Electric Ship Propulsion Research Articles

전기추진선의 최대추력 운항을 위한 추력손실 억제에 관한 연구

This paper presents the thrust loss suppression algorithm in the electric propulsion ship. The thrust loss due to cavitation can be regarded as the disturbance torque. The disturbance torque is estimated by means of the disturbance observer. Considering the estimated disturbance torque, the speed reference of the propeller is modified to suppress the thrust loss. The experimental results which performed in the cavitation tunnel with electric machine operating system and its controller will be shown to verify the proposed algorithm.

Optimal placement and sizing of harmonic filters aboard an electric propulsion ship

An optimisation technique using simulated annealing is described, in order to find the best placement of the harmonic filters to be installed in a distribution system with their minimum power size. The filtering currents are then calculated not to cancel the resulting harmonic voltages but to reduce their values with respect to the fixed limits. The objective is to minimise the power size in view of maximum savings in the equipment cost. The aboard power system of an electric propulsion ship with a great number of nonlinear loads is analysed in order to illustrate the efficiency of the optimisation method.

Rotor flux oriented control of a symmetrical six-phase induction machine

Basic concepts of six-phase ac motor drives have been in existence for a number of years and were considered extensively in the eighties for safety-critical and/or high power applications. There has been an upsurge in the interest in these drives in recent times, initiated by various application areas, such as ‘more-electric’ aircraft, electric ship propulsion and EV/HVs. All the existing work considers an asymmetrical six-phase ac machine, with two sets of three-phase windings shifted in space by 30° (dual three-phase, split-phase, double star). In contrast to this general trend, a symmetrical six-phase induction machine, with spatial displacement between any two consecutive phases equal to 60°, is discussed in this paper. A vector control algorithm, based on indirect rotor flux orientation, is at first briefly described. Special attention is paid next to the current control issue, from the point of view of the minimum number of current controllers. An overview of the experimental test bench that utilises phase current control in the stationary reference frame is further given. Attainable performance is analysed experimentally and the results are presented for a number of operating regimes, including acceleration, deceleration, reversing and step loading/unloading transients. It is demonstrated that the achievable quality of high performance is excellent, while the standard benefits of the multiphase motor drives are retained.

The Performance of a 5 MW High Temperature Superconductor Ship Propulsion Motor

A 5 MW, 230 RPM, 6-pole high temperature superconductor (HTS) ship propulsion motor is presently under test at the Center for Advance Power Systems (CAPS). This paper provides a summary of the key design features of the motor, predicted performance, factory test results and extended test results to date at CAPS. This motor was designed and built under the U.S. Navy's Office of Naval Research (ONR) funding (Contract #N00014-02-C-0190) to address the next generation of electric ship propulsion systems. HTS motors are characterized by high power density, quiet operation and high efficiency. HTS air-core motors have unique electrical characteristics and therefore require dynamic testing to validate all modes of operation. The test program at CAPS is designed to address dynamic performance and simulation of this class of propulsion motor. The motor has been operated at 5 MW load for over 3 hours at CAPS.

Super Conductors On The High Seas - A superconductor motor makes its bid for electric ship propulsion.

Super Conductors On The High Seas - A superconductor motor makes its bid for electric ship propulsion.

The Importance Degrees’ Propulsion Of Equipment In Electric Propulsion Ship

The Importance Degrees’ Propulsion Of Equipment In Electric Propulsion Ship

99/03908 Testing of a sodium/nickel chloride (ZEBRA) battery for electric propulsion of ships and vehicles: Kluiters, E. C. et al. J. Power Sources, 1999, 80, (1/2), 261–264

99/03908 Testing of a sodium/nickel chloride (ZEBRA) battery for electric propulsion of ships and vehicles: Kluiters, E. C. et al. J. Power Sources, 1999, 80, (1/2), 261–264

Testing of a sodium/nickel chloride (ZEBRA) battery for electric propulsion of ships and vehicles

