Matsayin Yadda Ƙarƙashin MVDC Shaida? Faɗila, Dangantaka da Tashaya na Gaba

Tattalin tsari na kwayoyin karamin kashi (MVDC) yana cikin tashar karamin kashi, wanda ake fadada don dole kungiyoyi na cikin AC na gaba-gaban a tushen kayan aiki. Ta karama kashi a kan DC da kwayoyin karamin kashi daga 1.5 kV zuwa 50 kV, ta haɗa muhimmin abubuwa na karamin kashi a kwayoyin takwas da dalilai na karamin kashi a kwayoyin ƙasa. A lokacin da take daɗe wannan tashar karamin kashi na kwayoyin takwas da kuma tushen karamin kashi masu zamani, MVDC yana faruwa a matsayin bincike mafi muhimmanci don kawo hankali ga jamiyar karamin kashi.

Sisteminsu mai ban sha shi suna ƙarin abubuwa: birnin kofin karamin kashi, kabelon DC, kofin kudurkar, da manufar kontrol/ingantaccen. Birnin kofin karamin kashi suka amfani da teknologiyyar modular multilevel converter (MMC), wanda ke kofin karamin kashi da kyau a cikin submodules da suka damar fitowar kashi da kuma kofin kashi don inganta kwallon kofin kashi. Kabelon DC suka amfani da kwalbar cross-linked polyethylene da kuma kofin kashi mai kuliya, wanda ke ɗaukan kofin kashi a kabelon. Kofin kudurkar DC mai al'adu ke kudurkar kofin kashi a nanodawo, wanda ke sautin sistem. Manufar kontrol da ingantaccen, wanda ke gina a kan platfoamai na digital simulation na zaman lafiya, ke iya bayyana kofin kashi a nanodawo da kuma samun kofin kashi a nanodawo.

A cikin aiki, MVDC yana nuna fa'idodi masu ƙarin abubuwa. A cikin kofin kashi na motoci, kofin kashi na 1.5 kV DC ke kofin kashi da zama 40% da kuma kofin kashi da zama 30% musamman zuwa kofin kashi na AC. Data centers da suka amfani da kofin kashi na 10 kV DC ke samun fa'idoda da 15% da kuma kofin kashi da zama 8%. A cikin kofin kashi na ƙasar kaya, amfani da ±30 kV DC collection systems ke kofin kashi da zama 20% zuwa kofin kashi na AC da kuma kofin kashi da zama ƙananan kofin kashi. A cikin kofin kashi na ƙasar kaya, MVDC traction systems ke kofin kashi da zama 50% da kuma kofin kashi da zama 92%.

Teknologiyyarsu yana ba da fa'idodi uku: kofin kashi da zama 10-15% zuwa kofin kashi na AC a kwayoyin kashi, yadda ya fi yawa a cikin integration da karamin kashi; babu buƙata don synchronization da kashi, wanda ke ɗaukan interconnection bayan grids; da kuma response da kofin kashi a nanodawo, wanda ke ba da ƙarfin adana a cikin karamin kashi. Amma, kungiyoyi suna da su, ciki har da cost of equipment da kuma standardization da ba ake samu. Kofin kashi da kofin kashi da zama 3-5 times more than AC equivalents, da kuma unified international certification standards da ba ake samu.

Standardization tana ci gaba. IEC tana fitowa IEC 62897-2020 don kabelon MVDC, China's CEC tana fitowa Q/GDW 12133-2021 don specifications da converters, da kuma Horizon 2020-funded MVDC grid demonstration project tana kammala validation testing ta 18 kV/20 MW system. Domestic equipment manufacturing tana samu breakthroughts: Chinese manufacturers tana mass-produce 2.5 kV/500 A IGBT modules da dynamic voltage balancing error within ±1.5%.

Trendoin da za a faru sun hada da: miniaturization of devices—SiC-based compact converters can reduce volume by 40%; system intelligence—digital twin technology improves equipment lifespan prediction accuracy to over 95%; and application expansion—space-based solar power microwave wireless transmission systems are beginning ground reception tests using 55 kV DC architectures. As power electronics costs continue to fall, MVDC is expected to become economically superior to traditional AC solutions in distribution grid upgrades by 2030.

Technology deployment requires cross-sector collaboration. Power design institutes are developing 3D digital design platforms for converter station layout optimization and EMI simulation. University research teams are advancing novel topologies, with dual-active-bridge converters achieving 98.7% efficiency. Utility pilot projects show that 20 kV DC microgrids in industrial parks can boost renewable penetration to over 85%. These initiatives provide valuable data for technological iteration.

Within new power systems, MVDC plays a pivotal role, bridging UHVDC backbone networks and low-voltage distributed sources to form flexible, multi-voltage DC networks. Case studies show that intelligent substations with 10 kV DC busbars can increase photovoltaic absorption by 25% and sustain critical loads for over 4 hours during main grid outages. As digital grid development progresses, MVDC systems are increasingly integrating with edge computing and blockchain to form self-regulating energy internet nodes.

Practical engineering requires attention to detail: cable installation must strictly control bend radius—minimum 25 times the cable diameter for 35 kV DC cables. Electromagnetic compatibility must meet CISPR 22 Class B standards, with converter room shielding effectiveness exceeding 60 dB. Operation and maintenance should include infrared thermography every 3 months and online partial discharge monitoring with thresholds below 20 pC, ensuring safe and stable operation.

From an energy transition perspective, MVDC is a key enabler for zero-carbon grids. It allows direct DC grid connection for wind and solar, eliminating 6–8% energy loss from AC inversion. In hydrogen production, 50 MW electrolyzers using 10 kV DC power achieve 12 percentage points higher efficiency than AC-powered systems. Cross-industry applications are expanding: maglev trains using 3 kV DC power reduce traction energy consumption by 18%. These innovations are reshaping energy utilization.

The industry faces talent shortages. There is a significant gap in professionals skilled in both power electronics and grid operations. Chinese universities have introduced specialized MVDC courses, and the National Occupational Qualification Catalog now includes a DC Distribution Engineer certification. Corporate training centers use full-scale simulation platforms to train personnel in emergency response under various fault scenarios. This talent development model is shortening technology transfer cycles and accelerating innovation deployment.