Shipboard Power Distribution Systems Research Articles

Power flow analysis of DC distribution system in a ship with non-electric propulsion

<span lang="EN-US">Direct current (DC) shipboard power distribution system offers higher power efficiency and voltage stability compared to the alternating current (AC) systems due to lower impedance. The implementation of DC distribution system in all-electric ship seems to be worthy since the reduction of power loss and voltage drop could overcome the drawback of DC system. However, the effectiveness of DC distribution system in ship with non-electric propulsion has not been investigated yet. Unlike in an all-electric ship, electric power flow in the distribution system of a ship with mechanic propulsion is considerably lower. The study aims to provide numerical analysis of power loss and voltage drop reduction on DC distribution system that applied to a ship with mechanic propulsion. The power flow analysis is performed on a tanker ship. Contrary to the hypothesis, the results show that the DC power distribution increase the power losses about 15% compared to AC system due to the addition of rectifier and inverter. However, the voltage drops are decreased in DC distribution system. Further investigation in the other aspects should be performed before concludes whether DC distribution system is worthy to be used in the aforementioned ship.</span>

Analysis of Circuit Design of a Rowing Electric Installation with a Distributed DC Bus of a Port Icebreaker

Currently, there is a steady trend in increasing the volume of electrical equipment used in shipboard needs. At the same time, the primary electric power system of ships has long been based on an alternating current system. However, due to the changing and increasing requirements for the quality of the generated electric energy, the marine industry is developing more and more promising directions for the development of electrical systems. Thus, the most efficient and environmentally friendly shipboard power distribution system is the direct current (DC) system, which was adopted for a single power plant installation in combination with an alternating current network. This article discusses the current topic of electric propulsion on ships. The circuit design of a rowing electric installation with a distributed DC bus of a port icebreaker is considered. The expressions used to calculate the static load and build an electromagnetic model of a permanent magnet synchronous motor are given. Computer models for calculating the load in static and dynamic modes are shown.

Solid State Transformers for Ship’s Electrical Power System

Traditional transformers have an important role and a long history of use in shipboard power distribution systems. The introduction of fully integrated electrical propulsion systems and other high power nonlinear loads onboard modern vessels, together with increased number of ports with high voltage shore connection systems, causes considerable power quality issues which also affect the operation and the design process of traditional power transformers. Some of the challenges and shortcomings of conventional transformers can be partially overcome by using solid state transformers (SST). Thanks to the availability of advanced power semiconductor devices capable of handling medium voltage levels, there is a significant growth in the use of the SST technology in the smart-grid and traction application. This paper has analysed the possibility of SST implementation on ships.

Study of Shipboard Power Distribution System: Review on an Aplication of AC Zonal Distribution

The shipboard power distribution system has been developed in order to make it more efficient. AC zonal distribution system is one of the options in order to achieve the objection. This study aims to observe the shipboard application with AC zonal distribution system. The distribution system is modeled, simulated, analyzed, and compared with conventional system. Based on simulation, the AC zonal distribution system provide higher reliability, better power continuity, and more stable power generation. Therefore, development of the zonal distribution system continues to bring succeed in every mission. However, the system has several challenges for future work such as more complex transmission system, higher voltage drops, and the tendency to have instability power distribution when one generator fails.

Study of Shipboard Power Distribution System: Review on an Aplication of AC Zonal Distribution

The shipboard power distribution system has been developed in order to make it more efficient. AC zonal distribution system is one of the options in order to achieve the objection. This study aims to observe the shipboard application with AC zonal distribution system. The distribution system is modeled, simulated, analyzed, and compared with conventional system. Based on simulation, the AC zonal distribution system provide higher reliability, better power continuity, and more stable power generation. Therefore, development of the zonal distribution system continues to bring succeed in every mission. However, the system has several challenges for future work such as more complex transmission system, higher voltage drops, and the tendency to have instability power distribution when one generator fails.

Modeling and analysis of a flywheel energy storage system for Voltage sag correction

The U.S. Navy is looking for methods to maximize the survivability of combat ships during battle conditions. A shipboard power distribution system is a stiff isolated power system that is vulnerable to voltage sags, which arise due to faults or pulsed loads, which can cause interruptions of critical loads. A series voltage injection type flywheel energy storage system (FESS) is used to mitigate voltage sags and maximize the survivability of the ship. The basic circuit consists of an energy storage system, power electronic interface, and a series injection transformer. In this case, the energy storage system consists of a flywheel coupled to an induction machine. The stored energy is used for sag correction for the critical load. Indirect field-oriented control (IDFOC) with space-vector pulsewidth modulation (SVPWM) is used to control the induction machine. Sinusoidal PWM is used for controlling the power system side converter. This paper presents the modeling, simulation, and analysis of a FESS with a power converter interface using PSCAD/EMTDC.

Network reconfiguration for service restoration in shipboard power distribution systems

Network reconfiguration for service restoration in shipboard power distribution systems

Fault protection on shipboard A-C power-distribution systems

THE growth in the use of electrically driven auxiliaries on shipboard has produced very large increases in the installed generating capacity. This fact together with the necessity for maintaining a high degree of reliability and continuity of service in shipboard powerdistribution systems has emphasized the importance of providing adequate fault protection. Such protection is concerned primarily with the automatic isolation of a fault with minimum damage and with minimum disturbance to the remainder of the system. It is the purpose of this paper to develop some of the fundamental considerations in fault protection on shipboard and to establish the basic principles and methods for the selection and arrangement of the various protective devices to achieve a complete and co-ordinated protective system. The discussion will be restricted to low-voltage (600 volts or less) a-c systems although many of the principles are also equally applicable to d-c systems.

Fault Protection on Shipboard A-C Power-Distribution Systems

THE growth in the use of electrically driven auxiliaries on shipboard has produced very large increases in the installed generating capacity. This fact together with the necessity for maintaining a high degree of reliability and continuity of service in shipboard powerdistribution systems has emphasized the importance of providing adequate fault protection. Such protection is concerned primarily with the automatic isolation of a fault with minimum damage and with minimum disturbance to the remainder of the system. It is the purpose of this paper to develop some of the fundamental considerations in fault protection on shipboard and to establish the basic principles and methods for the selection and arrangement of the various protective devices to achieve a complete and co-ordinated protective system. The discussion will be restricted to low-voltage (600 volts or less) a-c systems although many of the principles are also equally applicable to d-c systems.