Generation Dispatch Control Center

Generation Dispatch — All About the Balance

The large-scale dis­tri­b­u­tion of elec­tric­i­ty comes with a unique chal­lenge: Since elec­tric­i­ty is not being stored in grid-scale quan­ti­ties, elec­tric­i­ty sup­ply and demand must be bal­anced at any giv­en time. In oth­er words: Gen­er­a­tors must always feed the grid with new pow­er at the same rate it is being lost and con­sumed. This chal­lenge is becom­ing hard­er due to the inter­mit­tent nature of renew­able ener­gy sources and its uneven geo­graph­ic dis­tri­b­u­tion. For this rea­son, grid oper­a­tors must increas­ing­ly invest in infra­struc­ture and ancil­lary ser­vices to coun­ter­act these trends.

Many fac­tors such as weath­er, time of the day or some­times even a sports event influ­ence the elec­tric­i­ty con­sump­tion sched­ule of the cus­tomers, caus­ing the grid load to fluc­tu­ate over the day, the week, and the year. In order to match sup­ply and demand, util­i­ties try to pre­dict the load for dif­fer­ent time peri­ods and pur­chase this pow­er up to a day before it will be con­sumed. As the con­sumers’ pow­er demand con­stant­ly changes and an exact pre­dic­tion is not pos­si­ble, util­i­ties can turn to the spot mar­ket and dif­fer­ent pow­er reserves and ancil­lary ser­vices to adjust the amount of elec­tric­i­ty pro­duced by var­i­ous gen­er­a­tion plants.

If the required load is high­er than what the gen­er­a­tors are cur­rent­ly pro­duc­ing, the fre­quen­cy of the elec­tri­cal grid drops below the desired 50 Hz (in the US & JP 60 Hz). The fre­quen­cy must be sta­bi­lized with­in cer­tain lim­its to pro­tect con­sumers (such as tools and devices at home) that are sen­si­tive to fre­quen­cy changes. Grid oper­a­tors (gen­er­a­tion dis­patch­ers) must then increase the pow­er out­put of cho­sen gen­er­a­tors, or bring an addi­tion­al gen­er­at­ing unit on line to get the fre­quen­cy back to 50 Hz. The oppo­site case occurs when gen­er­a­tion out­put exceeds con­sumer load. The sys­tem fre­quen­cy increas­es above 50 cycles and grid oper­a­tor must decide which pow­er gen­er­a­tion out­put needs to be dis­patched. Alter­na­tive­ly, ancil­lary ser­vice providers and util­i­ties can also import elec­tric­i­ty or dis­con­nect large loads when the sup­ply falls short and vice ver­sa in the oppo­site case. The pri­or­i­ties that deter­mine, in which order and to what degree gen­er­a­tors get dis­patched vary between legistlations.

Further Advantages with iGrid T&D

Further Advantages with iGrid

• ICCP / TASE 2 (IEC 60870–6) for com­mu­ni­ca­tion between con­trol centers 
• All-in-one plat­form, oper­a­tion, mon­i­tor­ing and real time con­trol of both gen­er­a­tion plant and elec­tri­cal infra­struc­ture (sub­sta­tion and grid-con­nec­tion) in real-time.
• Advanced PPC mod­ule with pow­er­ful algorithms
• Bid­ding and expect­ed gen­er­a­tion module
• Same, cus­tomiz­able envi­ron­ment for all actors and all lev­els, from gate­way to con­trol center
• Inter­nal PLC based on IEC 61131–3, eas­i­ly pro­gram­ma­ble with our free iConf tool
• High­ly flex­i­ble, mod­u­lar and scal­able solu­tion, adapt­able to any sys­tem requirements/ net­work topology
• Access from any­where via web browser
• Full inter­op­er­abil­i­ty in any elec­tric facil­i­ty –col­lect data through any meter­ing pro­to­col pro­to­col (incl. IEC 61850) and map it to IEC60870‑5–104 or DNP3

Generation Dispatch Control Center

What’s Behind It

Through the appli­ca­tion of Auto­mat­ic Gen­er­a­tion Con­trol (AGC) algo­rithms, which take into account gen­er­a­tor behav­ior and local fre­quen­cy read­ings, dis­patch­able gen­er­a­tors can autonomous­ly pro­vide grid-bal­anc­ing ser­vices with­in a few sec­onds, which is referred to as pri­ma­ry fre­quen­cy response. Some grid oper­a­tors and util­i­ties demand from all pow­er gen­er­a­tors some degree of pri­ma­ry fre­quen­cy response.

Sec­ondary fre­quen­cy response describes the ser­vices that are pro­vid­ed after a few sec­onds to sev­er­al min­utes and are usu­al­ly trig­gered by direct com­mands and set-points sent from the grid oper­a­tor to the gen­er­a­tion plant. These com­mands must be inte­grat­ed and inter­pret­ed by the AGC of each par­tic­i­pat­ing pow­er plant.

