In a current control system for a cylindrical permanent magnet synchronous motor as the drive source of an electric power steering apparatus, proportional gain Kdp and integral gain Kdi of a d-axis current PI control portion 126 are respectively set to K1Ld and K1Rd on the basis of d-axis inductance Ld and d-axis resistance Rd of the motor. Further, proportional gain Kqp and integral gain Kqi of a q-axis current PI control portion 128 are respectively set to K2Lq and K2Rq on the basis of q-axis inductance Lq and q-axis resistance Rq of the motor (K1 and K2 are optional coefficients). In this case, both of the d-axis resistance Rd and the q-axis resistance Rq have values resulting from adding the external resistance R' including wiring resistance to the internal resistance R of the motor.

 
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