Lenze E94AxPExxxx - Manual (Page 192)

6 Motor interface
6.4 Servo control (SC)
192
Lenze · 9400 Servo PLC· Reference manual · DMS 4.0 EN · 11/2013 · TD05/06
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6.4.1.1 Optimise current controller
An optimisation of the current controller is useful, as the two controller parameters gain ( C00075 )
and reset time ( C00076 ) depend on the maximum current required and the switching frequency set.
For this purpose, the controller parameters only need to be adapted once at a fixed switching
frequency.
We recommend to select a switching frequency
• as low as possible if the controller is to be operated frequently at the maximum current limit.
• of 8 kHz (up to and including model 7) or 4 kHz (from model 8 onwards) if the maximum current
limit will not be reached or will only be reached rarely.
The controller parameters are then automatically adapted to the other switching frequencies.
In a test mode you can select current setpoint step-changes and optimise the setting of both control
parameters by evaluating the step responses.
• The starting values for gain and reset time can be calculated with the following formula:

Note!
The current controller should always be optimised if a motor of a third-party
manufacturer with unknown motor data is used!
Gain
Stator leakage inductance
340 μs
------------------------------------------------------------------- =
Reset time
Stator leakage inductance
Stator resistance
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