Online Circuit Breaker Monitoring System. (December 2007) Zarko Djekic, B.S., University of Novi Sad, Serbia Chair of Advisory Committee: Dr. Mladen Kezunovic Circuit breakers are used in a power system to break or make current flow through power system apparatus. Reliable operation of circuit breakers is very important to the well-being of the power system. Historically this is achieved by reg...

The electrical substation components are often subject to degradation due to over-voltage or over-current, caused by a short circuit or a lightning. A particular interest is given to the circuit breaker, regarding the importance of its function and its dangerous failure. This component degrades gradually due to the use, and it is also subject to the shock process resulted from the stress of iso...

The computation program of the transient recovery voltages that appears across the terminals of a circuit breaker, after the low inductive current has been interrupted at the disconnecting no load high voltage transformers, using the routines set developed in Matlab is presented. The computation algorithm is based on the peculiarities of operation of the transformer. The computation program has...

During the last years the medium voltage world has seen a strong increase in demand of flexibility, simplicity and automation of the distribution networks. The Smart Grids concepts have changed network’s needs and solutions with innovative design are required to satisfy these new demands. The standard IEC61850 is driving the innovation in the energy distribution devices enabling new functionali...

High voltage circuit breakers are important protection and control equipment for the power grid. The defects faults of breaker seriously affect safety stability system. As key component operating mechanism breaker, opening/closing coils contain a large amount information about status mechanism. In order to investigate cause difference in current waveforms, this paper analyzes factors affecting ...

This paper presents an optimised power semiconductor architecture based on the CIGBT approach to be used in solid-state circuit breaker (SSCB) applications where the conduction losses have to be as low as possiblewithout compromising the forward voltage blocking capability. Indeed, a high overcurrent turn-off and short-circuit withstand capabilities have to be ensured. Starting from a standard ...

VAR support should be supplied as close to the load as possible to minimize transmission losses. For voltage control and for improvement of total power factor in a distribution system the circuit- breaker switched capacitor banks can be used. The problems with this solution are the voltage steps caused by the large sizes of the capacitor banks as well as the transients caused on insertion. Thyr...