Speed Regulation Characteristics of Variable Conductivity-Based Barrel-Type Permanent Magnet Eddy Current Governor

In this study, a conductivity-regulated barrel-type permanent magnet eddy current governor is proposed, and a conductor barrel structure scheme consisting of four sections of materials with different conductivities is presented. The torque equation of the barrel-type permanent magnet eddy current governor with the equivalent conductivity as the covariate was established using the separation variable method based on the subdomain model. The equivalent conductivity function was established to obtain the speed regulation characteristics of the governor under a constant torque load, and the calculation method for the governor’s transmission efficiency was provided. The influence of the conductivity parameters of the conductor barrel on the speed regulation characteristics was studied by numerical simulation, the influence of the conductivity values of each Section of the material on the conductivity function was investigated, the torque equation and conductivity function were verified by three-dimensional electromagnetic finite element simulation, and the direction and distribution of eddy current in conductor layer under different working conditions were simulated. The results show that the structural scheme of the four-segment combined conductor barrel can realize a continuous change in conductivity with the displacement of the magnet disk, thus realizing continuous speed regulation of the constant torque load, and the speed regulation characteristic of the governor is segmented linearly. Compared with the air gap-regulated disk-type permanent magnet eddy current governor, the conductivity-regulated barrel-type permanent magnet eddy current governor has a wider speed regulation range, a lower unloading torque after overload protection, and can start with its maximum torque, thus enabling heavy-load starting of constant torque loads, speed regulation operation, and unloading overload protection of equipment.