Resolver device

Abstract

An n-th-harmonic error estimation unit that estimates the error component of an n-th harmonic included in a resolver angle θ and a subtraction unit that subtracts an n-th-harmonic estimated angle error from θ to output the corrected angle θ' are included. The n-th-harmonic error estimation unit includes an n-th-harmonic error phase detection unit that obtains a phase difference u such that the integral, for a 1/n period of an electrical angle of the rotor, of the output obtained by synchronously detecting θ by using a rectangular wave obtained by comparison from a COS wave expressed as cos(nθ+u) becomes zero and generates a SIN wave expressed as sin(nθ+u); a synchronous detector that synchronously detects θ′ by using a rectangular wave obtained by comparison from the SIN wave; an integrator that integrates the detected output for a 1/n period of the electrical angle; an actual angle integral calculation unit; an amplitude setter that sets an error amplitude from the value obtained by subtracting the integral of the actual angle integral calculation unit from the integral of the integrator; and a multiplier that generates the n-th-harmonic estimated angle error by multiplying the SIN wave by the error amplitude.