Science topic

# Microgrids - Science topic

Explore the latest questions and answers in Microgrids, and find Microgrids experts.

Questions related to Microgrids

I would like to design a microgrid based on an IEEE bus system for the purpose of validation of a certain technique. Should the MG have the same standard loads of the IEEE bus system ?

Can I design the MG (say based on 14 bus system) and have only few Kilowatts as a load (50 KW load) , does this make sense or it deems impractical?

Hello,

I am doing a Matlab/simulink simulation based on microgrid control using model predictive control. In my simulation, I have a 3-phase grid with PV and battery storage. The main goal is to control the system using MPC at a very precision level. Initially, I am feeding frequency at PCC as a variable to the MPC. Whenever I run the simulation, the error has occurred since the 3-phase grid has constant parameters. In that case, how can I resolve this? Or, if anyone has any simulink file for MPC in MG can share. I will really appreciate your help.

Thanks

Any researcher who is interested in working together in the field of Powers Electronics & Drives, Converter & Inverter Design, MPPT Techniques, Solar Photovoltaic Systems, Microgrid, EV Charging Stations. And also interested in publishing good quality paper. Kindly contact me. And also here Give your suggestion and feedback.

The degrees of freedom of a system is the number of variables needed to completely describe the system (correct me if I am wrong). From a steady-state point of view, the response of an AC microgrid can be determined by the output voltages of its DGs (ie,

**v**and_{od}**v**) as by specifying all voltages, all currents will also be specified. Even though v_{oq}_{oq}is usually set to 0. (v^{*}_{oq}=0)**My question:**

In the context of secondary control of microgrids, scholars tend to control

**frequency**,**voltage**, and the**share of power**for each DG.**How is it possible to achieve these 3 control objectives with only 2 variables?**Hello evryone.

Please I want to know how regulate de frequency deviation in microgrid, and also how to do to make a firt order transfert function which are used to estimate the sources like PV, WTG, DEG, BESS and so on.

Thanks

If we have a microgrid that combined from solar panels and battery , battery is selected to be grid forming source, my question is: battery inverter is individual or built-in solar inverter, which means solar inverter connected with solar array and batteries

Sometime we say it is important to control microgrids to have a good frequency and voltage stability problems. however, please I want to know how.

Thanks

I developed a small-signal model of a grid forming microgrid using this reference

With the same parameters, however, I didn't get the same eigenvalues, (small displacement)I checked the state-space matrices lot of times but couldn't figure out the mistake.
The obtained results are attached.

Could anyone help or suggest a solution?

because we have a frequency stability problems in the microgrids, please I want to know how to measure frequency?

thanks

Journals with a high/moderate impact factor are needed to incorporate EVs considering a publication and review time not to exceed 5-6 months.

Hi all,

I am modeling a hydrogen-renewable microgrid and want to use average models of converters and inverters to reduce simulation time (my current microgrid model with IGBT and PWM converter and inverter took 2 hours to simulate 24seconds in Simulink, which is too long). Currently, I have successfully modeled the DC DC boost converter and buck converter, however, for the bidirectional DC DC converter, I have not been able to simulate that. So I wondering if someone had done it in the past and be able to send me the simulation file or any document related to this. Thank you guys so much.

Best regards,

Phan Văn Long

P/S: Below is the simulation file with an average model of DC DC boost converter, buck converter and a average model of bidirectional dc dc converter (connect with a pv panel - mppt boost converter)

Which renewable energy source is the best for optimal operation of microgrid system?

Dear researchers, what are the proposed methods to optimize battery SOC and diesel fuel usage , as an energy management strategy for off-grid microgrids ?

Such system are exposed to uncertainty and high penetrations of renewable resources.

I am working on a Microgrid planning and I discovered that the current existing generators of one of the communities are able to meet their demand within the given planning horizon of 20 years.(the is the result obtained from GAMS). When I implemted same model in Homer Pro,Homer replaced some gens even without using up the life of some other already existing gens. However, when I assume a very high replacement cost(higher than used in GAMS),homer uses the existing gens and didnt replace.I found this weird or there is something that I do not understand about how the two softwares works. I know most people here have worked with both softwares and could give an insight on the behaviours of these two softwares. Please I am really on a hot seat to answer this question and any help from any one here would be highly appreciated?

