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US 4,378,517 AGranted
Method and apparatus for controlling the energization of an electric motor
AssigneeCableform Limited
InventorsJohn Morton, John Jones
Life of this patent
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AssigneeCableform Limited
InventorsJohn Morton, John Jones
Estimating the term…
To control the energization of an electric motor pulses of current are supplied to the motor from a power source, and the pulse mark/space ratio and the motor field strength are controlled to determine the output speed and torque of the motor. Means are provided for deriving information representative of the speed of the motor and the torque required to be developed by the motor at that speed, and means are provided for determining information representative of the pulse mark/space ratio and the motor field strength necessary to provide the required torque at the said derived speed such that power losses are minimized. This makes it possible to control the motor field strength and mark/space ratio in accordance with the determined information to achieve optimum efficiency.
A method for controlling the energisation of an electric motor, wherein pulses of current are supplied to the motor from a power source, and both the mark/space ratio of the pulses and the motor field strength are controlled to determine the output speed and torque of the motor, comprising the steps of:
An apparatus for controlling the energisation of an electric motor, including means for supplying pulses of current to the motor from a power source, and means for controlling both the pulse mark/space ratio and the motor field strength to determine the output speed and torque of the motor, comprising:
Dependencies are inferred from the claim text.