Hybrid switching apparatus of the withdrawable type

A switching apparatus for electric power distribution grids comprising:

• one or more first and second line terminals electrically connectable to corresponding first and second line conductors of an electric line, respectively;
• a first switching unit having one or more first electric poles, each first electric pole comprising a first pole contact electrically connectable to a corresponding first line terminal, a second pole contact and one or more solid-state switches electrically connected to said first and second pole contacts and adapted to operate in a conduction state or in an interdiction state to allow or interrupt a current flow,
• wherein said first switching unit is reversibly switchable between a closed condition, in which said solid-state switches are in a conduction state, and an open condition, in which said solid-state switches are in an interdiction state,
• wherein said first switching unit is reversibly movable between an insertion condition, in which said first pole contacts are coupled with said first line terminal, and a withdrawal condition, in which said first pole contacts are uncoupled from said first line terminals;
• a second switching unit having one or more second electric poles, each second electric pole comprising a third pole contact electrically connectable to a corresponding second pole contact of the first switching unit, a fourth pole contact electrically connectable to a corresponding second line terminal and electric contacts electrically connected to said third and fourth pole contacts and adapted to operate in a coupled state or on an uncoupled state to allow or interrupt a current flow,
• wherein said second switching unit is reversibly switchable between a closed condition, in which said electric contacts are in a coupled state, and an open condition, in which said electric contacts are in an uncoupled state,
• wherein said second switching unit is reversibly movable between an insertion condition, in which said fourth pole contacts are coupled with said second line terminals, and a withdrawal condition, in which said fourth pole contacts are uncoupled from said second line terminals;
• a controller adapted to control the operation of said switching apparatus;
• a power supply stage adapted to receive an external power supply;
• said controller is configured to control said first and second switching units, so that both said first and second switching units are in an open condition, when said power supply stage is subject to a fault condition.