Lebowski's motor controller IC, schematic and setup manual

[zombiess]

You should see the looks I get from people when I try to explain why someone was unable to log in to their computer, I fix it and then they actually want me to answer their question of why which then leads to a very simple answer of the time sync between a server and domain controllers was off. If they actually ask me why after that I try to do my best layman's explanation of time sync, RTC clock drift, kerberos tickets, replay attacks, NTP and the different stratums and domain authentication. Usually by the time I get to the explanation of time sync (the first one) they ask me to stop and thank me. Most have now learned to just stop asking why because they get one of two answers from me.

1. I have no clue but it works now (this happens pretty often but I usually have some idea what caused the problem but don't want to get into details)
2. I fixed and know why, but do you really want to know the details?

I could probably write several pages explaining this to a lay person since it's a pretty simple concept, but you really should have some sort of base knowledge of security and time sync, real time clock drift and NTP protocol to really get it without setting aside an hour for me to go into details / examples. It's really amazing how important and complex just keeping the same time can be when you have servers spread across the globe, not to mention getting windows to actually listen and re-sync the clock when you tell it to and not just ignore your command.

A little off topic, but still relevant.

Back on topic:

Thanks Lebowski!

[Arlo1]

Ok so first question. Whats some good numbers for resistors Ra and Rb on the back emf sensing circuit page 8.
Now I was thinking about having my IC isolated from the main battery but it looks for this circuit its needs a common -.

Edit I forgot to mention for 80-200 v battery voltage.

[Arlo1]

Ok second question. On page 12 you mention setting the PWM frequency based dead time with a calc like this "PWM_freq is 1 / (50 * deadtime)"
But is dead time not more just a function of how fast your power-stage can switch. And pwm frequency is needed just high enough for the given inductance of the motor? eg. >inductance = < pwm frequency? You also mention to set the PWM frequeny with an oscilloscope? To set it with an oscilloscope what will I be wanting to watch? The current on one phase? Its best to ask now and look stupid rather then overlook something and cost my self a lot of time and money!

[Lebowski]

Ok so first question. Whats some good numbers for resistors Ra and Rb on the back emf sensing circuit page 8.
Now I was thinking about having my IC isolated from the main battery but it looks for this circuit its needs a common -.

Edit I forgot to mention for 80-200 v battery voltage.

For this part, I would make Ra 10 to 15 kOhm but make sure to get a good Watt rating (3 W or higher, 200V with 10 kOhm
is (200^2)/10000 = 4 Watt but it's switched with 50% on average -> 2W, take 3W to be safe). Rb, choose the same value as
Ra but you can use small 0.25Watt resistors. For the diodes I would use something like a cheap fast MBR150 (50 V, 1A schottky,
note that the voltage rating is not important, what matters is the forward voltage with (200/10k) = 20 mA current going through it).

If you have an optically isolated output stage the circuit does not need a common ground (I have an optically isolated output
stage and only tried common ground two weeks ago)...

[Lebowski]

Ok second question. On page 12 you mention setting the PWM frequency based dead time with a calc like this "PWM_freq is 1 / (50 * deadtime)"
But is dead time not more just a function of how fast your power-stage can switch. And pwm frequency is needed just high enough for the given inductance of the motor? eg. >inductance = < pwm frequency? You also mention to set the PWM frequeny with an oscilloscope? To set it with an oscilloscope what will I be wanting to watch? The current on one phase? Its best to ask now and look stupid rather then overlook something and cost my self a lot of time and money!

