In order to make a further improvement in linear motor's thrust density,a novel structure of cylindrical linear motor with Halbach array of trapezoidal permanent magnet (TH-CLM) is proposed by combining cylindrical linear motor with trapezoidal permanent magnet (T-CLM) with traditional Halbach array.Magnetic circuit analysis model of TH-CLM is built.The influence of permanent magnet's shape to magnetic field and thrust is studied,and optimal angle of permanent magnet to obtain the maximum thrust density is ...