sanfox wrote: ↑
May 13, 2018 1:27 am
This motor can give 20 kW peak with this controller (manufacturer also call it DLC-20). Your test power is 28,9 Hp eqivalent to 21.25 kW. Your can give 26 kW peak with sevcon controller gen 4 size 4 model with nominal 110V if you rise fact voltage up to 150V. About efficiency, I have 3D efficency map of the same type motor with little bigger size. So the top of the hill with max efficency (93%) lies approximately in the point with 40% of top torque and 60% of top rpm.
Can you said more about Buik Lacross motor testing? What controller you have use?
ok, then I shouldn't expect much higher power. My concern was about the point at torque knee starts to decrease, because the more charged the batteries are and the higher the current control constants are the torque lasts to higher RPM and then more power is provided
Can you share the 3D efficiency map?
keep in mind that I consider the efficiency of the whole set: controller + motor + chain (as it it what I expect in the vehicle / kart)
For the Buick Lacrosse induction motor, efficiency is in general lower. For higher torque peaks and low rpm it can be extremely low (30 to 50% range), although as speed increases and torque decreases it reaches good values (80 or 85%), for this reason I think this is a good motor for road (light loads), but not for kart (as you are normally only braking/accelerating almost full torque)
You can see several power and efficieny charts at the Buick Lacrosse post.
The maximum HP I got was 38 HP, but of course applying a high current (550A) and only in DELTA mode (originally WYE/star). 550A in DELTA is equivalent to 321A in WYE (manufacturer recommends maximum 230A)
I used the Curtis 80V 550A model, which was relatively easy to configure.
Also comparison between WYE and DELTA configurations gives much better efficiency and power results in DELTA config (average 10% better).
Slip Gain parameter changes from 16% (WYE) to 8% in DELTA, which I think helps to decrease inducted heat losses in the rotor