Panulong ed Balon Koneksion na Enerhiya

 

Say balon panagpawala na enerhiya, ya irerepresenta na dagem tan solar power, et mangipapatnag na baleg ya pananguman tan ag-inkaseguro na output na enerhiya. Parehon direktan naapektoan na lokal iran kondisyon na panaon so kuryente ya nanlapud dagem tan agew, ya mainomay ya ontagey o onkulang so kuryente, ya mangiter na angat ed frequency na koneksyon na kuryente.

Lapud saray pananguman na kuryente tan saray medyo komplikadon katangian na grid impedance, diad normal iran kondisyon na baleg-scale centralized grid connection odino random ya output na kuryente, posiblin nagawa so power oscillations, ya pansengegan na saray isyu ed estabilidad na sistema na kuryente. Saya so mangaapekta ed karga tan say performance na saray implanon balon sistema na produksyon na enerhiya ed malaknab a lugar, a mankaukolan na magenap a reserba a kapasidad ed sistema pian napaliisan so pakaapekto ed abilidad a mangitipon na balon lapuan na enerhiya, a makanakana pian nadampot so parehon inkaepektibo ed panagplano tan ekonomya.

Say pankasakey na panagtipon na enerhiya tan balon lapuan na enerhiya et manunan akasentro ed taloran aspekto: Unona, diad pangibulos na grid-level loads ed antikey a panaon, saya so mamasarag na 10-minute-level power regulation na power grid, ya mamalemew ed antikey a panaon ya pananguman-uman tan sigpot a pakausar ed saray wala lan kapasidad na grid ed balon lapuan na enerhiya. Kumadwa, diad panggawa na saray plano ed minuto-level ya mangilaktip na balon forecast na output na enerhiya, tan base ed antikey a panaon ya forecast na power generation ed antikey a panaon, epektibon mangilaktip na balon lapuan na enerhiya ed ultra-antikey a panaon ya power forecast. Saya so mamaaligwas ed makatunongan ya operasyon tan panag-iskedyul na nanduruman generating units ed loob na grid, mamapaabeba ed pankaukolan parad maples a frequency regulation resources, mamaaligwas ed inkasusto tan inkastabilida na saray forecast na grid, tan mamaaligwas ed minuto-level real-time fluctuations ed balon lapuan na enerhiya, ya mamalemew ed epekto ed normal ya operasyon na saray conventional generating units.

Peak Shaving tan Valley Filling

No ikompara ed kaslakan ya panagpawala na kuryente, say panagpawala na renewable energy et walaan na abeban uusaren iran kagawaan o yunit to. No alaen so "Three Norths" ya rehyon na bansa mi bilang alimbawa, unong ed estadistika na wind resource, say posibilidad ya say dagup ya output na sakey a wind farm et onlampas ed 60% na dagup ya kapasidad to et kaslakan ya kulang ed 5%. Pian napaaligwas so pangusar na linya, say panagplano na kapasidad na linya et kaslakan ya mankaliktan na 95% na pankaukolan ed transmisyon na kuryente na dagem odino 60% na dagup ya akapueston kapasidad na saray wind farm. Mas grabe ni so situasyon parad saray photovoltaics. Kanian, walay pigaran porsiento na enerhiya na dagem ya nabawasan lapud kulang so kapasidad na transmisyon, tan say enerhiya na agew et nabawasan lapud ag-inkayadyari na karga (anti-peak-shaving characteristics).

Say renewable energy production, ya walaan na medyo andukey a panaon ya manguuman-uman ed kada oras ed interon agew, tan say isabi na sankatageyan a pankaukolan na kuryente ed labi (kaslakan et 7-10 PM), so mamarakep ed saray kakaukolanen na sistema ya ontagey tan onleleksab so kapasidad to. Say enerhiya na dagem, diad biek a dapag, et mabetbet ya onsasabi ed sigpot a pakayari to nen manga pegley-labi, no say karga et walad sankaabebaan a punto na sanagew. Kanian, pian naekal so agpakaseguroan ed pangipropesiya na renewable energy generation, say power grid tan saray conventional generating units et nepeg ya walaan na baleg iran peligro ya misiglaotan ed deep peak shaving.

Say peak shaving tan valley filling et manguusar na time-shifting characteristics na energy storage pian napalaknab so line transmission capacity, nabawasan so pankaukolan ya mipara ed load trends, tan nabawasan so pankaukolan parad ondarakel tan onkupas ya kapasidad manlapud saray conventional generating units.

