Electric Motor Torque Curve

The torque delivered from an electrical motor producing 0 75 kw 750 w at speed 2000 rpm can be calculated as.

Electric motor torque curve.

Motor characteristics are frequently given as two points on this graph. In the first cartesian dial are shown the torque in nm x axis the rotation speed in rpm y1 axis the current consumption in a y2 axis the efficiency y3 axis. T 9550 pkw nr 2 where. Slowly ascending upwards before peaking and dropping back down.

You ll all be familiar with the look of a torque curve. 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. As the motor picks up speed torque decreases slightly to the lowest point shown on the curve above. For completeness only in this graph is represented also the output power curve in w y4 axis.

Power kw torque nm example torque from an electrical motor. Nr rated rotational speed rev min rpm in metric units the rated torque can be expressed as. Like pumps motors produce a torque speed curve of their own. In other words there is a tradeoff between how much torque a motor delivers and how fast the output shaft spins.

In this overlay the shaded area reflects the accelerating torque available from the motor to drive the pump. The torque available at this point is called pull up torque. Note that torque is inversely proportioal to the speed of the output shaft. The graph above shows a torque speed curve of a typical d c.

By overlaying the torque speed curve of a pump and a motor one can verify that the motor is producing enough accelerating torque to drive the pump to full speed as shown below. T full load torque lb ft php rated horsepower. For every motor there is a specific torque speed curve and power curve. T 750 w 9 549 2000 rpm.

Torque nm speed rpm electric motor speed vs. A small mound compared to a power curve s steep incline. In this case unless external limitations are applied the maximum torque is achieved at low rpm. For example the ac motor found in the tesla roadster 2008 produces near constant maximum torque from 0 to about 6000 rpm while maximum power occurs at about 10000 rpm long after torque begins to drop off.

In imperial units the full load torque can be expressed as. 1 lb ft 1 355 nm torque converter.