| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem in which noise resistance is remarkably reduced by constituting a resolver digital converter using software processing means whose operation speed is relatively low and by other means.SOLUTION: Excitation signals Sc are amplitude-modulated by respective modulation waves sin&thetas;, con&thetas;, and modulated waves Sin, Cos in which voltages thereof have been converted by differential amplifier circuits 34, 36 are input into a microcomputer 40. The modulated waves SIN, COS converted into digital data are respectively multiplied by cos&phgr;, sin&phgr; and are applied with subtraction processing, and thereby, an error correlation amount &egr; is calculated. By inputting, into an angle calculation unit 62, a detected amount &egr;c where the error correlation amount &egr; are multiplied by binary detection signals Rd depending on whether the excitation signals are positive or negative, a calculation angle &phgr; is calculated. A sampling timing of the excitation signals Sc is set at a timing when an absolute value of the excitation signals Sc exceeds a specified value. |
