Search found 860 matches

by HighHopes
Nov 02 2019 9:35am
Forum: Motor Technology
Topic: Sensorless From Standstill (SFS) explained
Replies: 24
Views: 2991

Re: Sensorless From Standstill (SFS) explained

now that's a nice post! i was there when the aerospace engineers developed and patented realistic methods of doing zero start full torque sensorless (before electric vehicles were a "thing"). i've read pretty much all the patents and was involved in some of the development. using negative sequence c...
by HighHopes
Oct 31 2019 8:47pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 414
Views: 88560

Re: Axiom: a 100kW+ motor controller

the beauty of all this hockinsk, is that its open source. so if people want to try it out using the default code that already supports most of what you're talking about then you're starting from a good spot. a super enthusiastic DIY'r could in theory set up a multi-motor EV, multi Axioms, one gas pe...
by HighHopes
Sep 01 2019 5:54am
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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

Lebowski wrote:
Sep 01 2019 3:52am
Man, 250c, they'll be empty in 14 seconds !
he only needs 9.2s :)
by HighHopes
Aug 12 2019 8:35pm
Forum: Motor Technology
Topic: BESC - beefed up VESC motor controller for high power ebikes
Replies: 142
Views: 22973

Re: BESC - beefed up VESC motor controller for high power ebikes

Peters.. before you get bent out of shape about ringing on a double pulse test. put both diff probes on ONE location, say IGBT gate. then repeat the double pulse. notice you still get ringing? that's basically your probe leads.. it represents the portion of the double pulse scope test results that a...
by HighHopes
Aug 12 2019 8:31pm
Forum: Motor Technology
Topic: BESC - beefed up VESC motor controller for high power ebikes
Replies: 142
Views: 22973

Re: BESC - beefed up VESC motor controller for high power ebikes

TD350E sadly yes is going to be, if not already, obsolete. ST got lucky with that one back in the day when they made the gate driver cause it actually worked remarkably well. this is going back some 15 years. for the low to mid level power, this gate drive even with a boost stage was the goto. now-a...
by HighHopes
Jun 01 2019 9:38pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 414
Views: 88560

Re: VESC controller: Check Axiom datasheet!

Its great that you are regulating 1A current with +/-425A current sensors.
ditto. that's impressive
by HighHopes
Apr 14 2019 10:12am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 414
Views: 88560

Re: VESC-controller: Axiom hardware released!

that sounds a lot like what was commonly used in commercial aircraft. a separate exciter and neutral connected motor. it was done this way so you could avoid using magnets in your motor thus allowing you to instantly disable power generation in case of a fault. the neutral connection was there so yo...
by HighHopes
Apr 12 2019 8:39pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 414
Views: 88560

Re: VESC-controller: Axiom hardware released!

Ya it's exciting! a good working team, one founded through common interest right here on ES! one of the things we learned along the way is how each of us contributes to the overall project in different ways making the whole a little better than it otherwise would've been. in this light, we like to k...
by HighHopes
Jan 09 2018 8:58pm
Forum: Motor Technology
Topic: OSHW TO247 IGBT watercooled laminated half-bridge
Replies: 144
Views: 23861

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 7:26pm
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 8710

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 8:38pm
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 8710

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 10:01pm
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 8710

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 11:32am
Forum: Motor Technology
Topic: Mid drive vs Hub Motor for 10000 watt project
Replies: 95
Views: 11452

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 11:21am
Forum: Motor Technology
Topic: 144Vdc EV Charger
Replies: 78
Views: 8710

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 10:14am
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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 7:00pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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 6:27pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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 8:05pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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 9:35pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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 8:46pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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 10:52pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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 8:50am
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 56
Views: 9524

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 7:07pm
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 56
Views: 9524

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 11:44am
Forum: Motor Technology
Topic: Current Sensors How to select a good one or roll your own.
Replies: 56
Views: 9524

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 6:55pm
Forum: Motor Technology
Topic: Hi power inverter for Nissan leaf motor. Dyno's 302.3hp p15
Replies: 577
Views: 103981

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.