Functions; Switching Sequences From The Perspective Of The System Operator - Siemens SINAMICS MV Function Manual

Description

3.3 Functions

Standard monitoring mechanisms
Note
Note for system integrators
These standard monitoring mechanisms are implemented in the converter. Within the scope of
a system acceptance test, check and document the correct principle of operation in combination
with external components.
• a)
After a firing pulse inhibit, the Control Unit activates the thyristor monitoring functions on
the PSAs via DRIVE-CLiQ communication. By evaluating the gate-cathode voltages, the
thyristor monitoring detects thyristors in the power unit that are in the conducting state (not
turned off). Conducting thyristors (not turned off) cause the line-side circuit breaker to be
immediately opened. The SIMOTION-CPU directly opens the circuit breaker via a digital
output of a TM15 module, which is physically coupled to the CU320-2 via a DRIVE-CLiQ
connection.
• b)
In addition, the current actual values that are received from the PSAs via the DRIVE-CLiQ
connection are monitored in the Control Unit. After a firing pulse inhibit, if the current actual
value of a converter is not equal to zero, then the Control Unit opens the line-side circuit
breaker via a digital output of the TM15.
• If a DRIVE-CLiQ communication error occurs between the Control Unit and the PSAs, then it
is possible that the monitoring mechanisms under Point a) and b) no longer function reliably.
This is the reason that immediately after a DRIVE-CLiQ fault/error is detected, the circuit
breaker is tripped by the PSAs.
3.3 Functions
3.3.1

Switching sequences from the perspective of the system operator

For system operation that uses the "Two-channel firing pulse inhibit" function, it makes sense to
maintain a sequence for deactivating and activating the firing pulse inhibit. This also applies
when switching on the drive again.
12
Two-channel firing pulse inhibit
Function Manual, 07/2021, A5E51227986A