Patent
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.read more
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Patent
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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