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

High-frequency current transformer is a sensor that can be widely used for partial discharge detection of high-voltage electrical equipment such as transformers, cables, switch cabinets, GIS, generators, PT cabinets, circuit breakers, etc. of various electrical levels. It can be installed on the grounding wire of the cable input bushing/surge capacitor, the cable body or shielding layer grounding wire, the secondary winding of the current transformer in the switchgear, and the neutral wire of the generator and transformer. The technology is in a leading position in China.

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

Partial discharge monitoring is now a technical means of diagnosing the insulation condition of equipment that has been widely recognized and adopted internationally. This technology can also be used for routine inspections or on-site inspections of other high-voltage equipment in substations. The large amount of partial discharge data and the complex situation on site make real-time monitoring of it a challenging task.

When partial discharge occurs inside the cable, the high-frequency current will propagate to the earth along the ground wire. Partial discharge detection is achieved by installing a high-frequency current transformer on the ground wire to detect the high-frequency current signal. The high-frequency current transformer uses the Rogowski coil method, with multiple turns of conductive coils wrapped around the annular core material. The high-frequency alternating electromagnetic field caused by the high-frequency current passing through the center of the core will generate an induced voltage on the coil. There is no electrical connection between the measurement circuit of the high-frequency current transformer sensor and the current being measured. It is a non-invasive detection method, and the equipment being measured does not need to be shut down.

Product features:

Ultra-wideband, high frequency

The sensor has excellent instantaneous response ability and can be widely used in high-frequency current measurement

The sensor can be directly put on the conductor to be measured for measurement

Good linearity and high accuracy

Openable ring structure design, designed with self-locking device, easy installation, firm and reliable

Measurement requires destruction of the conductor, open circuit is dangerous

Magnetic shell, internal epoxy resin one-time casting and potting

Protection level reaches IP68, can be used indoors and outdoors all day