螺旋桨的永磁无刷直流电机绕组换接驱动方法

A Winding Connection Method for Driving Propeller's PM Brushless DC Motors

螺旋桨转矩与大气密度成正比,飞艇最高飞行高度海拔30 km处大气密度为0 km处的1/66,若保持相同转速,0 km的转矩是30 km处的66倍,常规永磁无刷直流电机（brushless DC machines,BLDCM）难以兼顾对高、低空螺旋桨负载的匹配,限制了飞艇飞行高度范围。为此提出利用调节BLDCM磁链的解决思路,进而提出一种BLDCM绕组换接方法,绕组并联减小磁链,满足高空下电机高速运行需求,绕组串联增加磁链,减小电机电流,满足电机低空低速大转矩需求。对不同绕组模式电机性能进行了理论分析,研究了绕组换接BLDCM的设计方法,设计并测试了1台3.5 k W BLDCM样机,样机不同绕组模式下性能测试结果与理论分析相吻合,证明该绕组换接方法可使BLDCM满足0~30 km高度空间内螺旋桨负载驱动的转矩和转速需求。

Since the torque of a propeller is proportional to the atmospheric density and the atmospheric density at the airship＇s highest flight altitude of 30 km is 1 / 66 that of 0km,its torque at the altitude of 0 km is 66 times that of 30 km if the propeller rotates at the same speed. The flight altitude of the airship is limited because a normal brushless DC motor（ BLDCM） cannot match the load of the propeller at high and low altitudes. In order to match the load,we adjust the flux linkage of the BLDCM and propose our winding connection method. The winding parallel connection decreases the flux linkage and achieves the high speed of the BLDCM at high altitude; the winding series connection increases the flux linkage and decreases the electric current to achieve the large torque of the BLDCM at low altitude and speed. We perform the theoretical analysis of the performance of the BLDCM that has various winding connections and then design and test a 3.5 k W BLDCM prototype. The test results on the performance of the prototype that has various winding connections agree well with the theoretical analysis results,indicating that our winding connection method can satisfy the propeller＇ s requirements for the torque and rotational speed of the BLDCM in the range from 0 to 30 km.