Research on control algorithm of strong magnetic interference compensation for MEMS electronic compass

In view of the complicated data acquisition process of traditional MEMS electronic compass compensation methods and the inability to achieve high-precision compensation under strong magnetic interference, this paper studies a compensation method with an external three-axis coil. Firstly, the error modeling of the magnetometer is carried out, and two methods of compensation without heading reference based on M-estimates and compensation with heading reference are introduced. We built a hardware circuit on the basis of a physical coil, used a PXI industrial computer as the data acquisition and processing center, provided current excitation for the coil through a voltage-controlled constant current source, and used LabVIEW to design a control program. Finally, we comprehensively evaluate and verify the feasibility and compensation accuracy of the proposed scheme through vehicle-mounted tests. The test results show that: a heading reference compensation algorithm has higher compensation accuracy, the compensated heading error is within +/- 1.5 degrees, and the standard deviation is below 0.8 degrees, which meets the needs of car navigation.