Reliability Analysis of the Control and Automation Systems in Electrical Substations

This work consists in a detailed reliability analysis of the control, automation, and communication equipment in an IEC61850 based digital electrical substation considering four different communication architectures. Three preventive maintenance plans are defined according to Birnbaum’s importance measure in order to evaluate if a more detailed planning proves to be beneficial. The method used to perform the substation’s reliability and availability analysis consists in a Markov-Monte Carlo algorithm. Moreover, a quantitative cost analysis throughout the substation’s life cycle is conducted to conclude about the economic feasibility of each architecture, allowing more objective decisions to be taken when considering the reliability requirements for electric power systems.<br>This paper is an extract from the academic research conducted by the first author as requirement to obtain the Master of Science Degree in Electrical and Computer Engineering at Instituto Superior Técnico, Universidade de Lisboa, under the supervision of Prof. Paulo J. Costa Branco and the co-supervision of Eng. Andrés A. Zúñiga.<br><br>

Reliability Analysis of the Control and Automation Systems in Electrical Substations

This work consists in a detailed reliability analysis of the control, automation, and communication equipment in an IEC61850 based digital electrical substation considering four different communication architectures. Three preventive maintenance plans are defined according to Birnbaum’s importance measure in order to evaluate if a more detailed planning proves to be beneficial. The method used to perform the substation’s reliability and availability analysis consists in a Markov-Monte Carlo algorithm. Moreover, a quantitative cost analysis throughout the substation’s life cycle is conducted to conclude about the economic feasibility of each architecture, allowing more objective decisions to be taken when considering the reliability requirements for electric power systems.<br>This paper is an extract from the academic research conducted by the first author as requirement to obtain the Master of Science Degree in Electrical and Computer Engineering at Instituto Superior Técnico, Universidade de Lisboa, under the supervision of Prof. Paulo J. Costa Branco and the co-supervision of Eng. Andrés A. Zúñiga.<br><br>

Breed availability analysis of local beef cattle in Seram Utara Timur Seti District Maluku Tengah Regency

This study aim were to analyze the potential availability of breeds for beef cattle development in Seram Utara Timur Seti District. The research method used was a desk study and survey method. Desk studies were conducted by utilizing relevant secondary data from various related agencies, as well as relevant research results. Meanwhile, surveys and direct observations in the field were carried out in the Animal Husbandry Production Center (KSP) areas, namely Wailoping, Kobisonta and Waitila Village. The variables observed included population structure and potential availability of beef cattle. The results showed that the proportion of the beef cattle population for the categories of calves, youth and adults was 23.18; 22.18 and 54.64% respectively. The sex ratio of male to female in all age categories is still below the normal ratio of 1 male to 5. Total breed growth (net increase) was 70 tails per year from the total population of beef cattle in Seram Utara Timur Seti District (13,032 tails). The total growth of beef cattle is still less than 1% (around 130 heads) of the total population, so it is necessary to pay attention for the development of the source area for beef cattle breeding in Seram Utara Timur Seti District.

GNSS Signal Availability Analysis in SSV for Geostationary Satellites Utilizing multi-GNSS with First Side Lobe Signal over the Korean Region

This paper verifies the applicability of multiple Global Navigation Satellite Systems (GNSSs) and side lobe signal utilization in Space Service Volume (SSV), especially for Geostationary Earth Orbit (GEO) missions over the Korean region. Unlike the ground or terrestrial systems, various constraints of space exploration in SSV cause a problem when estimating position using GNSS. This is mainly due to the limit of GNSS signal availability where its dominant variables include altitude, side lobe issues, as well as longitude because of different constellations of several GNSS. The numerical simulation shows the effectiveness of additional side lobe signals from multi-GNSS. In addition, the effect of non-MEO satellites’ signals in SSV for different longitudes is presented.