Tausif Ahmad added an answer:Do you have any good book/research article related to smart grid planning?
Demand Side Response and integration of renewable.
Send your personal mail id , i will help you on smart grid.Following
Pisupati Sadasiva Subramanyam added an answer:I have monthly load how can I extract daily or hourly load from it?
Hi all, I have monthly load how can I extract daily or hourly load from it?
You may also take a set of daily or hourly data and see whether this curve you have chosen fits fairly well with this data. If so you may use that curve for interpolation from your monthly data.
you can try curves with polynomials of a different degree.
This is a cumbersome Procedure and still we are not 100% confident of the Results we gt. It is a Rough Approximation.
Mostafa Eidiani added an answer:Which is the best power systems analysis software for small systems, ergum industrial systems?
You can see also this link
Mostafa Eidiani added an answer:How the insufficient damping of low frequency oscillations limits power transfer capability in power system?
Can someone please give me an example?
You can see also this link
Meera Karamta added an answer:For a dynamic simualtion of a multi-m/c system with TCSC, what could be the ideal value of initial firing angle?
I want to perform EMTP based dynamic simulation of a multi-machine system having TCSC. One of the reference paper suggests using initial firing angle 8 degrees more than the TCSC's resonant point. The authors have justify this as based on engineering judgement..
Is there any specific limit?
Thank you Parekh Sir.. Will take into consideration.Following
Sivanantham S added an answer:How can we estimate power (RTL level) in RTL Compiler before performing actual synthesis?
Building RTL Power Models in RTL Compiler
It is always good to build power model before performing synthesisFollowing
Muharem Mehmedovic added an answer:In a synchronous machine modelling how do you derive the flux linkage equation in dq coordinate for a synchronous machine modelling?
For mutually coupled windings along d-axis and q-axis
The question could be more precise because there is no mutual couplings between d and q axis. The equations for flux linkages in d and q axis starts from their form in the stand still frame. After transformation from this to the rotor frame (this must be done for all quantities: inductances, resistances, voltages, currents and flux linkages) the final equations for flux linkages shall be derived. Also, the systematic approach can be found in: P. C. Krause, Analysis of Electric Machinery!Following
Yasser E. Abu Eldahaba added an answer:How to make an interface between matlab and pscad?
Hello, everyone I'm working on optimization of coordinating overcurrent relay I wrote allocation codes and optimization code in matlab but I need to recall mfiles in PSCAD. I want o know is that possible to link between matlab and pscad wich I able to use matlab codes in Pscad?
Copied old posts: The attachment includes the steps to make that interface.Following
Sándor F. Tóth added an answer:How to measure the difficulty of a Mixed-Linear Integer Programming (MILP) problem?The intuitive answer is the number of binary variables, when solving the MILP through the branch-and-cut algorithm. But, is the number of binary variables really the main characteristic that increases the computational burden of an MILP?
In the case of the Unit Commitment problem (UC), it has been proven that including the startup and shutdown binary variables decreases its computational burden in comparison with a UC using only commitment binary variables (without the startup and shutdown ones).
So if the quantity of binary variables does not directly influence the computational burden of a UC, how to measure the computational burden of an MILP problem?
I think it is common in MIP optimization to have a few global constraints (e.g., enterprise-wide smooth workflows) whose number doesn't change with the size of operation (the number of decision variables) but at the same time it gets easier to satisfy them when more items are available. The number of "local" constraints can still explode in response to the higher number of variables but this will likely not have any impact on difficulty if the local regions are independent.Following
Sheng Chen added an answer:Inverter for Solar Power Systemhi , I am searching on "Inverters used in PV systems". I will be really grateful if someone can help me to get more details on the advancements in the fields.Also what are the project possiblities in this area which can be completed in maximum of 4 months. ?
Hi sir. For solar inverter research, I suggest you could login homepage of some solar inverter manufacturers, then download the datasheet and installation diagram.
Hope it can help for your work.Following
Maksim Prudov added an answer:What is the cause of oscillatory instability of power system?
I examine a simple two-machine model of the electrical system, which takes into account field circuit dynamics and excitation system (Kundur P. Power system stability and control, McGraw-Hill, New York, 1961).
When power generation reaches 1.3 p.u. appears a pair of complex eigenvalues with positive real part. This mode has a frequency of 1.4 Hz. Analysis of the participation matrix showed that this mode is related to the flux linkage of field winding and excitation system. I checked the voltage stability using the network dV/dQ curve (using the Jacobian). But the network dV/dQ curve change sign much later.
