Kollmorgen AKD PDMM series, User Manual

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AKD PDMM User Guide | 7.3.2 Calculations
IL.OFFSET IL.FOLDFTHRESHU VL.THRESH MOTOR.ICONT
IL.INTEN IL.FOLDWTHRESH VL.KVFF MOTOR.PITCH
IL.IVFB IL.MFOLDD PL.KP MOTOR.POLES
IL.KPDRATIO IL.MFOLDT PL.KD = 0 (Default
Value) MOTOR.TYPE
7.3.2 Calculations
KAS IDE uses the following equations to calculate parameter values.
Current Loop
The current loop proportional gain (IL.KP) must be such that the current loop closed loop crossover
frequency/bandwidth (BW) nominal is the lesser of 2000 Hz or (PWM Frequency/4).
Then, with this frequency:
IL.KP = 2*π*(desired bandwidth in Hz)*(motor L line-line in H)
Setting the D and Q components
Velocity Loop
VL.KP = (2*π*75)*(2*Jm/Kt) = 300*PI*Jm/Kt
VL.KI = 5
Slider Tuning
The slider tuning algorithm in KAS IDE currently uses the following algorithm.
Input - Motor Data
The values for inertia, Jm (Kg / cm2), and torque constant, Kt (Nm/A), are obtained from either the SFD or
the motor model number that you select.
Constants
Velocity Loop Bandwidth – BW = The default value is 75Hz.
Input - Inertia Ratio – Q = The default is 1.
Output - Control Loop Gains
VL.KP = 2 * π * BW * Jm * (1+Q) * 0.0001/Kt
VL.KPI = BW*0.08 -1 (minimum of 1)
PL.KP = BW/5
7.4 Foldback
The foldback feature in the AKD PDMM protects both the motor and the drive from overheating. Two cur-
rent foldback algorithms run in parallel in the drive: the drive foldback algorithm and the motor foldback
algorithm. Each algorithm uses different sets of parameters. Each algorithm has its own foldback current
limit, IL.DIFOLD (drive foldback) and IL.MIFOLD (motor foldback). The overall foldback current limit is the
minimum of the two at any given moment.
IL.IFOLD = min (IL.DIFOLD, IL.MIFOLD).
Kollmorgen™ | December 2012 47