Patent ID: 8280565

Claim:
A drive control apparatus for an electric car wherein a three-phase AC voltage is generated by a VVVF inverter, and a linear induction motor is driven by the three-phase AC voltage, the drive control apparatus comprising: current detection means for outputting instantaneous value information of a three-phase AC current which flows from the VVVF inverter to the linear induction motor on the basis of the three-phase AC voltage; three-phase/two-phase conversion means for converting the instantaneous value information of the three-phase AC current into two-phase current information and outputting the two-phase current information; axle rotational-frequency information output means for outputting axle rotational-frequency information which represents a rotational frequency of an axle of the electric car; wheel-diameter correction information output means including wheel-diameter information calculation means for calculating wheel-diameter calculation information representing a wheel diameter of the electric car on the basis of the two-phase current information, and configured so as to be capable of outputting the wheel-diameter calculation information as wheel-diameter correction information; synchronizing-frequency calculation means for calculating synchronizing frequency information representing a synchronizing frequency of the linear induction motor on the basis of the axle rotational-frequency information and the wheel-diameter correction information; and vector calculation control means for outputting a control command for the VVVF inverter, on the basis of a torque command, the two-phase current information and the synchronizing frequency information.