04.96 7 Drive Machine Data (SIMODRIVE Drive MD)
7.3.2 Drive MD (data description)
Diagnostic function "Voltage-controlled Vq operation" (up to SW 4)
A voltage-controlled operating mode (V/F mode) is applied in order to diagnose speed or
current sensor faults. In this operating mode, voltages Vq and Vd = 0 as well as a
frequency are input as controlled quantities. As a result of the transformation (d/q
R/S/T), a constantly changing rotating field is applied to the motor via the trigger
equipment ASIC, making it possible to attain a speed within the nrated/5 range in V/F
operation. The system oscillates at higher speeds.
Corresponding machine data are as follows:
Motor frequency V/F mode (MD 1660)
Ratio V/F during V/F mode (MD 1661)
If MD 1661 is set to an excessively high value, the resulting Id current at nrated/5 causes a
temperature rise in the drive and an additional increase in oscillation at high speeds.
If MD 1661 is set to a very low value, the resulting Iq current value is too low, making it
impossible for the drive to follow the specified frequency.
An operating status message is transmitted to the SERVO by means of bit 28 in the status
word.
The current and speed controllers are not active in V/F mode
Unfavourable parameter settings may cause excessively high currents to occur in V/F
mode; the existing current monitoring function therefore remains active.
Signal number min/max memory
1651
Default value Lower input limit Upper input limit Units
0 0 100 –
Active
at once
Input of signal number of memory location to be monitored by the min/max memory function.
Caution:
This machine data is relevant only for Siemens-internal purposes and must not be altered.
© Siemens AG 1992 All Rights Reserved 6FC5197- AA50 7–149
SINUMERIK 840C (IA)