Research On Power Quality Monitoring Equipment Of Ship Integrated Power System

Modern ships are developing toward large-scale and intelligent,which increase the demand of ship electric energy,so as to promote the development of Ship Integrated Power System.However,the Ship Intergrated Power System has limited power generation capacities,the independent,nonlinear load of ship power system will impact the grid on ship.It is easy to cause the grid voltage fluctuation,sag and flicker and so on.Effective analysis of power quality parameters on ship will guarantee normal operation of vessels.This thesis conducts research on power quality of Ship Integrated Power System,and then designs ship power quality monitoring equipment which can be used to monitor power quality parameters of Ship Intergrated Power System.First,this paper explains the power quality problems of Ship Integrated Power System,analyzes the algorithm of power quality monitoring system and introduces the development status of power quality monitoring equipment at home and abroad.This paper gives the parameter calculation and measurement method by analysing the power quality parameter and index of ship grid.This system chooses windowed Fast Fourier Transform algorithm to enhance the accuracy of harmonic analysis of ship grid.Then,according to the requirements of power quality parameters measuresuremet on ship power grid,this paper proposes the hardware circuit scheme of monitoring equipment,which can be divided into the signal conditioning module,signal sampling processing module and man-machine interaction module.The main function of signal conditioning module is to transform voltage and current of grid into low electronic signal;the signal is captured and calculated by signal sampling processing module,at last the signal is displayed and stored through man-machine interaction module.This paper introduces DSP terminal program and ARM terminal program to match the hardware of the equipment.Main function of the DSP terminal program is to sampling signal,calculating power quality parameter and transmitting data;The ARM terminal program take Linux operation system as software platform,and take QT/Embeded software as interface development tools.It will improve the realiability and real-time capacity of the program.Finally,this paper designs a set of power quality monitoring equipment which can be used in the low voltage side of Ship Integrated Power System,and using the equipment to measure power quality parameter of gird by simulating the various load conditions in the laboratory.The test results show that the monitoring equipment can monitor the power quality parameters of Ship Integrated Power System.