RU2309512C1 - Method for cooling an electric machine and an electric machine - Google Patents

Abstract

FIELD: electric engineering and electric mechanical engineering, namely - systems for cooling electric machines, primarily turbo-generators, with closed ventilation cycle.

SUBSTANCE: in accordance to the invention, electric machine includes body (1), comprising coolers (5), (6) of stator (2) and rotor (4), stator (2), having radial channels (11) in end zones of core, rotor (4), installed in stator (2) with air gap and having ventilation channels (13) with inputs and outputs on different rotation radiuses, ventilators (7), positioned on both sides of rotor barrel, and chambers (8), (9), one of which, chamber (8) for collecting cold air, is positioned between coolers (5) of stator and external surface of stator core (2), and another one, chamber (9) for collecting heated air, is positioned in placement zones of frontal parts of winding (10) of stator (2), outputs of stator coolers (5) and inputs into radial channels (11) of end zones of stator core are connected to chamber (8) for collecting cold air, and outputs of radial channels (11) of end zones, inputs of rotor coolers (6), inputs into ventilators (7) and outputs of rotor channels are connected to chamber (9) for collecting heated air, while outputs of coolers (6) of rotor (4) are connected to inputs of rotor channels, and high pressure zone (14) of ventilators (7) is connected to stator coolers inputs. In accordance to the invention, press plates have channels (12), inputs of which are connected to chamber (8) for collecting cold air, and outputs are connected to chamber (9) for collecting hot air, and main zone of stator core has water cooling system in form of coolers, positioned between packets (3) of stator core. Method for cooling the electric machine characterized above is realized as follows. Cooling air from stator coolers through the chamber for collecting cold air of stator, set up between stator coolers and external surface of stator core, and from rotor coolers, is directed by means of forcing elements, namely ventilators, positioned on both sides of rotor barrels, and rotor channels, along various routes into channels of rotor and stator core, and the air heated up in these channels is directed into chamber for collecting heated air, set up in zones of placement of frontal parts of stator winding, to inputs of rotor coolers and to inputs of ventilators and further - to stator coolers, where one route is set up from stator coolers, from outputs of which cooling air is directed from external surface of stator core into radial channels of end zone of stator core, another route is set up from rotor coolers, from outputs of which cooling air is directed into rotor channels. One more route, in accordance to the invention, is set up starting at rotor coolers, from outputs of which cooling air is directed into channels of press plates of stator core, while cooling of stator winding and main stator core is performed by water, circulating in pipes of coolers, which are positioned between main stator core packets.

EFFECT: increased cooling efficiency of stator winding and core, reduced material consumption of high power electric machines.

2 cl, 1 dwg

Description

The claimed group of inventions relates to electrical engineering, and in particular to cooling systems of electrical machines, mainly turbogenerators, with a closed ventilation cycle.

The known cooling system of an electric machine, described in the article "A series of turbogenerators with full water cooling," by I.A. Kadi-Ogly, Yu.F. Antonov, VB Bragin and others (Collection "Electrosila" No. 39, 2000 g.). With such a cooling system, the stator, rotor windings and active steel of the stator core are cooled directly with water. Water cooling of the stator and rotor windings is carried out using hollow copper conductors through which the distillate circulates, and water cooling of the stator core is carried out using flat silumin coolers located between the stator core packages.

Such a scheme is effective from the point of view of cooling, but requires expensive equipment for the preparation, cooling and circulation of distillate in the stator and rotor windings.

A known electric machine with combined cooling (RF Patent No. 2226027, Н02К 9/16, Н02К 9/06, published March 20, 2004), in which the core along its entire length, including end zones, is equipped with its own water cooling system in the form of flat cooling elements located between the core packages, and the air cooling of the rotor winding and the frontal parts of the stator winding is made according to an exhaust circuit, in which two fans located on both sides of the rotor barrel and rotor ventilation ducts are used as pressure elements s and outputs of which are located at different radii of rotation of the rotor. In this electric machine, the cooling air supply zone after the coolers is organized in the area of the frontal parts of the stator winding and in the ventilation ducts of the rotor, and the area for removing heated air from the frontal parts of the stator winding and the air gap between the stator and rotor is combined with the exhaust zone of the fan.

