Current Limit Control of Drives: Current Limit Control of 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…
Speed Control and Drive Classification: Speed Control 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…
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 Equalisation in Electrical Drives: Load Equalisation in Electrical Drives - In some drive applications, load torque fluctuates widely within short intervals of time. For example, in pressing machines a large torque of short duration…
Steady State Stability of Drive: Equilibrium speed of a motor-load system is obtained when motor torque equals the load torque. Drive will operate in steady-state at this speed, provided it is the speed of stable…
Time and Energy Loss in Transient Operations: Starting, braking, speed change and speed reversal are transient operations. Time and Energy Loss in Transient Operations can be evaluated by solving Eq. (2.19) along with motor circuit…
Classification of Load Torques: As we know already, the nature of Classification of Load Torques depends on particular application. A low speed hoist is an example of a load where the torque is constant and…
Components of Load Torques: Components of Load Torques Tl can be further divided into following components: (i) Friction torque TF : Friction will be present at the motor shaft and also in various parts of the load.…
Motor Design Parameters: Different parts of a load may be coupled through different mechanisms, such as gears, V-belts and crankshaft. These parts may have different speeds and different types of Motions such as rotational and…
Four Quadrant Operation of Motor Drive: For consideration of Four Quadrant Operation of Motor Drive, it is useful to establish suitable conventions about the signs of torque and speed. Motor speed is considered positive when…
