Science topic

Power Systems Simulation - Science topic

Explore the latest questions and answers in Power Systems Simulation, and find Power Systems Simulation experts.
Questions related to Power Systems Simulation
  • asked a question related to Power Systems Simulation
Question
8 answers
I'm looking for Matlab code for optimal capacitor placement/sizing using genetic algorithm.
Relevant answer
Answer
  • asked a question related to Power Systems Simulation
Question
6 answers
Comes under power system's Transient stability studies
CCT=Critical Clearing Time,
PSAT=Power System Analysis Toolbox,
TD=Time Domain simulation
Relevant answer
Answer
It is difficult to calculate CCT by using the manual computing for large power system.
The easy way to find it from the time domain simulation of rotor angle. Assume the inital value and repeat the process gradually until the rotor angle diverges from a stable value. The maximum clearing time which keep the stability is the CCT.
Another method was discussed in
10.1016/j.seta.2016.05.007
PSS/E generates file function to repeat the process automatically.
  • asked a question related to Power Systems Simulation
Question
10 answers
Colleagues, good afternoon! I was wondering what problem is the most urgent at the moment in the operation, design of gas turbines and combined cycle plants. Influence of gas turbines on the steam circuit, power reduction during summer power limitations. maybe the quality of fuel and self-contained liquids?volume_upcontent_copysharestar_border
  • asked a question related to Power Systems Simulation
Question
5 answers
I have done a PSS kundour Model using PSAT software and I want to find PSS's parameters using partrical swarm optimization. I done the partical swarm code but I want to know how to insert the PSAT model in partical swarm to find  PSS parameters?
Relevant answer
Answer
Sir can u please share kundur two area test system using PSAT.
  • asked a question related to Power Systems Simulation
Question
3 answers
I want to to generate the power trace input file for HotSpot.
I am using Wattch power simulator. Wattch doesn't generate the power trace for directly.
can any one help me what changes required in wattch source code to generate ptrace file
Relevant answer
Answer
Hello Bala,
I am trying to generate the power trace file through Noxim. Can you please let me know whether you figured out the answer as to how or not.
I have the power by each FU in each cycle.
Thanks in advance.
  • asked a question related to Power Systems Simulation
Question
5 answers
Especially for the non-condenser bushing. I'm studying FEM analysis.
Relevant answer
Answer
Material type
Climate
Rated voltage levels
.
  • asked a question related to Power Systems Simulation
Question
28 answers
.
Relevant answer
Answer
For more details ,we have these articles:
1- Optimal distributed generation allocation in distribution systems for loss minimization
Authors Karar Mahmoud, Naoto Yorino, Abdella Ahmed
2- Advanced Pareto Front Non-Dominated Sorting Multi-Objective Particle Swarm Optimization for Optimal Placement and Sizing of Distributed Generation
DOI: 10.3390/en9120982
  • asked a question related to Power Systems Simulation
Question
5 answers
I want to simulate nonlinear state space equations, I need it for stability analysis.
Relevant answer
Answer
See these articles:
1-Nonlinear dynamic analysis of a single-machine infinite-bus power system
Article Nonlinear dynamic analysis of a single-machine infinite-bus ... 2- PSDAT: Power System Dynamic Analysis Toolbox
Code PSDAT: Power System Dynamic Analysis Toolbox
Best regards
  • asked a question related to Power Systems Simulation
Question
22 answers
In addition to Simpower.
Relevant answer
Answer
See these articles:
1-Nonlinear dynamic analysis of a single-machine infinite-bus power system
2- PSDAT: Power System Dynamic Analysis Toolbox
Best regards
  • asked a question related to Power Systems Simulation
Question
6 answers
So I have MVAsc rating given of an 132 KV grid which is connected to bus. The cable impedances are also given. The total load consumed is also given. How can I model 132 KV grid in PSSE? Can I do it with an equivalent generator? If yes how to estimate its capacity
Relevant answer
Answer
I am an expert using PSS/E but I did not understand your question well.
If you mean how to make an equivalent for a 132kV grid, this done by using an equivalent load and generator as well!
  • asked a question related to Power Systems Simulation
Question
6 answers
I am working in the area of DC Microgrid in this regards I need a DC-DC converter. I will be thankful for this act of kindness.  
Relevant answer
Answer
Data Current Controlled Voltage Source Inverter (CCVSI) Simulation and Design using Simulink (in Persian)
regarding
  • asked a question related to Power Systems Simulation
Question
3 answers
Does Etap or CYME power system simulation software provide Y-Bus matrix display like PowerWorld?
Relevant answer
Answer
I did not find yous in etap
  • asked a question related to Power Systems Simulation
Question
3 answers
Can anyone share the PSS/E (Power System Simulation for Engineering) user manual?
Relevant answer
Answer
Hi! please see the attached file below in V30.
  • asked a question related to Power Systems Simulation
Question
3 answers
Is it possible to simulate a line outage by simply removing a certain branch from the branch matrix of Matpower? What about the isolated bus resulting from the line outage? I tried simulating a line outage in Matpower by simply removing a branch from the branch matrix of Matpower and the load flow still converges.
Relevant answer
Answer
You don't need to remove the row. you can, it wouldn't cause an error, but you don't need to.
One of the columns in the mpc.branch matrix is a "status". if it was "1" then it means the line is connected (on). if you change it to "0" it means the line is disconnected (off).
check the MATPOWER manual.
  • asked a question related to Power Systems Simulation
Question
8 answers
Is there any code / package / script to automatically generate single-line diagrams from PYPOWER/MATPOWER casefile or IEEE CDF formats?
