Study On The Cathodic Protection Power Supply Intellectualized Monitor System Based On LabVIEW

Impressed Current Cathodic Protection (ICCP) is one of the most important methods to delay and prevent electrochemical corrosion of the underground or underwater metal structures. The impressed DC power supply is an important part of impressed current cathodic protection. Based on virtual instrument technique and computer control technique, the paper develops an intelligentizing and networking control system of cathodic protection power supply, which is suitable for long-distance centralized control and easy to operation and lower cost and excellent capability.The main research content of the dissertation involves:(1) The paper analyzes output voltage, output current, the protected structure potential measured by dint of reference electrode as well as the potential of the two key points in the protected structure, all of which are indexes to measure the protection effects. The appropriate sensor which is one part of the system hardware is chosen.(2) The reasonable and economical power supply circuit is designed, including the primitive scheme and the easy-realized alternative scheme.(3) The paper analyzes the advantage of virtual instruments compared with traditional instruments. Combining computer control technique and database technique with virtual instrument technique, the paper develops a software to manage the monitor system of cathodic protection power supply. Meanwhile, data transmission module is designed to real-time collect the parameters of the power system as well as control the executive mechanism of the circuit.(4) The paper discussed how to design the basic function module, which provides the parameters setting interface to set the collecting interval, objective value, the coefficient of the algorithm and alarm parameter, etc. Referred with the cathodic protection knowledge base, the parameters of the system can be real-time set so that the power can be automatic monitored effectively.(5) The paper utilizes Microsoft Access as database to manage the data in the LabVIEW. There are two classes of tables in the database: history data and objective value tables and the knowledge base table. The data in the database can be added, searched and deleted. (6) Also, the system can be controlled in long distance. With the Web Publishing tool of LabVIEW, the system can be published in the web so that remote client can monitor and control the system through browser. This is the true virtual instruments actually.