35kV SFZ22 Series Oil-immersed Transformers: Technical Overview The 35kV SFZ22 series oil-immersed transformer is a robust and efficient power distribution device designed for medium-voltage applications. It features a rated voltage of 35kV, making it suitable for industrial plants, substations, and utility networks requiring reliable energy transformation with minimal losses. Key Features 1. Core and Winding Design - Constructed with high-grade grain-oriented silicon steel laminations to reduce core losses and improve magnetic efficiency. - Copper or aluminum windings (depending on specifications) ensure low resistance and high short-circuit withstand capability. - Axial and radial cooling ducts optimize heat dissipation, enhancing thermal stability. 2. On-Load Tap Changer (OLTC) - Equipped with an SFZ22-type OLTC (typically ±8×1.25% or ±4×2.5% adjustment range) to regulate output voltage without interrupting power supply. - Ensures stable voltage under fluctuating load conditions, critical for grid stability. 3. Cooling System - Utilizes mineral oil for insulation and cooling, with ONAN (Oil Natural Air Natural) or ONAF (Oil Natural Air Forced) cooling modes. - Corrugated tank or radiator panels maximize surface area for efficient heat exchange. 4. Safety and Protection - Buchholz relay detects internal faults (e.g., gas accumulation or oil flow anomalies) and triggers alarms/trips. - Pressure relief device prevents tank rupture during extreme overpressure. - Oil level indicator and temperature monitor for real-time condition assessment. 5. Efficiency and Environmental Compliance - Meets IEC 60076 and IEEE C57.12.00 standards, with low no-load and load losses (e.g., ≤10kW no-load loss at 3150kVA). - Sealed construction minimizes oil leakage risks and extends maintenance intervals. Applications - Utility substations (35/10kV or 35/0.4kV step-down). - Renewable energy integration (wind/solar farms). - Mining and heavy industries with variable loads. Advantages - High reliability: Designed for 30+ years of service with proper maintenance. - Adaptability: Customizable tap ranges, winding materials, and cooling options. - Low lifecycle cost: Energy-efficient design reduces operational expenses. In summary, the SFZ22 series combines advanced engineering with practical durability, making it a versatile solution for modern power systems. Its balance of performance, safety, and efficiency aligns with global trends toward smarter, greener grid infrastructure. (Word count: 500)