preview

Essay On Speed Control

Decent Essays
The variable speed control of electric drives benefited his last year’s significant methodological and technological advances. Indeed digital electronics projects and development of components of the power electronics allows it today to implement control algorithms possible there about ten years. In various modern industrial applications, the induction machine has a special attention mainly due to its reliability, robustness; it’s relatively low cost and eases of construction and maintenance[1]. The improvement of the quality of the energy on the electrical distribution networks becomes today an important stake for the managers of the networks as for the operators of the electrical energy. In normal operation, the quality of the…show more content…
They are distinguished by their structure and their control strategy in order to constrain the shape of the wave of the absorbed currents. They can be divided into three classes: single phase diode rectifier followed by a PFC (Power Factor Correction), rectifier with current injection (composed of a three-phase diode rectifier equipped with a modulation circuit and d A distribution circuit for the injection of currents required in the network), and the Boost PWM Rectifier using a voltage inverter bridge[5][6] [7]. Over the years, variant strategies have been proposed in the literature for the control of the three-phase voltage (AFE) rectifier. All these strategies aim to achieve the same objectives, namely: a high power factor (close to one) and a quasi-sinusoidal waveform of the currents absorbed. They are differentiated by the nature of the servo loop used. The latter may be either current or power. For this purpose, two classes can be distinguished: VOC (Voltage Oriented Control): using a current loop, developed by analogy with the vector control of electrical machines. It consists in orienting the current vector in the same direction as that of the voltage vector [8], DPC (Direct Power Control): developed by analogy with the direct torque control (DTC) of induction motors. It is to control the instantaneous power, active and reactive, instead of the torque and flux through two inner loops [9]. In the reference [10],
Get Access