What is the cause of oscillatory instability of power system model?
You can see the angle-power curves for my model in attach. Green corresponds to the stability, blue - oscillatory instability, red - monotonic instability.
In my case, oscillatory instability is directly related to the action of ARV, coefficient K5 (see Kundur Power Systems Stability and Control p.759) changes its sign. Should be noted that the model was not included PSS.Following
Bala Murugan s added an answer:What software will help me accurately measure dynamic power dissipation of a circuit that is coded in verilog hdl?
I have worked in Cadence NCLaunch tool to measure power dissipation. However, presently I am unable to access Cadence and as there is no freeware available on the net, I am out of options. Please suggest me some other tool for my research purpose
You have to have either Cadence RTL compiler or Synopsys DC, without this if you are run the code to measure the dynamic power, you will receive many questions from the reviewer and at the end you are frustrated about your work. So, better use any one of the tool mentioned above and generate either VCD file or TCF file and calculate the dynamic power. Make sure that your VCD or TCF file covered 100% switching activity while tool read it.Following
Jethro Betcke added an answer:How can find data of a real microgrid for designing an MPC-based controller?
I want to design a EMS systems for a MicroGrid that determines real and reactive power set points for components of a real world MG, e.g. DGs, Compensators, Loads etc.
I need all of the information/data about this MicroGrid for design a MPC-based controller.
I prefer that this system includes a PV, a wind turbine, a diesel generator, and a battery storage device.
Let me help you on the way:
Javad Modarresi added an answer:How do you model the synchronous condenser in DIgSILENT?
I want to model the synchronous condenser in DIgSILENT. How can it be done?
Synchronous condenser consume little active power. Moreover, DigSILENT gives error in very low power factors (Simulation not converge). My network is IEEE 14 bus test system.
In DigSILENT, the setting of power flow tap is only applied to the power flow analysis and synchronous machine exchanges the active power with network in the time domain simulation even in the P=0 condition.Following
Albert Juhasz added an answer:What is the physical interpretation of the energy conversion factor for power generation from steam turbines?
I am using a model for power generation from steam turbines to be the difference between the superheated steam enthalpy and the outlet saturated low pressure steam enthalpy multiplied by the efficiency of the turbine. The power calculated is smaller than the actual power that is generated by real power plant data. However, I figured out that if I multiplied the enthalpy difference with a certain factor it will reproduce the actual plant data, and the model worked for data for many different power plants. I cannot find a physical interpretation for this factor. I only found one paper that explicitly shows this factor and called it " energy conversion factor" with no physical interpretation.
Natalia and Maddali essentiall y answeredyour question.Following
Abdulla Rahil added an answer:To input measured variable wind speeds for mathematical modelling in simulink?How to input variable wind velocity to the simulink model correspondingly to get the output for variable speed, using the lookup table in simulink is giving an error. I want to give wind speed measured for every 10mins and to dump/interface those in simulink model.
sorry this is exactly is my question if you got any answer plz let me nowFollowing
Salah Eldeen Gasim added an answer:Who can help in application of neural networks (NN) in load flow analysis?
Supply me by any documents, examples, and MATLAB codes.
Your efforts are highly appreciated Mr. Chathura Senanayake,
I will do that, and get back to you later on.
Thank you so much.Following
Morteza Shabanzadeh added an answer:Microgrid test system in Digsilent or matlab simpower?I want work on my project in the field of "Microgrid." I need a test system of microgrid in digsilent or matlab simulink. If anyone here has this file, please give me.
Just read and collect the case studies of academic papers concerning Smart Grid and Microgrid issues.
Okan Ozgonenel added an answer:Has anyone used matpower for simulation?Am having some doubts related to switching off of generators.
I also recommend you to use PSCAD software, which is more powerful than matpower. Please contact to me if you have any questions. Prof. Dr. Okan OzgonenelFollowing
Michael Hainzl added an answer:In a pipe electrode used for earthing, will the current flow both inside and outside of the cylindrical surface area?I was just going through BS 7430, where a formula was given in Page No. 29 for calculation of current density of one electrode. Now in order to calculate the number of electrodes required to take the short circuit current of the system, I need to divide "J" with the surface area. However, when calculating the surface area of the cylinder do we have to calculate only "2 x 3.14 x r x h" or "2 x 3.14 x h x (r +R)" where "r" is the inside diameter and "R" outside diameter of the pipe electrode.
