[Problem]
An object of the present invention is to provide an electric power steering apparatus that has plural dead time compensating functions to compensate the dead time of the inverter without the tuning operation, compensates with the feed forward method by switching the dead time compensating functions corresponding to the steering state, improves the steering performance, improves the distortion of the current waveform and the responsibility of the current control, and suppresses the sound, the vibration and the torque ripple.
[Means for solving the problem]
The present invention is the electric power steering apparatus of vector control system that calculates steering assist command values of dq axes based on at least a steering torque, calculates dq-axes current command values from the steering assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein the electric power steering apparatus has plural dead time compensating functions of which efficiencies to respectively perform a dead time compensation of the inverter are different each other, and performs the dead time compensation by switching from one of the plural dead time compensating functions to an another dead time compensating function with a predetermined condition.