Seamless Transition of Microgrids - From Grid-Connected to Islanded Mode

Summary

In ETAP Software's webinar, Muhammad Zaree dives into the mechanics of microgrid systems, highlighting the critical aspects of seamless transitioning from grid-connected to islanded mode. The session focuses on developing efficient microgrid controls, the importance of resiliency, and utilizing green energy resources for critical loads during transitions. Zaree explains how microgrid control systems optimize the use of renewables through features like energy storage and peak shaving while adhering to grid constraints. A detailed examination of IEEE standards and the various modes of operation such as unplanned and planned islanding are also covered, along with comprehensive demonstrations showcasing the system's efficacy.

Highlights

• Microgrids provide resiliency by operating both connected to grids and independently in island mode 🌍.
• The microgrid control system utilizes energy storage to soak excess power and stabilize exports ⚡️.
• ETAP's microgrid solution ensures high-speed unplanned islanding using intelligent load shedding.
• IEEE's 2017 standard specifies three control function levels essential for microgrid controllers 📚.
• Digital twin technology allows simulation and real-time testing, ensuring microgrid system reliability.

Key Takeaways

• Microgrids can operate independently during grid failures, ensuring supply to critical loads ⚡️.
• Effective microgrid management can optimize renewable energy use and facilitate seamless transitions 🌿.
• Planned and unplanned islanding modes help manage microgrid transitions in various scenarios.
• IEEE standards guide the specifications and control functions of microgrid systems 📜.
• Demonstration of ETAP's digital twin technology shows real-time microsystem efficiency.

Overview

This insightful webinar by ETAP Software, led by presenter Muhammad Zaree, delves into the advanced functionalities of microgrid control systems. With a focus on smooth transitioning from grid-connected to islanded modes, the webinar highlights the role of microgrids in enhancing system resilience and efficiency. Zaree elaborates on how these systems provide critical load support using available renewable resources when the main grid fails.

Attendees learn about the microgrid control system's features, such as energy storage utilization for peak shaving and maintaining grid stability by controlling power export levels. A key part of the discussion revolves around planned and unplanned islanding, demonstrating how the ETAP microgrid control solutions implement these transitions seamlessly, ensuring continuous power supply to essential loads.

The webinar further explores IEEE's 2017 microgrid controller standards, which dictate the necessary control functions across various levels of operation. It emphasizes the innovative use of digital twin technology for real-time simulation and testing, showcasing its effectiveness in optimizing microgrid operations and ensuring reliability during critical transitions.

Chapters

• 00:00 - 03:00: Introduction The webinar titled 'Seamless Transition of Macro Grids from Grid Connected to Islanded Mode' is introduced by presenter Muhammad Zaree. The chapter begins with an exploration of the microgrid control system, emphasizing the role of the macrogrid controller. The focus is particularly on how these systems operate and transition smoothly between different modes of connection.
• 03:00 - 06:30: Microgrid Control System Overview The chapter provides an overview of the microgrid control system, specifically focusing on islanding transitions. It discusses both planned and unplanned islanding and how the ETAP microgrid control solution can facilitate seamless transitions between them. Demonstrations for unplanned islanding are examined, considering various cases. Additionally, it highlights the role of the microgrid controller in minimizing power at the point of interconnections to enable perfect planned islanding.
• 06:30 - 12:00: ETAP Microgrid Control Solution The chapter discusses the need for a microgrid control system, highlighting the microgrid's main attributes, with a focus on resiliency, which is the microgrid's ability to operate in both grid-connected and islanded modes. This feature is particularly important in the event of a grid issue.
• 12:00 - 21:00: Control Functions and Transition Types The chapter discusses the microgrid's ability to operate independently (islanding) to service critical loads using distributed energy resources, particularly green energy. It can sustain operations until the main grid becomes available again and can reconnect to the main system. A key feature of the microgrid is its capability to ensure continuous power supply during such transitions.
• 21:00 - 35:00: Unplanned Islanding Demonstration The chapter titled 'Unplanned Islanding Demonstration' discusses the integration of distributed energy resources and loads to create a grid-friendly microgrid. It highlights the role of microgrid control systems in ensuring compliance with interconnection requirements, such as preventing the export of power to the main grid at specific locations. These systems help in managing the interactions between the microgrid and the main grid efficiently.
• 35:00 - 45:00: Planned Islanding Demonstration The chapter 'Planned Islanding Demonstration' discusses the role of a controller system in managing the balance between renewable power generation and load demands. When there is excess renewable power compared to load demands, the system utilizes energy storage to absorb the surplus active power, preventing power export to the grid. The system is also required to support active and reactive power during disturbances. Additionally, the microgrid's efficiency is highlighted, with emphasis on how a microcontrol system facilitates this efficiency.
• 45:00 - 54:00: Digital Twin and Real-Time Simulation In this chapter, the focus is on the optimal utilization of renewable energy resources. This is achieved by incorporating energy storage which facilitates peak shaving, price arbitrage, and enhances the efficiency of renewables in a microgrid configuration. To ensure these attributes - resiliency, grid-friendliness, and efficiency - are cost-effective, a control system is essential.
