AD2S105

The AD2S105 performs the vector rotation of three-phase 120 degree or two-phase 90 degree sine and cosine signals by transferring these inputs into a new reference frame which is controlled by the digital input angle f. Two transforms are included in the AD2S105. The first is the Clarke transform which computes the sine and cosine orthogonal components of a three-phase input.

These signals represent real and imaginary components which then form the input to the Park transform. The Park transform relates the angle of the input signals to a reference frame controlled by the digital input port. The digital input port on the AD2S105 is a 12-bit/parallel natural binary port. If the input signals are represented by Vds and Vqs, respectively, where Vds and Vqs are the real and imaginary components, then the transformation can be described as follows: Vds' = Vds Cosf Vqs Sinf Vqs' = Vds Sinf + Vqs Cosf Where Vds' and Vqs' are the output of the Park transform and Sinf, and Cosf are the trigonometric values internally calculated by the AD2S105 from the binary digital data f.

The input section of the device can be configured to accept either three-phase inputs, two-phase inputs of a three-phase system, or two 90 degree input signals. The homopolar output indicates an imbalance of a three-phase input only at a userspecified level.