Relevant answer
Answer
Matlab now has a toolbox for graph theory and complex networks.
i used that toolbox to convert MATPOWER data to a graph, and then generate a plot.
it was useful for me when i wanted to visualize different distribution networks i was working on.
keep in mind that distribution networks don't have loops. so the graphs were pretty neat. but for a large meshed system, the graph would look ugly. matlab wouldn't go out of its way to make a neat graph (with no lines crossing).
the code i wrote throws different kinds of errors everytime i run it, and everytime i debug it or do something to fix that particular problem.
if you're a matlab expert/novahoo, i can share that code with you. you're going to need to look under the cover and debug an error when you get one
otherwise, wouldn't recommend it
you can write your own code. the key matlab commands are:
buidl a graph with:
my_graph = digraph(......)
or
my_graph = graph(.....)
and then
plot(my_graph);
in my code, i tried to color code the different nodes, and represent the impedance or flow size on a transmission line by the line's thickness
  • asked a question related to Power Systems Simulation
Question
11 answers
how can the results be validated for a power system simulation?
Relevant answer
Answer
Dear Umair,
Verification can be done by using another tool to make the calculations when the results agree then your calculations were done correctly.
In order to validate your results you have at first to solve a known system.
The ultimate method is the building the system and measuring its performance parameter or simulating an already measured system.
Best wishes
  • asked a question related to Power Systems Simulation
Question
1 answer
Actually I'm trying to generate wind direction and velocity using sentinel
1 images.
But I'm having some problems.
After processing the imaging, using Sentinel 1 toolbox (SNAP), we have been
obtained this kind of image (see file attached). In this image appears
wind direction (with ambiguity) and velocity in m/s.
Where I tried to export these parameters those that are exported are in
the .txt file attached.
My questions is: 1 - How to extract the wind velocity from these image and
export it in as made in .txt file attached ?
2 - How eliminate the ambiguity in order to obtain the
wind direction?
Do you know anybody that is working in these theme using sentinel 1 data
in order to help me.
With my best regards,
geraldo
Relevant answer
Answer
Hello, try to save the txt file as excel format.
  • asked a question related to Power Systems Simulation
Question
5 answers
Hello All,
I am working on HVDC VSC converters in DIgSILENT power factory. I have developed the grid and the DSL models of generators, controls and the VSC converters. But, when I run the simulation, it says something on inner-loop iteration reached for some models. I want to know how to resolve this error in DIgSILENT power factory. I have asked this question in the customer portal, but it didn't help me much. They suggested me what I already knew and have tried. I can send the pfd file if required.
I appreciate your help.
Thank You
Anand Prakasha
Relevant answer
Answer
Hi Im tuning 4 VSC stations for a HVDC grid, modulus optimum and symmetrical optimum. works????
  • asked a question related to Power Systems Simulation
Question
3 answers
What is the process to carry out power simulation of any benchmark program using McPat simulator. How to get counter values need to be configured in xml file which is needs to be provided as input to simulator and how to get ptrace fie as output.
Relevant answer
Answer
You can use some architectural simulator like gem5 and to get counter values from there.
  • asked a question related to Power Systems Simulation
Question
4 answers
I have done a theoretical analysis to find out the rating power that need to be produced from PV panels depends on the datasheet given below at 7222W.
I have calculated the sizing design of PV arrays for 4 panels connected in series and 7 in parallel to get total at 28 panels at rate 120V and 60A that need to meet the demand.
Note Xsys=0.09 ohm at 25KA current fault level from IET datasheet.
the issue is how to implement this demand of power from the PV using matalb codes or simulink by demonstrates parallel and series connection of solar panels to get the rate at 120V and 60A?
the attached files shows schmatic of proposed system
Regards
Relevant answer
Answer
Did you completed the series parallel connection in simulink?
  • asked a question related to Power Systems Simulation
Question
4 answers
The list of simulation software is available at
Please visit the corresponding website if you do not understand Russian.
Relevant answer
Answer
The list will be helpful, especially if they are categorized by the type and application. If there is an overarching organization for simulation software (government or commercial), a link to that organization or main points of contact can be useful.
  • asked a question related to Power Systems Simulation
Question
7 answers
Dear all ;
Am working on MINLP to minimize the total power losses of the network.
All the used equations were typed correctly.But when i run the GAMS code it gives this error : Infeasible solution. Reduced gradient less than tolerance?
I need assistance in that error ?
Best Regards.
Amna
Relevant answer
Answer
  • Try to solve your model with a different NLP solver
  • Try to solve it with a global solver. This may give an indication whether feasible points exist at all.
  • Provide a better starting point. The default starting values of zero are often not appropriate.
  • Provide better bounds and look at the scaling of the model.
  • Try to solve some smaller instances of the model.
  • asked a question related to Power Systems Simulation
Question
5 answers
I would like to try the use of the SciLab (https://www.scilab.org/) in the simulation of electric power networks, and systems. Based on your experience, is it a worth for the use in the mentioned application? Please compare with alternatives, such as the MATLAB.
Relevant answer
Answer
As you probably noticed, Scilab has very similar syntax to MATLAB, but still not the same. Some things, such as inline function definitions and fixed variables (%pi) are even tidier in Scilab in my opinion. Regarding plots I never had issues. In my opinion, the biggest downside is that Scilab has way less toolboxes than MATLAB. Historically it was also way slower, but that has improved by now.
I would recommend you to take a look at Python. It has a lot of momentum and is becoming more popular than both packages. With IDE Spyder you will get similar environment to Matlab or Scilab, with integrated figures and variable lists. It has plenty of libraries for numerical computing, such as SciPy, NumPy, Pandas etc... To sum up, there is also PyPsa library that is used for power systems simulation.
