Control of Electrical Drives

Control of Electrical Drives:

Closed Loop Speed Control of Multi Motor Drives : When mechanical part of the load is of large physical dimension it becomes desirable to share the load between several motors. For example a rotary printing press usually has several printing stations which are mechanically coupled by a long drive shaft. Control of Electrical Drives …


Closed Loop Torque Control of Drives : Closed Loop Torque Control of Drives scheme of Fig. 3.4 finds application in battery operated vehicles, rail cars and electric trains. Driver presses the accelerator to set torque reference T. Through Closed Loop Torque Control of Electrical Drives, the actual motor torque T follows torque reference T. Speed feedback loop is present through the driver. By …


Current Limit Control of Drives : Current Limit Control of Electrical Drives scheme of Fig. 3.3 is employed to limit the converter and motor current below a safe limit during transient operations. It has a current feedback loop with a threshold logic circuit. As long as the current is within a set maximum value, feedback loop does not affect operation of the drive. During …


Current Sensing of Electrical Drives : Current Sensing of Electrical Drives is required for the implementation of current limit control, inner current control loop of closed-loop speed control, closed-loop torque control of a dc drive, for sensing fault conditions, and for sensing speed in dc drives by back emf sensing method. In order to avoid interaction between control circuit, carrying low voltage …


Modes of Operation of Electrical Drive : Three types of Modes of Operation of Electrical Drive: Steady-State Acceleration including starting Deceleration including stopping As we know already, steady-state operation takes place when motor torque equals the load torque. The steady-state operation for a given speed is realized by the adjustment of steady-state motor speed-torque curve such that the motor and load torques are equal at this …


Phase Locked Loop Control : A PI controller ideally should provide perfect speed regulation. However, due to imperfections in sensing and control circuits, the closed-loop schemes described earlier can at best achieve a speed regulatio of 0.2%. The Phase Locked Loop Control (PLL) can achieve a speed regulation as low as 0.002% which can be useful in conveyers for material handling, paper …


Speed Control and Drive Classification : Speed Control of Electrical Drives and Drive Classification are the Drivers where the driving motor runs at a nearly fixed speed are known as Constant Speed or Single Speed Drives. Multi-speed drives are those which operate at discrete speed settings. Drives needing stepless change in speed and multispeed drives are called Variable Speed Drives. When a number of motors …


Updated: April 29, 2020 — 11:01 pm