Eastern European power system temperature measurement optical cable model

Optical fiber-based distributed temperature sensing (DTS) and Raman-effect systems are widely used in Eastern European power grids for real-time cable temperature monitoring.

Overview of Optical Cable Temperature Monitoring

Modern power systems in Eastern Europe increasingly rely on optical fiber sensors embedded in or alongside power cables to monitor temperature along long distances. These systems provide real-time, spatially distributed measurements, enabling operators to detect hotspots, prevent thermal overload, and optimize power flow without installing multiple discrete sensors .

Key Technologies

1. Raman-based DTS Systems
   • Use the Raman scattering effect to measure temperature along the optical fiber.
   • The fiber acts as a continuous temperature sensor, resistant to electromagnetic interference and non-conductive, making it ideal for high-voltage environments .
   • Systems include a laser source, backscatter detection, and software to calculate temperature profiles along the cable.
2. Distributed Acoustic Sensing (DAS)
   • Primarily used for submarine and long-range interconnectors.
   • DAS monitors vibrations and acoustic signals along the fiber, which can be correlated with thermal and mechanical stress in the cable .
   • Often combined with range extenders to cover distances beyond 100 km, ensuring full monitoring of critical infrastructure.
3. PMU-based Cable Temperature Estimation
   • Uses phasor measurement unit (PMU) data to estimate cable temperature indirectly by calculating resistance changes in 3-phase cable segments.
   • Eliminates the need for additional sensors along the cable and can achieve accuracy within ±5°C .
   • Integrates with thermoelectric equivalent (TEE) models for dynamic thermal state prediction.

System Components and Models

• Optical Fiber: Specialized low-loss fibers are used to maintain signal quality over long distances, particularly in submarine or interconnector applications .
• Temperature Measurement Device: Sends laser pulses and captures backscattered signals to compute temperature along the fiber .
• Visualization and Analysis Software: Provides real-time monitoring, hotspot detection, and historical data analysis for grid planning and operational decisions .
• RTTR (Real-Time Thermal Rating) Calculation: Software models the cable's thermal behavior under varying load conditions to optimize ampacity and prevent overheating .

Applications in Eastern Europe

• Submarine Cables: High-voltage optic–electric composite cables (110 kV and above) transmit both power and communication signals, with embedded optical fibers for temperature monitoring .
• Land Interconnectors: European TSOs deploy DAS/DTS systems to monitor 150 km or more of cable, ensuring uninterrupted power transmission and rapid fault detection .
• Dynamic Line Rating: PMU-based and optical fiber systems allow operators to adjust power flow in real time based on actual cable temperature, improving grid efficiency and safety .

Advantages

• Continuous, distributed monitoring along the entire cable length.
• Non-intrusive and immune to electromagnetic interference.
• Supports predictive maintenance and dynamic line rating.
• Enhances safety for both land and submarine power systems. In summary, Eastern European power systems utilize a combination of Raman-based DTS, DAS, and PMU-assisted models to monitor cable temperatures accurately. These systems integrate specialized optical fibers, measurement devices, and software platforms to provide real-time insights, optimize load management, and ensure the reliability of high-voltage transmission networks .