \"Review and Summary of the Damage of Foundation of EHV Transmission Towers in Chi-Chi earthquake, 1999.\" Taiwan Power Company (2000) (in Chinese).\n[11]\tLA Montejo, AL Vidot-Vega. \"An Empirical Relationship between Fourier and Response Spectra Using Spectrum-Compatible Times Series.\" Earthquake Spectra 33.1 (2017): 179-199.\n[12]\tComputers and Structures, Inc. \"Detailed derivation of analytical equations used for response spectrum generation\" (2009)."]}

The objective of this study was to examine the effects of (-)-epigallocatechin-3-gallate (EGCG) on cyclooxygenase 2 (COX-2), prostaglandin E(2) (PGE(2)), and interleukin 8 (IL-8) expression induced by IL-1beta in human synovial fibroblasts. Cells were enzymatically isolated from synovial tissue taken from patients undergoing joint replacement surgery for osteoarthritis. Reverse transcriptase-polymerase chain reaction, immunocytochemistry, and western blotting were used to assess the COX-2 gene and protein expression with the associated mechanisms. PGE(2) and IL-8 secretion into the culture medium was assayed by enzyme-linked immunosorbent assay. COX-2 upregulation in synovial fibroblasts induced by IL-1beta was significantly suppressed by EGCG in a dose-dependent manner. PGE(2) and IL-8 secretion was also induced by IL-1beta stimulation and significantly suppressed by EGCG. The mechanism was associated with the phosphorylation of IKKbeta. EGCG may inhibit the expression of inflammatory mediators, such as COX-2, PGE(2), and IL-8, induced by IL-1beta in human synovial fibroblasts. EGCG may be of value in the treatment of synovial inflammation.

A smart grid is a modernized power grid. Many novel technologies have been used to smart grids. One of the technologies is the wireless sensor network. In this study, a novel backbone communication network is proposed, which combines two different wireless technologies (the ZigBee and Wi-Fi protocol), to form a communication network between the transmission towers in a power grid. The gateway in the network consists of an embedded system and an AP with long-range communication capability. The embedded system is used as a computing platform to deal with sensor readings transmitted through the ZigBee protocol and routing data transmitted between towers via long-range Wi-Fi. Finally, the gateways relay the readings to a back-end server in a monitoring center (e.g. substation, ADCC, and CDCC) through the backbone communication network. Furthermore, to manage all the gateways, a routing algorithm for the backbone communication network is designed to ensure the reliability of data transmission in this study. Simulation is done to test the effectiveness and reliability of the routing algorithm. Although other papers have shown architectures and algorithms for smart grid, they are not proper for power grid in Taiwan due to the distribution of transmission lines. This study proposes an embedded system-based backbone communication network for power grid in Taiwan.

Among natural disasters, earthquakes are a major factor that damages transmission lines and power towers, but the impacts of earthquakes on transmission towers are less discussed. For many countries, earthquakes often cause power outages. Traditionally, the safety of extra-high voltage (EHV) transmission systems is inspected by the staff of power companies. Due to high labor costs and time consuming patrols, system anomalies are difficult to be identified immediately. Therefore, this study develops a seismic assessment algorithm for electrical grid safety monitoring with the wireless sensing technology to assess seismic hazard for the EHV transmission system. In the monitoring system, the environment sensing data can be transmitted in real-time by a wireless network. And the intensity data can be analyzed by the algorithm immediately after an earthquake occurs. Specifically, peak ground acceleration (PGA) is adopted as the seismic intensity parameter, and effective peak acceleration (EPA) is a reference parameter used to evaluate towers seismic hazard. Based on the simulation and verification results, the accuracy of the proposed seismic intensity algorithm is high, and the calculation speed is fast. Thus, the purpose of early warning can be achieved by using the proposed algorithm.