Diad pantipon ed inagew-agew ya load curve P_l ed renewable energy generation output curve P_{NE}, naala tayo so pinal ya system equivalent load curve ∑P_i, salanti, ∑P_i=P_l - P_{NE}. Balet, no ikonsidera so output regulation range na saray conventional power plants tan peak-shaving power plants, tan say sankatageyan ya power P_L ya nayarin ipawit o naala na regional interconnection line ed external grid, say sankatageyan ya epektibon power P_{max} na saray grid-connected units et:

P_{max}=μ(P_f + P_b + P_L) (3-3)

Iner:

say pasen labat ya naromog mo ed paway na abung

 

 

• P_f-Maximum output power na peak-shaving units;
• P_b-Minimum ya output na saray yunit ya ag makapibiang ed peak shaving;
• μ-Grid transmission tan operating efficiency.

Diad pormula, say C et mangirerepresenta ed output power regulation coefficient na peak-shaving unit. Saray relasyon na pakayari et nanengneng ed pigura.

Say sankaabebaan ya epektibon pakayari P_{min} na grid- ya akakonekta iran yunit et:

Legan na sankaabebaan a panaon na karga t1–t2, say kapasidad na downward regulation ya reserba na saray kombensional a peak-shaving units et say sankatageyan a renewable energy power P'_{NE} ya nayarin awaten na grid legan na sayan panaon, salanti, P'{NE}=P{max} -= P{max} -{}{}}{5-min}{}{5-} a ditan et say sankaabebaan ya inagew-agew output (no anggapoy panagtipon na enerhiya, say pakawalaan na renewable energy legan na t1–t2 et nagawa labat diad panamegley na wind/solar curtailment).

Nanengneng ya no anggapoy panag-imbantak na enerhiya, say renewable energy output legan na t₁–t₂ et limitado labat; balet, diad panagtipon na enerhiya, say panag-charge legan na t1–t2 tan say panag-discharge legan na t3–t4 et mangiyalis ed epektibon katumbas na kurba na karga ∑P_i ed loob na P_{min} tan P_{max}, ya napaliisan so limitasyon na renewable energy output tan say wind/solar curtailment, ya napaaligwas so renewable energy absorption capacity, tan nabawasan so kapasidad na grip say pankaukolan parad reserba ya kapasidad, tan say pamaaligwas ed inkalapagan ya inkaepektibo na sistema. Say pakayari P_{BESS} na BESS (Battery Energy Storage System) et:
P_{BESS}=max( P_{min} - ∑P_{min}, ∑P_{max} - ∑P_{max} ) (3-6)
Say enerhiya E_{BESS} na BESS et:

E_{BESS}=max{ μ_c ∫{t₁}^{t₂} (P{min} - ∑P_i) dt , 1/μ_d ∫{t₃}^{t₄} (∑P_i - P{x)} dt (})

Iner:

 

• μ_c -- Say inkaepektibo na panagkarga na sistema na panagtipon na enerhiya;
• μ_d -- Say inkaepektibo na panag-discharge na sistema na panagtipon na enerhiya.

Say kaaruman ya panagsukimat ed mas malaknab a kabaliksan et mangipapanengneng ya parad saray load peak tan valley ya mabetbet ya manbayag, say pangi-configure na energy storage system ya walay kapasidad to et epektibon mamawas ed peak-valley ya pandumaan, a singa nanengneng ed pigura.

Say inyaligwas na pandumaan na load peak-valley et:

• No iner so P_imaxsay sankatageyan ya iilaloan ya karga;
• P_imaxso sankaabebaan ya iilaloan ya karga.

Say paraan na pangiyuksoy na sistema na panagtipon na enerhiya et mipara ed samay akaunan paraan tan ag la naulit.

Paaligwasen so inkasusto na panaghula

Unong ed NBT32011-2013 "Technical Requirements for Power Prediction System of Photovoltaic Power Station", say root mean square error na short-term prediction legan na panaon na panagpawala na kuryente na sakey ya photovoltaic power station (aliwan kaiba iray panaon ya limitado so output) et nepeg ya kulang ed 015 ed sakey bulan, tan nepeg ya mas baleg nen say rate kada bulan. 80%; say root mean square error na komapat ya oras na ultra-short-term prediction et nepeg ya abeba nen 0.1, tan say monthly pass rate et nepeg ya mas atagey nen 85%.

Unong ed "Interim Measures for the Administration of Wind Farm Power Forecasting and Early Warning", say sankatageyan ya error na inagew-agew ya forecast curve na wind farm et ag onlampas ed 25%, say real-time forecast error et ag onlampas ed 15%, tan say root mean square error na forecast parad interon agew et nepeg ya ag onlampas ed 25% 20%.

