径向调制永磁齿轮磁极数量对传动特性的影响研究

Study on Influence of Number of Permanent Magnetic Pole Pair on Transmission Characteristic of Radial Modulated Permanent Magnetic Gear

对于永磁齿轮,每一个传动比都可以由主、从动磁极对数量的若干种组合方式来实现。为此,以i=5和相近的传动比为例,选取主、从动磁极对的数量为2/10、3/15、……、7/35共6种组合方案和两组验证对比方案(每组各6种),应用有限元仿真技术,研究了磁极对数量对输出转矩和传动效率的影响。结果表明,输出转矩随磁极对数量的增加呈二次曲线规律变化,且峰值出现在主动磁极对数P_h=4处;而传动效率基本也呈二次曲线变化规律,在P_h=4～7处出现较大的值,但是变化不大。综合考虑输出转矩和传动效率,当传动比在i=5附近时,选取主、从动磁极对数量的组合方案P_h/P_l=4/19,可以获得较好的传动特性。

For permanent magnetic gears (PMGs), each transmission ratio can be made by several combinatio ns of the numbers of magnetic pole pairs (NMPP) on the driving and drive n rotors. In order to investigate the influence of NMPP on transmission efficiency and output torque, transmission ratio i=5 is selected, PMGs with 6 combi nations of NMPP and corresponding two groups (each group has 6 combinations) are analyzed, the 6 combinations of NMPP on driving/driven rotors are 2/10, 3/15,…,7/35. Finite element analysis (FEA) simulations indicate that variations of output torque to NMPP on driving rotor (Ph)are quadratic curves with peak values occurring at Ph=4, variations of transmission efficiency to Ph also show quadratic curves basically but with slow change and a little higher values occurring at Ph=4 7. So it is concluded that considering output torque and transmission efficiency together, for PMGs with transmission ratio i being close to 5, the NMPP on driving/driven rotors (Ph/P1) should be selected as 4/19 to get a better transmission characteristics.