Substation Step Voltage Regulators To'liq Yechimlari: Ishlash Printsiplardan Kelajak Yo'nalishlarigacha

1. Adimli regulyatorlar ishlash printsipi va texnologik rivojlanishi

Adimli napon regulyatori (SVR) modern substantsiyalarda naponni to'g'ri qilish uchun asosiy qurilma bo'lib, tapo'zgartirish mekanizmlari orqali aniq napon stabilizatsiyasini ta'minlaydi. Uning asosiy printsipi transformator nisbatini o'zgartirishga asoslangan: napon o'zgarish aniqlanganda, elektr motori yordamida tappalar o'zgartirilib, spiral tebranishlari nisbati o'zgartiriladi, shuning bilan chiqaruvchi napon o'zgaradi. Tipikal SVR-lar ±10% napon nazorati bilan 0.625% yoki 1.25% adimlar bilan naponni o'zgartirish imkoniyatini ta'minlaydi, bu ANSI C84.1 standartiga mos keladi.

1.1 Adimli nazorat mekanizmi

• Tappalar o'zgartirish tizimi: Elektr motori bilan ishlov berilgan mexanik tappalar va solid-state elektron tappalar bilan birlashtirilgan. "Make-before-break" printsipidan foydalanib, o'tkaziladigan arusni cheklash uchun o'tish omillari ishlatiladi, bu esa bekor qilinmasdan energiya ta'minlashini ta'minlaydi. Tappalar 15–30 ms ichida o'zgartiriladi, bu nisbatan sezgir qurilmalar uchun napon pasayishini oldini oladi.
• Mikroprotsessorli boshqaruv moduli: 32-bit RISC protsessorlar bilan jihozlangan, real vaqt rejimida napon o'lchovlari (≥100 namunalar/sekund) amalga oshiriladi. DSP asosidagi FFT tahlili orqali asosiy va garmonik komponentlarni ajratish, ±0.5% aniqlikda o'lchov imkoniyatini ta'minlaydi.

1.2 Modern digital boshqaruv texnologiyalari
Ko'plab funksiyalarga ega boshqaruv modullari murakkab holatlarni optimallashtirish imkoniyatini beradi:

• Avtomatik napon kamaytirish (VFR): Tizim yuklanishida chiqaruvchi napon kamaytiriladi, bu esa zararlar 4–8% miqdorida pasayadi. Formula: Eff. VSET = VSET × (1 - %R), bu yerda %R (tipikal 2–8%) kamaytirish nisbatini belgilaydi. Misol uchun, 122V tizimda 4.9% kamaytirish 116V chiqaruvchi naponni beradi.
• Nopon cheklash: Ishlash chegaralari (masalan, ±5% Un) belgilanadi. Nopon buzilishlari paytida avtomatik ravishda kirish mumkin, bu yerda lokal yoki masofaviy operatorlar yoki SCADA tizimlariga mos keladi.
• Xato davom etish: Xato paytlarida (masalan, napon 70% Un ga pasayadi) asosiy nazorat saqlanadi. EEPROM xotirasi kritik parametrlarni energiya buzilishidan keyin ≥72 soatga saqlaydi.

2. Substantsiya tizim integratsiya yechimlari

2.1 Transformator tappalarini boshqarish va parallel kompensatsiya
Nopon nazorati bir nechta qurilmalar bilan koordinatsiya qilinishi kerak:

• Yuk ostida tappa o'zgaruvchi (OLTC): Asosiy nazorat qurilmasi, ±10% oralig'ida ishlaydi. Modern OLTC-lar elektron pozitsion sensordan foydalanadi (±0.5% aniqlikda) va real vaqt ma'lumotlarini SCADA-ga yuboradi.
• Kondensor banklari: Reaktiv quvvat talabiga qarab avtomatik ravishda ulanadi. Tipikal konfiguratsiyalar: 4–8 guruh, transformator reytingining 5–15% (masalan, 33kV tizimlarda 2–6 Mvar). Boshqaruv strategiyalari napon o'zgarishlarini va kuch faktorini (maqsad: 0.95–1.0) barqaror tutish kerak, bu esa o'ngirmaslikni oldini oladi.

