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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 ...
Systems using VFDs can be more efficient than hydraulic systems, such as in systems with pumps and damper control for fans. [ 7 ] Since the 1980s, power electronics technology has reduced VFD cost and size and has improved performance through advances in semiconductor switching devices, drive topologies, simulation and control techniques, and ...
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.
A permanent magnet synchronous motor and reluctance motor requires a control system for operating (VFD or servo drive). There is a large number of control methods for synchronous machines, selected depending on the construction of the electric motor and the scope. Control methods can be divided into: [21] [22] Scalar control. V/f control ...
A VFD operates on the principle of cathodoluminescence, roughly similar to a cathode-ray tube, but operating at much lower voltages. Each tube in a VFD has a phosphor-coated carbon anode that is bombarded by electrons emitted from the cathode filament. [1] [2] In fact, each tube in a VFD is a triode vacuum tube because it also has a mesh ...
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 ...
A pure feed-forward system is different from a homeostatic control system, which has the function of keeping the body's internal environment 'steady' or in a 'prolonged steady state of readiness.' A homeostatic control system relies mainly on feedback (especially negative), in addition to the feedforward elements of the system.
Speed can be controlled in a number of ways, with the most popular type of variable speed drive (VSD) being the variable frequency drive (VFD). And mechanical methods are included in the original diagram which you've cropped out to make it seem to fit here. DMahalko 23:20, 13 March 2012 (UTC)w Were are all trying to solve a problem.