A plurality of switching cells for a phase leg of a power converter, each switching cell comprising: a power switch (MAIN SWITCH) for conducting a current for driving a load; a series connection comprising an auxiliary switch (AUX SWITCH) and a cell capacitor (CELL CAPACITOR) coupled in series, the series connection coupled in parallel with the power switch (MAIN SWITCH); and a cell inductor (CELL INDUCTOR) coupled to a coupling of the power switch (MAIN SWITCH) and the series connection, wherein each switching cell has a commutation loop to conduct a commutation current arising from turn-off of the power switch (MAIN SWITCH), the loop comprising: a first bypass circuit for blocking current flow in a direction and coupled in parallel with the power switch (MAIN SWITCH) to conduct a said commutation current in opposite direction; a second bypass circuit for blocking current flow in a direction and coupled in parallel with the auxiliary switch (AUX SWITCH) to conduct a said commutation current in opposite direction; characterized in that each switching cell comprises at least one control input line for receiving a control signal, the at least one control input line configured to drive a control terminal of the power switch (MAIN SWITCH) and a control terminal of the auxiliary switch (AUX SWITCH); wherein the plurality of switching cells form a phase arm of the phase leg of the power converter and wherein at least two switching cells of the plurality of switching cells are coupled in series and wherein the said cell inductor (CELL INDUCTOR) of the first switching cell of the at least two serially coupled switching cells is directly coupled to a coupling of the power switch (MAIN SWITCH) and the series connection comprising the auxiliary switch (AUX SWITCH) and the cell capacitor (CELL CAPACITOR) of the second switching cell of the at least two serially coupled switching cells. a power switch (MAIN SWITCH) for conducting a current for driving a load; a series connection comprising an auxiliary switch (AUX SWITCH) and a cell capacitor (CELL CAPACITOR) coupled in series, the series connection coupled in parallel with the power switch (MAIN SWITCH); and a cell inductor (CELL INDUCTOR) coupled to a coupling of the power switch (MAIN SWITCH) and the series connection, wherein each switching cell has a commutation loop to conduct a commutation current arising from turn-off of the power switch (MAIN SWITCH), the loop comprising: a first bypass circuit for blocking current flow in a direction and coupled in parallel with the power switch (MAIN SWITCH) to conduct a said commutation current in opposite direction; a second bypass circuit for blocking current flow in a direction and coupled in parallel with the auxiliary switch (AUX SWITCH) to conduct a said commutation current in opposite direction; characterized in that each switching cell comprises at least one control input line for receiving a control signal, the at least one control input line configured to drive a control terminal of the power switch (MAIN SWITCH) and a control terminal of the auxiliary switch (AUX SWITCH); a first bypass circuit for blocking current flow in a direction and coupled in parallel with the power switch (MAIN SWITCH) to conduct a said commutation current in opposite direction; a second bypass circuit for blocking current flow in a direction and coupled in parallel with the auxiliary switch (AUX SWITCH) to conduct a said commutation current in opposite direction; characterized in that each switching cell comprises at least one control input line for receiving a control signal, the at least one control input line configured to drive a control terminal of the power switch (MAIN SWITCH) and a control terminal of the auxiliary switch (AUX SWITCH); wherein the plurality of switching cells form a phase arm of the phase leg of the power converter and wherein at least two switching cells of the plurality of switching cells are coupled in series and wherein the said cell inductor (CELL INDUCTOR) of the first switching cell of the at least two serially coupled switching cells is directly coupled to a coupling of the power switch (MAIN SWITCH) and the series connection comprising the auxiliary switch (AUX SWITCH) and the cell capacitor (CELL CAPACITOR) of the second switching cell of the at least two serially coupled switching cells.