One of the promising future batteries for electric propulsion of vehicles and ships is the sodium/nickel chloride or ZEBRA (Zero Emission Battery Research Activities) battery. Despite some disadvantages with respect to the high temperature, the advantages with respect to specific energy and energy density are such that, especially in applications where the battery is used on a more or less continuous basis (e.g., in delivery vans and taxies) it is an interesting candidate battery. Another interesting application is on board of ships, like submarines or future electrical surface ships with electric propulsion. In 1995 a 2 year feasibility study, including experimental testing of a 10 kW h battery, was completed. This investigated the naval applicability of the sodium/sulphur battery, which is also a high temperature battery. Here the limited, experimentally proven, life-time of the batteries of about 1.5 years and this made naval application almost impossible. A paper about this study was presented at the 19th International Power Sources Symposium held at Brighton, England, in April 1995 [R.A.A. Schillemans, C.E. Kluiters, Sodium/sulphur batteries for naval applications, in: A. Attewell, T. Keily (Eds.), Power Sources 15, International Power Sources Symposium Committee, Crowborough UK, 1995. p. 421.]. Because of the more or less comparable specifications on specific energy and the more promising results of the life-time and field tests with sodium/nickel chloride batteries, a ZEBRA battery from AEG Anglo Batteries has been tested for naval applications. This was done by simulating the charge and discharge as it occurs in practice for the applications investigated. With respect to the electrical ship application (investigated for the Royal Netherlands Navy) the power versus time taken from the battery was simulated as well as the charge procedures. The same can be done for the vehicle application: in this case typical drive cycles for a van or taxi are translated to power versus time taken from the battery. The results of the tests for application of the battery in naval ships are very promising.

Technology Development for Electric Ship Propulsion

An overview of the current and projected state of the art for marine electric drive systems is presented, together with an assessment of relative development risk. The objectives for pursuing development of electric drive are arrangement flexibility, control-lability, variable reduction ratio, reliability, and provision of ship's service power from the main bus. Several new technologies permit achievement of these objectives without weight, cost, and efficiency penalities. Four technology areas show promise of significantly increasing electric drive power density, including forced gas cooling, direct water cooling, permanent magnet exitation, and superconducting electromagnet excitation. Each of these technologies is examined to display the essential machine characteristics, the areas of technical risk, and the degree of anticipated weight and volume reduction for a typical application. System considerations for propulsion systems utilizing the various types of machine technologies are also discussed.

交流電機による実用的船舶推進方式改善の理論と実験

Electric ship propulsion systems have been rarely used since old times. However, it can be considered that feasible condition of such propulsion systems has been recently produced owing to various kinds of variation of situation. Six kinds of feasible ship propulsion systems using alternating current machines including author's methods are chosen under such condition in this paper.Conceptions, theories and the test results for continuous speed control of the following two kinds of author's methods of these propulsion systems are introduced.(1) combination of electromagnetic coupling with synchronous motor of which the system is accentuated in economy of fuel oil for ship propulsion.(2) combination of induction generator with synchronous motor of which the system is accentuated in free arrangement of propulsion prime mover.These methods can be considered superior to CPP methods in points of reliability, efficiency and cost.These methods can also be considered superior to other electric ship propulsion systems in points of reliability, efficiency and arrangement, thinking that such methods as use synchronous motors don't need mechanical gearings generally.On the other hand, improvement of constructions of electric machines as well as of systems in these two methods should be considered. Especially, it is important to make these electric machines brushless. Principles of these propulsion systems composed of brushless type electric machines and the results of the experiments confirming the right of the principles are explained in this paper.It could be well-ascertained from the above principles, theories and test results that these two methods are realizable.

A New Concept of Electric Ship Propulsion

Based on a principle established by Faraday in the nineteenth century, acyclic machines produce a true direct current. They are smaller, lighter in weight, and higher in efficiency than commutator-type dc motors and generators. By using the eutectic alloy of sodium and potassium as the current-carrying medium, acyclics eliminate the need for carbon brushes and the maintenance associated with them, thus leaving only the bearings and auxiliaries subject to normal maintenance. The authors point out the applicability of acyclics to ship propulsion by showing a schematic of the control system and listing the benefits of acyclic machinery for this application.

Parallel operation of two synchronous machines

The paper derives the equations required in the prediction of the steady-state characteristics of an alternator supplying a synchronous motor, which is of particular interest in electric ship propulsion. These equations are valid for any degree of saliency and any value of synchronous reactance in either machine. Since considerable labour is required in the numerical evaluation of the equations, the power, terminal voltage, armature current and pole angles at pull-out; as functions of the machine synchronous reactances, are given in the form of tables or families of curves. A curve is given showing the variation of the pull-out power with saliency, and another shows the extent to which the pull-out power of a combination of two machines is reduced in comparison with the values which would be obtained if either machine were running on an infinite busbar.

