Search found 149 matches

by thorlancaster328
Mar 06 2021 12:56am
Forum: Motor Technology
Topic: What controller for 72v, 100+ amps?
Replies: 12
Views: 339

Re: What controller for 72v, 100+ amps?

The additional wire does not go through the current sensor loop. When current flows, some of it flows through the original wire and some now flows through the new wire you just soldered on. Therefore the sensor reads less current than is actually flowing, and the controller increases phase current t...
by thorlancaster328
Mar 05 2021 12:24am
Forum: Motor Technology
Topic: 10kW BLDC motor controller up to 90V and 200A with sensorless FOC - build thread
Replies: 28
Views: 735

Re: 10kW BLDC motor controller up to 90V and 200A with sensorless FOC - build thread

That's a lot of power in a very small area. Looks really professional for home-etched circuit boards. :thumb: For higher power levels you'll likely need more cooling - JB-welding a heatsink to the bottom of the case wouldn't be a bad idea. I really like the layout of this. The next version of my con...
by thorlancaster328
Mar 04 2021 11:35pm
Forum: Motor Technology
Topic: What controller for 72v, 100+ amps?
Replies: 12
Views: 339

Re: What controller for 72v, 100+ amps?

Does your current controller get hot when running at its existing current limit? If not, then just beef up the shunt(s) (cover 1/3 of it with solder), put new thermal compound behind the MOSFETs, and go for it. If it uses current sensors, route wire (2 gauges thinner than the existing wire) in paral...
by thorlancaster328
Feb 27 2021 11:36pm
Forum: EBike Technical
Topic: Arduino Nano Cycle Analyst (and other) companion TidBits
Replies: 52
Views: 1059

LVPS regulators, etc

BTW, the LM5107 info I can find says it is a gate driver. https://www.ti.com/product/LM5107 How would that be used to make a simple DC-DC? (I know basic electronics, and "misuse" things successfully a fair bit of the time, but I R Not an Engineer so I don't know what to do with that kind ...
by thorlancaster328
Feb 27 2021 5:34pm
Forum: EBike Technical
Topic: Arduino Nano Cycle Analyst (and other) companion TidBits
Replies: 52
Views: 1059

Re: Arduino Nano Cycle Analyst (and other) companion bits and bobs

You don't need near that much bandwidth unless you were trying to play music through the throttle line. Sure it would work but it'd be 5x the board space and cost at least 10x as much as the low-bandwidth RC filter. If your controller could respond to a 100hz bandwidth throttle signal, the RC filter...
by thorlancaster328
Feb 27 2021 1:46pm
Forum: EBike Technical
Topic: Arduino Nano Cycle Analyst (and other) companion TidBits
Replies: 52
Views: 1059

LVPS regulators, etc

About a year ago I was working on a similar project - https://github.com/thorlancaster/electric-bike-controller . It was a much more complex project than this. It served as a replacement as a cycle analyst, not an addition to it. It also communicated across several Arduinos via an opto-isolated Seri...
by thorlancaster328
Feb 25 2021 11:39pm
Forum: Motor Technology
Topic: 3 phase without 6 switches
Replies: 12
Views: 302

Re: 3 phase without 6 switches

The coils in a motor have significant inductance. If you put the diodes like that, the transistors would be able to get a current flowing in the coils, but the current would take a long time to stop flowing with no way to speed it up. Trying to spin a motor wired like this would be a disaster. All o...
by thorlancaster328
Feb 24 2021 4:23pm
Forum: Vendor Relations Corner
Topic: Vector Ebikes taking >2 weeks to ship - Anyone else with this experience?
Replies: 4
Views: 246

Re: Vector Ebikes taking >2 weeks to ship - Anyone else with this experience?

Vector just shipped yesterday and DHL now has the package. 2½ weeks to ship isn't that bad if you consider other vendors, I just wish they would have been more forthcoming about the shipping time.
I'll post an update when the parts arrive.
by thorlancaster328
Feb 24 2021 4:13pm
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

I started from complete scratch (with no example papers to read) and coded in Assembly... Impressive that you got that sort of performance from relatively cheap hardware. I have very little ASM experience and wouldn't even touch an assembly project of that magnitude. ... With Divisional Basketball ...
by thorlancaster328
Feb 24 2021 1:02pm
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

The only thing more impressive than getting this to work is that it's only taken you a few days to code and it's literally a few weeks since I was first making comments on your schematic That's the beauty of using Arduino for something like this. All of the boilerplate initialization and low-level ...
by thorlancaster328
Feb 24 2021 12:29pm
Forum: Motor Technology
Topic: How to (not) kill FETs (on custom VESC)
Replies: 17
Views: 314

Re: How to (not) kill FETs (on custom VESC)

Have you put an oscilloscope on it? A lot of things that can kill FETs require an oscilloscope to see. Some things to check for are: Excessive ringing due to insufficient gate resistor - causes voltage spikes that can kill FETs Inductive or miller-induced turn-on - causes shoot through which kills F...
by thorlancaster328
Feb 24 2021 3:18am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