  • asked a question related to Power Systems Simulation
Question
8 answers
coil wound alternators are used everywhere to Generate electric power in all  kind generating stations.Though it is demonstrated by vande graf (static generator)  it is is not popular  in power generation. Let me know the limitations and constraints if any
Relevant answer
Answer
Some of the answers posted here so far have, I think, rather missed the point; but then, so did the question. The salient point is that the 'opposite' of 'magnetic' is not 'electrostatic' but simply 'electric'. Forget the term 'electrostatic', as that is just misleading. Conventional so-called electrostatic generators are designed to generate high voltages (for 'static electricity') rather than power. If we want to generate power then we simply look to the electric analogue of a magnetic power generator. As I will demonstrate, electric machines are theoretically much better at generating power than magnetic machines; but there are good reasons why they have not caught on.
Consider, first, how a generator works using magnetic induction. A moving magnet (relatively speaking) causes a time-varying magnetic field which generates a voltage in a loop of wire. If you complete the circuit to allow a current to flow, you dissipate energy and this arises because of the energy required to move the magnet against the field induced in the loop. A magnet is manufactured by allowing a material to 'solidify' in an area of high magnetic flux, so that the magnetic domains are 'frozen' in place.
A magnet is, more formally, a ferromagnetic material. Now consider the electric equivalent of a magnet, which is a ferro-electric material, also known as an electret.
A moving electret causes a time-varying electric field which generates a current in a wire/plate. If you complete the circuit to allow a potential to build up, you dissipate energy and this arises because of the energy required to move the electret against the field induced in the wire/plate. An electret is manufactured by allowing a material to 'solidify' in an area of high electric flux, so that the electric domains are 'frozen' in place.
The analogy is interesting, yes?!
Although 'magnetic induction' is the more familiar phenomenon, you will probably have done physics experiments at school with 'electric induction' using an electrophorus, which is a device for transferring electric charge from a reservoir. One of the key points in those physics lessons was to get the pupil to explain why it apparently allows you to transfer charge indefinitely, i.e. where does all the charge come from? That’s a very clever question, and it baffles most students, but it is only like asking why a magnet lasts 'for ever'.
Now, the energy storage density of a magnet is simply ½ B.H which, for a NdFeB magnet with a relative permeability of about 1 and a saturation flux density of (say) 1.3 T [Tesla, equal to As/m^2], gives about 0.8 MJ/m^3. The energy storage density of an electret is, similarly, ½ D.E which, for barium titanate, with a relative permeability of about 200 and a saturation flux density of 0.16 Vs/m^2 [that unit has no common name, unlike the magnetic analogy], gives about 7 MJ/m^3.
So you can see that – contrary to what others have said - an electric generator could be ten times better than a magnetic generator for the same volume of active material. So why do we not use electric generators?
Well, of course, they are used. For very small devices (not necessarily "nano" but just "micro" or "milli" devices) they work much better than a magnetic generator because they do not require a bulky copper coil to be added to the assembly.
However, for larger devices there are a number of engineering reasons why they are not used. To achieve the theoretical maximum flux density in an electret requires a very high electric field strength and, due to the breakdown voltage of the material, this limits it to a thickness of perhaps 1mm - so large devices are not practical. There are several other reasons, including those of cost, and of 'historical investment' by which I mean that there is a large body of knowledge on magnetic generators and no real incentive to find an alternative – except for specialised and very small devices.
Hope this helps!
  • asked a question related to Power Systems Simulation
Question
7 answers
Hi,
I am trying to model a system in PSS/e for transient stability studies. The network I am trying to model has a total demand of 1300 MW during peak season and it is interconnected to two other countries which have total capacity of 10 GW and 2 GW. I've short circuit MVA for the two interconnections, using which I've calculated the Zsource of the machines.
I've two questions:
1. Would I be using the short circuit MVA to represent the machine base or total capacity of the each machine for the studies?
2. Which generator and governor model to use to represent the inter-connection? Also, what would be the inertia (H) of the machine for transient stability studies?
Thanks for the help.
Relevant answer
Answer
Nitish
1. It's an infinite bus, so frequency changes don't come into it. Hence I don't think you need to model the infinite bus source with governor droop (sorry Arun).
2. I'm with M. Lima: a GENCLS synch machine model with H=0 is the best & simplest representation to an InfBus source.
3. A useful equivalent system model for the scenario you describe connects the InfBus source to the test network via 2 (or more) circuits with impedance chosen to reflect the pre- and post-fault infeed MVA. Then a fault on one, cleared by tripping it, simulates the change in post-fault conditions.
4. It doesn't matter what base MVA you choose (except to change the numeric values). Pu on test network base is OK, just so long as you make the connecting circuit X pu on the same base
  • asked a question related to Power Systems Simulation
Question
12 answers
This parameter is used for recognition of islanded networks.
Relevant answer
Answer
For islanding detection, sometimes RMS rate of change of voltage is used. We have used in one of our publications.
  • asked a question related to Power Systems Simulation
Question
6 answers
Dear All
Does anyone know and can sent me a link for free software which can be used for thermal analysis of cable - ampacity and temperature computation around the cables in different environment (ground, water, air, concrete pipe.) I know that there are many commercial software from CDEGS, EATON-CYME..... but I need easy free software to eliminate manual computation.
Thanks in advance
Relevant answer
Answer
We did a manual calculation in air before in
  • asked a question related to Power Systems Simulation
Question
9 answers
I am trying to build a model for kundur two area system and do small signal stability analysis in simpowersystem .The state variables in simpowersystem are different from the kundur as simpwer system takes state as curent of inductor and capacitors.  Any idea how to build state space as in kundur  would be greatly appreciated
Relevant answer
Answer
In the mentioned problem. tools such as the Power System Toolbox (PST), or the Power System Analysis Toolbox (PSAT) are more easier than the SimPowerSystems toolbox for an elaborated small-signal stability analysis. In addition, they are open source tools i.e. you can modify their liberary models, and add new models.
