The document discusses the operation of AC motors and the concept of DC injection braking as a method to slow AC motors. It explains how an AC motor functions with a stationary stator and a rotating rotor, and highlights the dependency of rotor speed on AC frequency and motor pole count. The DC injection braking technique involves applying a DC voltage to the motor windings after disconnecting AC voltage to create braking force.

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KIMO Industrie-Elektronik GmbH
Intelligent Drive Solutions
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DC Injection Braking unit
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• how motor works
• DC Injection Braking unit
• Uses or non uses?
• Benefits of Braking units
Topics
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Working of AC Motor
AC Motors
Commonly consists of two basic parts, an outside
stationary stator having coils supplied with alternating current to
produce a rotating magnetic field, and an inside rotor attached to
the output shaft that is given a force to rotate (torque) by the
rotating field.
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The rotation is achieved by
constantly rotating magnetic
field.
From the picture A1-A2, B1-
B2 and C1-C2 are poles,
as and when the current
flow through this poles
alternatively, force is set on
the center conductor (rotor )
to rotate
Working of AC Motor
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In the above picture you can notice that alternating magnetic field is
achieved by AC current, and the speed of the rotor completely depends
on the number of cycles in AC current (also called as frequency) and
number of poles present in the motor. And the speed of the motor is
given by Srpm = (120 x F) / P; were F = frequency of the current and
P = no of poles in the motor.
Working of AC Motor
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DC Injection braking
DC injection braking is a method of slowing AC electric motors. A
DC voltage is injected into the winding of the AC motor after the
AC voltage is disconnected, providing braking force to the rotor.[1]
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Thank you for your attention!
Looking forward to your questions..
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KIMO Industrie-Elektronik GmbH
India: c/o Voyage Incorporation
67, Ground Fl., Sunkalpet Main
Road, Bengaluru – 560002
www.kimo.co.in
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Am Weichselgarten 19
D-91058 Erlangen
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