Page 12 was written keeping in mind that not everyone has an oscilloscope, I wanted to show a method
where you can setup the PWM correctly using only a simple cheap multimeter. Keeping this in mind, the
equation for PWM_freq of page 12 is a guideline.
Deadtime is a measure for how fast your output stage can switch. It doesn't make sense to use 100 kHz PWM
(10 usec period time) when you have a deadtime of 1 usec (with rising and falling edge taking 2 usec out
of 10 usec period time, you can see it's not very well balanced). Like you say, a short deadtime means your
output stage can switch fast meaning you can tolerate a higher PWM frequency (UNDER THE CONDITION YOUR
DRIVER STAGE DOES NOT OVERHEAT !!!!!)
If you have a low inductance motor you need a certain minimum PWM frequency meaning you need to have
a short deadtime. The output stage and its driver needs to match the motor requirements.
The "PWM_freq is 1 / (50 * deadtime)" equation means 4% of the period time is offered up to deadtime,
I think this is a good middle of the road guideline...
When you want to measure how good your drivers are doing, look at the gate-source signals of the output transistors.
The output signals (motor terminals) are not that interesting, here much more important is the shoot-through
current which you can measure with a multimeter in the battery line.
Make sure though you set the output polarity (active HIGH/LOW) correct first !

[Arlo1]

Ok second question. On page 12 you mention setting the PWM frequency based dead time with a calc like this "PWM_freq is 1 / (50 * deadtime)"
But is dead time not more just a function of how fast your power-stage can switch. And pwm frequency is needed just high enough for the given inductance of the motor? eg. >inductance = < pwm frequency? You also mention to set the PWM frequeny with an oscilloscope? To set it with an oscilloscope what will I be wanting to watch? The current on one phase? Its best to ask now and look stupid rather then overlook something and cost my self a lot of time and money!

Page 12 was written keeping in mind that not everyone has an oscilloscope, I wanted to show a method
where you can setup the PWM correctly using only a simple cheap multimeter. Keeping this in mind, the
equation for PWM_freq of page 12 is a guideline.
Deadtime is a measure for how fast your output stage can switch. It doesn't make sense to use 100 kHz PWM
(10 usec period time) when you have a deadtime of 1 usec (with rising and falling edge taking 2 usec out
of 10 usec period time, you can see it's not very well balanced). Like you say, a short deadtime means your
output stage can switch fast meaning you can tolerate a higher PWM frequency (UNDER THE CONDITION YOUR
DRIVER STAGE DOES NOT OVERHEAT !!!!!)
If you have a low inductance motor you need a certain minimum PWM frequency meaning you need to have
a short deadtime. The output stage and its driver needs to match the motor requirements.
The "PWM_freq is 1 / (50 * deadtime)" equation means 4% of the period time is offered up to deadtime,
I think this is a good middle of the road guideline...
When you want to measure how good your drivers are doing, look at the gate-source signals of the output transistors.
The output signals (motor terminals) are not that interesting, here much more important is the shoot-through
current which you can measure with a multimeter in the battery line.
Make sure though you set the output polarity (active HIGH/LOW) correct first !

So more or less in my case I need to start the other way. Start with PWM frequency at X (im thinking 40 khz) then work back from there make sure my dead time works out to be 4% of X and set my current resistors to make the On Of time work with X frequency, and finaly scope my out put stage to make sure it can handle X frequency. Other wise replace what part(s) I need to make them relaible at X frequency.

[rolf_w]

yesterday I received the "Albis" ; thx Bas !! now I have to build a power stage (ca. 100V / 100A_peak needed) for which I require input/feedback from the experts here. I'd like to start with Shane Colton's 3ph Duo (v2.1 / v3.1) design for the power stage (http://scolton.blogspot.com/p/motor-controllers.html and http://web.mit.edu/scolton/www/3phduo.pdf). He happily uses the http://ixapps.ixys.com/DataSheet/GWM100-01X1.pdf which seems a very cost effictive full bridge (ca. 20USD?)



