Search found 852 matches

by HighHopes
Jan 09, 2018 8:58 pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 144
Views: 9786

Re: OSHW TO247 IGBT watercooled laminated half-bridge

looks like a decent chip if its <$6. but don't follow their layout advice, yikes :shock: also, i don't know why they call it active soft shut down.. its basically not much different than your two-step turn off. other chips do this just as well. and there is no transient voltage protection here which...
by HighHopes
Jan 04, 2018 7:26 pm
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 5483

Re: 144Vdc EV Charger

there was a time when i had a handy spreadsheet (that i spent forever making) that was used also by magnetics manufacturing plant here in canada. could calculate up a design using any core material, supermendour, metglass, ferrite.. any geometry. it was good. quick. sadly, i don't know what happened...
by HighHopes
Jan 03, 2018 8:38 pm
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 5483

Re: 144Vdc EV Charger

the original post of this thread shows an isolated topology. take it easy... its there. also, the original post if you look at the picture of the schematic the input is PFC stage switch driving a transformer and could be synchronous rectification output if you changed the diodes for mosfets on the r...
by HighHopes
Jan 02, 2018 10:01 pm
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 5483

Re: 144Vdc EV Charger

very likely the switching freqency will be >=100khz because this sort of application requires a lot of power magnetics and you want to keep that small. once the design is done for 400V output (for example) you'll have all the math and capability to spin the design in a modular way to get any output ...
by HighHopes
Dec 31, 2017 11:32 am
Forum: Motor Technology
Topic: Mid drive vs Hub Motor for 10000 watt project
Replies: 93
Views: 2611

Re: Mid drive vs Hub Motor for 10000 watt project

every major city with 100K population will have at least one motor re-wind shop. check the yellow pages (oops.. just dated myself). they can re-wind your motor for you if you don't know how to do it yourself. for the same motor, what you'll get is the same power.. increase the voltage (motor speed) ...
by HighHopes
Dec 31, 2017 11:21 am
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 5483

Re: 144Vdc EV Charger

its almost time to re-vamp this thread. make it bi-directional, higher power.... ability to stack in parallel. i don't know about the DC voltage though. this project was for 144Vdc because i thought it would be hard to make and to fit a 400V DIY pack from re-cycled leaf or chevy volt. 2 years later,...
by HighHopes
Dec 21, 2017 10:14 am
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 512
Views: 44482

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

They deliberately heat the motor to heat the cab....
seems so obvious now that you point it out! lol. brilliant
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: 512
Views: 44482

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: 512
Views: 44482

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: 512
Views: 44482

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: 512
Views: 44482

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: 512
Views: 44482

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: 512
Views: 44482

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: 55
Views: 3011

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: 55
Views: 3011

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: 55
Views: 3011

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: 512
Views: 44482

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: 55
Views: 3011

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: 512
Views: 44482

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: 55
Views: 3011

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: 55
Views: 3011

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: 55
Views: 3011

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: 55
Views: 3011

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: 55
Views: 3011

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: 55
Views: 3011

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...