Design And Experimental Study Of Angular Displacement Sensor With Shared Magnetic Field

As an important industrial product,the sensor has been playing a role of measuring information flow medium,and it is responsible for evaluating and supervising the quality and safety of other industrial products.After more than 20 years of development,the technology of time grating displacement sensor tends to be mature,and its products are gradually diversified.The development direction of the magnetic field time grating angular displacement sensor is to output absolute angular position and self-tuning,but limited by the mutual interference between the mechanical structure size and winding,the feasible technical condition to realize the two functions at present is only two-layer coaxial sensor coaxial installation.Because of the difference of mechanical structure,winding and hardware circuit between the two sensors,the angular displacement measurement of the two-layer coaxial sensor has a large error.By combining the outer stator of the two-layer coaxial sensor into a stator and providing an exciting magnetic field to the inner two-layer rotor,the mechanical structure of the sensor is improved and the winding and hardware circuit are simplified.In the specific content,this paper first analyzes the generation principle of the shared magnetic field based on the time grating principle,and studies the absolute measurement method of the shared magnetic field angular displacement sensor.This paper briefly introduces the definition,measurement principle and technical advantages of time grating,deduces the relationship between the magnetic flux of the shared magnetic field and the angular displacement,determines the sensor structure of 1 stator + 2 rotor,gives the self-adaptive sine winding distribution formula,and carries out the simulation verification through Maxwell,at the same time,uses the relationship between the angular displacement and the absolute angular position and combines the pole number and deduces the measurement method of absolute angular position of sensor.Then,the stator structure design based on the magnetic equivalent circuit is proposed.The stator,which is the source of the shared magnetic field,is designed with high efficiency.The mathematical model of the magnetic equivalent circuit is established,the calculation formula of the magnetic conductivity is derived,and the induced voltage is calculated.Compared with the simulation results of the same structure,the difference is less than3%,but the time-consuming is greatly reduced.Finally,the size of the stator structure is determined by the magnetic equivalent circuit method: trapezoid slot gap.Trapezoidalgroove height.Tooth width.Air gap length.Then,the structure design without slip ring based on inductively coupled power transfer(ICPT)module is proposed.Because of the electrical error and speed limitation of mechanical slip ring itself,it is not conducive to the improvement of sensor accuracy and the realization of high speed.Through the design of ICPT module,sensor mechanical structure and circuit PCB Based on ICPT module,and the integrated design of sensor system based on ICPT module,the measurement of shared magnetic field sensor without mechanical slip ring is realized.The prototype is made,and the experimental research on the principle based,magnetic equivalent circuit based and ICPT based shared magnetic field angular displacement sensor is carried out.In the range of 0?-360?,the original error amplitude of the 25 pair pole rotor of the principle sensor is 610?,and that of the 64 pair pole rotor is 350?.Based on the magnetic equivalent circuit,the original error amplitude of 25 pairs of pole rotor is 190?,and that of 64 pairs of pole rotor is 120?.Based on ICPT,the original error amplitude of 25 pairs of pole rotors is 120?,and that of 64 pairs of pole rotors is 90?.Three experimental studies have gradually achieved the improvement of measurement accuracy of the shared magnetic field angular displacement sensor.Finally,the absolute angular position output of the sensor based on the ICPT module is completed,and the self-correction method based on the error coordinate transformation is used to correct the measurement error of the principle sensor.In conclusion,this paper completed the theoretical analysis,prototype design and experimental research of the shared magnetic field angular displacement sensor,realized the successful improvement of the magnetic field time grating angular displacement sensor,and promoted the research work of the time grating sensor in the industrialization stage.