Sabvoton SVMC072150 controller review, variable regen *PICS*

Hi there!

Could someone please tell me if the controller requires a battery connection to be programmed via USB ?

I installed the driver/software and I'm able to connect to COM19 which is the 485 interface.

The TX transmit light in the software is flashing, but RX is dead so there is no response from the controller.

The above result is without any batteries connected.

I also tried with a 30V PSU but then I read it needs something like 50V absolute minimum.
With 30V there was no feedback at all. No status LEDS, etc. Can this be right?

Regards
 
How does the field weakening work? Can you have a switch turn it on only when you want the higher speeds and be able to ride around in regular mode most of the time?
 
zombiess said:
To program it you will need > 36V powering the controller.
36V... awww so close :)

Thanks a bunch, it works now. I combined my PSU with a 12V battery and was even able to get it spinning.
 
John in CR said:
How does the field weakening work? Can you have a switch turn it on only when you want the higher speeds and be able to ride around in regular mode most of the time?

If you turn it on but never run the motor in a range where it's needed, there is no loss of efficiency.

Field weakening is set to a certain max phase current, 0-100A. If you set it for 100A then it will allow up to an additional 100A past the BEMF point where your motor would normally stop. If you are riding around at 20mph and your motor tops out at 40mph, then field weakening isn't in effect. If you then command 40mph, some field weakening can come into play during accelerating to that point. If you are going 50mph (10mph greater than your 40mph non field weakening limit) then the extra current is being used.
 
zombiess said:
John in CR said:
How does the field weakening work? Can you have a switch turn it on only when you want the higher speeds and be able to ride around in regular mode most of the time?

If you turn it on but never run the motor in a range where it's needed, there is no loss of efficiency.

Field weakening is set to a certain max phase current, 0-100A. If you set it for 100A then it will allow up to an additional 100A past the BEMF point where your motor would normally stop. If you are riding around at 20mph and your motor tops out at 40mph, then field weakening isn't in effect. If you then command 40mph, some field weakening can come into play during accelerating to that point. If you are going 50mph (10mph greater than your 40mph non field weakening limit) then the extra current is being used.

Are you positive about that? A motor "tops out" at different speeds for different throttle duty cycles, so unless field weakening kicks in only at WOT then it could affect efficiency at any speed. eg Let's say you have your 3 speed switch at 50%, so without field weakening the motor would push you to 20mph on the flats, but with that same duty cycle won't field weakening result in a higher speed?

Or am I missing something in how it works? I think I understand how field weakening works in general, but not how it's implemented or exactly when it kicks in.
 
I've never used a speed limiter on this controller with field weakening enabled (there is no need to since you are directly controller power, just like a car or motorcycle throttle) so I don't know for sure. The throttle mid point and mid point current are also individually variable so the control can be tailored to desired "feel"

I've never seen field weakening draw any current (the controller can report this info back to a PC/android device while in operation) when I ride around at part throttle unless I was at high speed where field weakening was required to maintain the required speed (>40mph on my setup).
 
zombiess said:
I've never used a speed limiter on this controller with field weakening enabled (there is no need to since you are directly controller power, just like a car or motorcycle throttle) so I don't know for sure. The throttle mid point and mid point current are also individually variable so the control can be tailored to desired "feel"

I've never seen field weakening draw any current (the controller can report this info back to a PC/android device while in operation) when I ride around at part throttle unless I was at high speed where field weakening was required to maintain the required speed (>40mph on my setup).

Sounds good. I need to get a pair to really find out. I'd love to get back to 20s for the better efficiency during acceleration and at low speeds and still be capable of real highway speeds. My only concern is feeding extra current for field weakening during long climbs where heat is my only concern. I'd really only need it on generally flat highway, which is seldom enough that a switch to turn it on only then would be preferable.

BTW, do you know if these controllers can handle running dual controllers using a single throttle? If you're confident they can I'll send you some double controller customers your way immediately.

John
 
I'm not sure if you could run two off of 1 throttle. I would think it's possible if the throttle is buffered, but I don't have a way to test myself. I'll ask Sabvoton what they think and get back to you John.

Each controller can do 6kw continuous according to the manufacturer and I've done 12kw bursts on a full pack. It has over temp protection. I was unable to heat one of these up beyond 35C the way I ride. They have MUCH more heat sinking than the Xie Chang setups + over temperature protection.
 
John, I'm sure you could build a throttle buffer if you need it. At these current levels the grounds will move due to the IR drop and that will affect throttle inputs differently at each controller. Since they are current based throttles they should tend to equalize. A differential amplifier can be used to re-reference the throttle voltage to the shifting ground reference at the second controller. I'd try it first without one, and if there are problems add it.
 
zombiess said:
They have MUCH more heat sinking than the Xie Chang setups + over temperature protection.
I'm also impressed with the sturdy design. Although of huge size, the controller is not very heavy.