• 54:00 - 54:00: Conclusion and Q&A The chapter discusses the concept of a microgrid controller, which is a supervisory controller that can be implemented either centrally or in a distributed fashion. It is typically situated near the microgrid point of interconnection or common coupling. The microgrid controller system plays a crucial role in facilitating communication within the microgrid infrastructure.

Seamless Transition of Microgrids - From Grid-Connected to Islanded Mode Transcription

• 00:00 - 00:30 welcome to etab webinar seamless transition of macro greets from greed connected to islanded mode my name is muhammad zaree and i'm your presenter today in this webinar first we're going to look at the microgrid control system we look at the role of mockergate controller and we specifically focus on
• 00:30 - 01:00 the eye lending transition functions planned and unplanned islanding look at the etab microgrid control solution and how it can facilitate the seamless transitions for unplanned and planned islanding we'll do a demonstrations of the unplanned islanding we look at different cases and then we'll look at the plan islanding and see how the mockerge controller can minimize the power at the point of interconnections to facilitate the perfect plan islanding and finally i'll
• 01:00 - 01:30 summarize this presentation so let's start with talking about the need of a microgrid control system so when we are talking about the microgrid there are several main attributes to it the first one is the resiliency and that's basically is the fact that the microgrid is able to operate in both grid connected and islanded mill and in case of any problem on the grid
• 01:30 - 02:00 side the microgrid is able to island itself and be able to operate or at least provide service to the critical loads and utilize the available distributed energy resources the green energy to feed the critical loads and sustain till the utility or the grid is back or main grid is back and be able to reconnect back to the system another key attribute of the microgrid is that the microgrid
• 02:00 - 02:30 concept makes the combinations of the distributed energy resources and loads together be more grit friendly okay there are typically several requirements at the point of interconnections of the micro grid to the main grid and uh what the mockery control system does it basically meets those requirements and makes sure that the microgrid is grid friendly let's say that there's typically a constraints on that a microgrid is let's say not supposed to export any power to the grid at certain locations so the job of the democracy
• 02:30 - 03:00 controller system is to make sure that in case of the excess of the renewable power as compared to the lows it utilizes let's say the energy storage to absorb the extra active power and make sure that there is no export power to the grid there are also requirements on the active reactive power supports during the disturbances to the system asthma another aspect of the microgrid is the efficiency typically a microcontrol system allows
• 03:00 - 03:30 to optimally utilize the renewable energy resources typically by having energy storage you can do a peak shaving you can do price arbitrage and you can make a mockery more efficient you can make the usage of the renewables more efficient in a microgrid concept now in order to make let's say these three attributes resiliency grid friendly and efficiency to be cheap a control system is required and typically uh the key assets of the
• 03:30 - 04:00 this control system is a microgrid controller so what is microgrid controller mockery controller is a supervisory controller that can be physically implemented in a centralized or distributed manners in a typical configuration microgrid controller system is realized by a microgrid controller that is located close to a microgrid point of interconnections or point of common coupling now this controller communicates with the
• 04:00 - 04:30 local controllers of renewables energy storage uh conventional generations loads and uh directly or indirectly uh controls those dispatchable assets as well as it uh communicates with the point of interconnection assets uh again directly or through some other meters like circuit breaker switches and tries to basically achieve all those three main attributes that we discussed in the previous slide
• 04:30 - 05:00 and make sure that it can operate in both grid connecting the islanded and also it makes that mockery grid friendly as well as we can do optimizations to make sure that we are running the renewables efficiently in the system macro grid controller specifications so ieee issued in a standard in 2017 2030.7 which is there which is a technical specifications and requirements for microgrid controllers as per this standard three levels of
• 05:00 - 05:30 control functions are defined for the microgrid control system level one control functions are lower level functions that are supposed to be implemented at dr's loads or device level as you see that the voltage and control frequency real and reactive power control the device specific functions level two control functions are the ones required at the microwave point of interconnection level to facilitate transition between grid connected and
• 05:30 - 06:00 islanded modes of operations as well as rules to let's say dispatch microgrids the level three contour functions are higher level functions that perform supervisory control a mockery controller can typically provide level two and level three functions uh together some of the level twos not all of them uh let's see in this list you see that there are supervisory uh distributed management system operator interface grid and
• 06:00 - 06:30 market optimal dispatch communications and uh typically a typical mockery is supposed to wash some level of optimal dispatch it does some level of a scatter for that micro grid and communication as well as per ieee 2030.7 standard there are four possible transitions unplanned islanding it's shown in this graph as t1 plan islanding t2 reconnect d3 and black star t4 let's quickly go
• 06:30 - 07:00 through each one and try to understand what each transition is so basically if a microgrid happens to be in an islanded mode either due to trip of the circuit breaker due to the fault next to their point of interconnections or due to loss of greed at certain point and back feeding from microgrid to the grid typically voltage drops and things like that that
