Research On High-precision Precision Magnetic Encoder And Its Subdivision Algorithm

Angular displacement detecting sensor is the critical component of the servo-loop control system’s real-time feedback and dynamic monitoring.The magnetic encoder of the paper has anti-vibration, anti-pollution,high reliability, etc compared with the widely used photoelectric encoder, so that it is more and more popular applied in some special occasions such as military field. However, the current magnetic encoder studied in our own country is far behind foreign developed products and markets quantity demand grow, increasing high precision to magnetic encoder. Therefore this paper thoroughly research encoder in resolution and accuracy, then verify specific design specifications; the high-precision multi-pole magnetic encoder is designed for high-precision required measurement field, the subject of study has some practical value.This paper first analyzes the advantages and disadvantages of the traditional arctangent and calibration look-up table, and then propose a new partitions arctangent look-up algorithm, which has a range of continuity and the advantages of small nonlinearity; detailedly introduce this algorithm’s tabulation and table lookup process, put forward multi-pole encoder algorithm inspired by the mechanical watch. Then according to the gap size of the gap optimization design the encoder signal generating mechanism; the key techniques of the encoder are discussed, for example oversampling technology of AD devices improve sampling resolution to eliminate the white noise, and the data acquisition card solver accuracy and resolution of the encoder. When the calibration is in detected status, the single-pole encoder that is developed in axially mounted achieve12-bit precision and16-bit resolution. Multi-pole magnetic encoder of the original signal is blowed up by the amplifier, which extend AD range utilization, whose resolution is23-bit by the experiment. At last, based on large motors, single and multi-pole magnet of the magnetic field on the simulation results verify interference effects between the one-on-pole magnet and multi-pole magnetic field. And proposed model modifications-increasing magnetic boards, it prevents two magnets superimposed in the magnetic field on the region of interest, then the magnetic field simulation result shows that the magnetic field in order to be isolated, so eliminates the multi-polar signal on the low-frequency signal.The experiments prove that the studied encoder has reached high accuracy, high resolution indicators, and can meet the application of certain special occasions.