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18
ALARMS
Alarms are event signals which the regulator does not operate.
MAXIMUM FIRING ANGLE
➢
Alarm reference: 100% firing angle of the thyristors.
➢
Time for alarm action: 1 second.
➢
Signaling: Alarm Led constantly lit in
Yellow-Green
.
MICROCONTROLLER FAILURE
➢
Alarm reference: Perda no sinal de clock interno
– watchdog atuando.
➢
Time for alarm action: instantaneous.
➢
Signaling: Alarm Led constantly lit in
Shock Pink
.
VIRTUAL SWITCH
The virtual switch (digital switch) is represented by the figure block bellow:
Its activation is made internally by the over voltage, excitation overcurrent, generator overcurrent
protections.
PARALLEL OPERATION WITH REACTIVE COMPENSATION
When the generator is operating synchronously to a network or other generator, it is said to be
operating in Parallel.
In this mode of operation, the regulator can no longer keep the output voltage of the regulator fixed,
since the generator is now connected to other generators and all will have the same output voltage.
In this case, it is necessary to introduce an additional control, "Droop" mode to modify the reference
voltage of the generator according to the variations that occur in the reactive power of the generator.
The Droop mode reads the reactants and compensates in the feedback to keep the voltage of the
generator close to that of the bar, thus reducing the reactive generator.
This compensation is limited by the droop trimpot that determines the maximum allowable
variation in the reference to maintain the reactive.
Figure 14
–
Virtual switch
