Electric Deep-Sea Thrusters: The "Quiet Power Pioneers" of Deep-Sea Scientific Research

Among various power solutions for deep-sea exploration, electric deep-sea thrusters have become the preferred power equipment for scientific research submersibles and unmanned detection platforms, relying on their core advantages of "low noise, high efficiency, precise controllability, and structural reliability". From the deep-sea biological observation of the "Jiaolong" submersible to the 10,000-meter cruise of the "Haidou-1" unmanned submersible, this "power pioneer" has always provided stable support for deep-sea scientific research missions with its low-key yet reliable performance. The technological adaptation and innovative design behind it perfectly meet the rigorous requirements of deep-sea exploration for power systems.

The core working principle of electric deep-sea thrusters is not complicated: they are powered by deep-sea-adapted high-energy-density batteries to drive brushless DC motors, which in turn drive propellers to rotate and generate thrust, propelling the equipment to move in seawater. Compared with other types of thrusters such as hydraulic and jet thrusters, its most prominent advantage is "low noise" — the operating noise of brushless motors can be controlled below 100 decibels, equivalent to the ambient noise in a library. This can minimize interference with deep-sea organisms and avoid disrupting the submersible's acoustic detection equipment. This feature makes it an ideal power choice for tasks such as deep-sea biological observation and seabed acoustic mapping. For example, during the biodiversity survey at Caiwei Seamount in the Western Pacific, the "Jiaolong" submersible equipped with electric thrusters could quietly follow deep-sea fish schools and capture precious close-range image data.

To operate stably in extreme deep-sea environments, electric deep-sea thrusters need to overcome three major technical challenges. First is high-pressure sealing adaptation. Its motor compartment adopts a titanium alloy shell and a multi-layer redundant sealing design. The core sealing parts are made of a composite material of special ceramics and fluororubber. At the same time, hydraulic oil with a density similar to that of seawater is filled in the compartment to balance internal and external pressure, which can withstand the high pressure of 1,000 atmospheres in the 10,000-meter deep sea and prevent seawater from seeping in and causing motor short circuits. Second is anti-corrosion optimization. The surface of the thruster shell and propeller is sprayed with a ceramic-based composite coating, and key components are made of titanium-molybdenum alloy with extremely strong corrosion resistance, which can effectively resist the erosion of seawater salts and microorganisms and ensure stable performance under long-term immersion. Third is efficient energy utilization. It uses special high-energy-density lithium batteries combined with an intelligent energy management system, which can dynamically allocate electrical energy according to mission requirements, reduce power to save energy during cruising, and accurately output thrust during sampling, greatly improving endurance.

The characteristic of precise controllability makes electric deep-sea thrusters the "core assistant" for refined scientific research tasks. Its thrust adjustment accuracy can reach the millinewton level, and combined with a multi-thruster coordinated control system, it can achieve complex movements such as centimeter-level hovering, in-place rotation, and oblique translation. The "Fendouzhe" (Striver) manned submersible is equipped with 6 main electric thrusters and 4 fine-tuning electric thrusters. When collecting rock samples at the 10,000-meter seabed, the fine-tuning thrusters can accurately offset the reaction force of the sampling tools, keeping the submersible motionless; in terrain mapping tasks, multi-thruster coordinated control can ensure the equipment moves smoothly along the preset route and obtain high-precision seabed terrain data.

With the in-depth development of deep-sea exploration, electric deep-sea thrusters are upgrading towards the direction of "miniaturization, high power, and intelligence". Researchers optimize the motor structure and adopt new nanocrystalline alloy materials to reduce volume while improving thrust density; combined with artificial intelligence technology, the thrusters can independently identify changes in ocean currents and automatically adjust working parameters to offset interference. In the future, with the maturity of technologies such as solid-state batteries and wireless power supply, electric deep-sea thrusters will achieve longer endurance and more flexible operations, continuing to serve as the "main power" for deep-sea scientific research and helping humanity unlock more mysteries of the deep sea.