Accurate calculation of the inductance of the d-q axis is very important for the accurate current control of the Permanent magnet linear synchronous motor（PMLSM）, but the inductance of the d-q axis in the saturated permanent magnet motor will change continuously with the working conditions. Considering the end effect and magnetic saturation, this paper proposes a method for calculating the uncertainty range of the inductance parameters of the d-q axis for PMLSM. First, use the multi loop analysis method to calculate the winding inductance. Second, use the finite element method to calculate the PMLSM nonlinear incremental inductance. Third, Establish nonlinear incremental inductance model function, Finally, from the obtained nonlinear incremental inductance, the uncertainty range of PMLSM's d-q axis inductance parameters can be obtained through the d-q axis inductance formula and the analysis of the influence of current on the inductance.

PMLSM， d-q axis inductance， FE method， end effect， magnetic saturation