  • asked a question related to Power Systems Simulation
Question
9 answers
MATLAB, ETAP, DIGSILENT OR PSCAD
Relevant answer
Answer
EMTP, DIGSILENT and MATLAB/Simulink on performance basis.
It is workable to create required Model in EMTP and MATLAB /Simulink, if you have compact knowledge.
Analysis is Superior in EMTP.
Help is available at Math-works in case of MATLAB /Simulink.
DIGSILENT is more professional tool and gives more credibility to your results on tool's end.
So kindly find out a trade-off according to your needs, circumstances and available tools/facilities.
  • asked a question related to Power Systems Simulation
Question
8 answers
I am working on partitioning problem and want to show a novel algorithm for network partitioning based on complex network theory. I need this system high quality figure. I don`t have access to this figure.  Any advice? Can anyone send me this figure?
Relevant answer
Answer
  • asked a question related to Power Systems Simulation
Question
5 answers
Hello;
I want to determine the interconnection damping and inertia constants for a real power system. If the detailed simulation of a power system exists in the power system simulation software such as DigSILENT, it can be useful to obtain these constants?
Thank You
Relevant answer
Answer
Kindly check, whether something from the following paper would be helpful to you.
Athbel Joe, and S. Krishna, "An Underfrequency Load Shedding Scheme with Minimal Knowledge of System Parameters," International Journal of Emerging Electric Power Systems, vol. 16, no.1, pp 33-46, Feb. 2015. (doi:10.1515/ijeeps-2014-0108)
  • asked a question related to Power Systems Simulation
Question
6 answers
My project is to optimize the location of statcom to improve the voltage stability in a given system data using genetic algorithm.First i did a nrlf and later manually optimized the bus at which voltage is below rated value by integrating statcom into nrlf at that particular bus.Now i am trying to optimize it using genetic algorithm.Iam trying to use the 'optimtool' present in matlab to do this.For this i need to write the fitness function.I have a little idea on how to do it (as i am trying to maintain voltage stable then minimizing the deviation in it should come under the fitness function) but i am unable to relaize how to write it.So i would love it if any one can help me with this issue.Thank you in advance
Relevant answer
Answer
Kishore you can use some voltage stability index as your fitness function. Thus you can use the system parameter  and the nrpf  solution in your code.
  • asked a question related to Power Systems Simulation
Question
1 answer
How can we get the load cost vector? The elements of this vector represent the independent load values or costs of the corresponding bus. The unit of the cost is $/kW or $/MW
Relevant answer
Answer
The load price depends on ISO that is supplying the area in question. So, you can find the data on their sites. For PJM for instance, the site is:http://www.pjm.com/markets-and-operations/energy.aspx
and you can find nodal prices vectors.
  • asked a question related to Power Systems Simulation
Question
4 answers
We have some electrical data like line length,R/X ratio of lines,P and Q of loads on GIS software for a real distribution network.
How can i use these data in Digsilent?
Relevant answer
Answer
Yes, DIgSILENT PowerFactory has the DGS, it is the abbreviation for “DIgSILENT Interface for Geographical Information Systems”.DGS (DIgSILENT) is PowerFactory’s standard bi-directional interface specifically designed for bulk data exchange with other applications such as GIS and SCADA, and, for example, for exporting calculation
results to produce Crystal Reports, or to interchange data with any other software package. See more details on Chapter 22, Interfaces a the PowerFactory User's manual. Regards FGL
  • asked a question related to Power Systems Simulation
Question
6 answers
Actually I work on the problem of optimization of a microgrid, the optimization should take into consideration the whole power flows in the power system to satisfy the power balance with respect to conversion efficiency and all other imposed constraints.
So I have a lot of equations and formulations, then I wish to know the best method to simulate and to test this system?
- What's the best solver based on C++ or Java library that I can use it inside simulink model using block or s-function to optimise the powers flow by mixed integer linear programming of my power system and the way to do it?
I notice that I have a sumilink model of the power system simulated using real component of Matlab library, I mean for example to simulate PV arrays I used real component not formulations, so it's possible to use this solver embedded in simulink model to get results?
Finally, I searched a lot of a solver that I can call it easily in matlab simulink and use it inside a s-function using C++ code and also the best way to simulate this system directly in the simulink model without using command line because that make the system very hard regarding that the documentation and sources are very rare?
Please I don't ask for publications with the same problems because I lost a lot of time so I look for a direct sources and solutions?
Thanks.
Relevant answer
Answer
Hello Nabil,
To avoid any misleading answers, I would represent the problem at first.  
I understand your problem as following, you have made dynamic simulation (against time). For each step of time you have load-flow (or circuit analysis).  Now, you need to optimize the system parameters like injected power or even switching. In that case you have to go in one of two ways. First, you have statistical data and go for optimal solution expected. Second, solve the system several times for optimal operation, using some evolutionary algorithm like genetics.
In both cases you need to make the optimization technique first, then embed your system as a block not the opposite.
If my understanding is correct, kindly let me know that may lead to some steps forward.    
  • asked a question related to Power Systems Simulation
Question
3 answers
I am working with rotor angle stability analysis based on matlab program. I need to validate my program with datas obtained from transient stability analysis done in ieee bus system developed in etap. How could i do it
Relevant answer
Answer
Dear Athira,
refer to the follwoing link:
  • asked a question related to Power Systems Simulation
Question
5 answers
Literature says the data is available in "P. M. Anderson and A. A. Fouad, Power System Control and Stability" (Revised Printing). New York: IEEE Press, 1994. Can someone provide me this data?
