Motenergy ME1304 motor with SEVCON size 6 on Dyno

e-vektor

100 W
Joined
Sep 22, 2013
Messages
101
Location
Spain
Hello

I am opening this new topic for the tests I started last week with the ME1304 motor, so it is not mixed with the Buick Lacrosse moto-alternator topic.
In the first tests I was getting only 12 HP and the torque line was not flat, it started very quickly to decrease. But it seems the fault was in the battery (Pb 72V)

Here is one of the first tests on the dyno:
https://www.youtube.com/watch?v=5H20iD-CvtA&feature=youtu.be

Last Friday I changed to the LIPO batteries (24S x 3P x 16Ah x 10C) charged at 92V and the results were totally different, power reached first 22 HP (with a limit for the battery of 300A DC) and 25 HP (for a limit of 450 A DC). Although the battery was not fully charged (maybe about 40%) the important thing is that now torque is FLAT up to about 2200 RPM, and only starts to decrease when the battery voltage starts to drop (it is expected that the peak should happen at higher rpm for a full charged battery). Unfortunatelly I didn't start the voltage, current measurements and efficiency yet, but I will do this week

ME1403_on_LIPO.png


Torque is about 80 N*m for about 500A AC, which I think starts to be high as the manufacturer declares a maximum of 63 N*m and 420A AC
My goal is to measure max power and its efficiency (despite it is low), and efficiency with less power, for instance at the specified 63 N*m
 
A quick update:

Today I got 28.9 HP with battery full charged and motor cold. I think that the controller needs some time to react, so the next power tests should be more of steady type. Or the controller should be adjusted to react faster (FOC coefficients)

ME1403_28.9HP.png


And I started to measure efficiency. This chart shows its value from 1500 RPM at 50A DC (battery), 100A DC and 200 A DC

ME1404_efficiency.png


I also measured efficiency at 500 RPM and 1000 RPM at approx 100A DC and it was 34% !! and 60% respectively

Compared with the Lacrosse motor (induction) the Efficiency of this PM motor is more flat, while in the induction motor it varies more deeply as the speed increases. Induction motors have normally advantage at higher speeds, while PM motors have advantage at higher torque.
 
Hi! Intersting topic! I want to clarify some details.
May be you mean ME1304 motor model? What size of motor controller do you use?
 
sanfox said:
Hi! Intersting topic! I want to clarify some details.
May be you mean ME1304 motor model? What size of motor controller do you use?

Yes 1304, sorry. Sevcon gen 4 size 6 (550-660A)
 
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?
 
sanfox said:
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
 
This is the graf of another disk motor. I think ME1304 must have efficiency graf something like this.
Graf 1.JPG
I think that you control Buick Lacrosse induction motor via sevcon controller. I collect information how to do it.
May be you have some sevcon tech tips?
 
sanfox said:
This is the graf of another disk motor. I think ME1304 must have efficiency graf something like this.
Graf 1.JPG
I think that you control Buick Lacrosse induction motor via sevcon controller. I collect information how to do it.
May be you have some sevcon tech tips?

you will need a resolver to encoder converter, once you have it and you change the topology to DELTA (strongly recommended) you can execute the Sevcon characterization process, and it is almost done (you will need to configure several details for the vehicle operation, throttle, etc)
but most these things are already explained in the Buick Lacrosse thread
 
a little off-topic, but related with the battery power measurement and efficiency:
I added a pluggin in our software to communicate with SEVCON and Curtis (CANopen) and acquire the controller data to be included within the mechanical power test. This eases the task of calculating efficiency, but also allows to see the FOC variables during the power test (Iq, Id, etc)

Despite I know that most of you will not use this software, I write this post to inform about the availability of all technical info in case anyone want to acquire this data in an arduino project, or whatever.
CANopen enquiry + response frames are relatively easy, and IDs, subindexes are also more or less easy to find, but there are other values as the binary to decimal scales that take more time to find.
 
If you crank field weakening to the limits of stability you can find another 10hp of top-end (assuming battery is able to deliver the current needed). EDIT** That +10hp was also when running 28s pack voltage, at your pack voltage maybe only 5hp more topend.
 
by now the ME1304 has been taken apart to tune another motor in the dyno.
EDIT: my 2 goals with the ME1304 are:
1) get the maximum performance at about 100V, I would expect 30-35 HP
2) get a high effciency setup for about 28-30HP for the karting application


offtopic: I developed a CANopen to OBDII adapter with bluetooth (ELM327 protocol) to be used with Torque App or similar (OSD and Telemetry)

Video:
[youtube]A2WRlnKMZ-I[/youtube]

CANopen_adapter.jpg

CANopen_curtis.jpg
 
according to the second picture (ME13004 120V 660A) I should expect about 37 HP at 100V (100.4 battery pack at full charge), which is quite good. By now I am doing tests at 90-92V, but 100V will work too with SEVCON, and I got about 29 HP, so 35-37 does not seem too far

I am waiting my friend #luigidesign ends his motor tuning in the dyno to continue with the ME1304
 
At the second picture with ME1304 you can see graph with 150V battery and sevcon 110V nominal controller. And you can get 30kW(41 hp) from your motor only if you increase voltage. With 120V battery power of your motor never rise up more than 25 kW (34 hp).
 