I am implementing Distributionally robust optimization using bender decomposition in GAMS. Can anyone provide me with any helping material or source code for the implementation of expansion planning problems?

A question about Matlab implementation of estimation technique

how to add BEES to a networked microgrid system using MATPOWER ?

I have seen many papers where the authors explain the benefits of their proposed circuits. Honestly, saying these benefits are not impactful if you can't describe a specific application where it can be used, which should be the ultimate purpose? Using words like microgrids, nano-grids, high-frequency applications, high-gain converters, etc. with no concrete discussion in the rest of the paper seems to be spreading rather fast. My suggestion is to allow a paragraph or two suggesting how the proposed converter can be used in some applications and how it is beneficial with a top-level comparison to the existing state-of-the-art.

Let me know what you all think.

I note that virtual damping resistors and virtual impedances are usually considered to solve the problems that may arise due to the dependence of the conventional droop controller performances on the external line impedance e.g. Rocabert et al (2012)

I would like to know in which microgrid scenarios a damping resistor (i.e a virtual impedance with resistive component only) could be more suitable than a virtual impedance.

If possible, kindly also recommend to me some paper where the sizing of said resistors/impedances is described in detail.

Thanks in advance!

I am trying to review the structures of Islanded microgrid, its economic analysis, and improving its efficiency and stability. so I need to know the best structure that is existing now.

any suggestions for estimation techniques ?

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.

Thanks guys!

The model has a microgrid is connected to the main grid. Calculation of the rate of change of voltage is required for the islanding detection technique I need to use. Is there any MATLAB code or Simulink or suggestion about that?

Hello everyone, When feeding off-grid users the PV-HESS-DIESEL resource suite, what diesel fuel conditions should be monitored and implemented in an energy management strategy?

Here, what are the thresholds or limitations to consider when operating a diesel generator 🔌 subject to PV and battery SOC 🔋 outputs as well?

Can anyone share a related paper or provide a detailed analysis?

Thanks a lot.

IEC 61850 is a standard for substation automation, and IEC 60870 is a standard for telecontrol implemented in SCADA systems. I want to know what the most appropriate to use in a small microgrid is, and what the differences are between both of them.

Thank you.

As an electrical researcher, which journal would you choose as your preferred journal for publishing your research, if possible?

This selection includes a maximum of three journals (in order of preference) and the selection criteria can be based on any of the trends (power system, power electronic, smart grid, etc.).

Assume we have a microgrid consisting of two inverters

Sir/madam,

I am currently doing research in the area of microgrid design. I am exploring literature to check any standards/standard test system (like IEEE 33 bus system etc.) for design, sizing, configuring and testing the performance of microgrid system. IEEE 2030.8 addresses about standards with respect to controllers , IEEE 1547.4 addresses about standards relating operations and integration of DER.

Most of the papers consider case studies for sizing microgrids.

So is there any other source which I can refer? Kindly seek your advice..

Reference:

Hi,

(I have asked this questions previously, but I believe it was too general. I have tried to be more specific here)

I am trying to establish an islanded microgrid with 2 inverters running in parallel to supply a single load. I want to use droop control so I can then adjust the power sharing between them.

I am struggling to get 2 inverters to synchronise. I can get them to supply the same voltage, but the currents work against each other in the load.

What I have tried:

1. Grid forming and Grid feeding. When I add the Grid feeding inverter, I can not control the voltage that it injects the current at. If I give it it a Reactive power reference, it will inject current into the grid at that power level, it doesn't regulate the voltage. Therefore, it pushes the voltage of the load up I get instability in the system.

2. Grid supporting Voltage x 2. I have tried to put 2 Grid supporting Voltage sources in parallel. The problem here, is that if each inverter supplies a different power, this then adjusts the frequency that is injects its power into the grid and the miss match between the two frequencies of the inverters causes instability.

3. Grid supporting Voltage and Grid supporting Current. This has the same issue as point number 1. As there is no way to pin the voltage to anything, it is simply a current source that cant control the voltage it injects at. This causes instability in the microgrid I created.

Am I doing something wrong ?

The following paper has exactly what I am trying to achieve, but I get different results:

Does anyone have a Simulink model of 2 parallel inverters supplying a load in islanded mode?

