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Motors

Learn about motors, motor design, motor control, and testing!

The Basics

A ‘Learning Map’ for Motors

Introduction to this Notebook

Introduction to Motors, and their Applications

List of Recommended Software

List of Recommended Resources

Brushed DC Motors Selection + Control

Fundementals of DC Brushed Motors + Control

Brushed DC Motors—an Overview

  • Brushed Motor Physics Equation Derived, Torque Speed Curve, Etc
  • https://www.youtube.com/watch?v=CWulQ1ZSE3c
  • https://www.youtube.com/watch?v=pxtRlKs0pAg

Pulse-Width-Modulation + its Applications to Motor Control, the H-Bridge

Current (Torque) Control of a Brushed DC Motor

  • Start w/ a simple DC motor that can do current control (NO GATE DRIVE CHIP, just use an H-bridge controller and current sensor, modular)

Drive Control Bandwith Analysis

  • How do you know if your motor drive and system is “good enough” for your application

Designing Commercial-Off-the-Shelf Brushed Motor Systems (COTS) –> INTEGRATE THIS WITH BRUSHLESS COTS SYSTEMS AS WELL!!!

Like just “designing COTS motor systems”

Selecting a Brushed Motor for an Application

  • gear ratios, torque speed curves, etc

Selecting a Motor Controller for an Application + Interfacing With It

  • when should you NOT design a motor controller, when can you use something else for a motor controller

Encoders + Encoder Selection

Using Power Converters as Motor Controllers (The Prius Power Stage Case Study)

Power Analysis, Programming Power Curves (Go-Kart Throttle Response Case Study)

Building your Own Motor Controller

Design of Brushed Motor Controllers

  • general layout
  • fet selection
  • current sensing
  • power stage and protection
  • regenerative braking… etc etc
  • inputs / outputs

Sensing Precision, PWM Switching Frequency, and Effects on Control

  • Design of Brushed Motor Inverters (fet selection, current sensing, PWM clock speeds)
  • Regenerative Braking in Brushed Systems (without a gate drive chip)
  • Introduction to Gate Drive Chips + Why you might want to Use them

Brushless DC Motors Selection + Control

  • Brushless DC Motors overview, three-phase, PEAK POWER POINT AND SATURATION (T/S curves)
  • Simple forms of brushless motor control
  • Field-Oriented Control + Theory, torque control of three-phase motors (using a small BLDC and something like an O-Drive)
  • SVM (space-vector modulation)
  • Calibration routines, current sensing, encoders and state estimation for commutation
  • Designing an Inverter for three-phase brushless motor control w/ a Gate Drive chip
  • Designing an Inverter for three-phase brushless motor control with Discrete Gate Drivers + Current Sensing (circuitden.com/blog/11)
  • Regenerative Braking in Brushless Systems

Higher Level Forms of Control!

  • Speed Control, Position Control
  • Impedance Control! (fun applications)
  • Field Weakening Control for BLDC motors
  • Stat Machines in Motor Control + Triggering Switches

Power Generation

Motor Design + Testing

Introduction to Motor Design

  • Poles Slots
  • Brush wear for brushed systems
  • Bearing selection + design
  • Ansys Motor CAD
  • Dyno systems
  • efficiency maps, power maps

Check out: https://keysan.me/ee564/ (for motor design)

BORROW THINGS FROM 2.74 BUT RE-WRITE MOST OF IT!!!

WHY DO WE NOT NEED REGEN PROTECTION FOR A DYNO WITH TWO MOTORS??

HOW TO ESIMATE TORQUE SPEED CURVE FROM MAGNETIC SATURATION, PEAK POWER POINT, FREE SPEED b/c PPP =/ the Knee

DON’t RE-WRITE THINGS THAt DON’T NEED RE-WRITING THE SAME WAY WE DID THE PCB CLASS

We will see, but all tutorials might be in STMCubeIDE not MBED and we’ll explain why (optimization of code)

other resources

https://rlib.redarm.in/post/winding-pattern/

https://www.electrical4u.com/armature-winding-pole-pitch-coil-span-commutator-pitch/

maybe this too? https://www.tutorialspoint.com/pitch-factor-or-coil-span-factor-in-alternator#:~:text=The%20coil%20span%2Dfactor%20or,also%20known%20as%20chording%20factor.

great video: https://www.youtube.com/watch?v=rTsRSTzeqaM

also good: https://www.youtube.com/watch?v=Tq5O7ma-xno

http://www.davidsonsales.com/public/pdfs/CoilPitch.pdf