Reliability Analysis And Study On Complex Environment Application For Levitation Sensor In Middle-low Speed Maglev Train

Middle-low speed maglev train is a new type vehicle that has no contact with the orbit.This non-contact levitation operation mainly relies on the levitation controller to adjust the electromagnetic suction of the electromagnet in real time through the levitation sensor.The basic condition of the levitation system to achieve stable and reliable levitation is that the levitation sensor must provide reliable,accurate gap signal and acceleration signal for the control system.And the levitation sensor is mounted at the end of the electromagnet,below the maglev train track,and is subject to the possibility of failure and fault which is affected by the complex environments such as electromagnetic disturbance,vibration shock and wide range of temperature changes.In order to achieve stable and safe operation of the levitation control system,the levitation sensor,as an electronic device,must design,analyze and improve its reliability on the basis of its basic functions.Based on the analysis of the reliability of the sensor,this paper focuses on the application of complex electromagnetic,vibration,temperature and other environmental conditions,the main contents and conclusions include:1.The reliability design theory is used to analyze the function modules of the levitation sensor system in detail,and the inherent reliability of the levitation sensor is calculated.The failure mode effects and criticality analysis of the levitation sensor is carried out,and the possible faults and potential defects of the levitation sensor are pointed out.2.The modal analysis of the levitation sensor is carried out by means of the theoretical modal analysis method.The natural modes and modes of the levitation sensor are obtained.Combined with the resonant sweep test,the resonant frequency of the levitation sensor is determined.According to the actual working environment of the levitation sensor,the experimental was carried out to verify if the cantilever structure has effect on the normal output of the sensor.And the experimental results show that the cantilever structure has no effect on the output of the sensor.3.Analyzed the electromagnetic environment evaluation of the sensor,combined with the actual working condition of the sensor,the anti-electromagnetic interference index is confirmed.In addition to the common ground design and shielding measures,special anti-interference designs are applied in power and signal channels,which improves the sensor immunity to surge,EFT,etc.The corresponding tests are carried out and passed,which proves the efficiency of the design.4.The finite element analysis software is used to build the thermodynamic model of the levitation sensor system.Based on the thermodynamic model simulation analysis,the temperature field distribution of the digital plate is calculated and the rationality of the digital board circuit design is determined.According to the fact that the temperature field of the levitation sensor changing largely,comprehensively comparing the traditional temperature compensation method,a new temperature compensation method based on software algorithm is proposed,and the effectiveness of the temperature compensation method is verified by experiments.Research is conducted in sequence of vibration analysis,electromagnetic compatibility design and thermal analysis and temperature compensation.Parts of the theories and methods proposed have been successfully applied in the levitation sensor and remarkable promotion has been received in the reliability of the levitation sensor.