Objectives  In order to realize the rapid and convenient deperming of ships, a new design scheme for the coil system of an overrun deperming station is proposed.

  Methods  Simulation models of the coil system are built, including the vertical compensation coil, horizontal compensation coil and vertical working coil, and the simulation analysis is performed by using software MagShip.

  Results  The vertical compensation coil can produce an 80 A/m vertical compensation magnetic field with uniformity of about 95%;the horizontal compensation coil can produce a 40 A/m horizontal compensation magnetic field with uniformity of about 95%;and the combination of both coils can compensate for the geomagnetic field in depermed ships. The vertical working coil can produce an alternating working magnetic field of more than 2 000 A/m, providing working energy for the deperming of ships.

  Conclusions  The numerical simulation results show that the proposed deperming coil design scheme can not only compensate for the geomagnetic field but also produce an alternating magnetic field sufficient for realizing the deperming of a ship, which verifies the feasibility of the proposed coil system design. The results of this paper can provide useful theoretical guidance in the design of coil systems for overrun deperming stations.