DMOC645 with GEVCU 4.2, DC currents never gets over 150A during the test described.What controller are you using and how many amps.
I am using a Siemens 1PV5135-WS14 together with a Nissan Leaf pack. I'm not sure this combination is going to work out as I'd hoped.
The nominal voltage of the Leaf pack is 360V, but up to 400V fully charged. The name plate on the motor says the motor is wound for 215VDC. I am testing the car at the moment with the voltage at 385V. I have my torque limited to 300 Nm and a coolant flow rate of about approximately 10-20 lpm (with a Pierburg CWA50 pump).
When I accelerate (maybe 60% full throttle) on a moderate hill climb (maybe 5% grade) the motor temperature goes from 28 deg C to deg 80 C in a couple of seconds. As soon as I stop accelerating is cools down at about the same rate to 28 degC again. I have been thinking maybe I have an airlock somewhere in the cooling system, but last evening I started thinking may the issue is more fundamental.
The voltage is much higher than the nameplate suggests at 360V nominal. Is it possible that the motor is approaching magnetic saturation? Is the overvoltage causing substantial core losses leading to the overheating issue? Has anyone else used one of these motors at a similar voltage?
Any input would be much appreciated.
From the attched, taken from a Semiens motor operating instrction document, it does not matter. "select as required" that is best for your installation.Great thanks for that info,
I'm going to get GEVCU to report the stator temperature only, that should tell me definitively if I have a cooling problem or an algorithm problem. I think it would be plausible that the rotor temperature could rise that quickly. With 360VDC and 350A the input power is around 122KW. Assuming 85% efficiency, the power dissipated inside the motor is > 10KW. If cooling is inadequate things will get hot fast.
Does the direction of coolant flow matter in these motors. I didn't see any indication like "INLET" and "OUTLET" on the motor.
I was having the same issue with my Ford Ranger PV5133 and DMOC645 combination. The DMOC was supplied with a configuration for a different siemens motor, which likely had a different rotor resistance. Ideally updating the DMOC resistance to the correct valve would be the way to go but this information has proven difficult to obtain. For now I have increased the allowable rotor temperature until the continuous rated horsepower could be achieved as well as about 6 seconds of the sprint rated power.OK, here is what I have learned through my investigations into my acceleration issue. The temperature you are seeing clime rapidly is the rotor temperature.There is no physical rotor temperature sensor. Rotor temperature is a derived (calculated) based on calculated Iq rotor current. The rotor temperature limit is set at 200C.In my case the calculated temperature reaches the limit when I quickly accelerate the Mini.The calculated rotor current rapidly ramps (3 sec) to around 371A, rotor temperature reaches 200C and limits kick in and the rotor current/available torque rapidly drop ending the thrill of EV acceleration.
There is a time constant parameters associated with the calculated temperature which I have played with, where I have extended the acceleration times. I fear, however, I may be hurting the motor.I thought the Azure software time constant was not correct or the algorithm is not proper.This feature appears to be something that got added in later software release. Maybe to solve some field failure issues. Wonder if any of the other drives (Scott) being used calculate the rotor temperature. It was hard for me to imagine the Rotor temperature climbing from basically room temperature to 200 C in such a short time even at 371A.I found a few induction motor references that indicate it might, and that has made me concerned about it. Perhaps some others here like Major could comment.
So in your case seeing the indicated temperature ramping to 80 C for short intervals is not likely an issue. If you hit the 200C limit you will notice a significant pull back. I would base any concerns on what the physically measured temperatures (Stator) says for any concerns about the actual motor cooling system.The Rotor temperature algorithm uses the measured Stator temperature as the base temperature for its calculation, because the Rotor Temperature matches it, except during Iq current transients.
