Improvement And Optimization Of Switching Power Converter For Cathodic Protection

In the reform and opening up the big situation,China’s economy is witnessing a rapid development.Large scale hydropower plants,coastal nuclear power plants,large scale ship projects and so on are all required to apply large-scale metal corrosion protection technology.Therefore,the development of cathodic protection technology plays a very important role of China’s economic development.The cathodic protection system is composed of three main structures,which are power supply equipment,auxiliary anode and reference electrode.The power part as a whole system of "heart" is particularly important,especially in today’s increasingly serious energy problems,this part of the design has been widely concerned.With the development of power technology,phase shifted full bridge soft switching circuit is widely used in the cathodic protection system with its high converter efficiency,low power device voltage and current stress and simple structure.Cathodic protection system needs to be applied in high power applications,and the energy consumption of the system is the key to the design and quality of the system.In addition,the system is used in the outer surface of the ship,which contacts with sea water.In order not to affect the normal navigation,it is often required that the system is more compact and portable.In this dissertation,the working process of phase shifted full bridge circuit used in the power supply of cathodic protection was studied.The research involved the secondary side rectifier circuit parasitic oscillation,suppression measures and etc.The main innovations of this dissertation include:1.In this dissertation,the reverse recovery process and the loss of duty cycle of the full bridge phase shift circuit were studied.In view of these problems,this dissertation used the saturation inductance in the branch of the side rectifier tube,and discussed the working principle and design scheme of the saturated inductor.This part mainly introduced the soultion of parasitic oscillation and the loss of duty cycle of the phase shifted full bridge circuit in high power applications.2.This dissertation analyzed the principle and characteristic of the general synthetic core and made some improvements.What’s more,the working process of this new type of synthetic magnetic core was discussed by using the capacitance model,and the simulation results were verified by Maxwell.At the end of the dissertation,the summary and prospect were summarized,which pointed out the shortcomings of this dissertation and the need to be improved.