Engee documentation

Inverse Park Transform

Coordinate transformation from the dq0 coordinate system to abc.

inverse park transform

Description

The Inverse Park Transform unit converts longitudinal, transverse and zero components in a rotating coordinate system in the time domain into three-phase system components in the coordinate system . The block can store active and reactive powers in the rotating coordinate system, realising an invariant version of the Park Transform. For a balanced system, the zero component is zero.

The unit can be configured to align the axis of the three-phase system with the or axes of the rotating coordinate system at time . The figures show the direction of the magnetic axes of the stator windings in the coordinate system and in the rotating coordinate system , where:

  • The axis and the axis are initially aligned.

park transform 1

  • Axis and axis are initially aligned.

park transform 2

In both cases the angle , where

  • - the angle between the axes and for alignment with the axis or the angle between the axes and for alignment with the axis ;

  • - rotation speed of the coordinate system - ;

  • - time in seconds since the initial alignment.

Equations

The Inverse Park Transform block implements a transformation to align the phase of to the axis as

where

  • , and are components of the three-phase system in the coordinate system ;

  • and - components of the two-coordinate system in the rotating coordinate system;

  • - zero component of the two-axis system in the stationary coordinate system.

For invariant power equalisation of the phase and along the axis, the unit implements the transformation using the following equation:

To align the phase of to the axis, the block implements a transformation using the following equation:

For invariant power equalisation of the phase and along the axis, the block implements the transformation using the following equation:

Ports

Input

dq0 - a vector that contains values in the dq0 coordinate system
vector

Longitudinal, transverse and zero components in a rotating coordinate system .

Data types: Float32, Float64.

θabc - rotation angle, rad
scalar

Angular position of the rotating coordinate system. The value of this parameter is equal to the polar distance from the phase vector а in the coordinate system to the initially aligned axis of the coordinate system .

Data types: Float32, Float64.

Output

abc - vector, which contains values in abc coordinate system
vector

Components of a three-phase system in the coordinate system .

Data types: Float32, Float64.

Parameters

Phase-a axis alignment - axis along which the dq0 coordinate system will be aligned
Q-axis (by default) | D-axis

Align the phase of the coordinate system to the axis or to the axis of the rotating coordinate system .

Power Invariant - power invariant transformation
off (by default) | on

Option to save active and reactive power in the coordinate system .

References

[1] Krause, P., O. Wasynczuk, S. D. Sudhoff, and S. Pekarek. Analysis of Electric Machinery and Drive Systems. Piscatawy, NJ: Wiley-IEEE Press, 2013.

Additional options

C code generation: Yes