Interlocking Components in Electrical Drives: Sensing of signals required for speed and current control loops. Sequencing and interlocking operations are explained in the previous section, whereas this section discusses components used in interlocking and sequencing operations, and protection. It should be noted that signals for Interlocking Components in Electrical Drives and sequencing operations must be …
Electrical Drive Systems: Each Electrical Drive Systems is different from other Electrical Drive Systems. However, there are some common features associated with all Electrical Drive Systems. To understand them it is good enough to consider few examples. This approach has been adapted here. Normally, a Electrical Drive Systems receives its incoming ac supply from a …
Measures for Energy Conservation in Electrical Drives: Following Measures for Energy Conservation in Electrical Drives: Use of efficient semiconductor converters. Use of efficient motors. Use of variable speed drives. Energy efficient operation of drives. Improvement of power factor. Using a motor of right rating. Improvement of quality of supply. Use of single- to three-phase semiconductor …
Measures for Energy Conservation in Electrical Drives Read More »
Energy Losses in Electrical Drive System: Energy conservation in electrical drive is achieved by reduction of losses in its various parts. Typical Energy Losses in Electrical Drive System include the following: 1. Electrical transmission losses: These losses depend on the drive power factor and harmonics in the line current. 2. Conversion losses in the power …
Classes of Motor Duty in Electrical Drives: IS: 4722-1968 categorises various load time variations encountered in practice into eight standard Classes of Motor Duty in Electrical Drives: Continuous duty. Short time duty. Intermittent periodic duty. Intermittent periodic duty with starting. Intermittent periodic duty with starting and braking. Continuous duty with intermittent periodic loading. Continuous duty …
Heating and Cooling Curves of Electrical Drives: An accurate prediction of Heating and Cooling Curves of Electrical Drives rise inside an electrical motor is very difficult owing to complex geometrical shapes and use of heterogeneous materials. Since conductivities of various materials do not differ by a large amount, a simple thermal model of the machine …
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 …
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 …
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 …
Dynamics of Electrical Drives: 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 independent of the speed (Fig. 2.3). At low speeds, windage torque is negligible. Therefore, net …