• 07:00 - 07:30 we realize at a point of interconnection that actually the grid support is lost so we immediately trip the second breaker at the point of interconnection so all these conditions are typically the result in the islanded case uh and and typically if there is no island request ahead of time that's considered as the t1 which is an unplanned islanding uh in contrary if uh the there is a need to do let's say some maintenance at the
• 07:30 - 08:00 certain point uh certain part of the utility and we want to go to the islanded mode that then there could be a request a microwave control system and then the microwave control system prepares democracy ahead of time and at the time that is supposed to go islanded it makes a very smooth and perfect islanding to minimize the disturbance to the system which this calls plan islanding which is the feature okay when microgrid runs in the islanded mode and then the utility comes back and the
• 08:00 - 08:30 voltage remains stable for a certain amount of time the frequency is good the harmonic content and everything is good at the utility side then the mockery controller can automatically reconnect the microgrid back to the system and bring back the non-critical loads or it can be through the confirmations and requests by operator to reconnect back to the system also anytime that microgrid blacks down
• 08:30 - 09:00 whether the on-plan is not successful uh or the reconnect events and that's not successful we go to the blackout and then what happens is that either we start start the assets one at a time based on a very unique or customized scheme to bring the assets back to the system and energize the microgrid or if the utility is available and the reconnect originally was not successful we do a cold load pick up we
• 09:00 - 09:30 energize the micro gear from the utility size and then we bring back the asset one at a time so basically this is kind of a different type of the transitions let's quickly take a look at each one at least the ones that are important for this webinar so the first one is an unplanned islanding so the first thing is that we detect the island conditions we create the island and then set local controllers and protective devices appropriately and then execute required planned action
• 09:30 - 10:00 tree plan actions such as load sheddings or if you want to do black history trip all the assets and do the black stars and transitions to the city-state islander dispatch mode okay so we go a little bit through the etap demonstrations to understand how the unplanned islanding works what are the details involved now plan islanding is typically a mockery control system receives the island in command and tries to balance
• 10:00 - 10:30 before balancing load and generations if it has time if it's way ahead of time it tries to prepare the microgrid for the islanded operations charging a battery make sure that it has good amount of charge to sustain a muggy for a long time then it comes to a few minutes prior to the island into balance load and generations typically it tries to increase the power of the battery the discharge power
• 10:30 - 11:00 to minimize the import power if requires to start a generator starts a generator then if it requires a load shedding if there's a significant amount of input power does the load shedding so it brings the balance in both active and reactive power and then also sets the local controllers and protected devices if protection system needs to adjust and then it creates the island and then transitions definitely to the islanded mode of operation now black start again is as we discussed this
• 11:00 - 11:30 standard doesn't define anything as specified as it says that it's unique to each microgrid and keep in mind uniqueness means is expensive means that you need to have a special design development and test so if we do a very good job on the unplanned islanding uh what happens is that we can avoid the black start okay so as we go through the today's etap solutions for the microgrid and then the simulations then the
• 11:30 - 12:00 demonstrations we realize that if we do very good jobs if we do intelligence and dynamics on planet eye lending as itap provides we can avoid this black star and this unique expensive uh design and development that is required for the microgrid when you when we are talking about the unplanned islanding uh typically in a micro environment we are importing power before loss of grid okay so what happens is that the moment that we lose the grid typically immediately
• 12:00 - 12:30 voltage drops typical uh renewable resources the dr's there are typically control current source and as the load drops what happens is that as the grid uh drops we are injecting less current to the load so the voltage immediately drops okay keep in mind that the ders at least the ones that produce a good amount of active and reactive power they
• 12:30 - 13:00 provide higher reactive power injections during the voltage drop so the drs start to inject reactive power and bring the voltage back up when you are talking about the microgrids and specifically we are talking about the loads we have to keep in mind that the type of the load drastically impacts the performance of the microgrid when we lose the grid and voltage drops if you're dealing with static loads what happens is that the active and
• 13:00 - 13:30 reactive power consumed by the static loads drops drastically okay because these are impotent space and the power depends on the correlates with the vs score okay so voltage drops power drops even more but if it's a motor loads is a different story motor loads typically they're like a constant power uh active power and if the voltage drop they actually absorb more reactive power so it's a different characteristic so
• 13:30 - 14:00 modeling knowing then how the load behaves is very important on the transients and be able to have a successful unplanned eye landing okay so when we lose the grid and voltage drops depending on how the load behaves and how much renewables can provide reactive power the frequency varies means that it may go up and down it's not just always because we lost the input power we lose every frequency door
• 14:00 - 14:30 this is not like a synchronous machine system a large system that the loads typically uh does not change that much but here because load depends significantly under voltage the frequency actually may go the other way around too at certain points because voltage drops power may drop even more frequency may actually go up for certain point but as the voltage builds up by injecting reactive power then the
• 14:30 - 15:00 basically active the load goes up and then the frequency drops so it's a little bit have a different dynamics and behavior than a regular uh system now the other thing that is very important to to consider when we do the unplanned islanding is the right through capability typical um grid codes mandates renewables dr's to right through the fault for at least 150 milliseconds so if there's a fall and