The software could be much better though. It does not feel like a consumer grade software at all, but rather something that came out of a small electronics lab. It installs several National Instruments drivers, and could very well be based on LabView.

FYI there is no mention of the brand 'Sabvoton' anywhere on the outer casing. Nor is there any product number or other info. It's surprisingly anonymous...
 
I noticed the same thing on the software. It's very "generic". Interface design is very Chinese and could be a lot more friendly. The company appeared willing to make changes to it and firmware, but then nothing happened after I gave them several suggestions on improving it.

I'm tiring of this Chinese stuff. I'm slowly working my way towards designing my own controller. Been learning DSP design.

I'm never going to be happy with anything commercial, everything I've seen has issues. Many of the issues are poorly designed layouts which don't work at high power. This is the reason there are very few controllers that work at >100v. It's difficult to design for and no controller manufacturer I've seen has done a good job. Sevcon just barely squeaks by due to having good programability features (but everyone says they are hard to tune) and built in protections, but their layout is for maximized profits, not performance. Compromises.

I chose to sell these Sabvoton controllers because they have a good price per dollar for their features and performance. It's a much higher quality product than the Xie Chang controllers most are use to. The software is about a 3/10 for design / friendliness which isn't too bad considering the Xie Chang stuff is a 0/10 because it requires so much hex editing hacking to work with the hacked controllers which are being pushed way beyond their intended designs.
 
All of mine have the same sticker as well. I think the board on the inside says Sabvoton as well. I'll have to look at my tear down pics.
 
Alright, so they forgot to install the sticker on mine, or it is counterfeit :)

Did you notice how the software is zipped up in a folder structure that contains chinese characters?
It will refuse to run/install unless you rename it. Very user friendly indeed...
 
sven_nilsson said:
Alright, so they forgot to install the sticker on mine, or it is counterfeit :)

Did you notice how the software is zipped up in a folder structure that contains chinese characters?
It will refuse to run/install unless you rename it. Very user friendly indeed...

Funny that you mention the counterfeit issue. I thought I saw someone from Sabvoton on here mention that there were counterfeits out there that did not perform well. Details are fuzzy. If it is true I'd like to see the guts of them side by side, because what I see in the controllers I have look like there was some thought put into the design. That and I've worked directly with them to get changes made and watched them update the blog on their website as my requested changes were added.

Doing business with China is risky, so many frauds. One must be VERY careful. I've been burned for a few grand (not by Sabvoton).
 
incorrect info deleted.

Zombiess, can you tell give us a top speed comparison with field weakening on vs off? Does field weakening push you to normal no-load speed or even beyond it?
 
where did you see/read a wiring diagram with a field weakining cable?

with 20s a 26" Cromotor runs ~70/75 kph
with field weakining (max) same Bike runs 100kph.

so its near no load speed(w/o FW). But this is only for 20s. iam sure on 30s you dont get speed near no load ;P
 
Merlin said:
where did you see/read a wiring diagram with a field weakining cable?

with 20s a 26" Cromotor runs ~70/75 kph
with field weakining (max) same Bike runs 100kph.

so its near no load speed(w/o FW). But this is only for 20s. iam sure on 30s you dont get speed near no load ;P

Damn, up too late last night. I confused Boost with field weakening. The 1/3 increase in top speed is impressive though.

30s??? I didn't think they can do 30s. I want to go back down to 20s or maybe 22s. Since I require dual controllers I'm hesitant to buy first only to find out later that field weakening will kick in at times I don't want it, such as relatively high speed up steep hills. Maybe I'm just not understanding how it works, but I definitely don't understand the conditions in which it kicks in.
 
email Kathy from Sabvoton. Iam sure she(he?) can answer it or will clarify with devvelopers to give you that answer you want.

30s (125v) is the new generation. 96150 Model. Official up to 120v. But the 72150 can do also 24s (100v). Dont know if they run with 125v because MY 72150 see on a full charged 20s (84v) 86,7v.
If the new one see also 1,7v more. 30s will not work.(fully charged). Same with the 72150 trying 24s.
 
Hi John,

I suspect the conditions where field weakening is used (when it is configured) are not straightforward to predict as it depends on throttle demand, phase current, back EMF, load, current system voltage, etc. Perhaps instead the thing to do is make an indicator of real time FW current. The Sabvoton seems to provide this information via serial or bluetooth, so a display showing this would allow you to back off the throttle when you don't want to use it.
 
Is it possible to charge the battery through this controller with an inductor or motor windings?
 
megacycle said:
Is it possible to charge the battery through this controller with an inductor or motor windings?
+1
Few bigger AC system manufacturer do that and Adaptto is doing that as well. You still need at least purely but regulated PSU?
http://adaptto.ru/files/Maxcontoller_Manual_V1_EN.pdf page 13.
 
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