Dynamic Reactive Power Compensation Solution for Electric Furnace Transformers

Dynamic Reactive Power Compensation Solution for Electric Furnace Transformers​

Electric furnaces (particularly arc furnaces and submerged arc furnaces) exhibit significant ​shock load characteristics​ during smelting processes, causing ​severe power factor fluctuations (typically between 0.6 and 0.8)​. This not only leads to grid voltage fluctuations, flicker, and harmonic pollution but also increases line losses and reduces grid power supply efficiency.

To address this challenge, this solution employs ​high-performance dynamic reactive power compensation devices (such as SVC/TSC or SVG)​, integrated with coordinated control of the electric furnace transformer:

1. ​Real-time Monitoring & Dynamic Response: High-speed sensors continuously capture system parameters (power factor, voltage, current, etc.). Using advanced control algorithms (e.g., instantaneous reactive power theory), data analysis is completed within ​10~20ms, triggering compensation commands.
2. ​Precise Reactive Power Regulation: Automatic switching of capacitor banks/reactors (TSC/TCR mode) or rapid IGBT-based reactive power output adjustment (SVG mode) responds to load changes. This dynamically stabilizes the power factor ​above 0.92​ and suppresses voltage flicker to within ​IEEE 519 standard limits.
3. ​Synergistic Efficiency Optimization: The compensation device and transformer form a closed-loop control system, reducing transformer copper and iron losses, minimizing grid reactive power flow transmission, and collectively lowering ​line losses by 6%~15%​.

​Value Realization:

• Enhanced Grid Stability: Reduces voltage fluctuations, preventing tripping of surrounding equipment during furnace operation.
• Compliance with Power Quality Standards: Meets stringent industrial requirements (THD ≤ 5%, flicker Pst ≤ 1.0).
• ​Reduced Operating Costs: Avoids utility power factor adjustment penalties and extends transformer lifespan.
• ​Compatible Expansion Capability: Supports integration with Active Power Filters (APF) for combined "Reactive Power + Harmonic" management.

​Typical Application Scenarios:
► Steelmaking Arc Furnaces ► Ferroalloy Submerged Arc Furnaces ► Si-Ca-Ba Smelting Furnaces ► Carbon Electrode Baking Furnaces

​Solution Advantage Description:

1. ​Core Technology​
   Utilizes fully digital control chips (e.g., DSP+FPGA architecture) for millisecond-level response, far exceeding the compensation speed (seconds) of traditional contactor switching. This accommodates the abrupt load changes characteristic of electric furnaces.
2. ​Cost Optimization​
   Designed for medium-voltage grids (6~35kV). Δ/Y-connected multi-stage capacitor bank configurations reduce per-unit capacity costs. Coordinated with transformer tap changers to minimize compensation device capacity requirements, lowering investment costs by over ​30%​.
3. ​Reliability Assurance​
   Features built-in harmonic protection algorithms (auto-avoidance of 5th, 7th, 11th harmonic resonance points), temperature monitoring, and rapid arc-flash bypass protection. Achieves an equipment ​MTBF (Mean Time Between Failures) of 100,000 hours.