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Armature control is the most common control technique for DC motors. In order to implement this control, the stator flux must be kept constant. To achieve this, either the stator voltage is kept constant or the stator coils are replaced by a permanent magnet. In the latter case, the motor is said to be a permanent magnet DC motor and is driven ...
A DC motor is an electrical motor that uses direct current (DC) to produce mechanical force. The most common types rely on magnetic forces produced by currents in the coils. Nearly all types of DC motors have some internal mechanism, either electromechanical or electronic, to periodically change the direction of current in part of the motor.
A Ward Leonard Control system with generator and motor connected directly. The speed of a DC motor is controlled by varying the voltage fed to the generator field windings, V gf, which varies the output voltage of the generator. The varied output voltage will change the voltage of the motor, since they are connected directly through the armature.
In the armature, an electromotive force is created by the relative motion of the armature and the field. When the machine or motor is used as a motor, this EMF opposes the armature current, and the armature converts electrical power to mechanical power in the form of torque, and transfers it via the shaft. When the machine is used as a ...
A DC motor's speed and torque characteristics vary according to three different magnetization sources, separately excited field, self-excited field or permanent-field, which are used selectively to control the motor over the mechanical load's range. Self-excited field motors can be series, shunt, or a compound wound connected to the armature.
In the subject area of control theory, an internal model is a process that simulates the response of the system in order to estimate the outcome of a system disturbance. The internal model principle was first articulated in 1976 by B. A. Francis and W. M. Wonham [1] as an explicit formulation of the Conant and Ashby good regulator theorem. [2]
SOURCE: Integrated Postsecondary Education Data System, University of Massachusetts-Lowell (2014, 2013, 2012, 2011, 2010). Read our methodology here. HuffPost and The Chronicle examined 201 public D-I schools from 2010-2014. Schools are ranked based on the percentage of their athletic budget that comes from subsidies.
The rotary converter can be thought of as a motor-generator, where the two machines share a single rotating armature and set of field coils. The basic construction of the rotary converter consists of a DC generator (dynamo) with a set of slip rings tapped into its rotor windings at evenly spaced intervals. When a dynamo is spun the electric ...