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2019-05-21 05:21:26 -0500 answered a question How to perform transient stability for HVDC

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

2019-05-17 12:45:10 -0500 commented answer How we can check the version of *.SAV or *.RAW files ?

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

2019-05-17 12:41:34 -0500 commented answer How to perform power flow after network reduction with SCEQ?

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.

2019-05-17 00:41:19 -0500 commented answer How to perform power flow after network reduction with SCEQ?

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

2019-05-17 00:33:50 -0500 commented answer How we can check the version of *.SAV or *.RAW files ?

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?

2019-05-17 00:06:59 -0500 answered a question What is the correct way to finish a simulation

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

2019-05-13 09:19:54 -0500 commented answer How to perform power flow after network reduction with SCEQ?

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

2019-05-13 09:14:40 -0500 answered a question How we can check the version of *.SAV or *.RAW files ?

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.

2019-05-11 02:50:38 -0500 answered a question How to perform power flow after network reduction with SCEQ?

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".

2019-05-09 10:28:03 -0500 commented question API to get winding 1 ratio bus number

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

2019-05-09 01:38:18 -0500 answered a question API to get winding 1 ratio bus number

Use API xfrint.

2019-05-07 17:01:28 -0500 commented question Energy Storage In PSS/E

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.

2019-05-06 14:10:51 -0500 commented answer How to output in a readable format the monitoring in PSS/E

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

2019-05-06 09:58:40 -0500 commented question sliderPy - GetMapString doesn't work in PSSE34

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

2019-05-06 04:25:19 -0500 commented question How to import a custom Python module in PSSE?

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

2019-05-06 04:13:47 -0500 commented answer Energy Storage In PSS/E

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

2019-05-06 04:11:08 -0500 answered a question How to output in a readable format the monitoring in PSS/E

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.

2019-05-06 03:49:20 -0500 answered a question Energy Storage In PSS/E

Have you seen and tried model CBEST?

2019-05-06 03:45:44 -0500 answered a question How does psse determine the current injection for a constant power load during dynamic simulations during low voltages?

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.

2019-05-06 01:21:50 -0500 commented answer Calling API in Fortran

What is your email address?

2019-05-02 00:45:55 -0500 commented answer Pink SLD contents

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.

2019-05-02 00:41:42 -0500 commented answer Calling API in Fortran

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

2019-05-02 00:11:14 -0500 commented answer Dynamic simulation output channel

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

2019-05-02 00:06:58 -0500 commented answer How to set a custom value of the .sav file using psspy

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

2019-05-01 02:54:52 -0500 answered a question Calling API in Fortran

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

2019-04-28 17:28:57 -0500 answered a question Monitor more than one channel a time during Dynamic Simulation

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.

2019-04-26 01:04:01 -0500 answered a question Is there any way to convert a .sav to .xlxs using psspy?

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!

2019-04-25 15:08:20 -0500 answered a question the difference between *.raw and *.sav file

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.

2019-04-25 15:02:22 -0500 answered a question Dynamic simulation models including .sav,.dyr,.seq file?

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

2019-04-24 15:36:07 -0500 answered a question Dynamic simulation output channel

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

2019-04-24 15:27:16 -0500 answered a question Changing the control mode of a switched shunt

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.

2019-04-22 04:21:42 -0500 answered a question User Written model initialing

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.

2019-04-20 02:53:54 -0500 answered a question Exceed the dimensions of working memory in PSS/E V33

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

2019-04-20 00:43:03 -0500 commented answer screen message

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.

2019-04-19 00:53:17 -0500 commented answer screen message

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

2019-04-17 09:14:50 -0500 commented answer How to see the effect of wind variation on power system

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!!!

2019-04-11 11:47:29 -0500 commented answer How to see the effect of wind variation on power system

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.

2019-04-11 09:46:23 -0500 answered a question How to see the effect of wind variation on power system

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

2019-04-08 00:50:08 -0500 commented question screen message

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

2019-04-04 01:24:36 -0500 commented answer wrong initialization

Try to reduce Pgen in load flow.

2019-04-03 08:47:35 -0500 answered a question black start in PSS/E

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.

2019-04-03 01:40:40 -0500 answered a question wrong initialization

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

2019-04-03 01:38:40 -0500 answered a question user-defined

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
2019-04-03 01:12:08 -0500 answered a question How to modify an existing case data?

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.

2019-04-03 01:06:42 -0500 answered a question Equipment not in service after dynamics simulation

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.

2019-03-25 16:37:30 -0500 answered a question can someone explain to me how the DELAY function works on PSS E model writing?

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.

2019-03-25 16:17:03 -0500 commented answer model writing and debugging

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

2019-03-24 01:24:55 -0500 answered a question Question about user models of Library and of users models in PSSE

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.

2019-03-22 11:21:41 -0500 commented answer model writing and debugging

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

2019-03-22 11:20:48 -0500 commented answer model writing and debugging

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?