Electric Motor Torque Speed Curve

The motoring region of the induction machine torque speed curve is the region of greatest interest.

Electric motor torque speed curve.

The plots below show a number of different torque speed curves due to differences in the motor designs. Torque speed curve the torque developed by a conventional 3 phase motor depends on its speed but the relation between the two cannot be represented by a simple equation. The x axis is motor speed from 0 to 120 hertz. Normally at it s top at operating speed.

Zero at 0 speed and. The power produced by the motor depends on the speed of the motor and is. Like pumps motors produce a torque speed curve of their own. Figure 7 shows the torque speed characteristic as it might actually appear.

When the speed of an ac motor is controlled by a vfd hp or torque will change depending on the change in frequency. The starting torque is indicated on the torque speed curve shown above. The torque speed curves shown below are actual curves for the green maxon motor pictured at right used by students in 2 007. In this overlay the shaded area reflects the.

Motor torque speed curve is a very good approximation. The power is just peaking at around 6000rpm. In this diagram t represents the nominal full load torque of the motor. As the motor picks up speed torque decreases slightly to the lowest point shown on the curve above.

The torque is the twisting force that makes the motor running and the torque is active from 0 to 100 operating speed. Figure 1 provides a graphical illustration of these changes. It is easier to show the relationship in the form of a curve fig. Pull up torque put this term is used for the lowest point on the torque speed curve for an electric motor which is accelerating a load up to full speed.

The induction motor torque speed curve is typical of this type of motor having a low starting torque and a peak torque just below. Torque speed plots in the motoring region. Common features of interest are noted and discussed below. The full torque from zero speed is a major advantage for electric vehicles.

At 60 hertz base motor speed both hp and torque are at 100 percent. Overlaying torque speed curves to match motors to pumps. In this case the relatively large starting torque is achieved with realistic current values. The motor region of the torque speed curve.

The accuracy of the induction motor model has limitations and the actual torque speed characteristic is somewhat more complicated than the model predicts. One is a plot of empirical data and the other was plotted mechanically using a device developed at mit. The y axis is the percent of hp and torque.