علي اراني زاده

Increasing preventive maintenance (PM) using circuit breaker (CB) condition monitoring can reduce maintenance costs if sufficient information is provided about the condition of this expensive equipment. Condition monitoring of the CBs takes into account the functional age (not the natural age) of the CB. This functional age depends on the wear-out of the CB. In this thesis, by using the current data of the CB coil current recorded of the CBs in the power system network, an algorithm has been developed for the comprehensive assessment of the CB condition. Based on this, at first, using the self-eva‎luation decision-making algorithm (SEDMA), the maintenance priority between the CBs of a network is obtained. This algorithm works in such a way that the performance of the CB is eva‎luated in comparison with other CBs, as well as the performance of the CB with itself and over time. This issue will lead to first measuring the condition of the CB by itself, and if the condition of the CB deteriorates over time, the CB will be prioritized for maintenance. Secondly, the CB is compared offline with other CBs, and due to the failure of the CB compared to other CBs, the priority of equipment maintenance is finalized. Then, using sensitivity analysis, it is determined whether the CB with the highest priority needs maintenance or not, and in other words, the degree of failure of each CB is determined. In the continuation of the work, the CBs are prioritized using the failure probability density function and the cumulative failure probability function. Then, by introducing the reference CBs and comparing them with the CB with the highest priority, it is determined whether this CB needs maintenance or not. Finally, by creating two sets of reference CBs and using time characteristics and/or reference mechanisms and comparing them with the CB characteristics and/or mechanisms with the highest priority, the damaged part of the desired CB will be determined. The proposed method of this treatise is flexible and completely based on defined rules and relies only on recorded data, and the results are clear and reliable. This proposed method is flexible because by changing the type of input data to equip the CB, this procedure will still answer the problem. The case study in this thesis is related to two similar CBs. Also, the improvement of the condition of the CB will be determined by carrying out maintenance operations.

تعميرونگهداري , كليدقدرت , مديريت دارايي , پايش وضعيت , تصميم سازي , اولويت بندي

maintenance , circuit breaker , asset management , condition monitoring , decision-making , priorotizing

ali aranizadeh

ahmad gholami - seyed mohammad shahrtash