## Power apparatus and electric machines

### More general concepts than this:

### More specific concepts than this:

- Sort by:
- Newest first
- Titles A to Z

### Filter by subject:

- Electrical and electronic engineering [15]
- Power systems and applications [15]
- Power apparatus and electric machines [15]

### Filter by content type:

### Filter by publication date:

- 1922 [15]

### Filter by author:

- L.H.A. Carr [5]
- S.P. Smith [4]
- F.P. Whitaker [3]
- W. Cramp [3]
- W.E. Burnand [3]
- A.B. MacLean [2]
- A.E. McColl [2]
- A.M. Taylor [2]
- A.P. Robertson [2]
- A.T. Robertson [2]
- F.H. Downie [2]
- F.J. Teago [2]
- G.A. Juhlin [2]
- J.K. Catterson-Smith [2]
- M.L. Kahn [2]
- R. Townend [2]
- R.A. Chattock [2]
- R.G. Jakeman [2]
- W.B. Woodhouse [2]
- A. Hay [1]
- A.B. Mallinson [1]
- A.C. Stewart [1]
- A.S. Hampton [1]
- B. Hague [1]
- B.C. Battye [1]
- C. Rettie [1]
- C. Rettle [1]
- C. Sykes [1]
- C.C. Atchison [1]
- C.S. Buyers [1]
- C.T. Allan [1]
- C.W. Marshall [1]
- D. Robertson [1]
- D. Weir [1]
- D.H. Bishop [1]
- D.I. Dawbarn [1]
- D.M. Buist [1]
- D.S. Baddeley [1]
- D.S. Paxton [1]
- E. Fawssett [1]
- E. Wilson [1]
- E.I. David [1]
- E.M. Johnson [1]
- E.P. Hill [1]
- E.W. Ashby [1]
- E.W. Marchant [1]
- E.W. Young [1]
- F. Creedy [1]
- F. Forrest [1]
- F.J. Moffett [1]
- F.S. Adkins [1]
- F.T. Chapman [1]
- F.W. Carter [1]
- G. Austin [1]
- G. Henderson [1]
- G. Kapp [1]
- G. Wüthrich [1]
- G.F. Sills [1]
- G.G. Braid [1]
- G.M.S. Sichel [1]
- H. Brentano-Hintermann [1]
- H. Burge [1]
- H.A. McGuffle [1]
- H.B. Poynder [1]
- H.E. O'Brien [1]
- H.H. Wright [1]
- H.M. Sayers [1]
- H.W. Clothier [1]
- J. Anderson [1]
- J. Frith [1]
- J. Rosen [1]
- J.C.B. Ingleby [1]
- J.F. Nielson [1]
- J.H. Johnson [1]
- J.M. Donaldson [1]
- J.M. Heslop [1]
- J.R. Beard [1]
- J.R. Cowie [1]
- J.S. Peck [1]
- J.W.A. Abernethy [1]
- Ll.B. Atkinson [1]
- P. Hunter-Brown [1]
- P.J. Plevin [1]
- P.R. Wray [1]
- Philip Dawson [1]
- R. Orsettich [1]
- R.C. Atkinson [1]
- R.D. Archibald [1]
- R.G. Kilburne [1]
- R.J.H. Beaty [1]
- R.M. Longman [1]
- R.T. Smith [1]
- S. Neville [1]
- S.C. Bartholomew [1]
- S.E. Hall [1]
- T. Baxendale [1]
- T. Carter [1]
- V. Mallalieu [1]
- W. Browning [1]
- W. Holttum [1]
- See more See less

### Filter by access type:

(1) A suggestion is made that the high-pitched notes emitted by some induction motors are due to a side-pull arising from an unsymmetrical field which may be produced when certain numbers of rotor slots are used.(2) A simple case is first considered and the dissymmetry shown.(3) and (4) The forces produced are indicated and their effects considered.(5) The field is analysed and found to include pairs of components, such that in each pair the numbers of poles differ by two. The interferences between such pairs of fields produce the effects observed.(6) An elementary investigation is made which gives an expression for the frequency of the note produced.(7) Illustrative examples are considered.(8) The principle is extended.(9) A more general investigation is made.(10) A rule is developed for determining what numbers of rotor slots should be avoided.(11) Some experimental results are given.

In many problems the resultant of a number of equal and equally spaced vectors is required in terms of their simple scalar sum. This relation is usually expressed in the form of a ratio*f*(Θ) = sin Θ/*q* sin (Θ/*q*),where *q* is the number of vectors spaced over an angle 20.The vectors may be those of the electromotive or the magnetomotive force of the coils of an armature winding; the quantity *f*(Θ) is then called the distribution factor, and is of frequent occurrence in the theory and design of armature windings.The object of this paper is to discuss the principal mathematical properties of the distribution factor, and to give a complete series of curves exhibiting these properties in a form suitable for practical application.

Railway electrification in this country will require converting machinery capable of operating from high-tension alternating-current systems with frequencies of 25 to 50 periods per second and delivering direct current at 1,500 volts.For this class of service the rotary converter possesses many desirable characteristics, viz. ease and quickness of starting, high efficiency, high overload capacity, high power factor (especially on full load and overloads), freedom from limitation of high-tension a.c. voltage, reasonable flexibility of control of the d.c. voltage, reasonable freedom from harmonics in the alternating-current supply, and from undulations and ripples in the d.c. voltage delivered.The limiting conditions in design and operation of such equipments are discussed, more particularly the effect of frequency on the generation of direct current at 1500 volts, the effects of short-circuits and flash-overs, and the deviation of the d. c. voltage from a uniform value.

The subject-matter of this paper consists of the results of tests on a three-phase shunt commutator motor manufactured by the Swedish General Electric Company. There are three main divisions:—(*a*) The operation of the motor, as normally supplied by the manufacturers, with symmetrical brush-gear setting.(*b*) The operation of the motor with variable brush-gear setting.(*c*) That portion of the theory, with the vector diagrams, necessary for understanding the operation of the motor.

The induction-type synchronous motor is a polyphase motor and has a cylindrical rotor. It is started as an induction motor of the slip-ring type and synchronizes itself when direct current is switched into the rotor.The characteristics and construction of this type of motor are compared with those of other polyphase motors.The self-synchronizing feature of this type of machine is discussed in detail so as to present a full physical conception of the phenomena which occur, and the subject is illustrated by means of oscillograms.A mathematical expression is deduced for the limiting conditions beyond which synchronizing is uncertain.The considerations which determine the selection of the excitation voltage are discussed, as well as the method of control and other practical points affecting the installation of these machines.