• 15:00 - 15:30 voltage even drops to zero typical says that the renewables must sustain again not all renewables renewables above a certain size has to sustain at least 150 milliseconds or if the frequency varies within uh several percentage let's say that here as you see in this one if you look at let's say the uh let's look at the tighter one here okay see that the frequency drops about two plus minus two hertz is still you're gonna sustain about one seconds or more
• 15:30 - 16:00 means that the dr should not thrip if the frequency goes like uh two her plus or minus for like one seconds or two seconds so so you see that voltage is a higher kind of stricter requirements but what does that mean is that if your microgrid goes to the unplanned islanding we as a mockery controller we should or microcontrol system should have unplanned islanding pre-plan so be able to do all the load
• 16:00 - 16:30 shutting switch into grid forming and everything before 150 milliseconds to make sure that you do not lose your renewable supports your energy storage your uh vein or solar whatever green energy we have so it's very important to have a very high speed on plan islanding now let's look at the eta mockerge control system but in this webinar we will focus mainly
• 16:30 - 17:00 on the key feature of our solution that allows to have a high speed dynamic unplanned islanding if you're interested to learn more about the etab micro grid you can always go to the etab website and in the microgrid page there are links to other webinars that talks in general about the etab microgrid solution so this webinar will focus mostly on the in on the islanding transition
• 17:00 - 17:30 so etab micro u control solution include mainly etab microgrid controller which is a supervisory controller and a gateway okay etab ice gateway and this ice skater i will discuss has two roles and with this dual or two components that one runs at very high speed and the other one that runs at the lower speed we can achieve both higher
• 17:30 - 18:00 speed uh unplanned islanding but at the same time doing a dynamic sophisticated logics to be able to do everything all the way from planning the unplanned islanding strategy as well as all the way to optimizations do advanced calculations for democracy be able to do stuff like forecasting so in a typical solutions that we have these two components as i said we have a gateway and we have
• 18:00 - 18:30 a mockery controller one of the roles of this gateway to understand is that is typical when we are dealing with a microgrid we are dealing with different assets that may communicate with different protocols one of the jobs of the gateway is to be able to communicate through different protocols 650 dmp3 modbus and all other common protocols and even it has a hardwire connections the analog inputs
• 18:30 - 19:00 or digital inputs and outputs uh and convert everything to a unified kind of protocol at this point dmp3 and soon it's going to be modbus 2 to etap microgear controller the second important job of this gateway is that it has a built-in plc that it runs at the few milliseconds execution rate and it can do things fast let me go to the next slide actually it shows uh how we do the uh highest speed
• 19:00 - 19:30 on planet ending so a mockery controller typically runs at every few seconds okay and it looks at the active power control reactive power control but at the same time it also devised strategy for unplanned islanding every few seconds okay it looks at how much renewables we have in the system how much battery capacity state of charge we
• 19:30 - 20:00 have how much loads we have it knows about all the priorities of the loads or characteristics it knows how much power we are importing from the greed uh it knows about the forecast of the system so based on that at every few seconds it says that what if i'll go to the islanded month what if i lose the grade it comes with the intelligent dynamic strategy for islanding and writes that a strategy
• 20:00 - 20:30 in forms of the potential commands for different assets in this gateway so there will be registers per each der and the loads that says that in case that islanding happens what each asset should do potentially then there is a small interlock between the relay at the point of our meter at the point of interconnections either to the hardwire or to the goose message or something of a fast nature to this plc
• 20:30 - 21:00 within this gateway and the moment that things gets triggered it will immediately sends a command to the asset on things that needs to happen okay so that's one way to do it that the moment things happen typically goose message few milliseconds comes to the gateway and through the goose message it also sends command to the asset few milliseconds and be able to within let's say two three hundred milliseconds to command the assets to do
• 21:00 - 21:30 the load shedding and stuff typically circuit breakers of the dr's also take time to trip the loads but we are able to within less than 150 milliseconds to be able to bring back the voltage up to avoid any undesired tripping of the renewables and dr's from the system the other way to do it is also is this logic if the dr's have a controller that they can be in some extent program this small logic can be actually
• 21:30 - 22:00 interlocked with the por can be implemented at the dr level as well and the load level sometimes that in case that typically what happens is that you have a load controller or relay so you can customize some logic here and have intellectual point of inter connections and the mockery controller can write to the relay at the for the loads to say that if there is a loss of what needs to trip and also for energy storage if they have a programmability
• 22:00 - 22:30 or something we can send a command that in case that we lose the grid automatically switch from grid following to grid for me okay so this architecture having the two components allows one running at few milliseconds and one at few seconds allows to get the best of both worlds have a sophisticated logic that here in the mockery controller can do advanced stuff and dynamically based on the system status updates the schema for the for the islanding and also have a plc based
• 22:30 - 23:00 approach with a few milliseconds to immediately react and island assist them do the load sheddings and create falling to forming to sustain the microagree let's look at the one more time summarize what we said the mockery controller dynamically devised high lending strategy elixir the available distributed energy resources at their characters it looks at the load priorities and their characteristics user may have some settings and priorities as well that can set it up
