Measurement of Contact Travel of High Voltage Circuit Breaker Based on GMR Sensor

To address the issue of contact travel measurement in high-voltage circuit breaker, a non-contact off-axis angle measurement scheme based on the giant magnetostrictive effect is proposed. By studying the structural principles of high-voltage circuit breakers and comparing existing sensor schemes, a non-contact measurement method is selected to avoid the loss and instability issues caused by severe vibration in traditional contact-based methods. Corresponding installation structures are designed to reduce errors resulting from improper installation. By using sensors to monitor the real-time rotation angle of the contact shaft, precise angle information is obtained, and the angle values are converted into contact travel data using conversion formulas for different actuating mechanisms. Experimental results show that the accuracy of this scheme can be up to 0.03°, which is able to meet the requirements for measuring contact travel in high-voltage circuit breaker. Therefore, this scheme holds significant application value in power system maintenance and fault diagnosis, providing an effective means to ensure the safe operation of power equipment.