Enova motor parameter setup

[Peter]

Hello Forum.
My first post here so a quick intro....
I am using the Enova 3ph 90Kw motor coupled to the Enova power stage with the Damien/Johannes Combi V8 board and Johannes Olimex board running v4.87 software.
My questions to the forum please ...
The motor rating plate gives two values for RPM, Continuous 3600rpm and Max 9000rpm. Also two values for Frequency, Base 121Hz and Max 305Hz, however I am trying to work out what settings to use for the following...
Fweak
Fslipmin
Fslipmax
Not sure what to set the parameters to ?
I wish to use the full rpm range, max 9000rpm, motor rated voltage 208v.
DC bus voltage at present is 230v most probably will be increased to 280v later once I am rolling.
If anyone is based in the North West UK please say 'hello' too Maybe a chance to meet and greet fellow DIY enthusiasts.
All the best. Peter

[johu]

So 208V AC will require about 300V DC. So make sure you have calibrated DC bus voltage measurement and then set udcnom=300. Set fweak=120 and fmax=305. fslipmin=121-(3600/30) = 1, fslipmax you can start with 3 and later raise to 5.
Since you are using udcnom, the actual fweak and boost values will be calculated from the actual bus voltage. You can see the calculated values in boostcalc and fweakcalc.

[Peter]

Thank you Johannes. I will try the suggested settings and report back.

[Peter]

Hi Johannes. Please could you answer a quick question or two...
When udcnom is set do the values for boost and fweak change depending on rpm and current or are they fixed at all times by udcnom value ?
Does iacmax influence shut down or limit throttle when its value is exceeded ?

[johu]

Yes the point of udcnom is to automatically determine the values for fweak and boost should the voltage be unequal to udcnom. You can see the result of the calculation in boostcalc and fweakcalc.
iacmax the topic of the week iacmax tries to preempt over current shutdown by reducing slip and output voltage as it is approached. "Approached" in this case means it starts throttling back when the peak current on any phase exceeds 80% of iacmax. That way I want to make sure that iacmax is never exceeded.

[Peter]

Hello Johannes. Thank you for your reply. Watched Damiens video just now, so iacmax was the culprit. Interesting how it affects the inverters working. With respect to your mention of limiting code, what are the effects of idcmin and idcmax, do they also do similar ? I guess eventually we build up a detailed knowledge base of all parameters and how they affect each other. Should we therefore have an area on the forum where we can reference these facts ? Thank you once again. Peter

[damian.lo]

Hello all,

Exactly I was thinking about the same, but You wrote it like directly from my mind
All of the time I'm wondering how one parameter affects other and how to set all up to motor plate. Now I'm doing like blind man little left-little right and see if is better or worse - maybe if Johannes or other "big brain" will have little more time will explain something more.

[arber333]

Yes the point of udcnom is to automatically determine the values for fweak and boost should the voltage be unequal to udcnom. You can see the result of the calculation in boostcalc and fweakcalc.
iacmax the topic of the week iacmax tries to preempt over current shutdown by reducing slip and output voltage as it is approached. "Approached" in this case means it starts throttling back when the peak current on any phase exceeds 80% of iacmax. That way I want to make sure that iacmax is never exceeded.

When i set up the iacmax for my motor i had to account for quite some error. It was almost 1/3 value. So i set my Imax value at 220A and went for a drive. I amost had a fit since i could get over 280A easily! My poor Kokam have self destruct quite near that value. Then i started to reduce Imax. For my system i used Imax 160A so i could get a repeatable torque reduction at 230A battery amps. It works great now however hard i press the pedal.
Motor amps reduction worked good from the start. Heh, its funny the sound of motor amps reduction active sounds almost like holding a cat by the tail .