Magneto-electric sensor is one of the sensors widely used in the field of measurement. It is also known as the electrodynamic sensor or electromagnetic induction sensor, it is the use of magneto-electric effect will be measured into electrical signals of the sensor, a generation of sensors, it USES the principle of electromagnetic induction. Magneto-electric sensors generally convert speed into induced electromotive force output. Magneto-electric sensor has many kinds, and magneto-electric speed sensor, because of its simple structure, small volume, no power, can be directly from the object being measured mechanical energy into electrical signal output, has strong anti-interference ability, the advantages of wide scope of heat-resistant, commonly used in electronically controlled engine to determine the speed and position of the crankshaft.