|High-speed train is being issued as a one of the most popular transportations lately. The number of high-speed train was increased for customers’ convenience. Yet again, it was left at the mercy of passengers’ comfort and it would be improved with active suspension because of better performance in its satisfactory control and vibration suppression ability. To reduce lateral vibration of the high-speed train, active suspension, tubular permanent magnet actuator(TPMA) in particular, is suggested because of the high thrust density in restricted space and its outstanding control performance. This paper, therefore, proposes magnetic equivalent circuit(MEC) for tubular permanent magnet actuator with quasi-Halbach magnet array. Also three methods as to analyze magnetic flux density of TPMA are introduced. Among them, lumped parameter method can analyze effectively with simple mathematical modeling Magnetic flux density in air gap can be estimated through MEC, and to verify it, FE model is used as a criterion for judging validity. Also end effect of the model could be find in the results as an error.