The Study Of Shore-to-Ship Power Technology And Automatic Synchronizing System

In recent years, with china’s economic rapidly growth, the shipping trade between china and foreign is large-scale expanding, more and more ships visit china’s port. Especially with the development of the shipbuilding technology and shipping needs, it appears more and more large-tonnage ships. The means that use shore power alternative ship generators is effective to reduce the air and noise emission cased by fuel burning in dock.Shore power technology can consist of Low-voltage(LV) shore power and High-voltage(HV) shore power. The output of low-voltage shore power system is440V or690V, and high-voltage shore power system is6.6kV or11kV. In this thesis, we discuss the basic structure of shore power and the distribution manner of the VVVF equipment located in land, comparing the advantages between low-voltage shore power and high-voltage shore power. High-voltage shore power can provide larger power. It is more convenience when connected to ship and it can be used in wide range. This thesis focuses on four kinds of overall structure of the HV shore power supply, analysis of its key technologies:high-power electronic inverter voltage technology, quickly connect technology and seamless switching technology.Seamlessly switching between shore power supply and ship generator can be done by the automatic synchronizing system. This thesis analyzes the process of shore power supply, grid synchronizing principle, and the four conditions of synchronizing, focusing on how to obtain the voltage, the frequency and the phase angle of Shore Power and ship power, studying the prediction of the phase angle method, the calculation of the closing angle and the capture of synchronous closing point. Considered the specially feature of the HV shore power supply, we explore the hardware design of the HV shore power automatic synchronizing system, design the main circuit, such as frequency acquisition circuit, phase angle acquisition circuit, A/D signal sampling circuit, and so on.Finally, based on the condition of synchronizing and operating procedures, we explore the software design. Considered the difference of operating procedures between in port and leaving port, this thesis studies the operating software flowchart of HV shore power synchronizing.