Got sensorless from standstill working. Haven't made much external progress, a lot of it was refactoring the messy ADC code into something more manageable. After I get the 20KHz pilot tone, the state machine, and initial position detection working, I will have something quite promising. @Lebowski Pr...
by thorlancaster328
Feb 23 2021 11:51pm
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

RFNoise5v.jpg I've found the reason why my ADC values are usually spot-on but sometimes are several measured amps off. The 12v-5v SMPS is spewing bursts of 100MHz RF noise onto the 5v line and everything it's attached to. Attaching additional decoupling capacitors doesn't help that much. The ferrit...
by thorlancaster328
Feb 23 2021 2:51pm
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

@Lebowski from what I understood about your paper, it appears that you are using external components and advanced math to filter the signal to reduce the amount of ADC bandwidth needed. I can get away with much simpler mean and median calculations because my ADC can take ~800k samples per second wit...
by thorlancaster328
Feb 23 2021 2:32pm
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

My proposed method of initial position detection does not require that the rotor is moving. With high enough phase currents, the change in inductance with respect to current will do two things. 1: It will offset the mean of the sampled currents. The greater slope (less inductance) will be on the sid...
by thorlancaster328
Feb 23 2021 3:17am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

The board layout of the 24-FET will be similar to the current 12-FET, two copies mirrored along the long axis The board layout of the 48-FET will also be mirrored along the long axis, but I won't design/build that one until I've sold at least a couple 24-FET ones. Since I'm essentially building copi...
by thorlancaster328
Feb 23 2021 3:12am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

Guess I found my next FET :bolt: :bolt: :bolt: The IPP023N10N5 is TO-220 FET with only 2 mOhm typical @ 100 amps and 10 volts. Gate capacitance is only 10 nf - Current UCC drivers could handle up to a 36-FET board. Avalanche characteristics look great - Max avalanche current is 100 amps/FET for 10 u...
by thorlancaster328
Feb 23 2021 2:06am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

For the initial 180 degree detection I also tried a simple method earlier: applied 1 or 2 100% PWM cycles in forward and reverse directions for all phases (also 6 steps, same length pulses, 30..40Amps was needed for reliable detection, but had to wait for the decay of the current after each step) t...
by thorlancaster328
Feb 23 2021 1:50am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

It would be nice if we could remodel this to not require the phase controlled pwm, because then it would be applicable to the stm32 controllers used in... Most things. Unfortunately the lowest cost IC I can find that has arbitrarily-aligned PWM is the IMRXT1060 in the Teensy 4.0. If silent saliency...
by thorlancaster328
Feb 22 2021 11:06am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

Is a shortcut on this to inject the tone at the Va Vb stage of the FOC? Could you then read back the current changes from the ia and ib? Struggling to visualize this. That's sort of what I'm doing with the pilot tone. The voltage (duty cycle) varies a bit with each PWM cycle, in a 6-step pattern. T...
by thorlancaster328
Feb 22 2021 2:39am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

The paper had quite a bit of math in it that I didn't fully understand. However, I understood enough of it to implement an improved sensorless FOC algorithm that could reliably determine the motor's position, including the leading 180 degrees, from standstill. Instead of varying the PWM amplitude ov...
by thorlancaster328
Feb 22 2021 1:48am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

Managed to get SVPWM and saliency-based position detection working after a weekend of programming. Now I see why every motor controller doesn't have saliency-based sensorless starts. Not only does the inductance-detecting tone produce a whine, it is computationally intensive as well. CPU usage is no...
by thorlancaster328
Feb 22 2021 1:29am
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

What I saw before in my circuit was a wiggle symmetrical to the ground plane. The gate signal rose above, dipped below, and then levelled off. I've never seen a noise artifact get better with higher currents... Since your signal is (1) entirely positive, (2) has a fast rise time and slow decay time,...
by thorlancaster328
Feb 20 2021 1:54pm
Forum: Motor Technology
Topic: Another attempt at building a motor controller
Replies: 92
Views: 2248

Re: Another attempt at building a motor controller

I use a scope similar to this one: https://www.valuetronics.com/product/tds3012b-tektronix-digital-oscilloscope-used. I don't own it, University does, but I'll have access to it for another 3 semesters. It has about 10x the bandwidth necessary for measuring the ringing of my TO-247 parts and is prob...
by thorlancaster328
Feb 20 2021 3:13am
Forum: Vendor Relations Corner
Topic: Vector Ebikes taking >2 weeks to ship - Anyone else with this experience?
Replies: 4
Views: 246

Vector Ebikes taking >2 weeks to ship - Anyone else with this experience?

2 weeks ago, I ordered a typhoon frame and a motor from Vector Electric bikes. The day after payment went through, I asked them when they were planning to ship. Their response: Of course, as soon as we received your payment, we will start packing your order and will send you tracking number. A week ...