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Dynamic braking load analyzer

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TLDR
In this article, a dynamic braking load analyzer that determines the proper resistance value for a braking load resistor to be used in combination with a variable frequency drive or servo-drive to accommodate the power dissipated from an induction motor when it is being reduced in speed is presented.
Abstract
A dynamic braking load analyzer that determines the proper resistance value for a dynamic braking load resistor to be used in combination with a variable frequency drive or servo-drive to accommodate the power dissipated from an induction motor when it is being reduced in speed. The analyzer includes a resistor bank having a plurality of resistors electrically coupled in parallel. Switches are provided between the resistors, and a resistor selector switch determines which resistors are switched into the resistor bank circuit. A heat sensing resistor in the resistor bank measures the heat generated by the resistors and provides a signal that is read by a heat meter. The combination of the temperature measurement and the resistance of the resistors in the circuit gives the proper braking resistance value for the deceleration of the induction motor.

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References
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Dynamic brake blending for an inverter propulsion system

TL;DR: In this article, the stator terminals of an adjustable speed a-c induction motor are connected to a source of d-c electric power by means of an inverter, and a system is provided for blending both dynamic and regenerative electrical braking of the motor whenever it decelerates.
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TL;DR: In this paper, a phase-change heat sink coupled to the switches absorbs heat from the switches during hard acceleration, and returns the heat to the cooler under more constant-speed conditions.
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