Modeling And Simulation Of A Multi-port MVDC Converter For Tidal Power Generation Systems

Tidal power is a predictable renewable energy resource which gives it a significant advantage over other renewable energy sources.To facilitate the integration of tidal power stations into the existing electricity grid.one option is to incorporate more DC grids into the system because they have lower losses and enhanced flexibility of renewable energy resources integration.There is also no need for frequency and phase tracking.The main aim of this work is to propose a multi-port DC-DC converter suitable for tidal power generation systems,intended to collect multiple DC tidal driven power and transfer the collected power to a 30kV DC distribution network.The state-of-the-art of multi-port DC-DC converters is analyzed in the literature review,and the key technologies are identified.A DC based tidal power conversion system is proposed,and the individual stages of the system is analyzed and simulated in MATLAB.An isolated multi-port DC-DC converter is proposed.which consists of multiple current-source inverters on the primary side and a 7-level modular multilevel rectifier on the secondary side.A 500Hz multi-winding transformer is used to increase the power density of the converter.A power transfer method which adopts phase-shift modulation is proposed and compared to a duty cycle variation technique.The performance of the proposed multi-port converter is analyzed from the simulation results.The results showed that the pulse width variation proved to be ineffective as the amount of power transferred did not change much with each scenario.The phase difference variation method on the other hand proved to be a very effective method of regulating the amount of power transferred...