Electranix Corporation


Q. What versions of PSS/E .raw file formats are supported?
A. Currently, versions 23-26, 29, 30, 31, 32, 33, and 34 are supported.


Q. What versions of PSCAD are supported?
A. E-TRAN can generate three-phase Single Line Diagram (SLD) circuit .psc or .pscx files for PSCAD V4.2, and x4.6.


Q. Why doesn’t the load flow match when I run a translated circuit in PSCAD?
A. Check that the .raw file being used is “solved” and has the updated loadflow solution saved in it. Also check that fundamental frequency behaviour of any models in the E-TRAN Substitution Library match that of the standard E-TRAN components (If you turn off the Substitution Library, does the solution then match?). Finally, check DC links to see if they are operating correctly. The DC link controls may have to be adjusted to work in very weak systems (If you use the “Infinite Bus” option in the DC link component, does the loadflow then match?


Q. Electro-magnetic transients simulations require detailed data such as transformer saturation, surge arresters, line geometry for frequency dependent transmission lines etc. This data is not available in loadflow programs, so is the case generated by E-TRAN useful for EMT studies?
A. Detailed EMT models (such as transformers with saturation, frequency dependent transmission lines) are essential for any meaningful study (especially for over-voltage, harmonic studies?). E-TRAN supports a Substitution Library which allows a user to enter the detailed model data maintaining/managing the data in a PSCAD library and will automatically use the detailed data if it is available. The fundamental frequency impedances from the loadflow file are used to generate multi-port network equivalents, and, to determine the steady state powerflow. The powerflow is used to initialize all machines, sources, generators or any device. E-TRAN will automatically modify the initial condition information of machines found in the Substitution Library (which in turn will initialize any exciter, governor, multi-mass system), and in general can provide initial conditions for any device. This means E-TRAN can directly generate a circuit ready for EMT studies, complete with frequency dependent lines, detailed generator/exciter/governor models, detailed HVDC/SVC/FACTS devices etc. providing that the user has entered this data once in a library.


Q. I am measuring P and Q flow using the E-TRAN components and it does not give me the same answer as the PSCAD Master library measurements. Why?
A. The PSCAD Master library models performs RMS or instantaneous PQ measurement (for example, the sum of VA.IA + VB.IB + VC.IC etc.), which includes the effect of all sequence components and the effect of harmonics. The E-TRAN PQ measurements devices (or voltage measurements) measure the +ve sequence, fundamental frequency quantities (used in loadflow programs), not the instantaneous or RMS quantities. This effect is particularly obvious at locations where there are significant harmonics (such as near a commutating model of a DC link). If the instantaneous quantities being measured are sinusoidal, distortion free and balanced (i.e., only +ve sequence), the results should match.


Q. Where can I get technical support or updates for E-TRAN?
A. You can visit http://www.electranix.com/software or you can send e-mail to the Electranix Corporation.


Q. Where can I get technical support or updates for PSCAD?
A. You can visit http://www.PSCAD.com or you can send e-mail to the PSCAD Support team at support@PSCAD.com . PSCAD is developed and supported by the Manitoba HVDC Research Centre Inc (http://www.hvdc.ca).


Q. What E-TRAN developments and new features are you working on?
A. The E-TRAN program is always under development. Future releases will translate transient stability data in addition to the loadflow data and will form dynamic equivalents. These will include the effects of machine inertia and controls in the network equivalents. We also plan to support additional input formats (in addition to the PSS/E .raw format). If you have any ideas or suggestions for improvements to E-TRAN, please send them to us.