摘要 |
An electric motor comprising: a magnetic circuit formed by a permanently magnetised element (1) with first and second soft magnetic pole-pieces (2, 3); a magnetic return element (4) providing a path via which flux flows between the pole-pieces (2, 3), the said pole-pieces respectively defining, in conjunction with the magnetic return element (4), first and second radial gaps across which the permanent magnet flux flows; and a system of windings (W1-W4) positioned in the radial gaps and arranged in two groups of two windings. Each group of winding is positioned symmetrically a bout the nominal geometric centre and hence nominal centre of magnetic saliency of a respective one of the first and second pole-pieces. |