The medalist's career

The 1945 Lamme Medalist, David C. Prince, is first and foremost an inventer with 93 patents to his credit covering subjects ranging from electric ship propulsion to welding circuits. A consistent breaker of tradition, he is one of those who have the ability and imagination to think in terms of progress in broad steps regardless of the seeming insurmountability of the problems confronting them. He is considered an ideal choice for the medal which symbolizes the engineer's hopeful attitude toward the seemingly unattainable.

Electric Propulsion of Ships

IN a paper read to the North-East Coast Institution of Engineers and Shipbuilders at Newcastle-on-Tyne on December 16 by Mr. L. R. Home, the development of the electric propulsion of ships was traced over the last hundred years.

Diesel Electric Propulsion of Ships

Diesel Electric Propulsion of Ships

ELECTRIC PROPULSION OF SHIPS*

Journal of the American Society for Naval EngineersVolume 38, Issue 2 p. 346-453 ELECTRIC PROPULSION OF SHIPS* ESKIL BERG, ESKIL BERG GENERAL ELECTRIC COMPANYSearch for more papers by this author ESKIL BERG, ESKIL BERG GENERAL ELECTRIC COMPANYSearch for more papers by this author First published: May 1926 https://doi.org/10.1111/j.1559-3584.1926.tb05548.x * A paper presented to the North East Copst Institution of Eagincerr and Ship-builders, New Castle, England, February 12. 1926. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume38, Issue2May 1926Pages 346-453 RelatedInformation

Electric propulsion of ships

Electric propulsion of ships

Discussion at Spring convention: Electrical ship propulsion

Discussion at Spring convention: Electrical ship propulsion

Historical review of electrical applications on shipboard

During the year 1919, the Chairman of the Marine Committee of the Institute appointed a sub-committee with a view to compiling and recording data relative to the development and growth of electricity on shipboard. The instructions to the subcommittee included the preparation of a report, or historical review, which was to form the basis for a continuing record of such matters in the files of the Institute. After a careful investigation of the situation, the historical subcommittee found itself confronted with a task of no small proportions and one which would require, with the limited time available for such research work, probably several years to complete. An outline was prepared, however, of the ground which it was intended to cover and a preliminary report, submitted with the Marine Committee's report at the annual convention at White Sulphur Springs in 1920 and appears in the Institute's Transactions for that year. Continuing with the work for several years, the Historical Committee in April, 1923, submitted its report to the Marine Committee of the work and investigations which had been then made to date. This report of April 27, 1923 with its “Foreward” is given complete as rendered with such minor changes and corrections as shown by further investigations to be necessary. To this original report a brief section on “Electric Ship Propulsion” has been recently added. To complete this report to date, the sections on “Electrical Auxiliaries” and the appended list of references, are still to be added, although considerable work has already been done in connection therewith. Although it is regretted that the report is not complete in all details, the Marine Committee has felt that owing to the rapidly increasing interest in shipboard electrical installations that the time is opportune for the presentation of this information as at present compiled and with a view to completing the report at as early a date as practical. While we appreciate that this paper owing to its volume, will be read in the abstract only by those casually interested, to those who are interested in the subject, we trust the information will prove of considerable value. As information of this character has its greatest value as a historical record, we trust the Institute may be able to take steps to preserve the same in a substantial and conveniently accessible form in its files.

Electric Propulsion of Ships

This paper deals with the electric propulsion of practically all classes of vessels. The several types of electric drive are treated, in general, with special emphasis on Diesel-electric drive, as it is believed that this type of electric drive will be of most general interest, particularly to the inland section of our country, since it is especially applicable to the smaller size vessels, such as are used on rivers and lakes, to vessels in the coastwise trade and to the usual size of ocean freighter. All types of propelling equipment, however, will be referred to for the purpose of comparing the advantages of electric drive with other methods of ship propulsion and to show the natural advantages of each particular system. It is the intent of this paper to provide data valuable in the selection of the proper type of drive for each application, which must necessarily be determined by the character of the vessel and the service it is to render. Each type referred to has a particular field in which it is best suited. The authors desire to give credit to the Westinghouse and General Electric Companies for much of the data and material for cuts included in this paper.