Abstract
Abstract
A new type of sensor is presented that offers an alternative solution to existing automotive steering angle sensors required for systems like electronic stability control (ESC). This new approach is based on the assumption that a DC brushless motor is present as part of an electromechanical power steering (EPS) systems. A motor position sensor is already required to control the electric motor which has a direct link to the steering shaft by means of at least one gear depending on the type of steering system. Adding a counter device that detects the number of rotations of the motor, results in an absolute angle sensor covering the total range of the electric motor movement. This counter device or sometimes referred to as the multi-turn device is based on the so called Wiegand effect. This Wiegand counter operates without external voltage supply and is able to detect the motor rotation with zero quiescent current consumption. This steering angle detection method offers a significant cost reduction because it utilizes a motor position sensor already required for the motor control.