For longer time peri­ods, grid oper­a­tors make use of the oper­a­tional reserve, which can be dev­id­ed in a spin­ning and non-spin­ning /supplemental reserve. The spin­ning reserve con­sists of gen­er­a­tors, which are capa­ble to tem­porar­i­ly increase their gen­er­a­tion out­put, while the non-spin­ning reserve is the extra gen­er­at­ing capac­i­ty that is not yet con­nect­ed to the grid, but can be brought online after a short delay.  

After about 30 min­utes of under-sup­ply, the replace­ment reserve kicks in to main­tain the abil­i­ty to react to grid inbal­ances in the short-term, or in oth­er words, to restore the oper­a­tional reserve.

The Technological Challenge: Interoperability

The dif­fi­cul­ty in pro­vid­ing such ser­vices lies in the com­plex­i­ty of gen­er­a­tion plants. Con­trol­ling the gen­er­a­tion out­put of an elec­tric facil­i­ty requires com­mu­ni­ca­tion between mul­ti-ven­dor gear and equip­ment, which speak dif­fer­ent pro­to­cols and oper­ate on sev­er­al com­mu­ni­ca­tion lay­ers. Fur­ther­more, spe­cial­ly with renew­able plants, there are often sev­er­al actors involved who must be able to con­trol the plant or access the plant data: the grid oper­a­tor, the oper­a­tion and mai­t­e­nance com­pa­ny, the investor and some­times aggre­ga­tors or ener­gy traders. For exam­ple, the TSO might want to access the plant for real-time elec­tri­cal data through the not-so-com­mon ICCP pro­to­col, while the investor wants flashy his­tor­i­cal graphs on his web brows­er. This often leads to gener­ic or com­plex and inflex­i­ble net­works, often requir­ing the use of inter­con­nect­ed or par­al­le­ly func­tion­ing plat­forms and environments.

Thanks to the unique pro­to­col suite and the advanced automa­tion capa­bil­i­ties by iGrid’s soft­ware core iGComms, iGrid T&D can pro­vide scal­able gen­er­a­tion plant mon­i­tor­ing and con­trol solu­tions that are easy to set up and  open for retro­fits and extensions.

All-in-One Communication Systems

iCon­trol SCADA sys­tem can act as plant gate­way to con­nect to the grid-con­nect­ing sub­sta­tion devices and pow­er plant equip­ment such as meters and sen­sors, pow­er plant con­troller, SCADA/HMI for pow­er plants or pow­er plant con­trol and gen­er­a­tion dis­patch con­trol cen­ter to effi­cient­ly oper­ate and pro­vide ancil­lary ser­vices with an entire port­fo­lio of plants. Thanks to our expe­ri­ence with pow­er plant SCADAs, iCon­trol pro­vides high-end func­tion­al­i­ties for the oper­a­tion and main­te­nance (O&M) of pow­er plants.

With our iGW and iRTU fam­i­ly, you can also ensure inter­op­er­abil­i­ty between all third par­ty devices and your pow­er plant con­trollers, gate­ways and RTUs. 

Generation Dispatch With On-Site Data Collection

Con­cep­tu­al schema

Our Dispatch Control Center Solution — Everything in One Platform

Our Dis­patch Con­trol cen­ter can oper­ate as a SCADA and dis­patch­ing agent to a port­fo­lio of pow­er pro­duc­tion plants. In cur­rent projects we have ener­gy traders oper­ate port­fo­lios with a diverse vari­ety of gen­er­a­tion tech­nolo­gies, such as com­bined heat and pow­er, com­bined cycle, nuclear, solar, wind and hydro. All plants are mon­i­tored and con­troled from the same plat­form with the same envi­ron­ment through­out all lev­els, from sub­sta­tion sca­da to con­trol cen­ter. With just a few clicks you can find all rel­e­vant infor­ma­tion for each facil­i­ty, such as IED sta­tus, meter­ing data, invert­er per­for­mance, elec­tri­cal data and events. The con­trol cen­ter also pro­vides event mange­ment to act on fail­ures in real time.

The dis­patch con­trol cen­ter can direct­ly com­mu­ni­cate with the main grid oper­a­tor via ICCP/TASE2. In our biggest project in Spain, the con­trol cen­ter direct­ly com­mu­ni­cates with the con­trol cen­ters from the nation­al grid oper­a­tor (REE) and the Con­trol Cen­ter for Renew­able Ener­gies (CECRE) to receive direct dis­patch com­mands for the gen­er­a­tion plants that are con­nect­ed to the sys­tem. In order to main­tain a flu­ent and effi­cient com­mu­ni­ca­tion between the ener­gy pro­duc­tion sys­tem and the reg­u­la­to­ry sys­tem, the dis­patch­ing cen­ter can also pro­vide redun­dant infra­struc­ture with hot-stand­by servers with SQL data stor­age and mul­ti­ple oper­a­tor workstations.

