HYBRID ELECTRICITY SYSTEMS OF VESSELS WITH DC-GRID SYSTEM
Reduction of the resources consumption for generating the electric power, improving the parameters of a vessel electric network is one of the purposes of sea transport development. A direction of researches is hybridization of generation sources and the electric energy accumulation devices. The given concept is based on division or simultaneous use of several various energy sources, the choice and combination of which are intended for improving the power systems parameters. The overwhelming majority of modern sea-crafts use the systems of distribution of an alternating current. However, with introduction of power electronic converters into the power supply systems, the direct current networks with integration of sources and devices for accumulating electric energy, connected to a distributed DC bus, are increasingly being used in the fleet. This direction is one of the decisions for fuel consumption minimization, especially, for the vessels demanding high degree of maneuverability and various running cycles. The possibilities of a ship hybrid electric power system are defined in the paper. Comparison of various architectures of the given system is performed. The block diagram of the hybrid electric power system is considered. Formulas for calculating static load are given. The equations describing electromagnetic processes of the asynchronous electric motor as the propulsion electric motor are written down. The device for accumulating electric energy is considered. The calculation of the energy released by the propulsion electric motor during braking or reverse, which can be directed both to the braking resistor and stored in special systems of electric energy storage. The computer model of considered hybrid electric power installation on the basis of computer program SimInTech is made.