High-voltage insulation monitoring sensors are specialized devices designed to continuously assess the health of electrical insulation in power equipment like cables, transformers, and switchgear. Their operation is primarily based on measuring leakage current and dielectric loss. A common method involves using a high-precision current sensor to measure the tiny capacitive leakage current flowing through the insulation system to ground. By analyzing parameters like the current's amplitude, phase shift relative to the voltage (which indicates the loss factor tan δ), and the presence of harmonics, the sensor can evaluate the insulation's integrity and detect moisture ingress, aging, or contamination.
Product Features
1. Real-Time Continuous Monitoring: They provide non-stop, real-time data on insulation conditions, enabling predictive maintenance and early fault detection, a significant improvement over traditional periodic offline testing.
2. High Sensitivity to Early Degradation: Capable of detecting minute changes in leakage current and dielectric loss factor, which are early warning signs of insulation breakdown long before a complete failure occurs.
3. Enhanced Grid Reliability and Safety: By providing early warnings, they help prevent unplanned outages, equipment damage, and potential safety hazards associated with insulation failure, thus improving the overall reliability of the power system.
Common Applications
These sensors are critical for modern condition-based maintenance strategies in electrical networks:
1. Power Transformers and Bushings: Monitoring the condition of oil-paper insulation and bushing integrity.
2. High-Voltage Cables and GIS (Gas-Insulated Switchgear): Tracking insulation aging and detecting partial discharge activity.
3. Generator and Motor Windings: Providing early detection of insulation weakening in critical rotating machinery.
