Control Techniques Mentor MP User Manual

Menu 5
Parameter
structure
Keypad and
display
Parameter x.00
Parameter
description format
Advanced parameter
descriptions
Serial comms
protocol
Performance
78 Mentor MP Advanced User Guide
www.controltechniques.com Issue Number: 4
When the flux in the motor is reduced below its rated level the level of torque producing current required for a given amount of shaft torque is higher
than the rated level. In speed control the compensation prevents gain reduction at higher speeds. In torque control the compensation maintains the
torque at the correct level for a given torque demand. In some applications using speed control it may be desirable to have a reduction of gain as the
motor flux is reduced to maintain stability. If this is required, Pr 5.28 should be set to one.
See Pr 5.30 for description.
When the motor is operated in the field weakening voltage region, the relationship between field current and the level of flux can be non-linear.
The drive can include the effects of saturation by representing the flux producing current to flux characteristic as a series of three lines as shown
below:
If Pr 5.29 and Pr 5.30 have their default values of 50 and 75, the characteristic becomes one line and there will be a linear relationship between the
drive estimate of flux and the flux producing current. If Pr 5.29 and Pr 5.30 are increased above 50 and 75 the drive estimate of flux can include the
effect of non-linearity. It is unlikely that information will be available to set up these parameters, and so the values are determined during the rotating
autotune test.
5.28 Field weakening compensation disable
Coding
Bit SP FI DETEVMDPNDRANCNVPTUSRWBUPS
111
Default Eur 0, USA 1
Update rate Background read
5.29 Motor saturation breakpoint 1
Coding
BitSP FI DETEVMDPNDRANCNVPTUSRWBUPS
111
Range 0 to 100 % of rated flux
Default 50
Second motor
parameter
Pr 21.25
Update rate Background read
5.30 Motor saturation breakpoint 2
Coding
BitSP FI DETEVMDPNDRANCNVPTUSRWBUPS
111
Range 0 to 100 % of rated flux
Default 75
Second motor
parameter
Pr 21.26
Update rate Background read
Field
current (%)
flux (%)
50 75 100
100%
Pr
5.30
Pr 5.29
Linear characteristic
(i.e. no saturation)

Control Techniques Mentor MP Specifications

General

Brand	Control Techniques
Model	Mentor MP
Category	DC Drives
Language	English