| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotation angle detection device and an electric power steering system, which calculate a rotation angle of a detection object at a higher probability than that of the conventional one.SOLUTION: The rotation angle detection device includes: a resolver that outputs, on the basis of an input of an excitation signal, a resolver signal as a sine signal or a cosine signal, the amplitude value of which changes according to a rotation angle of a motor; and an ECU that calculates the rotation angle of the motor on the basis of the resolver signal. The ECU samples the resolver signal at a 1/4 period, creates two groups, with two sampling points deviated by a 1/2 period defined as one group, determines whether or not the sampling points are normal for each group, and calculates the rotation angle of the motor on the basis of the sampling values of the group determined as normal (a step S47 or a step S49). |
