Study On Power Loss Of Line Start Permanent Magnet Synchronous Motor With Different Structures

In order to study the power loss affections of different rotor structures to the Line Start Permanent Magnet Synchronous Motor (LSPMSM), and to get measures of reducing power loss, this thesis take a22kW LSPMSM as an example and studies these meticulously. Firstly, the advantages and shortcomings are separately compared between the analytical method and the Time-Stepping Finite Element Method (T-S FEM) on obtaining the operating characteristics and loss distribution of the prototype operating under with-load and no-load conditions. According to the measured results, it’s shown that the T-S FEM is more reliable.Then, using the T-S FEM, this thesis investigated the impact of the rotor bar material, air-gap length and magnet thickness, no-uniform air-gap length, and nonmagnetic or magnetic slot wedge conditions on the copper loss and iron loss of LSPMSM. The results show that power loss in LSPMSM has many influence factors, and multiple measures are needed to significantly reduce power loss.Finally, compared to the operating characteristics of different scenarios, a more cost-effective scenario with non-uniform air-gap, moderated air-gap length, reasonable magnet thickness is acquired. This scenario is able to maintain that the loss without increasing while the consumption of magnetic decrease significantly. The improved design taking into account the demands of high efficiency, energy saving and cost reduction, with high practical value, provides a good reference for highly efficient energy-saving LSPMSM design.