Eddy current position sensor operating method for e.g. ABS type electro-hydraulic braking system, involves applying alternating voltages of different frequencies to sensor`s field coil, and determining inductance of coil at each frequency

摘要

The method involves applying, by an electronic unit (11) of a position sensor, two alternating voltages with different frequencies to a field coil (9) of a sensor to electrically excite the coil. Inductance of the coil is determined at each frequency to determine the position of a piston (4) of the sensor. The applied voltages` amplitude and the amplitude of the current circulating in the coil are evaluated for each frequency. Independent claims are also included for the following: (A) an eddy current position sensor (B) a master cylinder for braking system of a motor vehicle comprising an eddy current position sensor.