Search found 845 matches

by HighHopes
Dec 06, 2017 7:00 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15

They use software to make the throttle work for the full range from a stop but when you let off after you are moving the first part of the throttle becomes variable Regen. just want to clarify so i understand. there are 3 things about tesla you like - throttle feels linear from 0 to max - when you ...
by HighHopes
Nov 15, 2017 6:27 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

i like the part where he says "i been at this 3.5 years, got a stack of blown parts in the back" ... keep'n it real 8)
by HighHopes
Nov 12, 2017 8:05 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

yes i know what spread spectrum is. maybe in the digital world where noise is low it's good strategy. in power world its not good becuase if you spread out noise over larger spectrum all you get is a larger spectrum of noise ALL of which exceeds your allowable limits (DO-160, MIL-STD 704) because th...
by HighHopes
Nov 07, 2017 9:35 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

no because we want to know where the frequency will be exactly at high energy (not spread out with lower) so we can taylor a single highly tuned filter to suit. that's an LC hardware filter. hopefully i understood your question. if you could meet DO-160 or MIL-STD 704 with spread spectrum and NO har...
by HighHopes
Nov 05, 2017 8:46 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

I would love to spend time in an EMI chamber. so long as you don't get claustrophobic it can be very interesting. and i agree with luke, its hard to ascertain "the rules" of EMI and noise.. the subject seems to have a chaotic life of its own. what i learned the hard way is to do absolutely everythi...
by HighHopes
Nov 04, 2017 10:52 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

encoder manufacturers will say how they want their equipment grounded and i see it in their document as grounded at both ends. ya you definitely getting serious ground loop current if a resistor in this ground cable helps. this resistor with the current flowing through it will make your resolver's r...
by HighHopes
Sep 02, 2017 8:50 am
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

The only properly shielded connectors I used are usb, not quite appropriate for this application the ones i use are gigantic, metal D-sub. lets look around, see what we can find. another option, and i just put this out there... what if the A/D were on the sensor side and from there it is fiber to b...
by HighHopes
Sep 01, 2017 7:07 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

ya, totally agree snap the PCB and make wired connection between sensor and brain board. this cable is going to be noisy.. you should consider, unless you already did and i didn't see it, to have a connection point for cable shield on both ends. weither it gets connected on both ends or not is debat...
by HighHopes
Aug 31, 2017 11:44 am
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

the current sensor busbar will be affixed to the IGBT and presumably an insulated mount just before cable connection out to motor. the other end of the PCB has 2 screw holes to secure it to something. that something.. hopefully, is the same thing as the insulated mount just before cable connection. ...
by HighHopes
Aug 29, 2017 6:55 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

@zombees, yep. Quality torque cell on the coupling bushing is helpful in this regard but is probably outside the normal for garage tools. Also machine bonding both dynno and your car chassis and grounded.
by HighHopes
Aug 17, 2017 8:35 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

ahhhh..... github. i been avoiding you for years cause i tend not to work in teams so i do all my revision control myself. but ya, i can see its usefulness. lets say i wanted to make a change to the schematic you posted in github. you ok if i do that? i don't know how to do this yet in github.. will...
by HighHopes
Aug 14, 2017 8:03 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

If you have something better then the oem LEAF it will be better the new leaf cells are 10c peak rated old cells are 3c peak rated. whoaaa! that's significant improvement! dunno what the going rate is for salvaged new leaf but sounds like its worth it. i have my eye on an old Volt battery near me...
by HighHopes
Aug 14, 2017 7:59 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

PaulD wrote:Manganin is often Electron Beam Welded  to copper for this purpose.
sounds like a process that is not easily DIY .. i'm trying to find ways to make all this high power EV stuff "doable" to a highly interested practitioner on a shoestring budget and typical bench tools only.
by HighHopes
Aug 14, 2017 7:49 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

marcus $25/unit, that's more than reasonable. linear up to 1400A and then non-linear in "overdrive" mode that's fine. you can do some math to linearize that portion or at least improve. do you have the SCH & BOM for this? we can do some analysis and change the design if needed to suit our purpose. t...
by HighHopes
Aug 09, 2017 7:44 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

t says so for 10MHz clock, but the exact same part has a 20MHz variant, so it would jump to 40khz at 14bit. There is another one that the clock pin is an input so you set the freq, up to 21mhz. 14 bit its probably too much, I usually use 12bit so it shouldn't be hard to reach 20% extra bandwidth in...
by HighHopes
Aug 08, 2017 9:36 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

This is a tesla model s current sensor.
ya, that's just copper.. not a resister per say. no way you can do anything so high amps with an actual shunt resistor.

the way i'm doing high amps is different (and can't measure DC), but also no resistor. can't be done with a resistor.
by HighHopes
Aug 08, 2017 9:25 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

having to run 4 wires to a current sensor and use 2 isolated supplies or one with dual outputs seems complicated and unnecessary i think in the end you'll find that you need the 4 wires and an isolated supply. the problem is the current sensor is external to your main control board AND the current ...
by HighHopes
Aug 07, 2017 5:19 pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 47
Views: 1946

Re: Current Sensors How to select a good one or roll your ow

just some re-wording and quantitative numbers and comments/feedback. these are just for ball-park, if you have different number in mind put your values. i also added #9 1 bandwidth: >50kHz 2 group delay (latency) including signal conditioning: 10ms 3 low cost: <$50 per piece 4 small and compact.: <2...
by HighHopes
Aug 06, 2017 8:14 pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 114
Views: 7135

Re: OSHW TO247 IGBT watercooled laminated half-bridge

i've never used shunt for high power. i don't believe you'll get the SNR necessary, especially at low to mid range amps (at very low, probably have to turn current loop off). anyway, i did look into it a few months ago for a high amp project. i'll post what i found in your other thread which relates...
by HighHopes
Jul 28, 2017 7:02 pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 114
Views: 7135

Re: OSHW TO247 IGBT watercooled laminated half-bridge

wait till u see the price of the flexible PCB ;P
by HighHopes
Jul 28, 2017 5:44 pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 114
Views: 7135

Re: OSHW TO247 IGBT watercooled laminated half-bridge

did u use seeeds to fab the board too? 1oz is good pricing, but 2oz is more than 10x?
by HighHopes
Jul 14, 2017 6:44 pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 114
Views: 7135

Re: OSHW TO247 IGBT watercooled laminated half-bridge

good point. you probably don't need that diode at all if have low voltage transients anyway. i built many high power gate drivers without it.
by HighHopes
Jul 12, 2017 9:00 pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 114
Views: 7135

Re: OSHW TO247 IGBT watercooled laminated half-bridge

what i remember is that tesla controls the gate voltage to manage switch time which influences voltage transients. if that's the one you're talking about, i don't know how they can patent this as its an idea been around for ages. it was called dynamic gate driver back in the day, almost 20 years ago...
by HighHopes
Jul 11, 2017 10:48 pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 506
Views: 38233

Re: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp

Luke, since you will visit Arlo in BC why not repeat the Cross Canada trip that Justin did in 2008 and make it up to Montreal for the Formula-E with your DSR and 18kW charging power! =)) after all that's just 5000km :shock: I'm kidding! as well.. but that would be cool.. 8) Doc stop by my place alo...
by HighHopes
May 10, 2017 7:39 pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 114
Views: 7135

Re: OSHW TO247 IGBT watercooled laminated half-bridge

glad we feel the same way. didn't tesla put all their patents up for open use? perhaps they don't mind if we copy... i know of a battlebots builder that uses discretes sintered onto copper sheets. lab tests show impressive results. there's definitely something worth investigating here or just drop i...