Relevant answer
  • asked a question related to Power Systems Simulation
Question
6 answers
I am working on grid vulnerability analysis and I need to run power flow for a grid with high penetration of wind generation. I was wondering what is the most convenient way of modeling wind farms. Can I model them as PQ buses with negative P (negative load)?
Relevant answer
Answer
Most modern wind generation technologies have voltage control capability, so these are not PQ buses in power flow analysis. You should represent them as PV buses. Now, depending on the technology, the reactive capability limits might be different. 
Also, note that often the voltage control is implemented as a wind plant centralized control, that controls the setpoints of the individual wind generators to meet voltage control requirements at the point of interconnection. Having said that, it is significantly more difficult to represent a wind plant (dozens or hundreds of individual units) in great details without also, somehow, representing this centralized voltage control. 
The PV bus approach would work reasonably well for the aggregate response of the wind plant, as seen from the point of interconnection,  though. 
  • asked a question related to Power Systems Simulation
Question
3 answers
Solution should be based on a steady state network using nodal voltage method.
Thank you.
Relevant answer
Answer
1- THE EFFECTS OF POWER SYSTEM HARMONICS ON POWER SYSTEM EQUIPMENT AND LOADS, IEEE Transactions on Power Apparatus and Systems, Vol. PAS-104, No. 9, September 1985.
2- Understanding Power System Harmonics, Grady/Santoso, September 1, 2001
  • asked a question related to Power Systems Simulation
Question
7 answers
How does PSO represent FACTS bus number and its sizing. Is it possible to embede PSO matlab codes with PSAT power flow rountine?
  • asked a question related to Power Systems Simulation
Question
1 answer
An example of this approach was seen in T-MAC, but i could not find any recent. I am actually interested to send block acknowledgements for multiple concatenated packets sent by a node. even the packet concatenation schemes do not describe the acknowledgement mechanism followed. Suggestions Please!
Relevant answer
Answer
use the same example as it is very effective for your problem.
  • asked a question related to Power Systems Simulation
Question
2 answers
An example PSS/E .raw file can include the following data: Bus Data, Load Data, Fixed Shunt Data, Generator Data, Branch Data, Transformer Data (2 winding / 3 winding), Area Data, Two-Terminal DC Data, Zone Data, Owner Data and Switched Shunt Data. Having these data in the PSS/E file, Can anyone get me the corresponding data representation in CIM RDF XML file?
Relevant answer
Answer
It is a PSS/E power system simulation software developed by Siemens.
  • asked a question related to Power Systems Simulation
Question
38 answers
How ca n I draw a curved of receiving-end voltage magnitude as a function of load?
10-2- Please see the attached files.
Relevant answer
Answer
hi
please  see  the   attached  file
  • asked a question related to Power Systems Simulation
Question
2 answers
In high power transmission line are there any protocol called IEEE look like in network system ?
Relevant answer
Answer
thanks Mr Jesús Rodríguez-Molina
  • asked a question related to Power Systems Simulation
Question
2 answers
Hello All,
I spent all morning searching for the error solution on google, so Mathworks and here. I attempted every potential solution I could find: delays, solver changes, saturation, tolerance. I attached the Simulink Power Systems model I have for the verification of my masters research.
While I noticed it originally I dismissed it as I thought Simulink was programmed better with the initial value set, I have narrowed the error down to the voltage measurement origination from the battery model, both the internal and external voltmeter. 
Does anyone on here have any idea what settings are required to circumvent this simulation error? Thanks in advance.
Relevant answer
Answer
a) the error traces back to the battery control subsystem, from the battery voltage measurement, and nothing to do with the super-cap yet at least. 
b) checking my super-cap block I have no parallel capacitors.
c) I did change the solver from ode23tb which I used successfully for the equivalent simscape model. It was throwing that error for that as well
c) both with my prior equivalent simscape, and through my research having a power gui block within each subsystem is allowed. 
  • asked a question related to Power Systems Simulation
Question
6 answers
I was doing research on capacity credits of renewable energies. I am looking for databases that might contain High resolution data with hourly/daily for Loss of load probabilities and other metrics that are helpful to calculate capacity credits about a farm?
Relevant answer
Answer
Hi Hitesh,
Your answer will depend on the region you are and the electricity operator (ISO) for that specific region. Let's say for Berlin you have to find who is the regulatory body that manages the electricity market and transmission lines. They have a database of all available generation sources and their respected capacities and in most cases they will grant access to that database. 
Cheers!
  • asked a question related to Power Systems Simulation
Question
1 answer
I have the paper which I have attached herewith.No matter whether the model is in simulink, labview, etap or any other software.Thanks in advance.
Relevant answer
Answer
Accurate simulation file papers  not shared with others generally.
You can also use MATLAB and promote ready examples , to achieve the simulation.
  • asked a question related to Power Systems Simulation
Question
13 answers
The tools should be able to simulate the transient process after disturbances. Besides, it can also simulate the long-term variation of the power load.
Relevant answer
Answer
You can use DIgSILENT educational low cost  version with 50 buses! Fabio give you a paper with model. Model use one dimensional vector fro P and Q versus time.
  • asked a question related to Power Systems Simulation
Question
12 answers
Hi respected fellows, I am working on ring connected distribution system, My question is how can I isolate the faulty portion from the remaining network so, that it will not interrupt the supply to other part. Up till  now when I put fault in the system it will shut down the whole system. 