• 23:00 - 23:30 and then it sets islanding registers in gateway so that the logic indicator is very simple there are a bunch of uh predefined registers by the mockery controller at the gateway level and there's just an interlock that the moment we see that the grid is lost we immediately dispatch those commands to the asset okay so we send island and transition commands upon grid loss very simple now for demonstration today we want to
• 23:30 - 24:00 demonstrate unplanned islanding and plan island in a typical micro grid control environment in order to do a good demonstrations you need to have a lab with the typical real-time digital simulator then you have your hardware you connect them together you have your mockery model in a real-time simulator and then you have your mockery controller you run scenarios and looks at the performance of the system that's what a typical
• 24:00 - 24:30 mockery control solution does but in etab if you look at our previous webinars on our microgrid solution we use a digital twin concept means that our mockery controller has a identical digital twin let me go here it has an identical digital twine that can be used in the etf simulation environment and that basically anything we want to
• 24:30 - 25:00 uh test develop enhance do evaluations we can do in the simulation environment we make sure that it works and then this digital twin gets deployed into the box this digital thing is not the model is the actual code that runs inside the box runs actually the software environment is a cross-platform uh uh basically uh technology that runs in both linux and windows and this allows
• 25:00 - 25:30 us to use it for design and feasibility study we can do evaluations test it in front of the user we can use it for sizings of the assets and we can do optimal settings and also we can use it to our develop and test as a developer and tester in the in our company so that's another great advantage that we actually develop the digital twin tested once we happy we deploy and test it in the hardware okay let's now go to the demonstration
• 25:30 - 26:00 now let's look at a quick demonstration so here i have a simple microgrid uh i have about uh 1.2 mva wind i have 1.2 mva solar i have 1.2 mva battery with 2 megawatt hour capacity i have about 4 mva load and then the good thing about using etab for a microgrid solution is that eta provides
• 26:00 - 26:30 the good primary controllers for microgrids so here you can see that all the basically parameters of the control system a generic model that we have for our primary controllers are based on a web second generation model and here you can set all the parameters for p control q control and if you have a grid forming it provides also outer control loop and inner control loop for the grid forming as well so
• 26:30 - 27:00 a very tested validated model is available for the grid falling and informing performance typically it's used for energy storage rather than use for the pv for pv typically if you use just the or views grid following then it has also the right true capabilities low voltage right through high voltage right through low frequency right through high frequency right through now if you have a black box model also you can use a black box
• 27:00 - 27:30 model instead of the generic model but typically when it comes to the mockulgi controller performance evaluations uh especially uh if you're looking just look at the typical active reactive power control using the generic models are fine if you want to do a certain let's say a plan or um uh um unplanned islanding sometimes it's better uh the designer says to good use generic model but at the final stage if you want to validate everything you can use also a black box
• 27:30 - 28:00 model so we have the model for the renewables we have models for energy storage again where you can define basically the operating parameters the minimum charging discharging the capacity stuff so here i have my energy storage and then i have the micro g controller you see that we have a digital train of every uh device so we have this controller element that connects to a
• 28:00 - 28:30 dlr which is a kind of a black box model of etap microgrid controller as you see here is that we have all those uh required functions for a mockery control system we have the forecasting active power you can do rule-based dispatch economic dispatch each one again you can define the optimizations problem or in the rule base you can define what are your rules in terms of the import and export power pick shaving stuff and then you have your reactive
• 28:30 - 29:00 power control that you can do uh voltage or reactive power power factor control at the point of interconnections of the microgrid you can define which assets to use as a priority whether to use energy storage space pv second capacitor statcom you can use all those devices there are other functions but today we're gonna first focus on unplanned islanding and then plan islanding so the the first functions that we're gonna look is the uh uh on plan eye landing
• 29:00 - 29:30 let me go to the case uh that i'm gonna show first so we're gonna go to the case uh this case let's go to the microgrid controller one more time go to the unplanned islanding so uh in this on planet ending i'm defining that my unplanned eye landing is enabled and uh we're gonna have the battery as a grid former device uh the threshold for blackout is 70
• 29:30 - 30:00 means that if the import power is more than 70 of the the entire load in the system uh and maybe it's better to directly go to the blackout rather than try a seamless islanding we're gonna keep ten percent reserve margin for the going to the islanded mill so means that uh we need to shed a little bit more load or have more generation assets available to maintain the system there could be some stabilization times means that
• 30:00 - 30:30 uh in order to devise the strategy for islanding we have to have a first stable system and then we devise a strategy we send it to the gateway and in the gateway evade the moment that we detect the trip we go and act uh upon it okay now we are giving one second for the seamless islanding if beyond one second system doesn't come back to normal we go to the blackout okay so this is a simple settings for the unplanned island and keep in mind that we have the loads that's defined in the
