Electric Motor Torque Power Curve

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.

Electric motor torque power curve.

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 torque available at this point is called pull up torque. As the motor picks up speed torque decreases slightly to the lowest point shown on the curve above. The driving force of an electric motor is torque not horsepower.

Thankfully in electric motors maximum torque is produced from the get go. It is generally known as motor characteristic curve. This also is not very useful except it will determine the maximum available torque. Like pumps motors produce a torque speed curve of their own.

Below is the typical ac induction motor characteristics. The pattern remains same for different hp ratings. The torque of a 60 hp motor rotating at 1725 rpm can be calculated as. The power produced by the motor depends on the speed of the motor and is zero at 0 speed and.

For every motor there is a specific torque speed curve and power curve. In use the motor is driving a propeller. Different electric motor has different characteristics and it can be observed by its torque vs. From zero speed to a maximum determined by the battery voltage the torque curve is a flat line limited by the amount of current the controller will supply to the motor.

T rated torque nm p kw rated power kw n r rated rotational speed rpm example electrical motor and braking torque. The graph above shows a torque speed curve of a typical d c. T fl 5252 60 hp 1725 rpm 182 7 lb ft. The power band of an internal combustion gasoline automobile engine typically starts at midrange engine speeds around 4 000 rpm where maximum torque is produced and ends close to the redline after reaching maximum power between 5 000 and 6 500 rpm.

As a current flows through the electric motor a related electrical charge causes an armature to rotate. Motor characteristics are frequently given as two points on. In other words there is a tradeoffbetween how much torque a motor delivers and how fast the output shaft spins.