Dispatching & Frequency Response Services with Embedded AGC

The plants pro­vide pri­ma­ry and sec­ondary fre­quen­cy reserve response by mak­ing use of auto­mat­ic gen­er­a­tion con­trol algo­rithms devel­oped by the Uni­ver­si­ty of Comil­las, also inte­grat­ing inter­nal­ly devel­oped log­ics, which are adjust­ed accord­ing to the needs of the spe­cif­ic gen­er­a­tion plant.
The sys­tem fea­tures a spe­cial mod­ule to com­fort­ably pro­vide the TSO with expected/programmed gen­er­a­tion
out­puts and fre­quen­cy reserve pow­er ranges (24–48h in advance) while meet­ing all respec­tive require­ments. In this way you can pro­vide bids and con­nect to the ener­gy mar­ket in the eas­i­est way, from the same plat­form you can oper­ate the plant and access KPIs, graphs and sub­sta­tion data.

Fur­ther, the con­trol cen­ter also con­ti­nous­ly check the gen­er­a­tion out­put and exchanges pow­er reg­u­la­tion sig­nals with the TSO, accord­ing to the require­ments set by REE. The TSO can track elec­tri­cal data from and send direct dis­patch­ing com­mands to the plants in real-time (via ICCP/Tase.2). These com­mands are processed by the AGC and con­vert­ed by the SCADA and on-site devices, which trans­fer them ven­dor-inde­pen­dent­ly on to the gen­er­a­tion plants via IEC 60870–104, Mod­bus TCP and oth­er pro­to­cols in order to con­trol the gen­er­a­tion out­put of each site individually.

Thanks to our pow­er­ful com­mu­ni­ca­tion core, we can not only enable big pow­er plants but also aggre­ga­tors to sup­ply ancil­lary ser­vices with a fleet of small­er gen­er­a­tion plants.

All gen­er­a­tion plants includ­ed in the port­fo­lio, can be con­trolled from any­where and any­time via the iCon­trol web serv­er. The same chan­nel can be used by owners/investors, who are grant­ed an indi­vid­ual user which only allows to access the infor­ma­tion of their own plant.

World-wide Compliance and Interoperability

We are aware of the impor­tance of accu­rate­ly under­stand­ing the needs of sys­tem oper­a­tors and the func­tion­al spec­i­fi­ca­tions set up by TSOs. Thanks to our expe­ri­ences with elec­tri­cal net­works and sub­sta­tions in a vari­ety of indus­tries all around the plan­et, our prod­ucts have been pre­pared for an imm­mense range of high-demand­ing require­ments and stan­dards, guar­an­tee­ing a peace­ful approval process for any project in any coun­try. Our cer­ti­fi­ca­tions range from EMC com­pat­i­bil­i­ty and com­mu­ni­ca­tion pro­to­col stan­dards like IEC 61850 to cyber secu­ri­ty mea­sures and have been assert­ed by third par­ty cer­ti­fi­ca­tion bod­ies like DNV GL/ KEMA.

Powerful and Reliable Hardware for Communication Networks

We want to keep the oper­a­tion of your pow­er net­work as sim­ple as pos­si­ble with­out renounc­ing advanced func­tion­al­i­ties. For this rea­son, based on our in-field expe­ri­ence, we designed pow­er­ful and flex­i­ble hard­ware for the ener­gy indus­try. Our user-friend­ly hard­ware facil­i­tates smooth imple­men­ta­tions and can be eas­i­ly adjust­ed to your needs with our free & sim­ple iConf tool. 

We are aware of the broad diver­si­ty of com­po­nents a sys­tem con­struc­tor is con­front­ed with. With our solu­tions you no longer need to wor­ry about sys­tem topol­o­gy, com­mu­ni­ca­tion media, com­pat­i­bil­i­ty or net­work inef­fi­cien­cies.

We encour­age to set up open and scal­able com­mu­ni­ca­tion net­work archi­tec­tures, which will allow you to com­fort­ably react to any kind of changes in your plan­t’s net­work and replace third par­ty devices at any giv­en time.

Although our devices are already con­fig­urable and ver­sa­tile by design, we also pro­vide fur­ther prod­uct con­fig­u­ra­tions and tai­lored ser­vices upon request.

Why to Opt for a Generation Dispatch Control Center by iGrid T&D? 

Our gen­er­a­tion dis­patch con­trol cen­ter solu­tion com­bines state-of-the-art sub­sta­tion automa­tion and SCADA tech­nol­o­gy with all func­tion­al­i­ties the grid oper­a­tor requires and all involved actors need.

Thanks to our focus on advanced com­mu­ni­ca­tion net­works in ener­gy appli­ca­tions and our expe­ri­ence with gen­er­a­tion facil­i­ties, we can pro­vide a unique­ly flex­i­ble and scal­able all-in-one solu­tion that is easy to use and saves a lot of costs through­out the entire project.

Solution Benefits & Functions