• 30:30 - 31:00 systems there's circuit breakers and then we have the load priorities that uh in what priority we're going to shed loads let's say that lump 5 uh load in this system is the one that's going to be shut first and then num 4 and so on and so forth we have the ingress currents this is typically for the black historic but we have it here we also have curtailment priority means that in case there are microgrids that allow to export power to the system
• 31:00 - 31:30 and if you have excess of generations we can actually rather than do load shading we do curtailing of the sources okay of the system let's quickly go ahead and run one case and take a look at the performance so i'm going to go ahead and run the islanding high load let me go ahead and run this case i'm running trains in a stability simulation for i think few seconds and
• 31:30 - 32:00 what we are expecting here is that at the time zero as you see here we are importing about 1.64 megawatt and 0.647 megavore so we are importing power from the grid and then at time uh 11 seconds at time 11 second just before default okay let me just go before the loss of the grid still we have that 1.65 mega volt 0.646
• 32:00 - 32:30 i'm giving 10 seconds or 11 seconds of simulation for a reason that i will explain so nothing is almost happening system is running as it is in a city-state condition and then when the we lose the grid okay once we lose the grid you see that immediately voltages starts dropping and then uh the microgrid controller ahead of time program our gateway to trip a certain load based on the power balance in this
• 32:30 - 33:00 scenario you see that it trips the lump 5 circuit break here and it sustained the system okay before we go into the details of how we do the saturns how this works so let's first plot the voltage magnitude okay as you see here i have about uh i have 11 seconds that there is a trip and uh as you see here is that immediately voltage drops but as we do the load shedding voltage comes back and then the
• 33:00 - 33:30 battery in grid forming tries to maintain the system and as you see voltage comes back to the pre-fault or pre-disturbance level in this case and the key important thing here is that as you see in this graph uh with less than 150 milliseconds we were able to bring back the voltage and voltage didn't drop that much also because we were importing only 1.6 megawatt voltage didn't go even below 70 percent so we managed to bring back the voltage keep in mind the renewables also
• 33:30 - 34:00 inject reactive power in this case now let's look at what happened in a little bit more detail here the microgate controller execution rate is five seconds means that mockery controller for this case runs every five seconds it runs at time zero it runs at time five at time ten it looks at the system conditions and based on that says that okay i am importing 1.64 megawatt my battery is not doing anything but it
• 34:00 - 34:30 can generate one megawatt power so if i go to the islanding conditions uh i am lacking 64 megawatt okay we need also some reserve margin 10 percent as well which is around uh some some kilowatts here okay so what it says that okay i have a load let's say lump 5 which is right now at the about point seven five so if i shut this load 0.75
• 34:30 - 35:00 okay and i have one megawatt here i have enough power to accommodate or compensate the loss of the grid that's why it only programmed the gateway to only shed basically lump five that's enough to sustain the system so the other thing that it does that it's discrete battery if i go to the battery this battery has the command setup up to
• 35:00 - 35:30 communicate to the remote control so this battery is communicating to this gateway if i go to this gateway and go to the associated device list you see that this battery is controlling and monitoring this uh battery controller bes controller here and the moment we do the islanding strategy we define discrete forming source battery and our loads so what happens is that the mockery
• 35:30 - 36:00 controller commands the gateway and gateway commands the battery and the loads to actually shut and also better to switch to grid for me so you see that you have a full digital twin of all the primary controller secondary controller the relay at the point of interconnection the gateway and everything so what this does it allows to maintain the system let's also look at the bus frequency very quickly as well as you see here that we have the bus
• 36:00 - 36:30 frequency too so uh as the voltage drops if you remember what i mentioned that sometimes when you lose the grid the power drops the input power drops but what happens is that because of the voltage drop the load drops also significantly at one point so that helps actually to make a balance in sometimes a mockery again depends on the load but rather than frequency going down it actually goes up in this case
• 36:30 - 37:00 okay in this case actually it's going up but the moment that inverters start putting more reactive power and the battery starts to inject more power the voltage comes back loads come back but the load shedding helps to shut the load provide the power balance and bring back the frequency to the case now if i also plot the my powers here you can see also the powers that i have let me uncheck this and
• 37:00 - 37:30 uncheck all and plot the megawatt two and you can see also the uh that the load and generations here that you you had the load at about this much because we shared and the battery went all the way from the zero up to a certain amount to compensate what is needed for the system okay and the maintain the reserve margin as well if you look at the battery is at a certain value to maintain the reserve margins of the system okay so this one case that uh i'm
• 37:30 - 38:00 demonstrating now go to the another case where in this case i have lowered my pv generation let's say that it's early morning or late afternoon or evening and i have lower pv high load and what's going to happen is that if i run this case so again we are running the similar case and this time we are going to look at the
• 38:00 - 38:30 point of connection power and see how much we are importing so in this case actually is 2.6 so if you are actually importing more power from the system mockery controller looks at how much power is available to import and how much power is available by the sources and the loads and tries to do the load shedding so if we go here and look at what's happening we lose the grid and this time macro g controller is going to shut three
