I gave up on building my own controller after setting a few things on fire and having a few EE's scratch their heads at my IGBT's staying on (after being asked to do so)...no matter what.
Which brings me to where I am now. In order to try to get a better understanding of things beyond the books, I purchased a few Curtis 1253 (80V) controllers and the associated software to make my system (electric motorcycle 72V nom) functional enough to finish the battery charger design--just for the challenge, I know I can buy one of them too--and I ran in to some very interesting behavior from the controller.
System worked OK, top speed about 70mph, but the motor ran hot (270F with NCT) re geared, now top speed of 45mph and motor is cooler.
Controller is designed for series wound DC motors: 80V , 350A with 600A peak.
Motor is wired shunt (actually a SepEx motor which, if I understand correctly, is more of a control strategy than a motor type)
Motor measures very close to 1 Ohm on both the field and the armature, close to 0.5 ohm when wired parallel (shunt)
This should give approx 150A max current which is very close to the measured value when operating at 100% duty cycle and max voltage from the controller measured at the motor.
The monitoring software agrees with the empirical data.
The locked rotor torque is very low, which is what was anticipated with the shunt wound setup, but it is so low that I can easily hold it still with my feet.
Here is the interesting (to me) part.
The controller--with no feedback--will not go over 10V at the motor (and the predictable 50A) also confirmed both by meter and software. When the armature is not moving
Changed a few parameters and the entire controller (with same part number) and get the same result.
I am of the opinion that if I could get max voltage, or 100% duty cycle, I would have adequate torque on starts.
I have a series wound motor on the way so I can continue testing, but what gives?
I realize a series wound motor might very well run 500A at 10V, but how does the controller "know" the armature is not moving?
Please educate me.