This product innovation encapsulates the extensive know-how of PFISTERER, the world's only manufacturer of pluggable bushings for the HV sector.
Mobile power transformers must be compact so that, in the event of a power failure, they can easily be transported by truck to the required site. HV-CONNEX Size 7-S facilitates the construction of transformers with such a space-saving design. This is because the plug-in CONNEX bushing requires only one third of the length that a conventional bushing requires for discharging the field control inside the transformer. This enables the CONNEX device connection component, by means of which the bushing is plugged in, to be integrated in the cover of the transformer and constructed in a compact cubic form. In addition, the bushings can simply be removed and transported separately if required.
Fast and secure
Mobile emergency transformers using the CONNEX connection system can be installed quickly and reliably. A transformer equipped with the CONNEX connection system is pre-tested at the factory, together with its bushings, so that it no longer has to be opened on site. This completely does away with the need for the oil or gas work normally required in conventional systems and reduces the time required for the initial installation by up to 75 percent. The replacement of a bushing is equally effortless. The bushing to be replaced is simply unplugged and a new one inserted --- without the need for any oil processing.
High current-carrying capacity
Specifically for the HV-CONNEX Size 7-S bushing, PFISTERER uses a new production method, in which the silicon is applied to a glass fibre reinforced plastic cylinder, rather than directly onto the RIP body. This gives additional protection to the insulation body inside the bushing. A further special feature of the Size 7-S compared to existing CONNEX bushings is the high current-carrying capacity that reaches a rated voltage of 2,000 Amperes. In addition, the bushing and device connection component can be used in mineral oil, synthetically manufactured and natural ester oil.
The new bushing is suitable for power transformers and gas-insulated switchgear (GIS) up to 362 kV. It has been tested to IEC 60137 and also approved for the North American market. In the next phase, the pluggable bushing will be developed further for the 420 kV voltage level predominant in Europe. As the bushing is always backwards-compatible, it can already be used in all markets with voltage levels below 362 kV.