  • asked a question related to Power Systems Simulation
Question
3 answers
i want to regenerate behaviour of constant PQ-loads from Fig.5.a from chapter-2 of this book(Wind Farm – Impact in Power System and Alternatives to Improve the Integration);Despite much effort i cant regenerate that.please guid me.
Relevant answer
Answer
Zahir,
Just as a clarification, what do you imply by "regenerate" ? 
-Sanjay
  • asked a question related to Power Systems Simulation
Question
4 answers
I want to analyse the integrated power system (having solar as one of the source of power ) using transient simulation software (PSCAD). Is it worth to use the same or should i use different software ? 
Relevant answer
Answer
Akhilesh,
If you wish to simulate the growth of oscillations as in time domain waveforms then PSCAD/EMTDC can help adequately.
But since you wish to do small-signal stability, you may need stuff like eigenvalue based analysis and design, or participation vectors - stuff for which you may need other software.
-Sanjay
  • asked a question related to Power Systems Simulation
Question
3 answers
I am working on resistive switching based memory devices. In my devices, I get off current in the range of 1E-5-1E-4 which is very high. It deteriorates the Ion/Ioff and the hence the device performance. For a memory device, the Ion/Ioff ratio is very important factor. Please suggest me how can I reduce the off current. I research papers I have seen off currents of upto 1E-9.
Relevant answer
Answer
Ishan ,Acording to my perception..... by using stack insulators you can increase leakage resistance and will get required current e.g. metal -insulator 1-insultaor 2 - metal 
  • asked a question related to Power Systems Simulation
Question
10 answers
Recently, I have been using MATLAB to simulate a hybrid renewable energy system (Wind and GCPV plant). Is there any reliable, fast and powerful software that could be used to simulate power systems! DC link power levels! AC/DC Sides of hybrid renewable energy systems!
Cheers.
Relevant answer
Answer
As I vote on the first answer DIgSILENT PowerFactory !!!
Srete
  • asked a question related to Power Systems Simulation
Question
3 answers
Actually, there are a model of a turbine in Prabha Kundur book´s only with the effect of the injector but I need a model with the effect of the deflector, too. I have to simulate the turbine in POWERFACTORY of DIgSILENT.
Relevant answer
Answer
Can you be more specific . Since you deal with turbine do you think of governor regulator. What is injector and deflector?
Srete
  • asked a question related to Power Systems Simulation
Question
2 answers
Hi everyone,
I am trying to create some simple user defined models (UDM) in psat. I am using psat 2.1.9 and tried to create UDM from component browser in PSAT GUI. However, I am unable to define anything like buse or state variable on a new model. I then tried to modify the existing examples and still was unable to do it. 
Can anyone help me with it?
Cheers
Sam
Relevant answer
Answer
Hello Sam
You can go through this material, may b it will help to modify the state variables...
  • asked a question related to Power Systems Simulation
Question
4 answers
Hello: 
I am getting mixed results for the power conversion efficiency measurements in my undergraduate research despite this being a routine procedure, so I would greatly appreciate feedback on the process and calculations I am using.
1) I apply a voltage (mV) in parallel with the solar cell while measuring the current response (mA) using a Wavetech multimeter in series with the cell. This is done for both forward and reverse bias (from -900mV to 900 mV). The cell is illuminated by a solar simulator at 1 Sun (1 000 000 mW/m2) intensity. 
2) I calculate power (mW) at each voltage by P = I(mA) * V(mV) and select the highest value in the 1st quadrant (Pmax).
3) I calculate power conversion efficiency as follows:
PCE (%) = (100% * Pmax)/(1 000 000 mW/m2 * cell active area (m2)
Attached is a cartoon of the circuit I'm using. 
Thank you for you patience. 
Relevant answer
Answer
The most important thing is that your power supply is a voltage source, in the sense it must have a small internal resistance other wise you have to use a voltmeter to measure its voltage or better you measure the directly the voltage on the solar cell.
If you display your I-V curve one can easily judge the correctness of the measurement.
Otherwise every thing is okay.
Best wsihes
  • asked a question related to Power Systems Simulation
Question
2 answers
Hi,
I am simulating (by simulink) a distribution network feeder which consists of PV generation site and load. my simulation is too long at time domain so it requires a phasor simulation type (in the configuration parameter of the powergui). However, some of the elements in the model require a discrete simulation type. Running the simulation for the feeder model using a phasor simulation type gave me an error.
May I know how do I go about solving this problem? Any help or advice would really be greatly appreciated!
Relevant answer
Answer
thank you Samundra Gurung 
  • asked a question related to Power Systems Simulation
Question
2 answers
Hello,
I am simulating a case of vanadium redox flow batteries with carbon felts of thickness3.8mm at 50 percent SOC.Now I am getting an overpotential across the thickness of negative electrode which increases near the membrane.Can anyone explain why this scenario happens?
Relevant answer
Answer
Should be potential changes near the membrane, reflecting the kinetic barrier for ions to enter/exist the membrane.
  • asked a question related to Power Systems Simulation
Question
7 answers
I am simulating sensorless control of PMSM. I am giving constant theta at the starting time but my motor is not starting, what could be possible reasons?
  • asked a question related to Power Systems Simulation
Question
3 answers
For a industry research project we can get distribution grid models which they have modeled in PowerFactory. We would like to work with the models in OpenDSS and Matlab and of course would like to spare remodeling the grids in the software. I can't find anything online to achieve this.
Has anybody achieved exporting from PowerFactory to OpenDSS? Maybe even a self written script to achieve this which he/she is willing to share?
Kind regards,
Marcus
Relevant answer
Answer
Develop a logic which can import data from .xls file to matlab then fed them into OpenDSS through DSSText.Command using COM interfacing.
