Torque Torque Torque, moment, or moment of force is the rotational equivalent of linear force. The concept originated with the studies of Archimedes on the usage of levers. Just as a linear force is a push or a pull, a torque can be thought of as a twist to an object. The symbol for torque is typically formula_1, the lowercase Greek letter "tau". When being referred to as moment of force, it is commonly denoted by "M". In three dimensions, the torque is a pseudovector; for point particles, it is given by the cross product of the position vector (distance vector)
Cogging torque however, at high speed the motor moment of inertia filters out the effect of cogging torque. A summary of techniques used for reducing cogging torque: Almost all the techniques used against to cogging torque also reduce the motor counter-electromotive force and so reduce the resultant running torque. A slotless and coreless permanent magnet motors does not have any cogging torque. Model railway motors usually have a 2-pole permanent magnet and 3, 5 or 7 poles on the armature to reduce cogging torque. Cogging torque Cogging torque of electrical motors is the torque due to the interaction between the permanent magnets