Definitions of direct axis (d-axis) and quadrant axis (q-axis) 3

[Sparky35]

I have stumbled on these in a project that i am currently working on, just wondering if someone can provide a definition and perhaps how to calculate Xd and Xq.
any other website references would work too.

Thanks

 

[Clyde38]

Sparky,
Try this:

http://www.ece.osu.edu/ems/ee743/Lectures/lect15.ppt

 

[Sparky35]

thanks, that looks like what i was looking for. I have a couple others in the dark on the topic as well, so i will invite more insight.

Thanks again Clyde

 

[aolalde]

This constants apply to salient pole synchronous machines.
Direct Axis, normally coincides whith the radial plane of symmetry of the field pole.
Quadrature axis, normally coinciding with the radial plane midway betwen adjacent poles.
Xd- Direct-axis Synchronous Reactance the ratio of fundamental A.C. armature Voltage to A.C. armature current produced by the direct-axis flux.
Xq- Quadrature-axis Synchronous Reactance the ratio of fundamental A.C. armature Voltage to A.C. armature current produced by the quadrature-axis flux.

For a specific machine; request those parameters from the manufacturer. If you want to get those by test follow the procedures by IEEE Std 115.

 

[powerjunx]

Sparky,
refer to IEEE 115-1984, "Guide and Test Procedure for Synchronous Machine Transient Parameters". There, a table of typical machine reactance and time constants were tabulated..

Also try, brief discussion on ELECTRIC MACHINERY of Stevenson, et.al.

For large Synchronous machine, try IDEAL ELECTRIC CO. for their sample TEST REPORT, you'll find all necessary parameters for your machine including time constants, all reactances,sequence reactance as well as transient and subtransient synchronous reactance,etc.

you will then see the lights out of the dark.