Attached is the model of the Grid Supporting Voltage inverters in parallel that I have been working on. You can see that the currents of each inverter are working against each other.

Thank you

hello,

--- Is it possible to always get the maximum power that can be fed from a pv panel if i am imposing a stable voltage at a certain value on DC bus (by a certain controller) ?

Microgrid scheduling (two-stage programming) attempted to solve iteratively. But after some iteration results oscillating at two values (optimal price and power), that is, iteration 7 and 9 give the same result while 8 and 10 give the same result. Is it worth stopping at that point?

Can someone share typical microgrid model built in Digsilent Power Factory? Thanks a lot!

I am working on a DC-DC converter for a DC microgrid. In MATLAB simulation for reducing the ripple content, 48 Volt DC bus gets stable with a very large capacitor ranging from 35 F to 40 Farad. is it suitable to use such a high capacitance value capacitor? your suggestions and feed back will be highly appreciated . Thanks

Voltage state inverter microgrids are used to produce active and reactive power with renewable energy sources. This system is efficient or enough to replace the conventional generation system.

If a photovoltaic power generation system is to be added to the microgrid. The DG will inject active power of 150KW and reactive power of 30KVA into the grid in normal operating conditions. The inverter output voltage is 10KVac and the input voltage is 500Vdc. Use a three-phase inverter. suggest

a)grid-connected inverter for the project

b)control scheme for inverter(VSI)

c)control scheme for islanded necessary conditions

Hello Researchers, I would like to do both simulation and implementation level research work on the smart grid. How should I start from the beginner's level?

I have completed Bsc in EEE.

Any suggestion would be helpful.

Thanks in advance.

Please suggest

Papers related to Secondary control of microgrid

Model Predictive Control

Simulink Model for secondary control Microgrid

Need to learn pscad to models on microgrids but it's hard to find where to start. Are there any books or videos lectures?

Dear researchers, i am wondering if we can collaborate in a research project or paper concerning the predictive control and energy management of a cluster of DC Microgrids system.

I have already published papers in the energy management of such system.

Happy to contribute and exchange knowledge in this context.

hello everyone,

please i want to know how can i select the capacitance value of the DC link capacitor in my microgrid model, is there any range we can choose any value that maybe corresponds to our sizing, or it is depending on the value of the DC bus voltage ?

since it is working as a filter or damper for ripples, so the value of the capacitance should not be very high, otherwise the capacitance will play a role like a battery and no longer a filter ..

any help with this topic ?

thank you

The layers involved are the Generation layer, Transmission layer, Distribution layer, and the Customer layer of an IOT driven Microgrid.

I want to list the name of an advance attack type on each layer with description regarding how that attack is launched on that layer.

My findings, within the context of microgrid network, to prevent from each of the above-mentioned attacks in the future.

A detailed unified network diagram of each layer showing the locations of attacks within the ICT infrastructure of the microgrid network.

I am looking for hourly load and generation data for some real microgrids in operation. Please can someone help me in this regard? Any website or any other report? Thank You

I am doing a project on Development of Control and Protection techniques in AC Microgrid . So I need simulink model of PMU to measure positive sequence components of three phase voltage and current.

Hi all,

could you please help choosing the best RT simulator for electrical engineering research.

We are confused between the OPAL (op4510) or RTDS ?

it should have the ability to simulate a complete electrical power system (Microgrids) including generators, transmission lines, PV, wind turbines, relays, arrestors, batteries, super capacitors,....

besides, it will be used in real time control for different electric motors

the easier the programming the best.

thanks in advance

dear researchers, having a cluster of islanded DC-Microgrids supplied by PV- Battery- Supercapacitor, besides supported by backup diesel generator, how to control the diesel generator when compensating power unbalace of microgrids? Is it uaing dual loop cascaded structre, or using single current loop control.

Noting that the battery and supercapacitor are controlled with dual loop structrue considering the Dc bus voltage deviations.

Thank you for your reply and feedbacks.

Dear Researchers,

I'm looking for smart meter data and Microgrid data consists of energy consumption and generation by different resources. Please suggest suitable resources from where we can get latest datasets?