Another platform to discuss this issue (follow the link) https://sourceforge.net/p/electricdss/discussion/861976/
  • asked a question related to Power Systems Simulation
Question
1 answer
I am trying to catch the electrolyser, storage and compressor cost even from quote but for a bit large case and also if I move from size to bigger  size how I can scale the cost based on the big size?
Relevant answer
Answer
maybe i can help you but need more explanation what you want exactly!
  • asked a question related to Power Systems Simulation
Question
6 answers
Hello,
This question pertains to Matlab simulation. I will be grateful in case anyone knows the answer.
Attached .docx file is a Simulink circuit of a inverter simulation. In order to implement close loop control of inverter, I first make it work as rectifier and trying to do its PLL and current control loop implementation. In this quest, I am applying a voltage through a grid and modify it to another level by transformer. I am not able to figure out that after putting any Kp and Ki values, why does the input current waveform shape is not symmetrical? Can any one help me to find the problem? In another file, I have attached Voltage (Upper) and current (Down) waveform taken from grid. The corresponding scope is marked in .docx file.
Regards
Aalok
Relevant answer
Answer
Try using Yn instead Yg on the transformer and connect the source N and the transformer N together.
  • asked a question related to Power Systems Simulation
Question
4 answers
Hello everyone. I'm designing a 5-level diode-clamped inverter and I have met the following issue: as time passes (0 to 0.5 second simulation) I find a crossover distortion in the output sine wave (filtered) that can be mitigated by increasing the DC capacitors (those which divide the Vdc input into Vdc/2).
To prove this, I have simulated the inverter replacing these capacitors with ideal DC sources (Vdc/2 rated each one) and the crossover distortion dissapears.
As far as I understand, this means that I should have large capacitors in my real circuit, the question is: how to calculate them analytically?
Relevant answer
Answer
Hello Marc and Sanjoy. I've found out the origin of my problem: deficient energy recovery path for the "lower capacitors". It produced a gradual discharge and unbalance in the voltage levels. That's why the system worked when I tested it with DC sources: they don't discharge. 
I solved the problem revising the diagrams. All working well now.
My advice: Don't trust much those "multilevel inverter topologies with reduced swiches", they hide several drawbacks.
Thank you for your cooperation!
  • asked a question related to Power Systems Simulation
Question
8 answers
First, all the input variables of function are in the workspace. Then, I enter the function in the command window like this and I can get the results:
However, directly running in the m file  , that will cause a fault:
So, what's wrong and how can I run the m file correctly?
Relevant answer
Answer
You need to create a new .m file with the content [D,h, c] = LENnumeric( q, qd, qdd, Baxter_l ). If all the required variables are in the workspace, it should run. You cannot run the file LENnumeric directly from the editor. Since it is a function you have to pass the required variables to it (even if they do exist in the workspace).
  • asked a question related to Power Systems Simulation
Question
4 answers
For our project, we need to explore the possibility of developing functional blocks for load flow, load forecasting, optimal power flow, etc. in Simulink, without using Matlab code so that the functions can be easily converted as function blocks to hardware using other software. Is it feasible? 
Relevant answer
Answer
Simulink blocks use programs to give their output. Load flow calculation, load forecasting, and optimal power flow certainly a very complex phenomenon which is difficult to solve using just some blocks available in Simulink. However, ETAP, Open DSS, MATPOWER can have ability to do such studies.
  • asked a question related to Power Systems Simulation
Question
3 answers
Hi
I am not electrical engineering student but currently I am looking to measure the pulse width( in fs) of received signal. Given pulse width 10^-13 s, with power level let 1Watt of transmitted pulse, when this pulse is transmitted on channel it is distorted by noise model N, and weakened by attenuation A.
what will be the pulse width of received signal. I can analytically solve it for received signal power/energy distribution (pdf of received signal energy) but I can not calculate the actual received pulse and its pulse width.
Relevant answer
Answer
The width of the signal remains unchanged. 10THz=1/10^-13
You have to know the frequency response of the channel. Impulse response or a step response. This problem identifying linear dynamic system.
I do not know how to measure these short pulses. It is almost an optical range. Look here DOI:10.1109/CLEOE-IQEC.2007.4387090  A. Bartels  All-Optical THz Oscilloscope
  • asked a question related to Power Systems Simulation
Question
39 answers
I currently use MS visio for drawing Power Electronics circuits and looking for a better one. Any one who can guide me, Please.
Relevant answer
Answer
For quality and simplicity, I would go for LATEX with its circuitikz library (http://www.texample.net/tikz/examples/tag/circuitikz/). TikzEdt that helps me drawing using tikz.
  • asked a question related to Power Systems Simulation
Question
1 answer
Hi guys,
I just would like to know if you could recommend me any good laser company for purchasing for this CW 690 nm laser diode with >1W output power I am interested in. 
I will develop 345 nm CW laser generation from 690 nm laser diode. if you have similar work experience about diode harmonics, could you give some advice or recommend some references.
the type of the 690 nm laser diode? I choose FP or VECSEL.?
I would be very grateful if by your experience you know of a good one you could recommend me. 
Many thanks,
Zhai Suya
Relevant answer
Answer
click on the link  it may helps you
  • asked a question related to Power Systems Simulation
Question
4 answers
hello. I want to use 123 node test system for switch placement. Can anyone help me about the types of conductors to use? its given data or other ones?  because it is imbalance and i want to implement in balance condition.
thanks.
Relevant answer
Answer
Hi Pouya,
Yes, but the system parameters provided are realistic and authentic !
If required, a user can always split the unbalanced parameters into positive, negative, and zero sequence impedance or admittance matrices; and thereafter use only the positive sequence parameters for balanced studies.
