Recovery Voltage Of Circuit Breaker Research Articles

Analysis of Transient Recovery Voltage of 500 kV Line Considering Current Limiting Reactor

To limit the short-circuit current level, the method of series current, the limiting reactor is used to limit the short-circuit current, and the common access mode of the current limiting reactor is direct access. The series current limiting reactor can effectively limit the short-circuit current in 500kV power system, but after it is connected to the system, it will increase the transient recovery voltage steepness in case of a circuit breaker breaking fault and affect the normal breaking of the circuit breaker. Based on a 500 kV current limiter project, the influence of a lower limit current reactor on the recovery voltage of circuit breaker under different fault conditions is studied by using electromagnetic transient simulation software EMTP. The results show that the transient recovery voltage of the circuit breaker will exceed the standard value after the reactor is connected. When capacitors above 600nF are connected in parallel to the current limiting reactor, the transient recovery voltage could be limited to the standard range.

The Kilometric Faults: Modeling and Normalized Relations for Line Transients and the Breaker-Recovery Voltage

This paper presents a model for analyzing the phenomenon of kilometric faults on power lines. Closed-form expressions for the current and voltage transients along the line, as well as for the circuit breaker-recovery voltage will be derived. The distributed-parameter model results also in an expression for the rate of rise of the recovery voltage transient. The effect of the damping introduced by breaker-resistive switching is also demonstrated.

Theoretical and Experimental Investigations on Circuit Breaker Transient Recovery Voltages

The purpose of this paper is to present the results of theoretical and experimental investigations conducted on the kilometric faults inpower networks and their impact on the electromagnetic transient recovery voltages in the circuit breaker (CB). In the analytical study, an accurate Laplace s-domain distributed parameter analysis used to obtain A,B,C and D constants of two transmission systems before and after CB. Having the input impedances of two line sections derived from network constants and the laplace transform of the interrupted fault current, simulated by injection of a current ramp time function, an s-domain expression for voltage across C.B. is obtained and laplace-inverted using a numerical technique to obtain its corresponding time waveform. In an expeimental study, a Transient Network Analyzer (TNA) was used for simulating two line sections and Current Injection Unit (CIU). Circuit breaker recovery voltage could then be observed and photographed using a cathode ray oscilloscope and a suitable camera. Different fault and breaker locations could be simulated on TNA by changing the place of the CIU. A comparison showing the agreement between analytical and experimental studies will be presented and several case studies will be reported.

High Phase Order Transmission--A Feasibility Analysis Part II--Overvoltages and Insulation Requirements

High phase order transmission (HPO), the use of more than the conventional three phases, is a unique approach to more efficiently using the overhead transmission rights-of-way. This paper evaluates those areas which impact phase clearances and insulation requirements. Fault overvoltages, overvoltagees due to interphase coupling, switching surges, rate of rise of circuit breaker recovery voltage, and lightning performance are analyzed. Additionally, the effects of wind, ice, fault currents, and phase spacer performance on conductor spacing are considered. Representative conductor spacings and terminal insulation levels are tabulated based on the foregoing analyses.