The inner surface of a hollow grounding electrode (a pipe) isn't going to help dissipate current into the surrounding ground, no matter how you connect it. If you assume the grounding electrode can be filled with earth, it could, in theory, conduct a tiny amount of energy out the ends of the pipe. But in a practical application, the fraction of current out the ends of the pipe from the inner surface would be so small, it's not even worth your time to try and calculate the result.
All that being said, I went back to the original post and it appears this is a textbook question, so making practical approximations for real applications might cost you in this case. Perhaps the objective of the problem is to demonstrate how little current would flow from the inner surface of the pipe?Following
Mahesh S Illindala added an answer:Inverter based microgridWhen stability analysis has to be performed in an inverter based microgrid, is there a need to convert the load flow variables from network frame to the machine (inverter) frame?
All the system dynamic equations have to be on the same reference frame.Following
Salah Eldeen Gasim added an answer:Which loss has to be considered for transformer losses?The technical specification of our project has specified both fixed and capitalization factor-based losses. Now our vendor is asking for which losses need to be considered.Transformer iron-loss (the power lost in a transformer's core) is also a considerable part of transformer no load losses. The iron which is meant here represents the transformer core. Transformer iron loss is divided to two: Hysteresis loss and eddy current loss. Both depend on type of the core material, the current frequency, the maximum value of the magnetic field and thickness of core sheets. The main cause of hysteresis loss is the magnetic field reversal. Eddy currents are the currents that flow in the core. They are due to the emf which is generated in the core (as the flux cuts it) by the same principle of the induced voltage in the secondary winding of the transformer.Following
Srikanth Pullabhatla asked a question:Does anyone have experience with the design of a Series reactor?We have got a 33kV Busbar of Short Circuit rating of 31.5kA and this busbar will be connected through a Tie-feeder from another busbar of different short circuit rating. Our client has asked for a Series Reactor in the Tie-feeder. Now I want to know how to design the rating of the Series Reactor.Following
Mehdi Hedayatpour asked a question:Can anyone describe a method for open-transition transfer for synchronization of microgrids?Thanks in advance.Following
Kalola Dhara asked a question:Can anyone help me with the theory or a simulation of UPQ in weak grid using DFIG?I saw it in one research paper but i didn't get this theory. Interesting to know about UPQC.Following
Thodoris Kourmpelis added an answer:How to operate circuit breaker during fault condition on MATLAB?When we are simulating the fault on power systems, using MATLAB, how to operate the circuit breakers by providing external signal after the fault is developed?@Vivekanandan : I think a lookup table would be suitable for your application. Also if you implement something like this at Simulink try to also add a gaussian filter in order to prevent measurement irregularities! If you have any news regarding your work please send me an email. My mail is : theo.kourmpelis [at] gmail [dot] com . I have made some similar fault detection studies but for DC grids. Good luckFollowing
Yang Hong added an answer:does any one please help me with PI controller tuninghi all, i need to tune my PI controller in MATLAB simulink for minimizing error for a decoupled d-q control loop. if any one is interested to look forward to the problem, i will emphasise.
thank you(1) A typical PID tuning procedure: (1) Use relay control to estimate the control model (or control plant); (2) Use Z-N formula to initialize Kp and Ki; (3) use trial and error to adjust Kp and Ki or other method such as iterative feedback tuning (IFT), internal model control (IMC), etc.
H. Hjalmarsson was elected to the Class of 2013 IEEE fellow last year due to his fundamental contribution to iterative feedback tuning. The key contribution of IFT is tuning controller parameters for those control model (or control plant) whose parameters are difficult to be identified relatively accurately, in other words, iterative feedback tuning was proposed to solve controller tuning issues caused by plant uncertainty.
H. Hjalmarsson, M. Gevers, S. Gunnarsson, and O. Lequin, "Iterative feedback tuning: theory and applications," IEEE Control Systems Magazine, vol.18, no.4, Aug 1998, pp .26-41,
By cooperating with his peer researchers including Stanford University researcher, H. Hjalmarsson integrated iterative feedback tuning with PID controller to solve controller tuning issues caused by plant uncertainty.
WK Ho, Y Hong, A Hansson, H Hjalmarsson, and JW Deng, "Relay auto-tuning of PID controllers using iterative feedback tuning," Automatica 39 (1), January 2003, pp. 149-157. Available from the following RG Link.
W.K. Ho, T.H. Lee, H.P. Han, and Y. Hong, "Self-Tuning IMC-PID Control with Interval Gain and Phase Margin Assignment," IEEE Transactions on Control Systems Technology, 9(3), May 2001, pp. 535-541. Available from the following RG Link.
