Search found 831 matches

by Njay
Aug 15 2015 9:38am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Arlin, do you have this trace but for the turn on part, in as much detail (zoom on time and voltage) of the switching on as possible (with info on time and voltage scales)?
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by Njay
Aug 11 2015 6:01am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

If that's at your target max voltage and current, it looks good enough to me, you ain't gonna get to zero inductance anyway...
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by Njay
Aug 07 2015 12:49pm
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Assuming the current is OK, I don't see any "aliens" on your switching. Yes, you have a lot of ringing on turn off, but that looks normal for certain combination of switching time and layout... could probably be improved, but the structure looks "normal" to me. (...)Thanks for the advice I will see ...
by Njay
Aug 06 2015 5:24am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Or even better from a security stand point, is to use the serial port, if you have any free (I can get you some "core code" for the serial port handling). If you ever go with the pots you need to make sure the connections are sound and remember to dial back at the start of each test :mrgreen:
by Njay
Aug 05 2015 5:23pm
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Using the include I mention you should have access to _delay_us, but this is in pure AVR toolchain, which the Arduino uses, but does mysterious things on top :), so nevermind, it's not that important; if you really want we can discuss it, but I think you would benefit more from having user configura...
by Njay
Aug 05 2015 6:30am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Ok so I wrote (modified other) code for an Arduino UNO and it works perfect except when using delay microseconds it adds 10uS to all the pulses I will be able to work with that no problem. A more precise function would be _delay_us() from #include <util/delay.h> . If you want the lowest jitter poss...
by Njay
Aug 04 2015 6:08pm
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Hey, cool :) . I don't have photovoltaics, but I have hot water panels. Those roof tiles look like cork, what material are they?
by Njay
Aug 03 2015 9:55pm
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Your cap is almost one year over spec'd shelf life (I suppose that's what they mean by "self life"), you should put it to work asap :)
by Njay
Aug 03 2015 7:01pm
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

5kA, that's what the datasheet said. its also a good sign when the datasheet actually writes something to that effect because then you know the internal structure was designed to handle fast charge/discharge (unlike electryolytic which is not). also, this is made in USA so 5kA is probably the minim...
by Njay
Aug 03 2015 5:47am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

HighHopes wrote:(...) Electronic Concepts Unlytic type UL30, 400uF, 400Vdc, ESR = 0.0037, ESL = 30nH, capable of just under 5000A peak. (...)
Ehhh... 5KA with 3.7mOhm, are you sure?
by Njay
Aug 02 2015 10:04am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Gentlemen, start your engines! (I know, I know! They're already started :mrgreen: )
by Njay
Jul 31 2015 9:53am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

This is how I see it. Make the times run-time adjustable. That way you can control the peak current you're testing at, and you'll want to start conservatively and go up as long as the test results show everything ok (such as no exaggerated voltage transients). The interval and 2nd pulse should be so...
by Njay
Jul 22 2015 4:36am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Yes I never spent enough time with the scope testing the circuit before but now I have my head wrapped around it better and understand the importance of testing before running it. Did you skip over verification / tuning on the bench? I love testing on the bench, I learn more every time I do it. Tot...
by Njay
Jul 17 2015 6:56pm
Forum: Motor Technology
Topic: 15A gate with negative bias and differential PWM input
Replies: 12
Views: 2170

Re: 15A gate with negative bias and differential PWM input

This type of isolators is usually very easy to use instead of optos: http://www.silabs.com/Support%20Documents/TechnicalDocs/Si841x-2x.pdf I don't know if it suites or app better or not than optos, but the general specs look good (1 or 2pF in-to-out @ 1MHz depending on package, HighHopes). I've used...
by Njay
Jul 09 2015 9:05pm
Forum: Motor Technology
Topic: Just bougth an 8KW dc motor
Replies: 10
Views: 3512

Re: Just bougth an 8KW dc motor

b 8)
by Njay
Jun 22 2015 7:17pm
Forum: Motor Technology
Topic: The significance of switching losses on commuter Wh/km?
Replies: 14
Views: 1968

Re: The significance of switching losses on commuter Wh/km?

I think Alan sums it up pretty nicely. Anyways, your calculations are irrelevant. You would need to measure tr and tf in the controller. Those times from the datasheet are not using your controller's FET drivers, nor current limit, etc etc. One way to greatly reduce dissipated power on your controll...
by Njay
Jun 20 2015 11:34am
Forum: Motor Technology
Topic: The significance of switching losses on commuter Wh/km?
Replies: 14
Views: 1968

Re: The significance of switching losses on commuter Wh/km?

From a theoretical point of view, you can approximate switching losses of one FET in an inductive switching application, by excess, by (this approximation is actually based on the idealized switching diagram as in fellow's post) Pd(sw) = 0.5 x Vds x Id x (tr + tf) x Fsw So, in a controller where you...
by Njay
Apr 17 2015 1:20pm
Forum: Motor Technology
Topic: Agni motor tuning and racing
Replies: 123
Views: 25556

Re: Agni motor tuning and racing

sure
by Njay
Apr 17 2015 11:40am
Forum: Motor Technology
Topic: Agni motor tuning and racing
Replies: 123
Views: 25556

Re: Agni motor tuning and racing

I have 1 or 2 docs about the b&s etek but no mention of "tuning".

----

Someone just brought this to my attention:
http://www.picoamps.de/automotive/en/pr ... en.htm#hdk
by Njay
Apr 08 2015 6:36pm
Forum: Motor Technology
Topic: Where to get a drive sprocket to fit an eTek/Mars
Replies: 33
Views: 5333

Re: Where to get a drive sprocket to fit an eTek/Mars

I never got to try my etek, it has a vibration issue that I haven't yet analyzed and meanwhile I found a 2nd hand Agni for a reasonable price and put the etek on a corner until I have some time for it.
by Njay
Apr 03 2015 6:13pm
Forum: Motor Technology
Topic: Sevcon Gen4 Size 6 teardown pics
Replies: 23
Views: 7171

Re: Sevcon Gen4 Size 6 teardown pics

I sure would like to know exactly how do they keep the Irr's consequences under control with those FETs at those controller's specs.
by Njay
Apr 02 2015 6:11am
Forum: Motor Technology
Topic: Exploding FETs
Replies: 26
Views: 3524

Re: Exploding FETs

Get us some pics of exploded/burnt FETs too :)
by Njay
Apr 01 2015 4:56am
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Yeah, looking really good :)!
by Njay
Mar 31 2015 7:47pm
Forum: Motor Technology
Topic: Arlo's power stage Leaf controller runs and drives page 103
Replies: 2595
Views: 245902

Re: Arlo's power stage.... New pics on page 78

Yellow is collector and emitter. Ok, you're using IGBTs. You measured C-E with flying leads too or scope probe, tip and GND clip directly on the module's C-E contacts (I don't know if your IGBT module(s) have them side by side, although I would assume yes)? Just trying to understand exactly how/whe...