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Redundant power supply
'
Redundancy in
engineering' is the duplication of critical s of a system with the intention of increasing reliability of the
system, usually in the case of a backup or
fail-safe.
In many
safety-critical systems, such as
fly-by-wire aircraft, some parts of the control system may be triplicated. An error in one component may then be out-voted by the other two. In a triply redundant system, the system has three sub components, all three of which must fail before the system fails. Since each one rarely fails, and the sub components are expected to fail independently, the probability of all three failing is calculated to be extremely small. Redundancy may also be known by the terms "'Majority voting systems'" or "'voting logic'".
Forms of Redundancy
There are four major forms of redundancy, these are:
★ Hardware redundancy, such as
TMR
★ Information redundancy, such as
Error detection and correction methods
★ Time redundancy, including transient fault detection methods such as 'Alternate Logic'
★ Software redundancy such as
N-version programming
See also
★
Common mode failure
★
Data redundancy
★
Double switching
★
Fault tolerant design
★
Radiation hardening
★
Reliability engineering
★
Reliability theory of aging and longevity
★
Safety engineering
★
Self-healing ring
★
MTBF
References
#
Redundancy Management Technique for Space Shuttle Computers (PDF), IBM Research
#
Majority voting systems
#
Designing Integrated Circuits to Withstand Space Radiation
#
Using powerline as a redundant communication channel
External links
★
Secure Propulsion using Advanced Redundant Control