I am back again to the testing. After my friend luigidesign finished his tests in the dyno he has been adjusting my SEVCON for the ME1304 motor. Efficiency has been improved a lot at low torque areas. It reached about 86% at the brake (after the chain), and I estimated the losses of chain about 6%, so it should be about 92% which is very close to what Motenergy declares (for low power)
The readings were: 9.9 HP and 21 N*m @100A RMS

ME1304_100A.png


After that I did a test at 400 A RMS, but I have to admit that I cannot go much further with this configuration (4S x 2P) as the max discharge current is 320A DC

Here you can see 25 HP at brake (26.5 HP estimated without chain losses), 71 N*m and about 78% Eff (84% without chain) which is pretty good. Note that during tests the voltage drops as low as 84V, so there still is some marging if voltage is kept close to 100V and motor current is increased to 660A (for a few seconds)

ME1304_400A.png


Now the next step is doing a test with new batteries (100C !) to see the actual max value that this setup can give (95V & 660A target)


And Finally, for the 400A RMS test, here is the Bat Voltage, Bat Current, Motor Temp chart: (read directly from SEVCON with IXXAT)

ME1304_CAN.png
 
Yesterday I did several more tests with the 4S x 3P set (max 480 A DC @ 10C), but results were exactly the same. At the beginning I though the SEVCON was limiting the battery current to 285 - 300 A DC, then I increased the limit to 500 A, but no change at all.
As you said in a previous post this motor is rated for approx 20 KW at 100V, so the only way to go further would be increasing the voltage, but by now it is out of the scope of the e-kart project
Next step is installing the motor and choosing the right gear ratio so corners fit in the good efficiency range, and only the finish straight segment uses the part with Field Weakening
 
Update: we continued adjusting the P.I. and F.W. constants and got 37 HP at brake with battery just charged at 100V (approx 40 HP at motor)
I think this is very very close to maximum for this motor at 100V

ME1304_37HP.png
 
Good job! Good power!
Why controller can't hold max power from 3500RPM to 5000RPM?
Can You make test for max power at long time period?
 
sanfox said:
Why controller can't hold max power from 3500RPM to 5000RPM?
Can You make test for max power at long time period?

indeed that makes me think that we could get a slower decay between 2500 and 4000 and this will provide more power (maybe 5 HP more) since the torque decay is SLOWER after 4000 RPM
 
What Iq Headroom Factor do you set? 85% may be more?
Can You show your power limit map?

May be it's help your progect.
I have made some modifications of my motor which has the same case as yours.
I have made holes inside the case.
Holes in the motor.JPG
And set the externall powerfull blower with filter.
View attachment 1
After some time the filter needs to changing to more bigger one, but I don't testet it yet.
 
yes, about 84%. It is likely the modulation index does not reach its maximum at max power value, then it continues increasing but torque decreases first quickly (I guess before F.W.) and then more slowly (I guess during Field Weakining)

Parameters:

ME1304_parameters.png


Map: (it is flat up to 5000 RPM)

ME1304_map.png


big modifications!
does it work better with air cooling?
or do you just prefer air cooling for simplicity?
I've heard that some people does thicker holes for the water cooling


sanfox said:
What Iq Headroom Factor do you set? 85% may be more?
Can You show your power limit map?

May be it's help your progect.
I have made some modifications of my motor which has the same case as yours.
I have made holes inside the case.
Holes in the motor.JPG
And set the externall powerfull blower with filter.
Externall blower.JPG
After some time the filter needs to changing to more bigger one, but I don't testet it yet.
New and old filters.JPG
 
I plan to use combined cooling water plus air. I have calculated heat dissipation and deside that additional air cooling can give for me minimum additional 6 kW of rated power (15 kW+6kW=21 kW minimum or more). Now I have no time tо check it! If you make additional air cooling you can check it at your stand.
I have found intresting thing in your coefficients.
Your motor has stator inductance 69.9 mH and Ke 0.029 so it's differ from my information about ME1304!
With this coefficients official calculated power limit with 100V battery must be about 25 kW and about 32 kW with 120V battery! I think your motor must has another index! Please check mesuaring inductanse of your motor in vehicle interface, it's untresting for me!
Also your power limit is not so because it's more than real limit! :D
Sevcon instruction sais than if you use wrong Ke it may corse damage of controller by over voltage.
 
What coefficients do ME give?
Ke was measured using the DVT tools

sanfox said:
I plan to use combined cooling water plus air. I have calculated heat dissipation and deside that additional air cooling can give for me minimum additional 6 kW of rated power (15 kW+6kW=21 kW minimum or more). Now I have no time tо check it! If you make additional air cooling you can check it at your stand.
I have found intresting thing in your coefficients.
Your motor has stator inductance 69.9 mH and Ke 0.029 so it's differ from my information about ME1304!
With this coefficients official calculated power limit with 100V battery must be about 25 kW and about 32 kW with 120V battery! I think your motor must has another index! Please check mesuaring inductanse of your motor in vehicle interface, it's untresting for me!
Also your power limit is not so because it's more than real limit! :D
Sevcon instruction sais than if you use wrong Ke it may corse damage of controller by over voltage.
 
Motenergy gives Ke=0,021 for ME1304, Ke=0,032 for ME1302, Inductance 66 mH for ME1304, 75 mH for ME1302.
It's data from official motenergy dcf files. :?: :?: :?:
Logic tell to us that with the same magnets ke must be proportional to inductance. My DVT only check inductance of ME1302 and it's matched to 75 mH. If Ke also right, with inductance 66mH of ME1304 Ke must be 0,028.
In the drawings of ME1302 and ME1304 I have found different data Inductance 66 mH for ME1304, and Inductance 140 mH for ME1302.
ME1304 data.JPG
ME1302 data.JPG
Something wrong in this chimistry!
I know only way how to check Ke with oscilloscope.
What version of DVT do You use?
 
Back
Top