Siemens 6MD85, Руководство пользователя

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Figure 6-79 Operating Range Under Synchronous and Asynchronous Conditions for Voltage (V) and
Frequency (f)
Balancing Commands for Voltage and Frequency
The stage has 2 separate blocks, split according to balancing commands for the voltage and the frequency.
The balancing pulses for increasing or decreasing the voltage and the frequency are generated in each block.
The following values affect the pulse width of the balancing command:
•
Current measured values for differential voltage
•
Current measured values for differential frequency
•
Set gradients dV/dt and df/dt
In addition, the minimum pulse duration (
T V pulse min
,
T f pulse min
) and the maximum pulse dura-
tion (
T V pulse max
,
T f pulse max
) are defined. The minimum pulse duration allows for a safe reac-
tion of the controllers while the maximum pulse duration prevents an overreaction, that is an exceedance of
the desired target value. A settable dead time intercepts transient states.
The balancing commands are active once the synchronization function has been started.
Balancing Commands for Voltage
The parameters
Max. voltage diff. V2>V1
and
Max. voltage diff. V2<V1
are used to determine
the voltage range that defines the admissible voltage difference for asynchronous parallel switching. The
middle of the voltage range is defined as the set point value for the balancing commands.
The parameters
T V pulse min
and
T V pulse max
define the minimum and maximum duration of the
balancing pulse.
The parameter
dV per second
defines the speed for the set point value change of the voltage control. The
functionality uses the measured current voltage difference and the setting value of the parameter to deter-
mine the actuating time. The following equation applies:
[fo_voltage-adujsting-command, 1, en_US]
Control Functions
6.4 Synchronization Function
392 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017