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Direct torque control (DTC) is one method used in variable-frequency drives to control the torque (and thus finally the speed) of three-phase AC electric motors. This involves calculating an estimate of the motor's magnetic flux and torque based on the measured voltage and current of the motor.
An ideal capacitor has no characteristics other than capacitance, but there are no physical ideal capacitors. All real capacitors have a little inductance, a little resistance, and some defects causing inefficiency. These can be seen as inductance or resistance in series with the ideal capacitor or in parallel with it. And so likewise with ...
The linear term in jω in this transfer function can be derived by the following method, which is an application of the open-circuit time constant method to this example. Set the signal source to zero. Select capacitor C 2, replace it by a test voltage V X, and replace C 1 by an open circuit.
Digitally tuned capacitor, a type of electrical capacitor whose capacitance can be changed by means of a digital control signal; Direct Torque Control, a method to control electric motors with very good torque dynamics; Direct traffic control, a method of authorizing track occupancy on American railroads
A multimeter in a resistance range can detect a short-circuited capacitor (very low resistance) or one with very high leakage (high resistance, but lower than it should be; an ideal capacitor has infinite DC resistance). A crude idea of the capacitance can be derived with an analog multimeter in a high resistance range by observing the needle ...
The maximum energy is a function of dielectric volume, permittivity, and dielectric strength. Changing the plate area and the separation between the plates while maintaining the same volume causes no change of the maximum amount of energy that the capacitor can store, so long as the distance between plates remains much smaller than both the ...
It is the time required to charge the capacitor, through the resistor, from an initial charge voltage of zero to approximately 63.2% of the value of an applied DC voltage, or to discharge the capacitor through the same resistor to approximately 36.8% of its initial charge voltage.
Capacitors used for suppressing undesirable frequencies are sometimes called filter capacitors. They are common in electrical and electronic equipment, and cover a number of applications, such as: Glitch removal on direct current (DC) power rails; Radio frequency interference (RFI) removal for signal or power lines entering or leaving equipment