Circuit Breaker Failure Protection Scheme
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MP4 | Video: h264, 1280x720 | Audio: AAC, 44.1 KHz
Language: English | Size: 785 MB | Duration: 1h 58m
How CBF is implemented in Substations, Power Plants & Electrical Systems
What you'll learn
What are different types of breaker failure that can occur in power system
Circuit Breaker Failure due to Mechanism Fail
Circuit Breaker Failure due to non-interruption of fault current
Circuit Breaker Failure due to DC control/trip supply fail
Circuit Breaker Failure due to tripping coil failure
Circuit Breaker Failure due to low DC voltage
Circuit Breaker Failure due to Aux contact failure
Circuit Breaker Failure due to Fire
Circuit Breaker Failure due to delayed tripping
Circuit Breaker Pole Discrepancy
What is Circuit Breaker Pole Discrepancy
Single pole & three pole circuit breaker operated mechanisms
advantages of single pole tripping & reclosing
How single pole reclosing support system
What is meaning of pole discrepancy
How pole discrepancy is detected in system
Pole discrepancy circuit working
Timer circuit in pole discrepancy
Stage 1 & Stage 2 operations of pole discrepancy
Pole discrepancy during closing command & tripping command.
Re-trip and 2nd stage
What is typical time settings for Pole discrepancy
Creation of 3I0 zero sequence current during pole discrepancy condition
How Pole Discrepancy can lead to indiscriminate tripping in the network
Busbar Schemes
Single Bus Single Breaker Scheme, Double bus single breaker scheme, one and half breaker scheme, double bus double breaker scheme, mesh breaker scheme
How to change over load from one bus to another bus without interruption, advantages of different busbar scheme
Circuit Breaker Fail Philosophy
Circuit breaker failure protection using relay coordination at low / MV levels
What to do & protect if one breaker fail
Understand basic concept of breaker failure, if some one understand well can design and understand all CBF protection schemes & logic
CBF protection example in one and half breaker scheme, how to protect system if middle breaker fail
How to protect system if main breaker fail. CBF protection example in double bus double breaker busbar, consider the case of bus coupler & bus sectionalizer.
Circuit Breaker Failure logic block, CBF initiation function, CBF current guard, CBF Low current mode, CBF CB Aux contact input,
CBF timer, CBF stage 1 & Stage 2, CBF for Mechanical Protection not involving current, CBF protection and End fault protection
CBF Re-trip & 2nd stage faulty CB isolation from sources
CBF when Circuit Breaker is faulty
CBF and lockout function, 86 close block relay
Description
The circuit breaker failure protection provides a backup protection in the case, that the local circuit breaker fails to clear a system fault.
In this training we have started from basic concepts, explained circuit breaker symbol and how circuit breaker look like in substation. We have discussed in training how to represent circuit breaker by ANSI code, difference of circuit breaker and line isolator. What are different functions that are performed by circuit breaker, what is arc, how to quench arc, what are media to quench arc, what will happen if arc is not quenched.
