low power with ME1115 engine and SEVOCN GEN4 Size 4

[girts.romanovskis]

Hello colleagues,
I am currently working on an electric tractor.
I don't have much experience with SEVOCN.
Everything is fine with the running engine. So I won't write about it.
I have a problem with the hydraulic pump motor:
The systems consist of a SEVOCN GEN Size 4 controller, a motor ME1115 and a battery system 105V. I think I have successfully installed the engine off set degrees.
The engine should run at 2400 rpm.
I have problems with the engine running optimally.
The desired engine power is not being reached because the controller does some kind of power limiting.
I do not understand what is causing it. the maximum current to the motor is 95A and the maximum force is 28Nm, but it is at a time when the motors have almost stopped, at low speed.
When the speed drops to 1400 the maximum force is about 17Nm.
It seems weird that with the engine stopped, the "Voltage limit circle magnitude A" parameter is at a maximum of 32k.
Can someone send me DCF file for engine ME1115 or suggest what is wrong with my engine parameters?
I'm adding some pictures.

 

[j bjork]

There are some sevcon threds on the forum that might have some interesting information.
Here is probably the biggest: https://endless-sphere.com/forums/viewtopic.php?f=10&t=36146

I have struggled a little in my yamaha thread too, not sure if that is something of use to you.

Some other threads:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=109180
https://endless-sphere.com/forums/viewtopic.php?f=30&t=94143
https://endless-sphere.com/forums/viewtopic.php?f=10&t=88647
https://endless-sphere.com/forums/viewtopic.php?f=30&t=88205
https://endless-sphere.com/forums/viewtopic.php?f=38&t=88679
https://endless-sphere.com/forums/viewtopic.php?f=38&t=88473

 

[girts.romanovskis]

Hello J bjork,
thanks for the info.
I have reviewed most of these topics.
Unfortunately, my problem is that I am not sure about the configuration that was pre-installed on the controller.
I have played with those parameters whose significance I understand. However, as the forum writes, SEVCON has a "user-friendly" interface.
I decided to write an email to John from Motenergy. I hope that he will send me tested engine parameters.

 

[girts.romanovskis]

After contacting John, I received the necessary engine data from him.
The engine now develops the required power without much effort.
I think the Seller had entered the parameters of another engine in the controller.
In any case, they did not match the set data.
Thanks J Bjork for the support! The topic is closed.

 

[j bjork]

Very good that you got it solved, what parameters was the problem?

It is very interesting to me, as I am in partly the same place trying to get as much power out of my motor with a sevcon as possible.
Not the same motor, but trying to figure out what settings are relevant for what.

 

[girts.romanovskis]

Unfortunately, I think I can help.
My case is specific. I bought the motor and preconfigured controller from a Latvian electric kart manufacturer.
After asking them to send me the engine parameters again, because I suspected that the Engine parameters are incorrect, I received an answer that they will not send them to me, because I have used the software and may have made changes to the configuration myself, and therefore it is no longer their responsibility.
The controller was not fully configured and of course I needed to complete the configuration with input configuration and throttle adjustment, as well as switching from torque mode to speed mode.
I was extremely surprised by this position.
Usually, all electrical machine builders are like a friendly community.
Nor do I understand what exactly was behind such a formal position. My guess is that they sold me an engine that they had not used and were not going to use. Some configuration from another type of motor was placed in the controller.
Unfortunately, there are also such sellers.
But despite that, I received help from John.
After receiving the information, I found that none of the engine parameters (Minmum manetizing Current, stator inductance, voltage Constant (Ke), (Kp), (Ki)) were correct, except for the number of poles .
By entering the following parameters and tuning the "Speed proportional gain” and “speed integral gain” parameters, I got an appropriate result.
I did not need to reach the maximum power of the motor because I use the motor as a hydraulic pump motor, but the difference was huge.
I conclude that in my case the action of the Controller was an obvious occurrence of the calculated limits, which led to a power limitation. As these parameters did not correspond to the real engine, these calculated limits were different than they should be.

I recommend that you make sure that you use the correct engine parameters specified by the manufacturer.
In some cases, people change these parameters to get the engine running for their own needs.
For example, to use less batteries.