Siemens 6MD85, Manual

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(d) Actual voltage outside the bandwidth after T1, switching procedure initiated
(e) Switching procedure concluded, actual voltage within the bandwidth
Linear, Inverse
With linear control response, the voltage controller reacts independently of the control deviation after the set
time
T1 delay
. If more than one tap-position change is required to bring the actual voltage back within the
bandwidth, the set time
T2 delay
takes effect.
With inverse control response, the time
T1 delay
depends on the magnitude of the control deviation. Small
deviations are tolerated for longer than larger ones. If the time delay is very small in accordance with the set
characteristic curve, the time
T1 Inverse Min
takes effect.
The set inverse characteristic curve is a function of the parameter
T1 delay
. The characteristic curves arising
for different settings of the time
T1 delay
are shown in chapter 6.9.4.1 General , margin title Parameter:
T1
characteristic
.
Zero Potential or Voltage Recovery
If the actual voltage is not within the defined bandwidth after a voltage recovery, it can be necessary for the
voltage controller to send the 1st adjusting command with the T2 time. For this purpose, the parameter
Regulate with T2 at start
must be activated.
[dw_istgro-130215, 1, en_US]
Figure 6-125 Actual-Voltage Curve during Control with T2
(1) Actual voltage below the minimum voltage
(2) After switching on, the change to a higher tap occurs with time T2
(3) After the voltage recovery, the actual voltage is above the bandwidth
(4) Actual voltage outside the bandwidth. A fast step down mode is carried out with the time T2 until
the bandwidth is reached.
Control Functions
6.9 Voltage Controller
460 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017