- Breaker interlock scheme

- Under-frequency relay (81) scheme

- Programmable logic controller-based load shedding

- Fast intelligent load shedding (ILS)

almost structure is same but how and which manner I say it is better than Microgrid

I am working on power quality issue in dc micro grid and its mitigation techniques please help me to develop a mathematical model/ dynamic model with ( PV+BOOST CONVERTER+ load+BATTERY+ SUPER-CAPACITOR AND FUEL CELL) mainly i am try to control dc bus voltage ripple mitigation

Microgrid scheduling (two-stage programming) attempted to solve iteratively. But after some iteration results oscillating at two values (optimal price and power), that is, iteration 7 and 9 give the same result while 8 and 10 give the same result. Is it worth stopping at that point?

Each microgrid has battery storage and RES. For this MIP problem game shows model status 1 (optimal solution) at both levels.

someone wrote FDZ as a false detection zone and others mentioned it as a fault detection zone. please provide any information, material regarding the calculation of FDZ for an islanding detection technique

Inverter generation is increasing significantly. The traditional protection schemes in distribution circuits are not well suited to locating faults where there is no overcurrent. What approaches have been tried and what are their success rates.

In a MicroGrid, a fault does not increase the inverter output but the output voltage is reduced and this is the only indication of a fault but the entire network sees essentially the same voltage. The fuses and other overcurrent devices likely are challenged to be able to isolate the faults so it seems that a trial and error approach of circuit isolation and restoration is the best method at this time.

Comments on approaches that have been tried with their effectiveness is most appreciated.

I am using GAMS in MINLP and it results in an infeasible solution any help ? reduced gradient less than tolerance

I don't know how to solve this issue

IS there any literature that analyze selection of window length of window in rooling/moving RMS of voltage signal?

I log data from oscilloscope, and then I calculate RMS voltage, but I am not sure the length of the window? Are there any rules about this?

Hello,

i work with a microgrid that contains a battery and a supercapacitor, i want to estimate the SOC of the battery ( modeled by a DC voltage source with an internal resistance ) according to the Coulomb counting method and therefore i need to select the initial SOC of my battery.\

i take the dimension of my battery from a paper where they say that the rated voltage is 48 V and they took the 28 V (as operational or nominal voltage), so since we use it in 28 V and its rated voltage is 48 V can we say that we use it not fully charged at the initial state ?

and how can i fix for ex my initial SOC at a specified value (50,70%..)

thank you in advance

hello,

i work on a controlled Microgrid and i want to test the robustness of my controller againt a white noise that may be added to the output or the input. Is there is any specific condition to follow in order to take a good choise of a noise power ? or it is somthing random ?

- Actually i tried to take it about 3% of the nominal measurement value, is this enough to be good choice ?

- in addition, i tried the two types of noises, but i noticed that the one applied on the output affects much more the system than the one applied on the output (in such a way, my system looses its stability with the output noise, but gives an acceptable performance with the input noise ) , is this reasonnable ? if yes, why ?

thank you in advance

Looking for PhD topics for renewable energy, Hybrid Power systems, Battery storage systems, microgrid etc.

What parameters should be metered?

What are the other considerations?

Remote monitoring?

Relevant sensors?

Relevant mathematical tools?

This is the first time that I had submitted a paper to a special issue of IET GTD "

**Future Distribution Grids and Integrated Energy Systems (IES)"**. The submission deadline was 31st March 2021. I wanted to know if any researcher here submitted their paper to this special issue or if anyone had experience with the timeline for their first review. ThanksKindly suggest some upcoming research areas/ challenges to explore in (but not limited to) sustainable planning, and performance assessment of hybrid renewable grids.

Much has been said and written about microgrid, but there is still no clarity on what the business model and the legal framework that make them viable should be. Within this new scenario, what will be the role of distribution companies ?.

Certainly, we are in a technological, political and economic environment that demands innovative solutions. I would like to start a collaborative discussion on this subject, with the aim of sharing the views of researchers from different places in the world.

I want to conduct a research on microgrid.

in an islanded microgrid to control voltage and frequency, we need control methods such as droop control.In general, selection of the power

sharing coefficients and controller parameters carefully will promote the system performance against disturbances and load changes. in the sys with multiple DGs using trial and error methods to select voltage and current PI controller parameters consume time. Is there a step by step way to do it?

