Current limiter

A current limiter for selectively limiting a rate of change of a fault current in a DC electrical network, the current limiter comprising:

• a first electrical block including an inductive element;
• and
• a second electrical block including a bidirectional switch, the first electrical block being connected in parallel with the second electrical block between first and second terminals, the first and second terminals being connectable to the DC electrical network,
• wherein the bidirectional switch is switchable to a first mode to permit current flow through the second electrical block in a first current direction and at a same time inhibit current flow through the second electrical block in a second current direction, the first and second current directions being opposite to each other, and the bidirectional switch is switchable to a second mode to permit current flow through the second electrical block in the second current direction and at a same time inhibit current flow through the second electrical block in the first current direction, and
• wherein the current limiter further includes a controller to control the switching of the bidirectional switch to each of the first and second modes, and the controller is configured to selectively control the switching of the bidirectional switch to either of the first and second modes while a fault current is flowing through the current limiter, to enable the second electrical block to form a current path that allows current to freewheel around a loop formed by the first and second electrical blocks and thereby allows the fault current to fall at a higher rate than it would do in the absence of the current path.