Research On Contactless Hybrid Transmission Of Power And Data Based On Underwater Anchor Chai

Ocean buoy observation platform is widely used in seawater data monitoring.Its underwater part is mainly composed of anchor chain steel cable and information acquisition node.The contactless power transmission technology is adopted in the underwater anchor tether,which can realize the continuous and stable power supply of underwater nodes.However,due to the seawater medium in one section of the transmission channel,the power transmission efficiency is low.At the same time,in order to ensure the real-time monitoring of marine information and improve the performance of data transmission,the synchronous hybrid transmission of electric energy and data is a key problem to be solved urgently.Therefore,the article studies the hybrid transmission of underwater contactless electric energy and data.The main research contents and results are as follows:Firstly,the characteristics of the inductive coupling anchor tether channel are analyzed.There is eddy current loss in the power transmission in the seawater channel.The analytical formula of the loss is derived,and the seawater impedance is introduced to express the influence of the loss on the power transmission;Secondly,the contactless power transmission circuit with seawater loss is analyzed,and the power transmission efficiency equation is derived;The matching equations among frequency,inductance and load resistance are obtained by theoretical analysis,the parameter calculation of maximum power transmission efficiency is simplified,the multi node model of underwater contactless power transmission is established,and the optimal design scheme of power transmission system is obtained.On this basis,the data transmission circuit is added,and the gain equation of data signal in the hybrid transmission circuit and the influencing factors between power transmission circuit and data transmission circuit are obtained.In order to better realize the mixed transmission of electric energy and data signals,a data transmission structure of magnetic ring and high pass filter is proposed in the article.Compared with the traditional resonance mode,this structure reduces the impact on the efficiency of electric energy transmission and enhances the ability to extract data signals from electric energy.Aiming at the frequency splitting phenomenon caused by the inductance of the magnetic ring on the filter,the key parameters of the magnetic ring are optimized.The circuit and parameters are verified by simulation analysis,which proves the feasibility of the frequency division multiplexing transmission scheme of data and power signal proposed in the article.Finally,a set of non-contact hybrid transmission prototype of electric energy and data of underwater anchor tether is designed and manufactured.Through experiments,it is verified that the transmission efficiency reaches 56%when the total input power of electric energy is 124W;When the mixed transmission of 50k Hz/1.55A electric energy and 400k Hz/10m A data is adopted,the reliable transmission of data is realized after 60db attenuation of electric energy.When the signal-to-noise ratio is 6d B,the bit error rate reaches 10^-3.The article presents a hybrid transmission scheme of electric energy and data suitable for underwater anchor tether,which has a certain reference and reference significance for seawater data monitoring.