ELECTRIC POWER STEERING DEVICE

PROBLEM TO BE SOLVED: To provide a technology which can impart an assist force corresponding a change of a traveling road face state while suppressing the lowering of a steering feeling.SOLUTION: An electric power steering device comprises: a fundamental target current calculation part which calculates a fundamental target current being a base of a target current supplied to an electric motor on the basis of steering torque; a correction current decision part 28 which has a fundamental steering angle speed deviation current calculation part 281 for calculating a fundamental steering angle speed deviation current Ivf corresponding to deviation between a calculated target steering angle speed and an actual steering angle speed on the basis of the steering angle which is detected by a steering angle speed calculation part, and calculates a correction current which is obtained by correcting the fundamental steering angle speed deviation current Ivf on the basis of a change of a friction coefficient of a traveling road face of a vehicle; and a target current decision part which decides the target current on the basis of the fundamental target current and the correction current.SELECTED DRAWING: Figure 6 【課題】操舵フィーリングの低下を抑制しつつ、走行路面状況変化に応じたアシスト力を付与することができる技術を提供する。【解決手段】操舵トルクに基づいて電動モータに供給する目標電流の基本となる基本目標電流を算出する基本目標電流算出部と、操舵角算出部が検出した操舵角に基づいて算出した目標操舵角速度と実際の操舵角速度との偏差に応じた基本操舵角速度偏差電流Ｉｖｆを算出する基本操舵角速度偏差電流算出部２８１を有し、車両の走行路面の摩擦係数変化に基づいて、基本操舵角速度偏差電流Ｉｖｆを補正した補正電流を算出する補正電流決定部２８と、基本目標電流と補正電流とに基づいて目標電流を決定する目標電流決定部と、を備える。【選択図】図６