(2) Only PID Control and Smith Predictor were listed in the “Leaders of the Pack” InTech’s 50 most influential industry innovators since 1774. Available from the following link.
PID Control was listed twice (the dominant control method in the industrial application) -- (1) John G. Ziegler and Nathaniel B. Nichols and classical PID Control; (2) Karl Johan Åström and modern PID Control (IEEE Medal of Honor, 1993)
The next popular method is Smith Predictor: Otto J.M. Smith and Smith Predictor.
C.C. Hang, K.J. Astrom, and W.K. Ho, "Refinements of the Ziegler-Nichols tuning formula," IEE Proceedings on Control Theory and Applications, 138(2), March 1991, pp.111-118.
This paper has been implemented by Maplesoft Inc. for MapleSim Control Design Toolbox
K.J. Åström, T. Hägglund, C.C. Hang, and W.K. Ho, "Automatic tuning and adaptation for PID controllers - a survey," Control Engineering Practice, 1(4), August 1993, pp.699-714.
K.J. Åström, C.C. Hang, P. Persson, and W.K. Ho, "Towards intelligent PID control," Automatica, 28(1), January 1992, pp.1-9.
Control theorectic approaches have been applied to model the interactions between an overloaded SIP server and its upstream servers as a feedback control system in two different scenarios - round trip delay control (IEEE ICC 2011) and redundant retransmission ratio control (IEEE Globecom 2010).
Round-Trip Delay Control (RTDC, implicit SIP overload control) algorithm: Y. Hong, C. Huang, and J. Yan, "Design Of A PI Rate Controller For Mitigating SIP Overload," Proceedings of IEEE ICC, Kyoto, Japan, June 2011.
RTDC implicit SIP overload control algorithm has been recommended as White Paper by TechRepublic (CBS Interactive)
IEEE ICC 2011 presentation slides for RTDC implicit SIP overload control can be downloaded from the following RG link.
Redundant Retransmission Ratio Control (RRRC, implicit SIP overload control) algorithm: Y. Hong, C. Huang, and J. Yan, "Mitigating SIP Overload Using a Control-Theoretic Approach," Proceedings of IEEE Globecom, Miami, FL, U.S.A, December 2010.
RRRC implicit SIP overload control algorithm has been quickly adopted by The Central Weather Bureau of Taiwan for their early earthquake warning system.
T.Y. Chi, C.H. Chen, H.C. Chao, and S.Y. Kuo, "An Efficient Earthquake Early Warning Message Delivery Algorithm Using an in Time Control-Theoretic Approach", 2011.
Short review and comments on this implicit SIP overload control algorithm by former IEEE TAC Associate Editor S. Mascolo:
L. De Cicco, G. Cofano, and S. Mascolo,"Local SIP Overload Control", Proceedings of WWIC, June 2013.
IEEE GLOBECOM 2010 presentation slides for RRRC implicit SIP overload control can be downloaded from the following RG link.
Journal paper (SIP Overload Control) not only conducts more theoretical analysis of Round trip delay control (RTDC) and Redundant retransmission ratio control (RRRC), but also discusses how to apply RTDC algorithm to mitigate SIP overload for both SIP over UDP and SIP over TCP (with TLS).
Y. Hong, C. Huang, and J. Yan, "Applying control theoretic approach to mitigate SIP overload", Telecommunication Systems, 54(4), 2013, pp. 387-404.
Survey on SIP overload control algorithms: Y. Hong, C. Huang, and J. Yan, "A Comparative Study of SIP Overload Control Algorithms", IGI Global, 2012, pp. 1-20.
Open-source SIP/VoIP project discussion archive
IETF-RFC "SIP Overload Control" discussion archive
API-RCP(TCP Congestion Control):Y. Hong and O.W.W. Yang, "Design of Adaptive PI Rate Controller for Best-Effort Traffic in the Internet Based on Phase Margin," IEEE Transactions on Parallel and Distributed Systems, 18(4), April 2007, pp. 550-561.
Review, comments, and extensive evaluation on API-RCP:
H. Zhou, C. Hu, and L. He, "Improving the Efficiency and Fairness of eXplicit Control Protocol in Multi-Bottleneck Networks", Elsevier Computer Communications, 36(10-11), June 2013, pp. 1193-1208.
(3) Control Theory developed in the twentieth century: 25 Seminal Papers (1932-1981) Selected by IEEE Control Society in 2000.
