Research On The Permanent Magnet Linear Synchronous Motor Drive System For Electromagnetic Launcher

With the development of modern-ocean military, the carrier fighting capability of the aircraft was urgently required to be stronger and stronger. It proposed an extremely high requirement for the aircraft carrier launching device which was used in driving the carrier-based aircraft taking off, so the present steam launching device is difficult to meet the huge mass launching condition. Compared to steam launching device, the electromagnetic launching device has become the researching focus benefiting for its little mass, small volume, high efficiency, low maintain cost and high control precision character. But, at present, the research on electromagnetic launching device is a new area in our country. By the domestic military power developing, the aircraft carrier is necessary equipment for our country, so the carrying research on electromagnetic launching has great significance for enhancing our country military force, manufacturing top weapon, breaking the foreign technology blockade, shorten the distance between our country and military powerful country, boost the national defense career and safeguarding the word peace.The dissertation inosculate the aircraft carrier launching device requirement that large thrust, low torque fluctuation and high speed performance, designed the electromagnetic launching system driving scheme, which based on autonomous decentralized architecture. And take further researching on its driving system structure, position detection, control scheme and fault tolerance. On this basis, the prototype test platform for electromagnetic launching driving system was built independently, which is composed of AC permanent magnet linear synchronous motor (PMLSM), lower volt AC servo controller and linear displacement sensor. And, the validity and accuracy of this method for electromagnetic launching performance requirement which was proposed in the dissertation were verified through the experimental results.According to the electromagnetic launching technology requirement, the factors which influence the efficiency of electromagnetic launching driving system were analyzed, and the method that adopts cogging PMLSM in low speed interval and adopts slotless PMLSM in high speed interval to enhancing the system efficiency in launching process was proposed. In order to enhance the manufacturability and the modular error repair ability, the AC permanent magnet linear synchronous motor driving system structure which is composed by stator modular was proposed. As to release the driving system power supply requirement and enhance the control stability, the method that using little power motor modular combination to instead huge power motor was proposed. The finite element method to deeply research on AC permanent magnetic linear synchronous motor was adopted. And the polar distance influence on motor power density and the structure parameter influence on thrust and thrust fluctuation in cogging motor and slotless motor were analyzed to provide a reference principle for design on the AC permanent magnet linear synchronous motor that used in electromagnetic launching.In order to realize high speed servo control for driving system, in position detection unit, three phase and six component signal pick-up method basing on hall effect were adopted, and the signal error that induced by assembling deviation and zero-drift was eliminated by difference processing method. At the same time, based on the lookup signal processing algorithm, the two column magnetic steel arrangement which contains the lookup column and encoding column were adopted. The linear magnetic grid displacement sensor was designed. The experimental results show that the sensor could get a high resolution, and it establish the foundation for realizing absolutely displacement high precision detection and high speed motor control.According to the defect exist in traditional integrate control, decentralized autonomous control method was proposed, and the autonomous decentralized system control structure was constructed. The vector control electro-magnet model and electro-magnet thrust model for permanent magnet synchronous motor were derivated, and a theoretical basis for its implementation was provided. In the permanent synchronous control under decentralized autonomous structure, in order to enhance the current responding character, the back EMF compensation method was adopted, and its validity by the simulation was verified. At the same time, in order to enhance the velocity detection precision and solving the delay question result by velocity feed back, the state observer in the mechanical loop to obtain the real-time position and velocity feed back, were introduced, as to enhance the velocity responding frequency and the position control precision of the permanent magnet synchronous linear motor.In order to enhance the redundancy of the electromagnetic launching drive system, 8 polar 12 slot integrate winding permanent magnet synchronous linear motor was taken as the main research object. The total magneto motive mathematical model was derivated when single phase stator modulars failure, as well as single modular, double modulars, and three phase intercross modulars failure situation. On this basis, in order to maintain the total magneto motive unchanged, the current mathematical compensation model in different situation was derivated, the magneto motive compensation was realized, and instantaneous thrust the same with the normal situation was ensured, which even more enhance the reliability and the error dealing ability.The cogging principle prototype in low speed interval and slotless principle prototype in high speed interval for experiment system was developed, and test on its performance was taken. The experimental results proved the validity of adopting cogging PMLSM in low speed interval and slotless PMLSM in high speed interval could enhance the system efficiency, it also testified the correctness of the current compensation models when different modulars failure. These researches in the dissertation established the application foundation that using electromagnetic launching technology in aircraft carrier launching device could realize high precision, high power launching.