A Dynamic Method for Magnetic Torque Measurement

In a magnetic suspellsio~ls ystem, accurate force meas~irementw ill result in better colitrol performance in the test scection, especially w11e11a wider range of operation is required. Although many useful methods were developed to obtain the desired model, however, significant error is levitable since the magnetic field distribution of the large-gap magnetic suspension system is extremely nonlinear. This paper proposed an easy approach to measure the magnetic torque of a magnetic suspensiob system using an angular photo encoder. Through the measurement of the velocity change data, the magnetic torque is converted. The proposed idea is described and implemented to obtain the desired data. It is useful to the calculation of a magnetic force in the magnetic suspension system.