Abstract: A novel electromagnetic jettison system without an armature was developed to resolve and complete the self-compensating buoyancy regulation of the towed marine profile buoy.In this paper,the design parameters of DC plunger electromagnet were determined through the theoretical analysis and calculation of the electromagnet structure,and the simple and reliable power trigger circuit was designed according to the analysis of the power supply characteristics of the electromagnet.Then,multiple experiments of the prototype were done to test its performance.The results show that this design meets the requirements,which verifies the feasibility of this proposal.In conclusion,comparing with the electromagnet with an armature,the proposed device has many advantages,such as simple structure,low power consumption,easily sealing,and so on.Therefore,it can be applied for the buoyancy regulation of small-scale towed buoy and also can provide references for the jettison system of other underwater equipments.

Key words: towed buoy, buoyancy regulation, electromagnetic jettison, trigger circuit