Harmonic Analysis And Suppression For Power System Of Marine Electric Propulsion

The harmonic in the electric propulsion ship is analyzed and inhibited in this paper. With the development of the power electronic technology, power electronics device has been widely used in ships and the development of electric propulsion is booming. But at the same time power electronic equipment used in great quantities has brought ship power system harmonic problems increasingly, and directly affected the shipping safety and economy. For such a powerful shipbuilding and Marine country, in order to make rapid development in marine electric propulsion, the ship harmonic management will be the primary problem, and the analysis of the harmonic wave in the power grid to ship inhibition and technology research has profound significance.The paper firstly makes a thorough analysis of the source of ship harmonic, and studies the main influence and harm to power equipment, and has deduced harmonic losses formula. The paper also analyses the characteristics of dominant harmonics ship power system, and puts forward some commonly used harmonic analysis methods, compares the advantages and disadvantages of several harmonic control technology. This paper mainly puts forward using the harmonic shielding transformer instead of traditional ship electric propulsion transformer and using inductive filtering technique of harmonic converter device to undertake inhibition. The structure of harmonic shielding transformer and its harmonic control mechanism of the transformer is studied, and the traditional YΔconnection is improved to yanbianΔlink, and the filter unit is installed to the public value side of transformer windings place, through public winding zero impedance design, making the specific harmonic absorbed by filtering device instead of the ship grid side. With MATLAB software SIMULINK tool creates a harmonic shielding transformer based on 12 pulse rectifier ship power system. In order to reflect the advantages of harmonic shielding transformer harmonic control effect, the traditional ship electric propulsion system is simulated. Comparing the simulation test results, it proves the harmonic shielding transformer validity and feasibility of the harmonic control, effectively inhibit the harmonic infuse ship power system.