Research On Performance Test Method Of The Planar Switched Reluctance Motor System

Planar switched reluctance motors(PSRMs) are novel special electrical machines, PSRMs are shown to be an attractive candidate in advanced manufacturing industry, owning to their advantages of direct drive, simple structure, high reliability and precision, and large range, etc. For studying on the design theory and control strategy of the PSRM, which has made progress up to now, nevertheless, research on PSRM system testing for its performance parameters and characteristics is not scientific and systematic. This paper mainly focuses on performance test of the PSRM system, then designs and achieves a friction compensation control algorithm of the PSRM system based on the Lu Gre friction model.Firstly, the structure and working principle of the PSRM are clarified, the experiment platform of the PSRM system is built and described, the mathematical model of the PSRM is derived, and the performance parameters and characteristics of the PSRM system are analyzed.Secondly, for the mechanical parameters and characteristics of the PSRM system, the test schemes for them are respectively designed. The mechanical parameters of the PSRM are given, the static normal force of the PSRM is measured with the strain gage, the dynamic normal force of the motor is tested with the vibration accelaration sensor, the inherent frequency of the motor is obtained by finite element modal analysis under ANSYS software and the modal experiment, the acoustic noise of the motor is measured by the acoustic pressure sensor. The test results show that: 1) the main reason for vibration of the PSRM is the normal force ripple, when the frequency of the normal force is close to the inherent frequency of the motor, the PSRM will generate considerable vibration; 2) the acoustic noise of the PSRM is connected with the exciting current, the moving trajectory of the motor, and the control strategy; 3) the inherent frequency of the PSRM can be avoided via efficient control algorithm, thus the PSRM can achieve vibration damping and noise reduction.Then for the motor parameters and characteristics of the PSRM system, the test schemes are designed. Among them, the inductance of the mover is measured using the LCR gauge, the mutual inductance between the mover and the near mover is gained by the volt-ampere measurement method, the flux linkage of the mover winding is indirectly tested based on the step voltage method, then the thrust force is calculated with the obtained flux linkage, the resultant force is measured by the dynamometer. The test results show that the motor characteristic of the PSRM system is complex nonlinear, which is related to the phase current and the overlapped position between the mover and the stator.Additionally, since the friction seriously hinders high kinematic accuracy movement of the PSRM system, the friction model based on Lu Gre model of the PSRM in X- and Y- axes are formulated, and the corresponding parameters of the Lu Gre friciton model are identified, an observer is established to estimate the friction of the PSRM, the friction compensation control algorithm for the PSRM system based on Lu Gre model is designed, the stability of the PSRM system with the friction compensation is analyzed, and simulation and experiment for the PSRM system with Lu Gre friciton model are carried out, then the control performance of the PSRM are tested under two cases, one is without the friction compensation control algorithm, the other is with the friction compensation control algorithm. The results demonstrate that when the friction compensation control algorithm is employed to the PSRM system, the traceability of the PSRM system improves, the dynamic position errors decrease by more than 40% compared to the PSRM system without the friction compensation control algorithm, the kinematic accuracy obviously increases, the correctness and effctiveness of the friction compensation control algorithm for the PSRM system are verified.