Design and Development of Outdoor Vacuum Circuit Breaker using Spring Charged Operating Mechanism

Abstract

The requirement of electrical power without interruption is going to be more and more important considering the present growth of industrialization and per capita energy consumption. To meet this requirement, the need on reliability of each individual component is growing. For a power supply system, the circuit breaker constitutes the last link in the chain of the protection equipment. Circuit breaker provides automatic protection in response to abnormal load conditions, in power transmission or distribution network. The circuit breaker may therefore be called upon to perform lots of various operations such as interruption of terminal faults, interruption of small inductive currents, interruption of capacitive currents, no-load switching or out-of- phase switching. The objective of the dissertation is to design and develop a outdoor vacuum circuit breaker (VCB) with a spring charged operating mechanism to achieve the desired performance effectively. This VCB, Porcelain Clad Outdoor Breaker (PCOB), works at a rating of, 12 kV, 2000 A and 26.3 kA. The operating mechanism is to be designed to obtain desired parameters for performance like contact travel, closing & opening speed, bounce, override, bounce, etc. have to be obtained. This project work includes design and analysis of kinematic linkages, auxiliary switch linkages, cabinet, support structure, energy balancing, dynamic analysis, torque balancing, center of gravity calculation, etc. Various kinematic, force and torque analysis are accompanied with the design of VCB components. Also, seismic analysis of PCOB has been performed to ensure operational behavior of CB during seismic activity.