2.2 Chiziqli pasayish kompensatsiya texnologiyalari
Uzoq masofadagi uzumlarni tashkil etish uchun tarmoqda nazorat strategiyalari ishlatiladi:

• Seriya kompensatsiyasi: 10–33kV aylanma uzumlarda seriya kondensorlari joylashtiriladi, bu 40–70% line reactance ni kompensatsiya qiladi. Misol uchun, 15 km o'rtach joyda 2000μF kondensor o'q naponini 4–8% ga oshiradi, bu yerda MOV surge arresters himoya qiladi.
• Chiziqli napon regulyatorlari (SVR-lar): Substantsiyadan 5–8 km masofada joylashtiriladi. Kapasiteti: 500–1500 kVA, oraligi ±10%. Feeder Terminal Units (FTU) bilan integratsiya qilinadi, bu yerda mahalliy avtomatika, aloqa bog'liqlikni kamaytiradi.

2.3 Qurilmalar konfiguratsiyasi

3. Advanced Control Strategies

3.1 Traditional Nine-Zone Control & Improvements
The voltage-reactive power plane is divided into 9 zones to trigger predefined actions:

• Zone Logic: Boundaries set by voltage limits (e.g., ±3% Un) and reactive limits (e.g., ±10% Qn). Example: Zone 1 (low voltage) triggers voltage increase.
• Limitations: Boundary oscillations cause frequent device actions (e.g., capacitor switching in Zone 5), and fail to handle multi-constraint coupling (e.g., voltage violation + reactive deficiency).

3.2 Fuzzy Control & Dynamic Zoning
Modern systems adopt fuzzy logic to overcome limitations:

• Fuzzification: Defines voltage deviation (ΔU) and reactive deviation (ΔQ) as fuzzy variables (e.g., Negative Large to Positive Large), with trapezoidal membership functions.
• Rule Base: 81 fuzzy rules enable nonlinear mapping, e.g.:
• IF ΔU is Negative Large AND ΔQ is Zero THEN Raise Voltage.
• Dynamic Adjustment: Expands voltage dead zones during heavy loads (±1.5%→±3%), reducing device actions by 40–60%.

3.3 Multi-Objective Optimization
For distributed energy integration scenarios:

• Objective Function:
  Min[Ploss + λ1·(Uref - Umeas)² + λ2·(Qbalance) + λ3·(Tap_change)]
  (λ: weighting coefficients; Tap_change: tap operation cost)
• Constraints:
1. Voltage safety: Umin ≤ Ui ≤ Umax
2. Device capacity: |Qc| ≤ Qcmax
3. Daily tap operations: ∑|Tap_change| ≤ 8
• Algorithm: Improved PSO optimization with 50 particles converges in <3s, meeting real-time requirements.

4. Communication & Automation Support Systems

4.1 IEC 61850 Communication Architecture

• GOOSE Messaging: Supports inter-station commands with <10ms delay. Enables coordinated voltage control (e.g., sub-stations respond within 100ms to main-station commands).
• Information Modeling: Defines logical nodes (e.g., ATCC for tap control, CPOW for capacitors), each with 30+ data objects (e.g., TapPos, VoltMag) for plug-and-play integration.

4.2 SCADA System Integration

• Data Acquisition: RTUs sample critical data (voltage, current, tap position) every 2 seconds, prioritizing voltage data transmission.
• Control Functions:
1. Remote parameter adjustment (e.g., VSET, %R).
2. Seamless auto/manual mode switching.
3. Automatic operation lock during device faults.
• Visualization: Dynamic single-line diagrams (voltage violations highlighted in red), trend curves, and audible alarms.

4.3 Key Communication Protocols

5. Performance Optimization & Validation

5.1 Voltage Optimization (VO) Protocol Implementation
U.S. Energy Association’s three-tier approach:

1. Fixed Voltage Reduction (VFR): Full-time 2–3% reduction (e.g., 122V→119V). Suitable for stable loads. Annual savings: 1.5–2.5%, but risks motor startup issues.
2. Line Drop Compensation (LDC): Dynamically adjusts voltage based on load current.
3. Automatic Voltage Feedback (AVFC): Closed-loop control using 3–5 remote sensors/feeder. PID algorithm with 30s cycles.

5.2 Performance Quantification

• Data Collection: 0.2S-class power analyzers record voltage, THD, and power parameters (1s intervals, 7-day duration).
• Energy Savings Calculation: Regression analysis excludes temperature effects.
• Key Metrics:
• Voltage compliance rate: >99.5%
• Daily device actions: <4
• Line loss reduction: 3–8%
• Capacitor switching lifespan: >100,000 cycles.

5.3 Optimization Technique Comparison