YKC's profile - activity

I attempt to run the dynamic simulation cyclically, which tripping the online generators one by one, and convert the result values of output file to csv files. Then, the aim is to find the frequency nadir in each simulation case, so I would read the csv files and record the nadir value. In the testing system file, there are only 10 generators in the system. However, in the formal case, the study power grid contains hundreds of generators.

In order not to let a large number of files occupy the disk space, I would like to remove the output files and csv files after recording the nadir values. But the code I finish programming current could only remove the csv files, the output files are still in the folder. I would like to ask that do anyone have any suggestion to deal with this problem "Removing the output files"?

I use python 2.7 and PSS/E v34.4.0, and implement the code in VSCode. Also since I could not paste the entire code on the forum, if anyone want to take a look, please feel free to contact me.

YKC Email: ken890309@gmail.com / yukaichung@itri.org.tw

The important point is not the user-defined model (UDM) provided by PSS/E. Sometimes you would like to implement a function/model behavior, but unfortunately, PSS/E does not provide the model you need. Then, you can build your model by programming UDM, that is the point of significance.

For my experience, I did build the function of frequency regulation of wind turbines by UDM!!

Please take a look at the model "LCFB1" , its function is similar with AGC, but it needs to combine with governor to achieve its function.

Or you can try to build "user-defined model" of AGC.

Hi Jconto, I could not post on forum, the entire code is too long. If you willing review my code, could you please tell me your email, or you could send the mail to "yukaichung@itri.org.tw" and inform me who you are.

Hi KYC, Thank you for suggestion, I also did try using this API, and it took more time in each run. And for excel files, I will take a look. If you willing review my code, could you please tell me your email, or you could send the mail to "yukaichung@itri.org.tw" and inform me who you are.

I consider that you might directly contact Siemens PTI.

Hi Dave, Thank you for your suggestion, however, I had already added this API in my program, and it was not that useful. Still working on it.

Could you please check your "Code" of bus? Code=2 is generator bus, where Code=3 is swing bus of the system (also generator).

Code=1 is general bus, you can add the load on this type of bus.

Code=4 is isolated bus, which means that this bus can not be connected to swing bus.

Hello everyone,

I met a time issue when doing the power flow cyclically. I use python 2.7.13 (in VS Code) to control PSS/E executing the power flow process cyclically and export the overloading report. During testing, I read the csv file of branch and set each branch out-of-service in each run.The number of branch is 1790, and I set executing the process for 12 times (which means "half a day"). Thus, I expect that it will export (12*1790) overloading reports and tell me which branches out-of-service will cause other branches overloading.

Then, I find that it takes for over 18 hours to complete the entire 12 times simulation. In first run, it took around 5 mins, then second run took 7 mins, and the simulation time in each run is irregularly and extremely increasing. The followings are the simulation time in per run (min): [4.454, 6.7685, 13.7459, 25.1792, 39.6676, 59.3887, 85.0343, 112.3582, 143.5624, 178.5427, 205.1365, 219.4923]

Since each run do the same work (csv file is same to verify each run gives the same results), I could not figure out the problem during simulation: 1) why each run took different time to export the report, and 2) the time is extremely increasing? Does anyone meet this problem before? and know the reason?

I am really appreciate your help, it does solve the problem!!! Thank you for your time to answer these questions.

Thank you for answering the question, it seem can run now. However, I met another problem. I would like to change the generation of each machine, and I use "psspy.machine_chng_2" to do it, then, VSC give an error that "_i", "_f" are not defined. Do you also have any suggestion to solve this issue?

ramadhan, calculating P and Q is just product the voltage and current, you can firstly measure voltage and current and do the math.

If you still use the default model, I think it can not be changed. Re-writing REPCTA as UDM will be a good approach to solve the problem.

For my personal experience, I worked on UDM for two years, but I still could not establish gen. model. The output of gen. model is current, but API and POM did not mention about how to send the output into the network interface. But if you successes in the future , please let me know, good luck!

Hello everyone,

I want to use python in VS code to control PSS/E, but I can not import psse34 and psspy in python. Could anyone please help me solve the problem? I already try most of the python coding from this forum.

The following is my python code:

> import os, sys
> PSSE_LOCATION = r"C:\\Program Files(x86)\\PTI\\PSSE34\\PSSPY27"
> sys.path.append(PSSE_LOCATION)
> os.environ['PATH'] = os.environ['PATH'] + ';' + PSSE_LOCATION 
> 
> import psse34
> import psspy

Then, VScode gave the error as:

> import psse34   
> File "C:\\Program Files(x86)\\PTI\\PSSE34\\PSSPY27\psse34.py", line 21, in "module"
> import os, psseloc 
> ImportError: bad magic number in 'psseloc': b'\x03\xf3\r\n'

I will try it when I get the file, thank you for your suggestion. Maybe I just fuss about nothing.

I had opened the v.33 raw file and converted it to v.33 sav file when I studied M.S. But I am not sure about opening the file by two different version.

In fact, I do not have the v32 raw file currently, since we have an purchase process about purchasing file from other company. So, I asked the staff in advance, and he said that he could only offer the v.32 file.

Hello everyone,

I am not familiar with raw file and sav file.

I know that the new version of PSS/E can open the sav file in the previous version (v.34 can open v.32).

But, if I only have a raw file in v.32, can I open it by v.34 and convert it to sav file in v.34 ? And also please tell me how to do it?

Thank you!!!

Hi everyone,

I would want to write the wind turbine generator model (REGCAU1). However, I have no idea how to write the "interface to network model".

I would like to ask what are the output of REGCAU1. Since I need to calculate the model input (WIPCMD, WIQCMD, ETERM) by using the model output in MODE=1, but I am not sure which values will be already known.

Based on my experience, I can measure the correct values of ISORCE and ZSORCE, but the value of VOLT is wrong.

Thanks a lot!!!

I am a beginner of writing PSSE user-defined model, and I would want to write the wind turbine generator model (REGCAU1). However, I have no idea how to write the "interface to network model".

I have already tried to use "CURNT(IB)" in my UDM, I set "IB" to be my bus sequence number. But when I load the dll into system and run the simulation, PSSE would suddenly shut down. Moreover, when I use CURNT(actual bus number), the same situation will happen again.

When I use CURNT(), should I write any function library to load in this internal array? (like "include comon4.ins")

My PSSE is version 33.5 Oct. 16, 2013.

Thanks a lot!!!

The following is my code, which is used to measure the current on bus 40. If I change CURNT to VOLT, I can read the absolute value of voltage; but if I use CURNT, PSSE will shut down.

SUBROUTINE CONEC

INCLUDE 'COMON4.INS'

INTEGER i

INTRINSIC ABS

VAR(4000)=ABS(CURNT(40))

RETURN

END