From my medical equipment repair days, I have come across resolvers that the reference coil is on the stator and the readout is done on the rotor ( they can definitely afford the space there ). Nice stuff indeed, not many people know of them nowadays ( most motor control will actually be done with encoders with an index pulse given from somewhere in the system ).
Oh cool, so that actually exists then. At least in vehicles and with synchronous motors I have only seen absolute feedback such as resolvers or sin/cos hall chips.
This was an awesome video. Could this be used to convert resolver inputs to encoder ABZ outputs? Im thinking of using a stm32 blue pill and some external circuit to do this.
Thanks for the video.Let mi suggest a topic : An electrical axis. An master encoder, a slave encoder and an output that control a motor+slave encoder that follow to master encoder in velocity and phase with a low margin de error (< 5 degrees so and so). Thanks Johannes
If we set 7 volts in the primary coil, what will be the peak voltage in the cosine coil at angle zero Is it 7 volts or less? The rule to find out the peak voltage at angle zero is as follows (peak potential of the cosine signal = voltage on the input coil x cosine of angle sita) (V cosine=Vr x cos cita)
Johannes, could you please share winding schemes of resolver, and drawings or sizes of stator and rotor ? as I remember rhis type of resolver (with this type of rotor) named Verner ?
The exact combination has not been tested, but yes the board can handle resolver and the software can handle PMSM. Both tested with Nissan Leaf hardware
@@EngineersFear Cool, I'm now in the middle ow hard desigion what to buy for prius gen 2 inverter. Another last one question: are two boards capable of handling two inverters(inside prius inverter case) in parallel to drive two similar motors(tesla-like 4WD) or one board can handle two inverters at the same time? Thank you!
@@EngineersFear I've already came to same conclusion because the board needs to get a feedback from a motor. And feedback from two motors will be different. Thank you!
@@EngineersFear Thanks, I'll go with that to start with, mine appears to be 4 pairs by that reasoning too. openinverter.org/wiki/images/d/d1/20201124_214308.jpg
Superb video. Thanks for the in depth walk through!! Looking for more in this series. Btw, just a basic question: why are there many coils when there are 2 output signals and 1 input? Are they connected on parallel?
According to my understanding they are connected in series. The one in the middle is the Tx and the right one next e.g.the sine coil and the one left to the Tx is the cosine Winding. However, a 4 pole pair should have 12 cool systems instead of 10 :/
Thank you for this excellent and informative video, Johannes. Please would you consider expanding the code to handle synchro resolvers which have three secondary windings connected in a Y configuration? Otherwise, it is necessary to convert the 3 phase synchro signal to a 2 phase resolver using a Scott-T transformer (difficult) or equivalent solid state converter. Thank you again 👍
You're welcome. It's targeted to EV motors and those don't seem to use synchro resolvers. Sounds like you need something like a Clarke/Park transform for that. It's open source, give it a shot ;)
Functional safety involves correct component selection, electronics/system design, as well as software development. Safety doesn't seem to be covered in any of your videos or inverter designs, which is worrying because an incorrect torque could cause a serious accident.
Good idea sir, please continue this series with explaining how the code and hardware works.
Thanks for the video. Great idea for this series. Gives us a better understanding of what's going on.
From my medical equipment repair days, I have come across resolvers that the reference coil is on the stator and the readout is done on the rotor ( they can definitely afford the space there ). Nice stuff indeed, not many people know of them nowadays ( most motor control will actually be done with encoders with an index pulse given from somewhere in the system ).
Oh cool, so that actually exists then.
At least in vehicles and with synchronous motors I have only seen absolute feedback such as resolvers or sin/cos hall chips.
Great explanation Johannes. Please keep going to make videos just like this:)
Very nice video Johan, just keep 'em coming (from one of the nerds)
Would like to know about F o C control of pmsm motors
here you go: ua-cam.com/video/7_UDy5PJA8w/v-deo.html
This is some wicked smart shit! I don't understand any of it, but respect those that do, ha ha
I hated working with Resolver that encoder ,this video changes my attitude
Great 🙂
Great video, gives a lot of useful information! Keep them coming :)
Literally exciting topic :)
Thank you so mutch for these videos.
This was an awesome video. Could this be used to convert resolver inputs to encoder ABZ outputs? Im thinking of using a stm32 blue pill and some external circuit to do this.
Probably, yes. AB can be generated with a timer in variable frequency mode and Z by toggling a pin on zero crossings
Thanks for the video.Let mi suggest a topic : An electrical axis.
An master encoder, a slave encoder and an output that control a motor+slave encoder
that follow to master encoder in velocity and phase with a low margin de error (< 5 degrees so and so).
Thanks Johannes
This was an awesome video
If we set 7 volts in the primary coil, what will be the peak voltage in the cosine coil at angle zero Is it 7 volts or less? The rule to find out the peak voltage at angle zero is as follows (peak potential of the cosine signal = voltage on the input coil x cosine of angle sita) (V cosine=Vr x cos cita)
I really liked this. When the leaf inverter chip is released could you make a tutorial for that as well?
Thanks! Yes I can make an installation video
Can i conect a synchro of 400 hz to 60 hz????
Johannes, could you please share winding schemes of resolver, and drawings or sizes of stator and rotor ? as I remember rhis type of resolver (with this type of rotor) named Verner ?
Will see what I can do, got one resolver left over
This is really good! Thanks!
Super stuff Johannes
Great learing module sir thank you...
Hello! Is this board "Main board V3" capable of handling prius gen 2 inverter coupled with any toyota PMSM motor with resolver? Thank you!
The exact combination has not been tested, but yes the board can handle resolver and the software can handle PMSM. Both tested with Nissan Leaf hardware
@@EngineersFear Cool, I'm now in the middle ow hard desigion what to buy for prius gen 2 inverter.
Another last one question: are two boards capable of handling two inverters(inside prius inverter case) in parallel to drive two similar motors(tesla-like 4WD) or one board can handle two inverters at the same time? Thank you!
@@konstantin88181 Yes you'd need two controller boards
@@EngineersFear I've already came to same conclusion because the board needs to get a feedback from a motor. And feedback from two motors will be different. Thank you!
Is there a way to determine the resolver pole pairs count?
In the picture you see that the core has 4 lobes = 4 pole pairs.
But I haven't seen enough different resolvers to be sure it's always that easy.
@@EngineersFear Thanks, I'll go with that to start with, mine appears to be 4 pairs by that reasoning too. openinverter.org/wiki/images/d/d1/20201124_214308.jpg
Superb video. Thanks for the in depth walk through!! Looking for more in this series. Btw, just a basic question: why are there many coils when there are 2 output signals and 1 input? Are they connected on parallel?
To be honest, I have no idea. It is 4 pole pairs (1 physical turn yields 4 electrical), thats probably got something to do with it
According to my understanding they are connected in series. The one in the middle is the Tx and the right one next e.g.the sine coil and the one left to the Tx is the cosine Winding. However, a 4 pole pair should have 12 cool systems instead of 10 :/
Thank you for this excellent and informative video, Johannes.
Please would you consider expanding the code to handle synchro resolvers which have three secondary windings connected in a Y configuration?
Otherwise, it is necessary to convert the 3 phase synchro signal to a 2 phase resolver using a Scott-T transformer (difficult) or equivalent solid state converter.
Thank you again 👍
You're welcome. It's targeted to EV motors and those don't seem to use synchro resolvers. Sounds like you need something like a Clarke/Park transform for that. It's open source, give it a shot ;)
what is the library that you are using for stm programming ? Thank you.
Hi, Thanks for the video. I will be trying to replicate this resolver on TI MCU.
I see no mention of functional safety. Have you at least tried to meet any safety standards, and if so, which ones and how?
Well I do check for minimal amplitude. Otherwise I suggest you check the recent code on github
Functional safety involves correct component selection, electronics/system design, as well as software development. Safety doesn't seem to be covered in any of your videos or inverter designs, which is worrying because an incorrect torque could cause a serious accident.
The fan noise in your office is quite intrusive. A lapel mic should avoid this.
Yeah sorry about that, it was a digging machine
Sorry, I meant when you were showing the sourcecode, it sounded like the computer's CPU fan.
Oh ok, yes that's possible. Will take care of it
Indeed, when I was editing the video the fan was going so I didn't realize it was on the recording also