Automobiles have a variety of electrically operated drives. Be it the sunroof, the window lifter, the seat adjustment or the trunk lid, everywhere you look, you’ll find electric motors that provide us comfort in our cars.
For the testing of these e-drives, we implemented the data acquisition solution and evaluation for a large German automotive supplier.
Power consumption and speed are relevant to evaluating the efficiency of electromechanical systems. Since the motors are permanently installed into vehicle body parts, often only the electrical current and voltage signals are all that’s available for quality testing.
Using the Current Signal to Determine Motor Speed
In a classic DC motor, the mechanical commutator leads to a brief drop in the current curve when poles are reversed. Depending on the design and number of poles of the motor, the quantity of current dips corresponds to one revolution. This model is also reflected in the current curve of brushless motors with electronic commutation.