The high-frequency current transformer is a sensor that can be widely applied to the partial discharge detection of various high-voltage electrical equipment such as transformers, cables, switchgear cabinets, GIS, generators, PT cabinets, and circuit breakers. It can be installed on the grounding wire of cable input bushings/surge capacitors, the grounding wire of cable bodies or shielding layers, the secondary winding of current transformers in switchgear, and the neutral line of generators and transformers. Its technology is in a leading position domestically.

How does a high-frequency current transformer detect partial discharge signals?

Partial discharge (PD) monitoring is now a widely recognized and adopted technical method for diagnosing the insulation condition of equipment internationally. This technology can also be used for routine inspections or on-site testing of other high-voltage equipment in substations. The vast amount of PD data and the complexity of on-site situations make real-time monitoring a challenging task.

When partial discharge occurs inside the cable, high-frequency current will propagate along the grounding wire to the earth. Partial discharge detection is achieved by installing a high-frequency current transformer on the grounding wire to detect high-frequency current signals. The high-frequency current transformer uses a Rogowski coil method, in which multiple turns of conductive wire coils are wound around a ring-shaped magnetic core material. The high-frequency alternating electromagnetic field caused by the high-frequency current passing through the center of the magnetic core induces an induced voltage in the coil. The measurement circuit of the high-frequency current transformer sensor is not electrically connected to the measured current, which belongs to a non-invasive detection method, and the device being tested does not need to be shut down.

Product Features

Ultra-wideband, high frequency

The sensor has excellent instantaneous response capability and can be widely applied to high-frequency current measurement

The sensor can be directly placed on the conductor being measured for measurement

Good linearity, high accuracy

The design features a retractable ring structure with a self-locking mechanism, ensuring easy, secure, and reliable installation

Measurement requires damaging the conductor, posing an open-circuit hazard

The shell is made of magnetic material, and the interior is encapsulated with epoxy resin in one-time casting

With a protection level of IP68, it can be used both indoors and outdoors in all weather conditions