ABS由轮速传感器，液压控制单元和电子控制单元组成。 Electrical control unit will determine to start anti-lock brake according to the wheel speed which tested by wheel speed sensor.电气控制单元将根据由轮速传感器测试的轮速来决定启动防抱死制动。 Wheel speed sensor can be divided into electromagnetic-type and hall-type.轮速传感器可分为电磁型和霍尔型。 Electromagnetic-type wheel speed sensor is still widely applied in ABS due to its simple structure and low cost.电磁式轮速传感器由于其结构简单，成本低廉而仍在ABS中得到广泛应用。 For electromagnetic-type wheel speed sensor, ABS wheel speed sensor magnets are an essential component.对于电磁式车轮速度传感器，ABS车轮速度传感器磁铁是必不可少的组件。 Addendum and backlash of the trigger wheel will face to pole pin alternately during the rotating of the trigger wheel and thus generate the induced electromotive force due to alternative variation of magnetic flux inside the inductive coil.触发轮的齿顶和齿隙在触发轮旋转期间将交替面对磁极销，并由于感应线圈内部的磁通量的变化而产生感应电动势。 This induced electromotive force will be input to the electronic control unit as a signal.该感应电动势将作为信号输入到电子控制单元。 The frequency of the induced electromotive force will be changed with the wheel speed, therefore, vehicle speed can be measured by the electronic control unit.感应电动势的频率将随车轮速度而变化，因此，可以通过电子控制单元测量车速。