 

Parehon short-term tan ultra-short-forecast so mangiiter na forecast data ed 15-minuton agwat. Kanian, say output na balon lapuan na enerhiya et nayarin na-segment tan nakontrol ed 15-minuton interval, ya walay 96 ya control segments ed interon agew. Say naabuloyan ya control error bandwidth ΔP et niletneg base ed sankatageyan ya naabuloyan ya error ed saray matukoy ya teknikal ya detalye na panag-forecast. Unong ed nanengneng ed Figure 3-8, say P(1) tan Pe(2) so naisip ya power values ​​parad unaan tan komaduan 15-minuton interval, unong ed inkauksoy da, bangta say AP et say naabuloyan ya error bandwidth, ya aka-set ed 15% na in-install ya kapasidad na balon energy generation.

Say antikey a panaon ya pananguman na panagpaalagey na balon enerhiya

Say antikey a panaon na pananguman na balon enerhiya ya makapawala na kuryente et nepeg met ya makasumpal ed saray kakaukolanen na estabilidad na sistema na kuryente. Say kaplesan ya limitasyon na power grid parad aktibon power variation na balon energy grid- ya akakonekta ed power generation et nanengneng ed table ed leksab.

Diad saray aplikasyon na renewable energy smoothing, say BESS (Power Equipped Element System) et uusaren pian isimpen tan ibulos so renewable energy generation, ya mamatunda ed saray minuton-level na power fluctuations ed renewable energy grid-connected system. Saya so mamaseguro ya say pankakasakey na output P fluctuation na energy storage PBEss (Power Element System) tan say renewable energy Pv (Power V) et makasumpal ed saray abitlan teknikal a kakaukolanen, ya say control time interval et maslak ya 1 minuto. Balet, aliwan singa saray algorithm ya mamaaligwas ed inkasusto na panaghula, sayan paraan et manunan akasentro ed saray pananguman na pakayari na renewable energy output. Kanian, diad pampili na espisipikon rated power na BESS, say data sample source parad statistical analysis tan probability analysis et say minute-level tan 10-minute-level ya active power changes na renewable energy output.

Say desinyo na pakayari tan kapasidad na BESS et nayarin ibase ni ed saray estadistika na posibilidad na apalabas iran pananguman na pakayari tan saray natipon ya pananguman ed konsumo na pakayari, ya say getma et nasumpal iray pankaukolan ed panag-smoothing ed 80% anggad 90% na kaso. Agla iya naulit dia. Pian naseguro ya say power fluctuation range et makaabot ed saray kakaukolanen ed tagey, duaran manunan BESS power control algorithms so inusar:

• Say sakey et say point-by-point limiting method;
• Say sananey et say low-pass ya paraan na panagsalat.

Point-by-point limit method

 

No alaen so pigura bilang alimbawa, say pigura so mangipapanengneng na baleg a panangikompara ed baetan na balon enerhiya ya ompaway ya P_ne(j) diad oras j tan say nankakasakey ya output P(J-n) ed apalabas ya 10 minutos. Nanengneng ya diad panaon (j-3), salanti, say pananguman ed baetan na P(j-3) tan P_ne(j) so sankabalgan, tan onlampas ed sankatageyan ya 10 minuto. Ipapanengneng na panangikompara ya △P₁₀.

Kanian, pian naabot so 10-minuton limitasyon na power fluctuation, say output range na BESS (positibo parad panag-charge, negatibo parad panag-discharge) et:

Low-pass ya paraan na panagsalat

 

Base ed prinsipyo na panagsalat ed panagproseso na signal, singa nanengneng ed pigura, say low-pass filter et mamapaabig ed output signal diad pangidagdag o pangibawas ed amplitude na input signal. Ontan met, say pakagamor na BESS et makadampot met na pan-smooth na fluctuation na output power na balon energy power station diad panamegley na charging tan discharging control to, pian nasumpal iray makanakanan teknikal a kakaukolanen.

Say iilaloan ya balor na dagup na grid- ya akakonekta ya pakayari ∑P\\sum P∑P et niiter na:

I-discretize so data, ya say t et say control period, tan mangala tayoy 1 minuto:

∑P(j)=(τ / (τ + t)) * ∑P(j-1) + (t / (τ + t)) * P_ne(j)

Niiter so ∑P(j)=P_ne(j) - P_bess(j)

P_bess(j)=(τ / (τ + t)) * (P_ne(j) - ∑P(j-1))

P_bess(j)=(τ / (τ + t)) * (∑P(j) - ∑P(j-1))

Unong ed saray teknikal ya kakaukolanen ed grid-connected power fluctuation, say minuto-level ya fluctuation range ya ∑P(j) et nepeg ya makapenek ed:

|∑P(j) - ∑P(j-1)| Mas abeba o mipara ed min(ΔP_i, 0.1 P_0)

Say pangisaliwan ed pormula na kalkulasyon parad P_sankaabigan(j) naala tayo: