CONTENTS • xi
Induction Motor with Commutator
PAGE
58. Wave shape of commutated full frequency current in induction
• motor secondary—Its low frequency component—Full fre-
quency reactance for rotor winding—The two independent .
variables: voltage and phase—Speed control and power factor
correction, depending on brush position..........89
59. Squirrel cage winding combined with commutated winding—
Heyland motor—Available only for power factor control—Its
limitation.......................91
CHAPTER V. SINGLE-PHASE INDUCTION MOTOR.
60. Quadrature magnetic flux of single-phase induction motor pro-
duced by armature currents—The torque produced by it—
The exciting ampere-turns and their change between synchron-
ism and standstill....................93
61. Relations between constants per circuit, and constants of the
total polyphase motor—Relation thereto of the constants of
the motor on single-phase supply—Derivation of the single-
phase motor constants from those of the motor as three-phase or
quarter-phase motor...................94
62. Calculation of performance curves of single-phase induction
motor—Torque and power...............96
63. The different methods of starting single-phase induction motors
—Phase splitting devices; inductive devices; monocyclic de-
vices; phase converter................. 96
64. Equations of the starting torque, starting torque ratio, volt-
ampere ratio and apparent starting torque efficiency of the
single-phase induction motor starting device........98
65. The constants of the single-phase induction motor with starting
device.........................100
66. The effective starting impedance of the single-phase induction
motor—Its approximation—Numerical instance......101
67. Phase splitting devices—Series impedances with parallel con-
nections of the two circuits of a quarter-phase? motor—-Equa-
tions .........................101$
68. Numerical instance of resistance in one motor circuit, with
motor of high and of low resistance armature.......104
69. Capacity and inductance as starting device-—Calculation of
values to give true quarter-phase relation.........100
70. Numerical instance, applied to motor of low, and of higli arma-
ture resistance.....................108
71. Series connection of motor circuits with shunted impedance-—
Equations, calculations of conditions of maximum torque
ratio—Numerical instance................109
72. Inductive devices—External inductive devices—Internal in-
ductive devices....................Ill
73. Shading coil—Calculations of voltage ratio and phase angle . 112