RU2095916C1 - Ventilation system for electric motor - Google Patents

Abstract

FIELD: electric engineering. SUBSTANCE: device has core of stator 1 with winding 2, which radial ventilation channels are separated in tangential direction into regions 3 for inlet of cooling gas into space 4 and regions 5 for outlet of cooling gas from space 4. Inner bores in core of stator 1 hold non-magnetic housing 7 by means of spacing insertions 6 between which channels are provided for transmission of gas from regions 3 to regions 5. Channels 8 are spaced from rotor 9 by means of housing 7. EFFECT: improved heat condition of active members of stator of electric motor. 2 dwg

Description

 The invention relates to electrical engineering, and in particular to cooling systems of electrical machines, mainly turbogenerators.

A multi-jet ventilation system of an electric machine is known, in which the stator core with radial ventilation channels has longitudinal sectioning into cooling gas inlet zones into the gap and gas discharge zones from the gap [1]
Also known is the radial tangential ventilation system of an electric machine, in which the radial channels of the stator core are tangentially divided into cooling gas inlet zones into the gap and gas discharge zones from the gap. This ventilation system is adopted as a prototype of the invention [2]
Both ventilation systems have the disadvantage that the radial ventilation ducts of the stator core, through which the gas is discharged from the gap, are fed by gas heated in the gap by mechanical losses and losses in the rotor, as a result of which the temperature of the active parts of the stator increases.

 The aim of the invention is to reduce the temperature of the active parts of the stator of an electric machine.

 This goal is achieved due to the fact that in the ventilation system of an electric machine containing a stator core, equipped with an internal bore with a rotor installed in it with a gap, radial ventilation channels divided into zones for supplying cooling gas to the gap and zones for gas removal from the gap, on the inside A non-magnetic shell with remote inserts is fixed to the stator core bore, between which there are channels for the flow of cooling gas from one zone to another, separated from the rotor of the indicated shell Chkoy.

 Due to the fact that the shell separates the gas circulating in the stator core from the gas heated in the gap by mechanical losses and losses in the rotor, it is possible to lower the temperature of the active parts of the stator.

 Figure 1 shows a cross section of a turbogenerator, with radial tangential gas circulation in the stator core; figure 2 is a longitudinal section of a turbogenerator, with a multi-jet gas circulation system in the stator core.

 The invention is illustrated by the example of two versions of the ventilation system of an electric machine, namely a turbogenerator, differing from each other in the direction of sectioning of the radial channels of the stator core. According to the first embodiment (Fig. 1), the ventilation system of the electric machine contains a stator core 1 with a winding 2, the radial ventilation channels of which are tangentially divided into zones 3 of the cooling gas inlet into the gap 4 and gas discharge zones 5 from the gap 4. On the inner core bore the stator 1 with the help of the remote inserts 6, a non-magnetic shell 7 is fixed. Between the remote inserts 6 there are channels 8 for gas flow from zones 3 to zones 5, and the channels 6 are separated from the rotor 9 by the shell 7. In the space between ribs II oriented along the longitudinal axis of the machine are installed on the stator head 1 and body 10, between which chambers 12 are formed for supplying cold gas to zones 3 and chambers 13 for releasing hot gas from zones 5.

 The second embodiment of the ventilation system of the electric machine (Fig. 2) is similar to the first version and differs from it in that the stator core is partitioned 1 into zones 3 of the cooling gas inlet into the gap 4 and the gas discharge zone 5 from the gap 4 is made in the longitudinal direction, accordingly, the ribs 11, by means of which chambers 12 for supplying cold gas to zones 3 and chambers 13 for releasing hot gas from zones 5 are formed, oriented perpendicular to the longitudinal axis of the machine.

 We consider the operation of the ventilation system of an electric machine using an example of the first design (Fig. 1). Under the pressure of the venting elements (not shown), the cooling gas through the chambers 12 enters zones 3 and then, moving in the tangential direction through the channels 8, flows into zones 5, from where it returns to the ventilating elements through the chambers 13 (in Fig. 1, the gas movement is indicated by arrows ) Due to the shell 7, the gas circulating in the channels 8 is not mixed with the gas washing the rotor 9, and is not heated by the mechanical losses and losses in the rotor that arise in the gap; as a result, the temperature of the winding 2 and the stator core 1 decreases.

 The greatest technical and economic efficiency of the proposed technical solution, consisting in increasing the ultimate unit power of an electric machine, is achieved by using an air cooling medium, since the worse heat dissipating properties of air in comparison with hydrogen complicate the problem of removing heat losses from the active parts of the stator.

Claims (1)

 The ventilation system of an electric machine containing a stator core, equipped with an internal bore with a rotor installed in it with a gap, radial ventilation channels divided into cooling gas supply zones into the gap and gas removal zones from the gap, characterized in that non-magnetic is fixed to the inner bore of the stator core a shell with remote inserts, between which there are channels for the flow of cooling gas from one zone to another, separated from the rotor by the specified shell.

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