Development of a Double-Resolver High-Sensitivity Torsion Spring-Type Torque Sensor via Iterative Error Self-Compensation Method

A torque sensor is one of the most widely used sensing technologies in modern rotating machinery. It is extremely significant in designing the sensing element with high sensitivity and angle measurement accuracy. This study proposes a double-resolver high-sensitivity torsion spring-type torque sensor via the iterative error self-compensation method. For the first time, the torsion spring and the double resolver are used as a sensing element and a measuring part in the sensor, respectively. Here, the iterative error self-compensation method is presented to solve the problems of unequal amplitude and nonorthogonal phase of the excitation signal. Moreover, the problem of zero error is solved. Furthermore, a phase measurement system based on the field-programmable gate array (FPGA) is designed to achieve a high-precision torque measurement. Here, experiments are performed to verify the feasibility and effectiveness of the proposed sensor. The results show that the proposed sensor has outstanding angle measurement accuracy, sensitivity, and other statistical characteristics. Hence, it has a potential application prospect in the field of new-energy vehicles.