Continuous condition monitoring of high voltage transformers by direct sensor monitoring of oil aging for a stable power network

The new online oil sensor system, OilQSens®, enables continuous condition monitoring and power grid protection of high voltage transformers by sensor monitoring of oil aging. The requirements for transformers in the renewable energy rise. Ever more flexibility at a maximum operational reliability and a long life are required of them at the same time, so the requirements for the transformer oil grow correspondingly. The new online oil sensor system OilQSens® measures the components conductivity kappa, dielectric constant epsilon r and temperature T independently and calculates the breakdown-voltage, loss angle tan delta, acidification, and it looks promising to calculate also the humidity. The new approach utilizes sensor detection of chemical aging of the insulating oil and its inhibitors. Based on a very sensitive measurement method with high accuracy even small changes in the conductivity and dielectric constant of the transformer oil composition can be detected reliably. The new sensor system effectively controls the proper operation conditions of High Voltage Transformers, oil-filled circuit breakers and oil regeneration systems.