Electrical generator or motor structure – Dynamoelectric – Rotary
Patent
1999-07-27
2000-10-10
Ponomarenko, Nick
Electrical generator or motor structure
Dynamoelectric
Rotary
310 45, 310215, H02K 334, H02K 340
Patent
active
061304964
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a stator coil for an electric rotating machine which is manufactured by a global impregnation method with which a stator coil accommodated in a slot of stator core is impregnated with resin which is then cured.
BACKGROUND ART
In general, methods of manufacturing a stator coil for an electric rotating machine are sorted as a individual impregnation method and a global impregnation method. The individual impregnation method includes the steps of impregnating only a stator coil; heating and curing the resin in a heated press; and joining the stator coil with a slot of stator core; and winding wire. The global impregnation method includes the steps of joining a stator coil, which is not impregnated with the resin, to a slot of stator core; winding wire; and impregnating with the resin which is then cured. The global impregnation method causes the stator coil and the stator core to be strongly secured to each other. Therefore, the overall body of the winding has great mechanical rigidity, causing the thermal resistance between the stator coil and the stator core to be reduced as compared with that realized with the individual impregnation method. As a result, a rise in the temperature of the stator coil caused from heat produced from a conductor within stator coil during the operation can efficiently be prevented as compared with the individual impregnation method. If the stator coil is manufactured by the global impregnation method, an advantage can be realized in that the manufacturing process can be shortened because only one execution of each of the impregnation and curing processes is required.
On the other hand, size reduction and large capacity of the electric rotating machine, which is manufactured by the global impregnation method, have caused the current density of the conductor of the stator coil to be raised. Thus, the heating value of the conductor within stator coil is increased. In general, when an electric rotating machine rotates, heat generated in the conductor within stator coil serving as a driving force causes shearing stress to occur between the surface of the stator coil and the slot of stator core owing to the difference in the coefficients of thermal expansion. Therefore, the heating of the conductor within stator coil is increased, causing the shearing force to be enlarged. Thus, there arises a problem in that defects, such as separation and cracks, occur in ground wall insulation of stator coil.
On the other hand, as a method for shear stress relaxation occurring in the ground wall insulation of a stator coil, a contrivance has been disclosed by the applicant of the present invention in Japanese Patent Application No. 8-120222, in which an non-adhesive tape is wound around the outer surface of the ground wall insulation of the stator coil.
FIG. 9 is a diagram showing the conventional stator coil, in which an outlet portion of the slot is illustrated, which is included in a structure in which the stator coil is employed in a high-voltage electric rotating machine. Referring to the drawing, reference numeral 1 represents a stator core, 13 represents a stator coil, 13a represents an upper coil, 13b represents a lower coil, 3 represents a conductor within the stator coil, 4 represents a ground wall insulation of the stator coil, 5 represents a wedge, 6 represents an insulating spacer between upper and lower coil, 7 represents a slot of stator core, 8 represents a conductive-and-non-adhesive tape, and 9 represents a semiconductive tape.
FIG. 10 is a diagram showing a portion of the conductive-and-non-adhesive tape 8 in the lengthwise direction. One of the surfaces of the conductive-and-non-adhesive tape 8 is subjected to a surface treatment by corona discharge. FIG. 11 is a diagram showing a state of accommodation in which the conventional stator coil has been accommodated in the slot of stator core 7.
That is, a mica tape is wound around the conductor 3 within stator coil several times so that the insulating layer 4 of the stator coil i
REFERENCES:
patent: 3679925 (1972-07-01), Fort
patent: 4533580 (1985-08-01), Otty
patent: 4760296 (1988-07-01), Johnston et al.
patent: 5030870 (1991-07-01), Wichmann
patent: 5066881 (1991-11-01), Elton et al.
patent: 5319276 (1994-06-01), Schuler
patent: 5574325 (1996-11-01), Musil et al.
Bitou Wataru
Shiota Hiroki
Takada Shiro
Takigawa Hideki
Tsukiji Makoto
Mitsubishi Denki & Kabushiki Kaisha
Nguyen Tran N
Ponomarenko Nick
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