Automotive Terms

Three-phase alternator

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Today, all automobiles have three-phase alternators. In contrast to the earlier [ ⇒ DC alternators ] the following advantages should be emphasized:

• Power output already at idle speed
• High maximum speeds are possible
• Little wear; with a long service life of the unit
• Low maintenance
• Power independent
• of the direction of rotation
• ; small dimensions and low weight in relation to the power

The generated current is rectified, since the vehicle electrical system requires direct current.

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Torque

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One of the most important performance data of an engine is the torque with the corresponding speed. Torque is the effect of a force acting on a lever arm around a pivot point. The value "meter kilogram" (mkg) is calculated from the length of the lever arm (in meters) times the force (in kilograms). This is the old designation, today the torque is expressed in "Newtonmeter" (Nm), whereby a Nm corresponds exactly to 0.102 mkg.
The torque curve of an engine as a function of engine speed provides information about the elasticity and pulling power of an engine. The higher the torque and the wider the speed range in which the torque is available, the better. Of course, transmission tuning is also important.

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