Study On Shore-based Constant Current Power Supply For Ocean Observatory System

The ocean occupies about 71% of the earth’s surface area and contains very rich resources.Due to its special environment,humans’ understanding of the ocean still has certain limitations.In recent years,with the rapid development of the world economy,our understanding of marine disaster prevention,marine rights protection,marine economy and other fields has become deeper and deeper,and the concept of ocean observatory system has emerged as the times require.With the maturity of related technologies,the scale of ocean observatory system is also expanding.Long-distance ocean optical cable transmission networks with relays have problems such as difficulty in power supply and high requirements.In view of the special power supply environment of the ocean observatory system,the constant current power supply technology has the advantages of better fault resistance,robustness and reliability due to keeping the current constant,and is more suitable for the remote power supply of the ocean observatory system.This article will combine the remote power supply mode of the ocean observatory system to carry out detailed design analysis of the shore-based power supply.The full-bridge series resonant converter is used as the main circuit topology to achieve constant current output.At the same time,the input parallel output series(IPOS)combined converter technology is used to meet the requirements.Actual power requirements.In order to avoid the shore-based power supply causing frequency interference to the ocean optical cable communication system,this paper combines the phase-shift control technology to realize the constant current output of the full-bridge series resonant converter.The output current is sampled by the sampling resistor to obtain the output current signal,which is then combined with the reference signal.The error signal is compared and the phase shift angle is adjusted according to the error signal,which can realize the zero-voltage turn-on of the switching tube in the full load range,reduce switching loss,and improve the efficiency of the converter;at the same time,a detailed analysis of its working process is carried out.Fundamental wave analysis method models and analyzes the main circuit topology,which provides a theoretical basis for the subsequent parameter design.Since the parameters of each module cannot be completely consistent,in order to ensure that the input parallel output series(IPOS)combined converter of constant current output can work stably,it is necessary to realize the input current sharing and output voltage sharing of each module.This article first reveals the relationship between input current sharing and output voltage sharing of a constant current output input parallel output series(IPOS)combined converter,and at the same time,a simulation circuit is built to verify and analyze the influence of the difference of each module parameter on the output voltage.On this basis,a control strategy of the maximum voltage autonomous voltage equalization method is proposed,and the working principle of the control strategy is analyzed in detail.According to the proposed principle and control strategy,the parameter design and hardware circuit design are carried out.The simulation analysis is carried out by building a simulation circuit.Finally,the corresponding experimental prototype is built for experimental verification.The experimental results show the constant current output theory and output voltage equalization control proposed in this paper.The plan is correct and effective.