Anyway, that was only a suggestion. Perhaps balanced data may be available from other sources - one can try !
With best wishes.
-Sanjay
  • asked a question related to Power Systems Simulation
Question
6 answers
Dear All,
This is a real world problem:
There is a PV plant which covers 10km x 2km. In the center of the plant, there is a weather station, which measures GHI / POA irradiations and reference cell temperature.
I am going to simulate a PV cell model for each string in the plant. As we can see, only weather station data are available.
Thus, is it possible to estimate irradiation / cell temperatures in every location of 10km x 2km area based on the weather station measurements?
There are companies which can provide 15m x 15m resolution irradiation / cell temperature, how can they achieve it ?
Thanks.
Relevant answer
Answer
As measured on the metrological scale, what you are exactly looking to estimate is the microclimate of the station which would depend on several constraints rather than only temperature and humidity.  The NOCT of cell in strings should be similar but again, it depends on surrounding vegetation/ water bodies. The model could be implemented on an approximate GHI. 
  • asked a question related to Power Systems Simulation
Question
3 answers
Hello Researchers, 
I need high resolution say, a measurement interval of 15 mins - 30 mins solar radiation data for my research. Most of the hourly data archives have average hourly solar radiation which don't accommodate the variation in horizontal direct beam radiation (looks like a smooth deterministic curve). I need to see the deviations in radiation due to cloud and other obstructions if any.    
Please comments your suggestions. Thanks in advance!
Relevant answer
Answer
I think this paper authors works with the same field measurement that you are looking for:
Regard.
  • asked a question related to Power Systems Simulation
Question
6 answers
I need to valid test system of Radial low-voltage unbalanced distribution system. Each one of the Lines & loads in this system is an impedance (as R & X ).In this test system, the real & reactive power can be defined or not.The important cases at the required test system are:
1-Radial Distribution system
2-Low-voltage(220-240 V)
3-unbalanced in load side
4-Impedance values of lines & loads
Relevant answer
Answer
hI
I presume that this is typical RDN(Radia Distribution Network) at  the secondary distribution feeders supply residential and commercial customers at 120/240/440 volts.
In general, the distribution system is the electrical system between the substation fed by the transmission system and the consumers’ premises. As for  f the current case the voltage level  is set for 220-240 V, it is require to maintain requirements for such type distribution in order to guarantee consumers power rate requirement mainly the proper voltage, loading  and reliability issues.
RDN unbalanced are prone for Dynamic change in imposed load, High R/X ratio, and contain also extremely large number of nodes and branches.
You might find Ladder network methods implementation in some section of  the system in order to finds suitability and practical application for single source radial structure networks with high R/X ratio;
You may also use  SVC or Series compensation at substation fed in order to regulate voltage and  Reactive power correction.
i suggest to follow   the below link as well...
  • asked a question related to Power Systems Simulation
Question
8 answers
Hi my friends I need to regulate and control efficiently the battery charge with the output voltage and current than flow from the buck converter, can anyone give me some ideas in order to improve it?.
Relevant answer
  • asked a question related to Power Systems Simulation
Question
14 answers
Earthing is return path. If my source is isolated from earth we don't need earthing. Then why we use earthing based system?
Relevant answer
Answer
Grounding is a North American term for Earthing in the European Continent. They have the same technical meaning globally.
IEC standard 60364 defines TN and IT systems as solidly earthed and unearthed electrical distribution systems (normally for low voltage - i.e., below 1,000V a.c. or 1,500V d.c.)
Apart from Norway, almost 99% of other countries use TN system for public distribution systems. This is because an earthed system has the following main advantages over an unearthed system;
  1.  to provide safety to personnel during normal and fault conditions by limiting step and touch potentials to a certain known and manageable value;
  2. to assure correct operation of electrical and sensitive equipment by providing an absolute 'earth' reference voltage value;
  3. to dissipate the energy from direct or indirect lightning strikes;
  4. other advantages are given in 'Advanced Electrical Services Engineering' which can be obtained from CIBSE bookshop - Link.
An IT system is normally used only where there is a requirement that under a first earth fault condition, the supply should not be interrupted and shall still be able to provide a continuous service to say one or several pieces of essential (e.g., life-safety or fire-protection) circuits.  Instead of immediate disconnection of the circuit or equipment under a single earth fault condition, since there is no earth return the faulty circuit will remain in working condition, there will be earth fault monitoring device to raise the alarm that an earth fault has been detected. This allows e.g., the hospital staff to bring in a new piece of standby equipment, set it up and have it working before replacing the faulty piece of equipment.
  • asked a question related to Power Systems Simulation
Question
3 answers
How can we correct the power factor of two switch non-inverting buck-boost converter? because in boost mode it is easily corrected but in buck mode input current is discontinuous ?
Relevant answer
Answer
If you want a very continous DC supply current, I would use an LC filter in the DC supply.
  • asked a question related to Power Systems Simulation
Question
4 answers
Would like to know how to model a constant power load in SImulink/Simpowersystems. I'd like to be able to simply change the power requirement of the load which is being powered by two boost converters. Any help would be great, thanks.
Relevant answer
Answer
Cheers guys.
  • asked a question related to Power Systems Simulation
Question
2 answers
Any system example on which LINKNET  is applied will also work.
Relevant answer
Answer
Hello Brijal Mehta,
LinkNet is one type of linked listed used to store and perform calculations involving sparse matrices. I have a few notes I lectured from on Linknet, which I may be able to find if required. We used LinkNet extensively here (due to R. Podmore coming from the University of Canterbury) but have more recently use bifactorisation by Zollenkopf  [1].
[1] K. Zollenkopf. Bifactorization: Basic computational algorithm
and programming techniques. In Oxford, edi