China
Africa
Explore chapters and articles related to this topic
Motor Frame Design
Published in Wei Tong, Mechanical Design and Manufacturing of Electric Motors, 2022
The fastener yield torque improvement due to cold working is demonstrated in Figure 5.41. During a tightening process, both the torque applied to the fastener and the angular displacement of the fastener increase simultaneously along the torque–angle curve. Tightening the fastener beyond the yield point but below the ultimate tensile strength can achieve the maximum preload for a given fastener size [5.30]. Due to the plastic deformation of the fastener, releasing the load will not return the fastener to its original state. Then, retightening the fastener again, it is found that the torque and angular displacement increase along the offset curve that is approximately parallel to the first torque–angle curve and the yield torque appears at a higher level (Ty2 > Ty1).
Modified LUT-based DTC of NPC 3-Level Inverter fed Sensorless IPMSM Drive with DC Link Voltage Balance
Published in IETE Technical Review, 2022
Toshi Sharma, Avik Bhattacharya
In general, electromagnetic torque in an AC drive can be given as follows: where is a constant; are the magnitudes of the stator and rotor flux linkages. The angle between them is the Torque Angle () and is shown in Figure 1. By altering, the torque of an AC machine can be regulated. In order to change the (), stator flux vector location in stationary reference frame is to be known. Furthermore, by applying suitable voltage vector in required direction and for certain duration, the instantaneous stator flux equation using can be written as [4] follows: Ignoring the resistive drop in stator winding, can be reframed as follows: or In order to choose appropriate switching vector to control the electromagnetic torque, a switching table is constructed, as shown in Table 1.