If this or a similar power stage is readily available I'd prefer to buy it. If I'd start from scratch but keep with the GWM100-01X1 which driver would be suitable? anybody has experiences with gate transformers?

r

[Arlo1]

yesterday I received the "Albis" ; thx Bas !! now I have to build a power stage (ca. 100V / 100A_peak needed) for which I require input/feedback from the experts here. I'd like to start with Shane Colton's 3ph Duo (v2.1 / v3.1) design for the power stage (http://scolton.blogspot.com/p/motor-controllers.html and http://web.mit.edu/scolton/www/3phduo.pdf). He happily uses the http://ixapps.ixys.com/DataSheet/GWM100-01X1.pdf which seems a very cost effictive full bridge (ca. 20USD?)



If this or a similar power stage is readily available I'd prefer to buy it. If I'd start from scratch but keep with the GWM100-01X1 which driver would be suitable? anybody has experiences with gate transformers?

r

rolf.
IM no expert but I think I have a good understanding of this. When you see a spec like 90amps max and 100volts max for a mosfet or H bridge etc. It means You will NEVER SEE THOSE NUMBERS. Here is why when the controller is PWMing the fets the amperage builds as the pwm fet is in on time and it builds till the controller says long enough for what ever reason (current based or pwm time is up etc) the point being when the controller says long enough the amperage has to be = or < the max of the fet rating or the fet will be destroyed. SO if you were realy good at setting up your power stage and all the settings in the controller you might get lucky to get the amps to build just to the max of the fet rating then shut off and if you acomplish this you will still get < the max of the fet ratings for phase amps. This is because the pwm will feed a pulse of up to or less then the fet max amp rating then shut off and the inductance of the motor will smooth out the current to an avarage of the on time vs off time. Make sense? Anyone think im wrong on this let me know but im pretty sure this is why many people look at the fet ratings as un realistic!

[Lebowski]

I kind of like the idea of this full bridge 'chip', it's compact design keeps many of the stray inductances in check.
About the 100A, I can imagine this is the maximum rated average current but that it can take much more A in peak ?

About the driver, I'm playing around with 4115's driven by the NCP5181 and it looks good so far. Driving single
4115's (for a 6 FET controller) it easily reaches 50kHz PWM freq with negligible shoot through even with sub 100 ns deadtime (66 V).
The gate charge of the full bridge chip looks to be about the same...

[whatever]

question from a novice:
xie cheng controller ( infineon chip or newer one) you cant read what values are already set in the controller ( phase amps etc etc)( unless someone has worked it out) will it be possible to read what values are already set in this chip?

[c_a]

Reveiced the chip today, many thanks @L.
Now I printed the manual and tomorrow I will order two or three mitsubhisi fm600tu-3a mosfet moduls

what input capacity do I need for 60V and 200amps and 120V and 450amps?

[Arlo1]

Reveiced the chip today, many thanks @L.
Now I printed the manual and tomorrow I will order two or three mitsubhisi fm600tu-3a mosfet moduls

what input capacity do I need for 60V and 200amps and 120V and 450amps?

These moduals mention drain current rms 300a and peak pulsed drain at 600a so would that meen you can pulse them to =or< 600 amps during pwm...?
They do look nice 110mm x 90mm is a nice size but they are slow switching... They have low rdson for a 150v product. Hmmmm I am interested to see what real world numbers we can get from them.

[Njay]

Fantastic work Lebowski, congratulations!

[Lebowski]

question from a novice:
xie cheng controller ( infineon chip or newer one) you cant read what values are already set in the controller ( phase amps etc etc)( unless someone has worked it out) will it be possible to read what values are already set in this chip?

yes there's no data protection... which also means you can totally mess it up

[whatever]

what I mean is, if you set certain parameters ( say phase amps for example), is it possible to read from the controller ( via computer)
what value you've set previously?

[Lebowski]

what I mean is, if you set certain parameters ( say phase amps for example), is it possible to read from the controller ( via computer)
what value you've set previously?

In the setup menu it gives the value that is currently set so you can see which value
is being used right now. It does not remember the 'history' or past settings of a value.

[nieles]

does the controller have a e-brake function, like you see on many of the chinese controllers?

this way you wont be able to brake and power the bike at the same time, a nice safety feature if your throttle gets stuck WOT for some reason.

