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Thank goodness for Brushless DC Motors!!

Thank goodness for Brushless DC Motors!!

When I was a student I had an old Ford Granada which for some time I thought had a battery that would not hold charge. Cutting back on the beer for some months (fortunately in Yorkshire I could always park at the top of a hill and bump start it) I saved enough to buy a new battery. The guy at the garage was honest and as he disappeared in a cloud of smoke from his battery tester, he educated me by saying the problem lay in the brushes of the starter motor. On my long journey through Life I’ve also owned a hammer drill that under load threw off enough sparks from the brushes it looked more like an Arc welder, and a washing machine that needed a tilt and drop between each part of its cycle to get my washing done. Both were suffering brush problems.

While brushless motors need a controller, they are commutated electronically with fixed induction coils and  mobile magnets, unlike bushed motors which are mechanically commutated with moving coils and produce variable torque which decreases with speed.

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There are many benefits using brushless motors, including superior control of speed and torque, elimination of brush generated electromagnetic interference, which is caused by brushes arcing in brush motors, higher efficiency with lower power losses, higher power density which reduces size for equivalent power brushless motors. Brushless motors can also operate at higher speeds with lower noise.

 

The fixed induction coils can also be more easily cooled leading to longer motor life, and lower rotor inertia, which (in combination with sensors & microcontrollers) offers greater control and positioning accuracy for Industrial and IoT control applications. The electronic control provided by products like Infineon’s half bridge motor drives (i.e. BTN8982TA - RS stk no 906-3085 and its Arduino Shield format Eval board RS stk no 906-2874), simplify and add robustness to system design.
Here's a typical Application Approach from Infineon.

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In addition for battery powered equipment like cordless drills, screwdrivers, vacuum cleaners, etc
RS has just introduced the Infineon StrongIRFet devices, which can also be used on switched mode power supply secondary side applications.

IRF60B217 -60V 60A T0220AB   RS Stock No 1236144
IRF60R217 -60V 58A DPAK         RS Stock No 1236145
IRL60S216 -60V 298A D2PAK     RS Stock No 1236146
IRL60SL216-60V 298A T0262     RS Stock No 1236147

 

As part of an upcoming BLDC feature at RS we also have some BLDC motor control kits you may be interested in.

300W_MOTORCONTROL_SS08 - RS Stock No 910-6867
Motor Control Application Kit for XMC1300 - RS Stock No 910-6854

 

Product Group Manager - Semiconductors

Comments

0 Votes
TRADINWOLRD

November 22, 2016 13:22

can you give me your email M Adrain Gurr

0 Votes
Adrian Gurr

September 5, 2016 11:05

My thanks to philtilson for correctly pointing out the errors, standards are important.
I guess that will teach me not to do these so late in the evening.
Hopefully after a few quick edits, everyone will get more from the article.

0 Votes
PhilTilson

September 5, 2016 09:49

Interesting article, but the author really needs to get someone to proof-read his copy before publication!

"Both we suffering brush problems"; "...and a mobile magnets"; "...unlike bush motors"; "...Infineon’s half bridge motors drives"; "...lower rota inertia".

This may seem like nit-picking, but in a professional article, these errors detract from the content.