Analog computer solution of ship's deviation due to submarine d.c. cable

The magnetic field produced by a submarine d.c. power cable can cause appreciable deflection of a ship's magnetic compass. The effect on the ship's course depends on the parameters of the cable and the geometry of the ship's path relative to the cable. Depending on these factors the ship may suffer a deviation at right angles to its intended course though finally regaining its original heading, or it may be « capturedso that its course runs parallel to the cable. The describing equations can be solved on an analogue computer though some care is required in the design of the non-linear parts of the circuit. The experiment has been found valuable as part of the practical work in a Master's course on h.v.d.c. transmission.