Patent ID: 8188896
Filing Date: 2012-05-29
Classification: H03M

Abstract:
1. A digital converter to process two output signals of a resolver attached to a rotating apparatus, comprising: first and second ΔΣ AD converters configured to convert the two output signals into digital signals; first and second multiplication units configured to receive the digital signals outputted from the first and second ΔΣ AD converters; a subtraction unit configured to subtract outputs of the first and second multiplication units; a synchronous detection unit configured to detect the output of the subtraction unit synchronously based on a synchronization signal; an angular velocity calculation unit configured to adjust a proportional gain of an output of the synchronous detection unit, to compensate the phase of the output of the synchronous detection unit, and to calculate the angular velocity of the rotating apparatus; a rotational angle calculation unit configured to calculate the rotational angle of the rotating apparatus by integrating the angular velocity; and a cosine output unit and a sine output unit configured to output a cosine and a sine corresponding to the obtained rotational angle to the first and second multiplication units, respectively.