Konfiguracin da Winding na Transformers mai Yawa don Kisan Kwakwalwa PV a Tsakiya

Gimba gida na tsarin kurfa na shamsi, wanda yake da muhimmanci a cikin hanyoyin amfani da zuwa shamsi, tana kawo rarrabe zuwa karamin kashi ne a kan wuraren solar. Babu iya a tabbatar da zafi, mutanen abubuwa ko matsalolin hadiza, kuma yana da kyau ga al'adun duniya. Ana sanar da suna a fannin PV da take girma, masu inganci (wurare masu ingancin kawo karfi) sun fi sani sosai. Yanzu, masu ingancin kawo karfin PV sun yi amfani da SC-series epoxy-insulated dry-type units na 10 kV/35 kV, wadanda ana samun biyu-winding da double-split. Littafin ya nuna bayanan za su duba.

1 Biyu-Winding Dry-Type Transformers

Tsari na biyu-winding dry-type transformers don PV (kamar yadda aka nufin a Figure 1, reference mai ba a bace-bace) babu kisan laifi daga cikin tsarin distribution dry-type na zaman lafiya, hanyar inganci, da yanayin kawo - farkon maida. Duk da cewa abin da ke faru shine wannan shugaban kawo karfi. A lokacin da inverter mai ban sha'a, ana samun biyu-winding unit da ya danganta da rated output da voltage na grid.

Saboda inverter operation ya iya haifar da neutral-point grounding ta transformer, da kuma harmonics suna da shi, connection group ya fi son Dy11 don bincike cewa zafi na abubuwan da suka dogara.

2 Double-Split Dry-Type Transformers

A shekarun da suka karkashin, don in hana current na short-circuit da in kusa capital costs, ana samun split transformers (da winding, tare da low-voltage, ya sa electrical disconnected branches ²) da suke so kuɗi. Don PV projects, double-split transformers suna da muhimmanci: biyu independent inverter units suna haɗa da biyu branches na double-split winding, zai iya dogara da mutum ko daɗi.Saboda harmonics na inverter, connection group ya fi son D, y11y11 ko Y, d11d11. A cikin gwamnati, suna da tsari axial-split ko radial-split.

Kamar yadda aka nufin a Figure 2 (reference mai ba a bace-bace), low-voltage winding na biyu branches na axially-distributed a kan core mafi girma. Branches babu electrical connections amma suna da magnetic coupling (darajar depends on structure ²), kuma zai iya da segmental ko wire-wound. High-voltage winding na biyu parallel branches da ya danganta da low-voltage ones, da specs da take danganta da total capacity da ya danganta da transformer.

2.1 Axial Double-Split Dry-Type Transformers

Da tsari symmetrical da leakage flux uniform, yana yi aiki a through/half-through operation. Impedance mai yawa da biyu branches na axially-split ya hana short-circuit currents, baki daya branch zai iya dogara idan daya fail.

Amma, high-voltage winding (biyu parallel windings) ya duba turns kafin ya haka cross-section da conductor vs conventional. Design 35kV D-connected ya haƙa winding production issues (turn control, low efficiency), wanda yake haƙar da safety/reliability.

Duk da haka, upper/lower low-voltage windings (arranged vertically) na ~20K temperature difference (upper hotter saboda air convection). Saboda haka, design/manufacturing yana buƙata checks mai yawa da temperature rise da insulation selection daidai.

2.2 Radial Double-Split Dry-Type Transformers

Common radial double-split dry-type transformers (structural layout in Fig. 3) na biyu branches na low-voltage winding na radially-distributed (usually wire-wound, due to structural specificity) da single integral high-voltage winding.

High-voltage winding, da normally-selected turns da conductor cross-section, yana da winding process/efficiency mai yawa da axial double-split types. Symmetry mai yawa yana bincika ampere-turn balance a through/half-through operation, plus uniform low-voltage winding temperature rise.

Amma, radially-split low-voltage windings na small division impedance da large coupling capacitance, wanda yake ha inter-winding interference. Wannan yana ha power quality da reliability na inverter components, wanda yake buƙatar adjustments to the inverter-side control loop and system.

2.3 Special Double-Split Dry-Type Transformers

Fig.4 tana nuna design mai hybrid wanda yake haɗa da axial (segmental/wire-wound low-voltage) da radial (single high-voltage) splits. Wannan hybrid tana haɗe radial low-voltage da axial high-voltage issues, wanda yake hana costs da improving manufacturing efficiency.

Amma, half-through operation (saboda environmental factors ko inverter faults) yana ha ampere-turn imbalance mai yawa, wanda yake ha end-winding leakage flux da overheating. Wannan design tana da risk mai yawa.

3 Conclusion

Grid-connected PV transformers primarily use two-winding (step-up, D, y11) or double-split configurations. Key recommendations for double-split designs:

• Maintain sufficient low-voltage division impedance for power quality.

• Account for axial split temperature differentials in insulation selection.

• Use Y, d11d11 for 35kV applications.

• Avoid special hybrid designs due to half-through operation risks.