Skip to main content
Lkr.1
Associate II
May 5, 2021 12:36 PM UTC
Solved

Controller for dual encoder and 100kHz PWM brushless motor

Hi,

I"m starting new project with brushless motor and I would like to connect two encoders (Rotary and Linear) with 3 hall affects and current measurement.

I would like to check which ST controller "strong "enough for the application

following the parameters of the motor

  1. PWM to the phases shall be ~100kHZ
  2. Motor speed up to 10000RPM
  3. Rotary incremental encoder of 4096 pulse
  4. Incremental Linear encoder resolution ~5um

According to above parameters I need 2 inputs for Rotary encoder at ~700kHz, 2 addition inputs for linear encoder and 3 PWM outputs of 100kHz.

I need to close PID for speed and position loopback with very high resolution, and run SPI communication to the main controller at 10Mb/s.

I have strict restrictions of the pcb size and I have to choose smallest controller.

I have two questions:

  1. Can I use STSPIN32F0A controller with embedded Cortex-M0 MCU or it better to use STM32F4 controllers line? Does anyone run this component at dual encoder mode?
  2. How can I know which controller can support 4 encoder inputs (with counter for 700kHz encoder), 3 Halls and PWM of 100kHz?

Thanks

This topic has been closed for replies.
Cristiana SCARAMEL
ST Employee
May 6, 2021 8:56 AM UTC

Hi @Lkr.1​ and welcome to the ST Community.

I suggest you take a look at our new High performance 3-phase motor controller with embedded STM32G4 MCU: STSPIN32G4

In the 'Tools & Software' tab you can find the dedicated demonstration boards.

The firmware for the board based on Field Oriented Control algorithm can be generate with the software STM32 Motor Control SDK, X-CUBE-MCSDK version 5.Y.0 (or greater).

I hope this post can help you; if so, consider to mark it as best answer by clicking the label "Select as Best".

"If you feel a post has answered your question, please click ""Accept as Solution"""

4 replies

Javier1
Principal
May 5, 2021 12:45 PM UTC

>"I have to choose smallest controller"

smaller packaging i suppose you meant?

I would chose F4 because the last thing you want is run out of processing juice once the hardware has been designed.(you want to keep up with your PID rate and 10Krpm are a lot of rpm)

Maybe some bga packaging?

>How can I know which controller can support 4 encoder inputs (with counter for 700kHz encoder), 3 Halls and PWM of 100kHz?

You need timers for that,

one timer for pwm generation (probably advanced timer1)

The 700kHz encoder handling can be done in hardware with another timer working in input capture mode and some DMA action.

hit me up in https://www.linkedin.com/in/javiermuñoz/
Lkr.1
Lkr.1Author
Associate II
May 6, 2021 10:43 AM UTC

Thanks

I"l check STM32G4  with input capture mode.

Cristiana SCARAMEL
ST Employee
May 6, 2021 8:56 AM UTC

Hi @Lkr.1​ and welcome to the ST Community.

I suggest you take a look at our new High performance 3-phase motor controller with embedded STM32G4 MCU: STSPIN32G4

In the 'Tools & Software' tab you can find the dedicated demonstration boards.

The firmware for the board based on Field Oriented Control algorithm can be generate with the software STM32 Motor Control SDK, X-CUBE-MCSDK version 5.Y.0 (or greater).

I hope this post can help you; if so, consider to mark it as best answer by clicking the label "Select as Best".

"If you feel a post has answered your question, please click ""Accept as Solution"""
Lkr.1
Lkr.1Author
Associate II
May 6, 2021 9:42 AM UTC

Hi,

Thanks for the answer.

I would like to test the STSPIN32G4. I"ll order EVSPIN32G4 evaluation board and update it with my motors.