(this could be done with the reset switch, but i don't know if the controller likes it to be reset all the time?)

[Lebowski]

does the controller have a e-brake function, like you see on many of the chinese controllers?

this way you wont be able to brake and power the bike at the same time, a nice safety feature if your throttle gets stuck WOT for some reason.

(this could be done with the reset switch, but i don't know if the controller likes it to be reset all the time?)

I don't know what an e-brake function is, but if you need some sort of safety switch to bypass the
throttle... You can give a reset as you suggest, this will turn off all the FET's and let the motor
spin freely until e-rpm has dropped until almost standstill. Another option is to connect a switch
between the throttle input (pin 9 or 10) and ground. The 1000 ohm resistor between the throttle
(hall or potentiometer) will limit the current, you can increase this resistor to 2200 if you want to
limit the current even further.
The difference between the two methods is that issuing a reset will put the controller back in
drive 0, something which it will only transition out of when the motor is close to standstill.
Shortening the throttle to ground is the same as closing throttle, when you remove the short
you regain immediate throttle response.

How is it going with your controller build ?

[nieles]

I don't know what an e-brake function is, but if you need some sort of safety switch to bypass the
throttle... You can give a reset as you suggest, this will turn off all the FET's and let the motor
spin freely until e-rpm has dropped until almost standstill. Another option is to connect a switch
between the throttle input (pin 9 or 10) and ground. The 1000 ohm resistor between the throttle
(hall or potentiometer) will limit the current, you can increase this resistor to 2200 if you want to
limit the current even further.
The difference between the two methods is that issuing a reset will put the controller back in
drive 0, something which it will only transition out of when the motor is close to standstill.
Shortening the throttle to ground is the same as closing throttle, when you remove the short
you regain immediate throttle response.

How is it going with your controller build ?

the e-brake is basicly what you discribed, it cuts the throttle when you apply the brake (there are brakes with build-in reed switches)

what would be awsome, is to have a switch like the reset, but with the folowing function:
when connected to gnd or floating, turn all fets off
when connected to 5v again it will return to the previous drive (0,1,2 or 3)
before enabling the throttle, wait for the throttle to be zero.(but not for the motor to be near zero rpm)

(pin 22 could be used for this?)

about my controller build;
i made some small pcb's for my current sensors this weekend, so i should be able to get the controller working on the breadboard sometime this week.

[LegendLength]

Do I understand correctly that this will allow smooth regen rather than on/off style of infineon controllers? If that's the case I'm sure many of us on the forum would love to purchase a fully made controller for our typical hub motors that has that feature. If it was combined with a ready-made analog brake lever they would sell like hotcakes imo.

[Arlo1]

Do I understand correctly that this will allow smooth regen rather than on/off style of infineon controllers? If that's the case I'm sure many of us on the forum would love to purchase a fully made controller for our typical hub motors that has that feature. If it was combined with a ready-made analog brake lever they would sell like hotcakes imo.

You have to understand this is going to be for a $1000-2000 type controller right? This might be something we can get to happen as a kit but even then it will not be cheep!

[Arlo1]

I just recived the two chips you sent me and gordo. Thanks Lebowski! I am excited to get all this working!

[Lebowski]

Do I understand correctly that this will allow smooth regen rather than on/off style of infineon controllers? If that's the case I'm sure many of us on the forum would love to purchase a fully made controller for our typical hub motors that has that feature. If it was combined with a ready-made analog brake lever they would sell like hotcakes imo.

In Kelly-speak: it has variable-strength regen

I haven't really thought about making controllers or kits yet, first I want to see how it works with other motors,
this is why I emailed some chips around to interested people...

[LegendLength]

You have to understand this is going to be for a $1000-2000 type controller right?

Ahh sorry I didn't realize that.

[Lebowski]

You have to understand this is going to be for a $1000-2000 type controller right?

Ahh sorry I didn't realize that.

me neither