Innovative SF6 free switch with shunt vacuum interruption technology

This paper presents an innovative and compact SF6 free switch with shunt vacuum interruption (SVI) technology. To replace SF6 as arc-quenching gas, some alternative fluorinated candidates were identified for medium voltage electrical equipment. 
While their GWP (Global Warming Potential) is low, these gases require specific precautions for handling and end of life management. Indeed, the acute 
toxicity of these gases is high, their carcinogenic, mutagenic and reprotoxic characteristics are not known and, when exposed to electrical arcs, they produce numerous toxic by-products.
A smart solution has been designed without breaking in gas. The gas inside the switchgear has only a dielectric function and then any by-products after current breaking is avoided. The dielectric performance is insured by air or HFO 1234zeE at different pressures according to voltage rating. The breaking is ensured by vacuum interrupters whose role consists in shunting the current from the main circuit then breaking during the phase of opening. 
Disconnection is ensured by a gas gap and earthing is done inside the tank. 
The operating mode is the same as current SF6 3-positions switch: breaking/disconnecting in one operation and earthing in a second operation. The combination of different devices and their interactions enable to design a compact solution with similar dimensions than SF6 ones. 
This solution presents the following advantages: fully environmentally friendly, safe for people, easy to operate, high expecting life and same footprint as current SF6 switchgear.