perolofl's profile - activity

Just a remark: In step 3) the dynamic model is added to your snapshot (.snp).

Why do you need to know the version of the saved case?

You can first do a load flow reduction of positive sequence system with EEQV. Then reduce the original network with SCEQ in order to get equivalent generators, representing the Thevenin impedance of the reduced network in all three sequences. Then insert those generators in the EEQV network.

The network prepared with SCEQ cannot be used for load flow calculations since classical fault assumptions removes the load.

Have you opened the .raw file in a text editor and checked the first line of the file? Can you open the case in PSSE?

There is nothing needed to ”finish a simulation”. You don’t need those lines. What do you want to do?

Look för large shunts and loads at same bus with opposite sign. Test to simplify by merging them together.

RAW-file: It is written on the first line of the file, at least if PSSE has written the file.

For .SAV is it not so easy. PSSE cannot open a .SAV file created by a later version. I.e. rev 33 cannot open rev 34 file but it can open files written by older PSSE-versions.

Is is just to write the write a RAW-data file of the whole converted network and read the file to create a new case. The generators will now be "unconverted".

What do you mean with "coordinates with the Winding 1 Ratio"? Does not XFRINT return what you want?

Use API xfrint.

On the other hand, it would be developing for you to add the model yourself and test different parameters in order to understand how the model works and which parameters are suitable. That is the best way to learn PSSE.

You can open the .out file with dyntools and write the channel values to .csv or an excel file using for example excelpy.

This seems to be a bug to be reported to Siemens-PTI.

How are you and your colleagues running the script inside PSSE? With "Run program automation file" or with a programmed custom button?

What do you mean? It is just to add IBUS, ’CBEST’, ID, CON(J) to CON(J+11) / to your dyre-file.

You can export to Excel in the GUI:

1. Open .out file
2. Right click the file in Plot Tree View and select "Export to Excel"
3. All channels are now written to a .xlsx file.

Unfortunately, there is no API to perform the action from python.

Have you seen and tried model CBEST?

The load characteric is described in Chapter 5.5 in Program Application Guide, Volume 1. The constant load is reduced at voltages below the value set by parameter PQBRAK (see General tab in Solution Parameters). The default value of PQBRAK is 0.7.

Please note that the figures in the manual are misleading. Figure 5-3a shows the constant load MVA characteristic when PKBRAK = 0.5, while Figure 5-3b shows the constant load current characteristic when PKBRAK is approximately 0.7. The two curves do thereby not correspond to each other.

Neither constant current nor constant impedance characteristic is used for constant MVA load load below breakpoint PQBRAK. Instead an elliptical function is used, whose details are not revealed in the manual.

What is your email address?

Pink objects means topology error, i.e. the object does not exist in the network. Solving the load flow will not help since the object is missing. Unsolved network is indicated with dimmed values.

Strange, are you using Environment Manager? I tried to compile and link and it works without problem.

Channel selection activities will add channels to the previously added channels. Execute CHSB as many times as you need...

You cannot use bus_data_3 outside PSSE to modify a saved case.

Have you declared it as external, i.e. EXTERNAL MDLIND?

The channels you choose with CHSB and the other channels selection tools are added to the snapshot. You can have up to 24000 channels in the 50000 bus version. Every time a channel is selected it will be added to the snapshot. Just try and see.

It is easy to change the value for a particular quantity. For example, to change bus base voltage for bus 151 (in case savnw):

Record a python script and perform the change manually. PSSE will write the corresponding API for the performed data change. In this case:

psspy.bus_chng_3(151,[_i,_i,_i,_i],[ 510.0,_f,_f,_f,_f,_f,_f],_s)

Here, just the base voltage is changed and all other values are, by default, not changed. The variables _i, _f and _s make so those quantities are keeping their values. In the call above only the first real argument (base voltage) is changed.

It is also possible to only specify the value to be changed. In this case it is the first value in real argument list.

psspy.bus_chng_3(151,realar1=510)

This is exactly what you are asking for!

This is an extremely basic question!

Raw data files are text files, which you can edit.

Saved cases are binary files that only PSSE can read and write.

You can always play around with savnw files in Example directory.

This is answered in Question "Monitor Branch Current in Dynamic Study"

You can use API switchedshuntdata. The control mode is integer argument number nine. The following call changes the control mode to 1 for the switched shunt at ibus.

psspy.switched_shunt_data(ibus,[_i,_i,_i,_i,_i,_i,_i,_i,1,_i])

API switchedshuntchng_3 is available in newer versions of PSSE.

A PI block should be initialised to the output signal value.

The G/(1+sT) block should be initialised to the output signal divided by G.

PSSE 33.9 allows up to 2880 wind machines while 33.4 allows only 560 wind Machines. Upgrade to a newer version!

It may be a problem with write statements in the code. Comment out those statements until you can isolate the problem and show the statement here if you need help.

Why don’t you show your code? Now, it is impossible to help you.

The value is in pu, i.e. you have to enter a value less then 1. E.g. 0.5 for 50% loading of Mbase for the generator. You have enterered 150, 300 and 200 pu!!!

Record a Python script while changing the VAR value in the GUI. VAR(L+4) is initialised to the actual load flow power at initialisation of the simulation. Changing the VAR during simulation should change the wind turbine power.

Have you tried to change VAR(L+4) in model WT3T1?

Are you writing a dynamic model? Describe better what you are doing!

Try to reduce Pgen in load flow.

It is not possible to start a generator unit during a dynamic simulation!!! All generators to be simulated must be in-service in the saved case used in the simulation so they will be initialised at start of simulation.

Synchronisation of a unit can be simulated by keeping an islanded, stand-alone AC-system with the generator bus as a swing bus and the step-up transformer switched off. The unit is then running at nominal speed until synchronisation is done by e.g. closing the step-up transformer at a proper time in the simulation.

Just be sure that the phase angle, frequence and voltage differences are sufficiently small at the instant of synchronisation.

Seems like there is an active power overload of the generator.

It is not clear if you are referring to:

1. User-defined routines for IPLAN
2. User-defined pssuserpf.py Module for RAS Simulation
3. User-written activity
4. User-written dynamic model

The easiest way is to record a python script, perform the load change manually, stop recording and investigate the API calls written to the created script.

Check for messages in Progress Window regarding status changes of buses or generators during the simulation.

Since you are new to PSSE can it be a good idea to practise with savnw case in Example directory, since it is easier for us to replicate your problems.

From where did you get the source code? What are the arguments to the delay function? Is it CON(J), VAR(L) and a local variable?

PQCONT is maybe the internal bus number of the controlled bus for the transformer.

I think DBUF01 is a character variable and the WRITE-statement is writing to the variable using the formatting in 107 FORMAT-statement.

A library model is included in the PSSE-package, while a user defined model is added with a .dll file manually after start of PSSE. The Dll-file can also be linked into dsusr.dll which is automatically read into PSSE.

A correctly written User Model behaves as a library model in the GUI, i.e. there is no difference for the PSSE user.

Mode 4-1-3-2 is called at STRT. Mode 3-2 during each time step of the simulation.

From POM: "Any error or progress report messages written in MODEs one through four should be written to the FORTRAN unit number specified by the variable LPDEV" Unit DBUF01 is unknown to me. Where do you find those statements?