Arcteq Generator Commander, Instruction Manual

Page: 473 / 561

6.3 Redundancy
6.3.1 Single system
The system is prepared to have one ("Single") or two ("Redundant") controllers. In the single system,
one controller is used to control one power rectifier.
6.3.2 Controller redundancy
A redundant system includes two controllers and multiple power rectifiers. One of the controllers is
active, while the other is on hot standby; upon the failure of the primary controller, an automatic
change-over to the redundant controller immediately takes place and thus there is no interruption in
the operation.
6.3.3 Power rectifier redundancy
The system can have one or more (redundant) power rectifiers. The redundant rectifiers can be in a
"1+1" or a "n–1" configuration.
In the "1+1" redundancy configuration, one rectifier is in operation while the other one on hot standby. If
the operative rectifier fails, there is an automatic change-over to the redundant one and it takes over
the operation.
In the "n–1" redundancy configuration, there are at least three rectifiers in parallel operation at the
same time. If one of them fails, the operations continue in the remaining rectifiers.
6.4 Others
6.4.1 Diagnostics
The field breaker is monitored with regard to the number of operations as well as the accumulated
breaking current.
The excitation system is monitored with regard to the total number of running hours as well as the
accumulated field forcing as "current-seconds" (that is, A × s above the rated current).
6.4.2 Real-time trending
The following signals are available for real-time trending:
• Positive sequence voltage
• Positive sequence current
• Three-phase active power
• Three-phase reactive power
• Frequency
• DC field current
• DC field voltage
• Control signal
• PSS signal
Their update time is 10 ms. Trending is done by a separate PC software tool, and it is primarily intended
for tuning the control loops.
Genera Generattor Commander or Commander
Instruction manual
Version: 2.07
© Arcteq Relays Ltd
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