I could not get desirable results using given parameters in special paper.

Plz give proper controller diagram if possible...i just want in islanded mode of microgrid...i want to track frequency deviations due to load changes... Becoz in VF control we always give const freq toh abc to dq block...

I am looking to implement DSM for energy management for microgrids with DERs. Most of the suggestion include Monte Carlo based simulation to find optimum point which consumes lot of time. Any other suggestion.

Dear all,

I would like to test Power Quality algorithms and indexes for DC grids, DC distribution networks, including DC electrified transportation systems, and show performance in real conditions (showing for example typical ripple, presence of supraharmonics, and most of all typical transients due to load step, variability of PhotoVoltaic and wind energy sources, etc.)

As for DC electrified transportation systems I have several recordings of pantograph voltage and current in 3 kV and 1.5 kV lines (railways and metros).

*Specific question*: are there accessible datasets or repositories of such voltage and current sampled waveforms for DC grids, microgrids, distribution networks? or do you yourselves have such recordings and could make them available?

We know that grid feeding inverter or grid following inverter is a current-controlled based inverter that follows the frequency of the main grid and feeds power according to the set value of active power reference and reactive power reference.

But in the case of contingencies, the frequency fluctuates at the load side, and we cannot change anything of the main grid. Is there any possibility to improve the frequency response through a grid-feeding inverter?

As is illustrated in many literature, optimization decomposition technologies such as Benders Decomposition or ADMM have been used in OPF , UC or ED models to keep the privacy of different agents and simplify the calculation of the whole model. However, the iterative relation of problem serialization is quite different from the parallel structure of real situation. The information exchanged between the main and sub problems may also reveal the user's privacy. My question is how to measure the privacy of exchanged information? Is there a suitable algorithm which can solve the problem perfectly?

Dear fellows,

I wish you a new year full of many new discoveries and health to all of you. The aim of this discussion is to ask you about the Low Voltage Distribution, Is it feasible a Distribution System in DC Low Voltage?

What is it your perspective on this topic for residential, commercial, communities, and industrial?

I am eager to read your opinion on this topic.

Best regards

I am trying to implement a fault detection method that is discussed by Ryoya et al in this paper "https://ieeexplore.ieee.org/document/8566578" and integrate it with a solid-state circuit breaker design I have developed to control a DC microgrid distribution system.

Then I started having a question that may sound a little bit naive. The paper I mentioned earlier uses current differential deviation i.e. change of current over time (di/dt) to identify faults. The question is, how do I differentiate between simple current deviation due to load changes or fluctuations and a fault driven change in current?

Is the difference going to be obvious because the rate of change due to a fault would be dramatically different in magnitude? and if so, how many folds should I expect the difference to be?

Thanks a lot in advance.

Dear all, hope you are keeping well at the moment.

I am trying to study an islanded microgrid with one grid-forming converter (GFMC) and several grid-feeding converters GFC supplying power to the island loads.

My query is how to calculate the size of the GFMC, I mean the minimum converter rated power that is required to keep the grid voltage/frequency stable. For instance, should this rated power be bigger/equal/a fraction of the installed power in the GFC/in the loads?

I would appreciate that you could provide some advice and if possible, recommend some papers that could serve as guidance.

Thanks in advance and BR!

I am working on a standalone DC Microgrid with PV and Battery with a load interfaced to a common DC bus through power electronic interfaces. The interface of battery is a non-isolated bidirectional DC-DC converter, through which the DC bus voltage is being regulated at a reference value(48 V in our case). Now under the case of variable irradiance and variable load, I am experiencing spikes in voltage especially at the instants of load changes. The filter design of the power electronic interfaces has been proper. Can someone help me in solving this problem?

The DC bus voltage variation is attached. The loading pattern is also attached.

In my current research, I need to build an experimental electricity microgrid and one important part is the battery as energy storage, but I need your recommendation of which battery solution or product (Sized 100 AH at 24V) together with its proper Battery Management System (BMS), preferably provides communication so that I can access information about battery's SoC, Voltage, Current draw and etc.

I am asking if anyone worked with a specific model that would recommend for my sepcific case. This will help me a lot, thank you in advance.