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In vector control, an AC induction or synchronous motor is controlled under all operating conditions like a separately excited DC motor. [21] That is, the AC motor behaves like a DC motor in which the field flux linkage and armature flux linkage created by the respective field and armature (or torque component) currents are orthogonally aligned such that, when torque is controlled, the field ...
Thus it is not possible to control the motor if the output frequency of the variable frequency drive is zero. However, by careful design of the control system it is possible to have the minimum frequency in the range 0.5 Hz to 1 Hz that is enough to make possible to start an induction motor with full torque from a standstill situation. A ...
The scalar control has been to a large degree replaced in high-performance motors by vector control that enables better handling of the transient processes. [1] Low cost and simplicity keeps the scalar control in the majority of low-performance motors, despite inferiority of its dynamic performance; [ 3 ] vector control is expected to become ...
Small variable-frequency drive Chassis of above VFD (cover removed). A variable-frequency drive (VFD, or adjustable-frequency drive, adjustable-speed drive, variable-speed drive, AC drive, micro drive, inverter drive, variable voltage variable frequency drive, or drive) is a type of AC motor drive (system incorporating a motor) that controls speed and torque by varying the frequency of the ...
A vacuum fluorescent display (VFD) is a display device once commonly used on consumer electronics equipment such as video cassette recorders, car radios, and microwave ovens. A VFD operates on the principle of cathodoluminescence , roughly similar to a cathode-ray tube , but operating at much lower voltages.
V/Hz control is also sometimes referred to as scalar control or variable voltage, variable frequency (VVVF) control. Higher performance load applications are increasingly been been used for AC drives with multi-level and cellular inverter topologies and closed loop and sensorless vector or DTC control. [3].
The recording media in a video floppy is a flexible magnetic disk 47 mm (1.9 in) in diameter and 40 μm (0.0016 in) thick. [4] The disk is housed in a rectangular cartridge with one chamfered corner for orientation, measuring 60 mm × 54 mm × 3.6 mm (2.36 in × 2.13 in × 0.14 in); the cartridge is equipped with a sliding shutter for dust protection and a hub opening that is 15.9 mm (0.63 in ...
Space vector modulation is a PWM control algorithm for multi-phase AC generation, in which the reference signal is sampled regularly; after each sample, non-zero active switching vectors adjacent to the reference vector and one or more of the zero switching vectors are selected for the appropriate fraction of the sampling period in order to ...