Patent
Method and circuit for clamping the recirculation current in stator windings
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TLDR
In this paper, a circuit for clamping the voltage spike of a stator coil winding of a brushless direct current motor is described, where a comparator is designed to trigger at a desired threshold voltage so that the threshold can optimized.Abstract:
A circuit for clamping the voltage spike of a stator coil winding of a brushless direct current motor is disclosed. The circuit uses a comparator to monitor the voltage on a stator winding. When a voltage spike is detected, the comparator turns on the stator winding driver transistor to clamp the voltage spike. The comparator can be designed to trigger at a desired threshold voltage so that the threshold can optimized. Additionally, the comparator can be selectively disabled to trigger when voltage spikes are anticipated.read more
Citations
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References
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Patent
Brushless DC motor
Toshio Inaji,Makoto Gotou +1 more
TL;DR: In this article, a brushless DC motor with zero-crossing points of counter electromotive forces induced in the stator windings of the rotor is detected to obtain a pulse signal train.
Patent
Control apparatus for brushless motor
TL;DR: In this paper, the polarity of a counter electromotive force generated in an armature coil of a brushless motor for a nonexcited phase due to the rotational oscillation of the rotor was calculated by combining the potential of a neutral point of the armature winding having the armatures coils connected in star-connection and that of a detecting resistance circuit having resistors connected in Star-connection.
Patent
Control system for brushless DC motor
TL;DR: In this article, the maximum value of an input DC current to a motor drive circuit is held and the phase of the rotor position detection signals is changed in accordance with the held value of the input dc current to prevent the phase detection signals from varying with the load on the brushless DC motor.
Patent
Method and apparatus for operating polyphase DC motors
TL;DR: In this paper, a polyphase dc motor with a plurality of "Y" connected stator coils has a back emf amplifier switchable connected to at least one floating coil in accordance with sequence signals received directly from a sequence generator.
Patent
Brushless direct current motor with minimized current ripple and method
TL;DR: In this paper, a brushless direct current motor with commutation current control was proposed to control the rate of turn-off of the phase being turned off while simultaneously controlling the speed of turn on of the current flowing in the phases being excited.