Abstract: Traditional rotational speed measurement based on photoelectric sensors suffers from low accuracy and high susceptibility to interference. To address these drawbacks, this paper proposes a high-precision, high-real-time rotational speed measurement system for wind turbines. With an Anisotropic Magnetoresistive (AMR) sensor as the core component, the system achieves non-contact rotational speed acquisition at the front end by arranging a magnetic incremental encoding ring on the stator flange end. For the backend system, an NI cRIO-9038 embedded controller is adopted, which collaborates in real time with FPGA hardware counting and LabVIEW software to accomplish high-speed pulse capture, composite digital filtering, and 4-20mA industrial signal output. Meanwhile, the system can be seamlessly connected to the main control PLC, providing a reliable data source for precise torque control and stall protection of wind turbines.