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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 ...
Adjusting the brightness of light emitted by a light source is then merely a matter of setting at what voltage (or phase) in the AC half-cycle the dimmer begins to provide electric current to the light source (e.g. by using an electronic switch such as a triac). In this case the PWM duty cycle is the ratio of the conduction time to the duration ...
To improve their efficiency, high-power inverters (from about 10 kW) frequently make use of a technique referred to as a three-level design (three-level inverter). [3] Forming the basis of the S3L inverter is a hard-switching three-level inverter of this kind with a T-type topology. [4] This base design is supplemented by a snubber circuit ...
Mariusz Malinowski received the Ph.D. degree with honors in Electrical Engineering from the Warsaw University of Technology (WUT) in 2001 for his thesis entitled "Sensorless control strategies for three-phase PWM rectifiers" [1] [2].
An American Rotary Phase Converter with a Transformer. A phase converter is a device that converts electric power provided as single phase to multiple phase or vice versa. The majority of phase converters are used to produce three-phase electric power from a single-phase source, thus allowing the operation of three-phase equipment at a site that only has single-phase electrical service.
The half bridge is used in some switched-mode power supplies that use synchronous rectifiers and in switching amplifiers. The half-H bridge type is commonly abbreviated to "Half-H" to distinguish it from full ("Full-H") H-bridges. Another common variation, adding a third 'leg' to the bridge, creates a three-phase inverter.
Fig. 2: Top and bottom views of an air-cooled 10kW-Vienna Rectifier (400kHz PWM). The Vienna Rectifier is useful wherever six-switch converters are used for achieving sinusoidal mains current and controlled output voltage, when no energy feedback from the load into the mains is available.
Space vector modulation (SVM) is an algorithm for the control of pulse-width modulation (PWM), invented by Gerhard Pfaff, Alois Weschta, and Albert Wick in 1982. [1] [2] It is used for the creation of alternating current (AC) waveforms; most commonly to drive 3 phase AC powered motors at varying speeds from DC using multiple class-D amplifiers.