• 38:30 - 39:00 lows keep in is is not the mockery controller shedding the low is the gateway shedding the loads okay is the market controller that programs that give a ahead of time probably five seconds earlier maximum five seconds that in case we lose the grid what needs to happen so gateway is a little bit just dummy just it looks at the trigger and it applies the command the microgrid controller is the one that depending on the import power and the availability of the resources says what needs to happen so it dynamically updates the load
• 39:00 - 39:30 shedding logic and as you see here again if i go to my bus again look at my voltage and frequency you see that the microgrid controller the combined ether solution be able to maintain the voltage and frequency within the limits and we didn't lose any pv or anything from this system right now you see that my communication delays are little but if you want to get more communication delay at the circuit breaker trip times and things you can always go here and add the communication delay and and see the
• 39:30 - 40:00 performance at that 20 30 milliseconds communication delay and see how the system behaves uh another important function in a micro that microgrid controller is supposed to provide is the plan islanding in the plan i lending what happens is that typically a system operator or a distribution system manager sends a command ahead of time to the mockery controller and says that i want to i land this microgrid in
• 40:00 - 40:30 let's say four hours from now and i want to maintain it for two hours and what happens is that the microcontroller is going to slowly brings down the active and reactive power at the point of interconnections make sure that the power is balanced and then disconnect the circuit breaker for this microgrid typically the the one that i'm studying here the reactive power is not that much and we are mainly focusing on active power
• 40:30 - 41:00 balance now again in etab environment the commands always comes through the gateway so in our digital twin for the gateway we created already a case that user can say that i want to send some commands of plan islanding emulate the plan islanding commands so we say that in the first day of the simulations at uh eight o'clock in the morning so we are running 24 hours of simulation at eight o'clock in the morning uh zero minutes and zero seconds we are
• 41:00 - 41:30 going to send a request for plan islanding and we said that we want to do plant islanding at four hours from eight which would be 12 hours 12 o'clock noon and we want to have a two hours durations so what the mockery controller does it looks at the forecast of the loads generations and it looks at the seed of charging the battery and does some calculations that in order
• 41:30 - 42:00 to maintain the two hours of the islanded operation uh how much battery needs to be there how much low shedding is needs to happen uh what assets needs to bring up if you have a backup diesel generator and things like that so in this case i'm running a scenario for 24 hours okay let me run this scenario that i've prepared already so plan islanding we are going to run time domain load flow in this scenario
• 42:00 - 42:30 24 hours eight o'clock request 12 o'clock is gonna bring down the power but ahead of time also it's going to charge the battery okay so we ran 24 hours and let me plot the power active power of different assets as you see here that uh recent with the moment that we send the request okay we already had our battery charge in somewhere here okay
• 42:30 - 43:00 uh the battery had full charge uh or enough charge to sustain the two hours so the key point is here few minutes before if you're going to the islanded mode what the mockerge controller does is gonna actually start let's say the battery brings up the power of the battery and this results into bringing down the active power at the tie cable so this is if i just remove the pv and keep the battery here you see that
• 43:00 - 43:30 as the battery goes up the power comes down and the moment that it reaches to certain level it has some depth band around 100 kilowatt the next time a step which is about or five seconds from now it can actually do the islanding so this is another important functions of a microgrid that whenever we want to have a planned uh seamless islanding we can use a plan island so far what we have done was a pure simulation using the digital twin
• 43:30 - 44:00 of the microgrid as well as the digital twin of the microgrid controller we ran bunch of simulations and we showed that how the unplanned islanding or planner landing works in a simulation environment now let's take this to another level the next level is be go ahead and look at this microgrid controller we can we have a part that we can define the
• 44:00 - 44:30 settings of this microgrid controller so let's imagine that i want to test this in a real time with the real term digital simulator so how it's going to be the entire system the entire system is going to be modeled in the real-time digital simulator and then the my mockery controller is going to be a hardware connected to the communication right now i have my mockerge controller at the ip address of 10 10 10.172
• 44:30 - 45:00 and this computer that we are working on right now is at the ip address of 10 10 0 45. etab has a dmp3 interf dmp3 interface that can uh put the data out all the measurements that microgrid needs and the mockery controller hardware and this ipl address has a the mp3 client that can grab those data process them the same logic that runs in the digital trend and sends the output
• 45:00 - 45:30 back to the microgrid so what we are going to do here as you see in the communication sections we have the ip address of this device we are going to use the twenty thousand one as the port number for dmp3 it has source id uh destination there's some of the default numbers i'm not going to touch so the first thing we're going to do we're going to deploy what the deploy does it creates a package which is a mgc file it creates a package of all the logics which are dll of the
• 45:30 - 46:00 digital twin plus all the settings the connectivity the network informations and put them in a package and we can go ahead and upload that into our microgrid controller so we go here and say upload this controller deploy upload so all the logic settings everything is now moved uploaded into the box in few seconds done so you can go ahead and we can look at the settings of the microgrid controller okay different settings that we have
• 46:00 - 46:30 here now once that's done let's come back here and say that i've created a steady case with a little bit longer simulation time i have about 180 seconds i want to give more time to be able to go on the real-time side to be able to go through the different dashboard and see how it works but after two minutes 120 seconds i am going to uh we have an event to trip the circuit breaker at the point of interconnections and see how the microgrid controller