IEEE Control Systems Award
IFAC Giorgio Quazza Medal
4 co-authors of 25 Seminal Papers (1932-1981) awarded IEEE Medal of Honor (the highest IEEE award): Nyquist(1960), Kalman(1974), Bellman(1979), Astrom(1993).
R.E. Bellman and K.J. Astrom, "On structural identifiability," Mathematical Biosciences, 7(3-4), 1970, pp. 329–339.
Richard E. Bellman Control Heritage Award for US control systems engineers and scientists (US citizenship)
Ragazzini's notable students are Rudolf Kalman (see Kalman filters), Eliahu Ibraham Jury (see Z-transform) and Lotfi Asker Zadeh (see Fuzzy sets and Fuzzy logic).
K. Astrom, E.I. Jury, and R. Agniel, "A numerical method for the evaluation of complex integrals," IEEE Transactions on Automatic Control, vol.15, no.4, Aug 1970, pp.468-471.
"To control theorists, Nyquist is no doubt best known as the inventor of the Nyquist diagram, defining the conditions for stability of negative feedback systems. This has become a foundation stone for control theory the world over, applicable in a much wider range of situations than that for which it was orignally enunciated." Hendrik W. Bode, Harvard University, USA, 1977.
Biography of Harry Nyquist, University of Cambridge, UK, 2003.
"Between 1920 and 1940 he published a series of papers on research in telecommunications which are arguably the most outstanding set of scientific contributions since Newton (apart from Einstein!)."
K.J. Åström, "Harry Nyquist (1889-1976): A Tribute to the Memory of an Outstanding Scientist," Royal Swedish Academy of Engineering Sciences, 2003.
American Society of Mechanical Engineers (ASME) Nyquist Lecturer Award
(4) For academic control community,
ACC 2012 Plenary and Semi-Plenary Lectures
Plenary: Accomplishments and Prospects of Control
Abstract: There are many success stories and major achievements in control, something remarkable for a field as young as 50 years. In this talk we will sample these accomplishments and speculate about the future prospects of control. While there are examples of feedback from ancient times, extensive use of feedback paralleled industrialization: steam, electricity, communication, transportation etc. Control was established as a field in the period 1940-1960, when the similarities of control in widely different fields were recognized. Control constituted a paradigm shift in engineering that cut across the traditional engineering disciplines: mechanical, electrical, chemical, aerospace. A holistic view of control systems with a unified theory emerged in the 1950s, triggered by military efforts during the Second World War. The International Federation of Automatic Control (IFAC) was formed in 1956. Education in control spread rapidly to practically all engineering disciplines. Conferences and journals also appeared. A second phase, driven by the space race and the emergence of computers, started around 1960. Theory developed dramatically as did industrial applications. A large number of sub-specialties appeared and perhaps due to this, the holistic view of the field was lost. In my opinion we are now entering a third phase driven by the ubiquitous use of control and a strong interest in feedback and control among fellow scientists in physics and biology. There are also new areas driven by networked systems, autonomy and safe design of large complex systems. What will happen next depends largely on how we respond to the new challenges and on how we manage to recapture the holistic view of systems. Key issues will be education and interaction with other disciplines.
Semi-Plenary Lectures also discuss promising research topics.
8 wonderful presentations in control symposium "Paths Ahead in the Science of Information and Decision Systems", Massachusetts Institute of Technology (MIT), USA, November 12 – 14, 2009.
Panel on Future Directions in Control, Dynamics, and Systems, Richard M. Murray (chair), California Institute of Technology, April 2002
R. Murray, K. Astrom, S. Boyd, R. Brockett, and G. Stein, "Future Directions in Control in an Information-Rich World," IEEE Control Systems Magazine, 23(2), April 2003, pp.20-33.
Currently US National Science Foundation (NSF) funding support emphasizes the real-life applications and/or industry needs instead of pure theoretical work in control.
"The Control Systems (CS) program supports fundamental research on control theory and control technology driven by real life applications. .... that are motivated and derived from real-life applications and/or industry needs."
To celebrate the golden anniversary, IFAC Automatica will publish in the 50th volume throughout the year, special survey/overview papers, on selected topics, some tracing the history on some mature topics and areas, others focusing on newly emerging areas, with forecasts into the future. The survey paper published by the 1st issue provides an overview of the developments in the control field from its early days.
K.J. Astrom and P.R. Kumar, "Control: A Perspective," Automatica, 50(1), January 2014, pp. 3-43.
About Power Systems Modelling
Simulation of Power Systems as a whole and of each separate component