Study on the Characteristics of Electromagnetic Noise of Axial Flux Permanent Magnet Synchronous Motor

Table 4

Calculation and test results for natural frequencies of stator core of 15 kW motor.

(𝑛,𝑠)	𝐾𝑚^(𝑐) /M N·m^−1	𝑓ma/Hz	𝑓me/Hz	err/%
(2, 0)	91.75	258.3	280	−7.75
(3, 0)	777.42	691.2	675	2.40
(1, 1)	238.67	1174.5	1135	3.48
(4, 0)	2746.05	1265.0	1313	−3.65
(5, 0)	6943.36	1985.2	2040	−2.68

Remark: n is pitch diameter number; s is pitch circle number; 𝑓_ma is calculation natural frequency; 𝑓_me is measured value of natural frequency; err is relative error.