• 46:30 - 47:00 actually transitioned this microgrid from grid connected to the islanded mode so we looked at the static case the other thing that we need to look at here is that we have a setting here simulation mode so if it is normal it just runs the pure simulation okay it runs a pure simulation if i run a tester mode it runs it in a real-time manner but the logic is not getting executed here the data is transferred over communication to the
• 47:00 - 47:30 hardware is like a hardware in the loop and hardware processing it and sending the output back to the eta that where the system is okay now this is um it was faster than real time if you run this system it's gonna run less than 180 seconds so this means that for this size of the system a little bit even larger we can always go real time keep in mind we are running every one millisecond here in the transient stability but the data gets exchanged over dmp3
• 47:30 - 48:00 with the speed of order with the resolutions of the microgrid execution rate every five seconds so data goes every five seconds to the basically uh dmp3 we can control that we can go a little bit even faster we can go even every one second to the dmp3 even though mockery controller runs every five seconds okay so let's do that so we are in the tester mode right now in the tester mode so what i'm gonna do i'm gonna go ahead and run this
• 48:00 - 48:30 so it's supposed to take 180 seconds okay now let's go to etab let's go to our microgrid page let me refresh this page you see that we are good connected grid connection is on we have about 2.60 megawatt input from the grid frequency is 50 hertz i have about 98.9 percent voltage at both sides of the grid and microgrid okay we can look at
• 48:30 - 49:00 our energy storage at this point we have we have a command but mockery is in advisory mode means that it doesn't send any command you see that the microgrid doesn't charge if i go here and say that i want to go out of the advisory mode and come back to energy storage in a second let me increase the resolution here in about a second or so we are going to be switching to the uh enabled mode so mockery controller sends the command of 103 and we are
• 49:00 - 49:30 discharging 103 and we are just actually discharging 103 in the system too now if we go to the p i have unplanned ironing page and in this page you see that at this point it says that if we lose the grid you see that this gets updated every five seconds if we lose the grid we are supposed to shed three lows very similar to what we saw in the simulation and battery has to go to grid forming now in about a few seconds once we reach 30 seconds when we reach to the two
• 49:30 - 50:00 minutes microgrid is going to switch to the uh islanded mode and because this information is already transferred to the gateway in the simulation it knows what to do so it doesn't need to wait okay so we go now to the macro grid and let's look at the micro grid here so in about few seconds we should go off let me just in reduce the resolution to uh
• 50:00 - 50:30 the resolution here so we see that we are in the grid connection on and in both few seconds we should transition to off there you go now we are in the islanded mode things happens very quickly okay in less than a second system gets back to normal you see that both side frequency or 50 system didn't collapse okay now let's go and take a look at the load look at here you get here i have three loads that they lost power okay only two
• 50:30 - 51:00 loads have power so we have done a successful load shedding here microgrid is in islanded mode and we can look at what's happening with energy storage okay you're not sending any more command to the battery battery is in the grid for me and the power gets determined by the system voltage and frequency no more command and soc is going to drop at uh uh associate at this point we are exporting power we are exporting power so soc is
• 51:00 - 51:30 going to go down so now let's go back simulation is done we just ran for three minutes and let's look at the performance of the system here we did the load three load sheddings and if i go and plot the bus voltage if you remember the simulations you exactly get the similar performance okay system comes back to normal so with that we showed that actually how nicely you can use etab as a real-time digital simulator and how easy is that from the
• 51:30 - 52:00 software simulation go all the way to the hardware simulation now with that let me go back to uh my presentation and summarize this this in this webinar first we introduced mukki control system and explain the important role of micro grid controller we focus mainly in this webinar on plan on unplanned islanding and we discussed that in order to have a successful unplanned islanding it is important to have a high speed dynamic
• 52:00 - 52:30 eye landing strategy to succeed seamless islanding etab has used this concept of a kind of intelligent load shedding where a controller devises a kind of a server or a higher level supervisory device comes with the strategy using all the informations in the system dynamically every few seconds and kind of programs or fines and tunes at plc
• 52:30 - 53:00 or high speed device that's ready that upon a trigger which can be a great loss detections or circuit breaker trip immediately acts and does let's say a load sheddings or grid forming battery mode chains and things like that now we talked about it ab solution and we did two sets of demonstrations number one we use the pure simulation the digital twin of the macro grid and digital twin of the microwave controller and we showed that you can do lots of
• 53:00 - 53:30 simulation testing fine tuning and evaluations of the systems when we were happy with the performance we deployed that the controller digital twin and we uploaded into the microgrid controller hardware then we started at testing a mode in etab and ran etab as a real-time digital simulator with the dmp3 server and microgrid controller is a dmp client so data went over the communications from one
• 53:30 - 54:00 pc to the mercury controller hardware the logic got executed and we saw that uh the the unplanned islanding strategy in real time and once that event happens with the grid loss we saw that how the gateway knew what to do based on the micro grid strategy or advice ahead of time and did the load shedding switch the battery to grid forming and maintain the system so with that i'm done with my presentations and thank you for your
• 54:00 - 54:30 attention and i'm more than welcome to any question [Music] [Music]
• 54:30 - 55:00 you