Digital-shaft angle signal converting method

The invention provides a digital-shaft angle signal converting method. The method is characterized in that: a circuit realizing the method comprises a digital-sine and cosine signal converting circuit, an electronic wide-frequency and wide-voltage SCOTT transformer and a digital signal processor (DSP), wherein the digital-sine and cosine signal converting circuit consists of a subdivision circuit and a rough division circuit; the subdivision circuit is a resistance network digital/analogue (D/A) conversion circuit which is less than 16 bits; the rough division circuit consists of a precise resistance network, a precise operational amplifier and an analogue switch; and the electronic wide-frequency and wide-voltage SCOTT transformer consists of a mode operational circuit, a voltage amplitude value operational circuit and a power driving circuit. Full electronic technology is adopted by the digital-shaft angle signal converting method; a wide-frequency and wide-voltage differential synchro signal or rotary transformer signal can be output; the conversion precision is high; and the expandability is high.