Construction and Applications of Brushless Motors
2025.06.02
table of contents
Contents of Episode 2:
- • What is a Motor?
- • Principle of Motor Rotation
- • What is a Brushless Motor?
- • The Number of Poles and Number of Slots in a Motor
- • Mechanical Angle and Electrical Angle of a Motor
- • IC Hall Elements (Hall ICs) in Brushless Motors
- • Construction of Brushless Motors
- • Applications of Brushless Motors
Construction of Brushless Motors
Brushless motors have any one of three different constructions—an inner rotor (or inrunner) design, an outer rotor (or outrunner) design, and a pancake (or axial flux) design. The constituent components and applications of each type of motor are shown below.
Inner rotor type brushless motors
In this construction, the rotor is inside the stator.
Outer rotor type brushless motors
In this construction, the rotor is outside the stator.
Pancake type brushless motors
In this construction, a fan-like part and the rotor are combined.
Applications of Brushless Motors
There are many different applications for brushless motors. One application that may be familiar to you is in the outdoor units of air conditioners. The motor driving circuit may be located either in the main unit or within the motor itself.
I have explained the basics of motors in Episodes 1 and 2. For more information, please refer to “Learn Devices” in Tech Web: Motor.
In the next episode, I will be discussing methods for driving brushless motors and motor characteristics.
Key points of this article
・There are many applications that use brushless motors. One that you may be familiar with is the outdoor units of air conditioners.
・The brushless motor driving circuit may be located in the main unit, or may be inside the motor.
Teacher Sugiken’s Motor Library
Teacher Sugiken’s Motor Driver Dojo
- [Episode 1] I Can See Them! Motor Fairies
- [Episode 2] Sugiken appears! The first step to becoming a super engineer
- [Episode 3] All of Sudden, a Rival Appears for Ichinose Manabu!?
- [Episode 4] A Sudden Closeness?! New Things the Two Have in Common
- [Episode 5] Passion! Which Thoughts Did Ichinose Sense from Ninomiya?
- [Episode 6] Test showdown! A serious battle between Ichinose and Ninomiya!
- [Episode 7] This Is Just the Beginning! Ichinose and Friends’ Motor Driver Dojo
- [Episode 8] The First Meeting! Lessons Learned in a Real Setting
- [Episode 9] A Shortcut to Becoming a Super Engineer!? Learning from the User’s Perspective
- [Episode 10] Beyond the Questions! What Engineer Ichinose Learns
- [Episode 11] Learning And Growing: It’s Not Just About Turning the Motor!
- [Episode 12] To the Next Stage! The Door To Becoming a Super Engineer Opens
An Introduction to Motors
Brushless Mortor Driver
Motor Q&A