Air cooling with such a system is as follows.

The cooling air through the fans is fed to the coolers. From the chamber after the coolers, the cooling air is sent in two ways to cool the frontal parts of the stator winding and into the rotor channels.

The first flow of cooling air is directed to the area of the frontal parts of the stator winding.

A second stream of cooling air is fed into the ventilation ducts of the rotor, after which it enters the air gap between the stator and the rotor.

From the air gap between the stator and the rotor and the frontal parts of the stator winding, the heated air enters the exhaust zone of the fan and is directed to the coolers.

The disadvantage of the proposed cooling system is the sequential inclusion of a fan in the cooling circuit of a self-ventilated rotor with radial channels, the inputs and outputs of which are located at different radii of rotation. A fan is not required to cool a self-venting rotor. The successive inclusion of a fan in the rotor cooling circuit leads to an increase in ventilation losses and a decrease in efficiency electric car.

The closest in technical essence to the claimed invention is a method of gas cooling of an electric machine and an electric machine described in the invention according to the patent of the Russian Federation 2258295 (RF Patent No. 2258295, Н02К 9/06, Н02К 9/16, Н02К 9/18, publ. 10.08. 2005 Bull. No. 22).

In the known method of cooling an electric machine with a closed exhaust ventilation cycle, the cooling gas from the stator and rotor coolers is directed through fans located on both sides of the rotor barrel and rotor channels with inputs and outputs located at different radii of rotation of the rotor, in three parallel ways into the rotor channels and channels of the stator core, and the gas heated in these channels is directed to the stator and rotor coolers through the heated gas collection chamber, organized in the areas of the frontal part stator winding.

The first path of the cooling gas is arranged from the stator coolers through the cold gas collection chamber located between the stator coolers and the outer surface of the stator core, to the entrances to the channels of the main zone of the stator core, from which heated gas is collected through gas collection ducts from the outside of the stator core and fed into the chamber collection of heated gas, organized in the areas of the frontal parts of the stator winding.

The second gas path is also arranged from the stator coolers through the stator cold gas collection chamber. In this case, cooling gas is supplied to the inlets into the radial channels of the end zone of the stator core, from which the heated gas is sent directly to the heated gas collection chamber.

The third gas path is arranged from rotor coolers, from the outlets of which cooling gas is sent to the rotor channels, and the gas heated in the rotor channels through the air gap between the rotor and the stator is also fed to the heated gas collection chamber.

From the heated gas collection chamber, part of the gas is directed to rotor coolers, and its other part to the fans and further to the stator coolers.

An electric machine that allows this cooling method to be implemented includes a housing with stator and rotor coolers located in it, a stator having channels, the input and output of which are organized on the outer surface of the core, and radial channels in the end zones, the rotor installed in the stator with air gap, and having channels with inputs and outputs at different radii of rotation of the rotor, fans located on both sides of the barrel of the rotor, and chambers, the first of which is placed between the coolers and the outer surface new stator, and the second in the areas of the frontal parts of the stator winding. The outputs of the stator coolers are combined with the first chamber, in which on the outer surface of the stator core there are entrances to the channels of the main stator core and radial channels of the end zones, while the exits from these channels, the inputs of the rotor coolers and fans are connected to the second chamber. The outputs of the rotor coolers are connected to the entrances to the rotor channels, the exits from which communicate with the second chamber through the air gap between the stator and the rotor. The high pressure zone of the fans is connected to the inputs of the stator coolers.

In the known method of cooling an electric machine, the stator winding is cooled indirectly by gas circulating in the channels located between the stator core packets. For high power turbo generators, complete air cooling becomes ineffective.

The problem solved by the claimed group of inventions is to increase the cooling efficiency of the stator winding and core and reduce the material consumption of high-power electric machines.

This problem is solved due to the fact that in the claimed method of cooling an electric machine, the main stator core is equipped with its own water cooling system in the form of flat coolers, and air cooling of the end zones, the pressure plates of the stator core, the frontal parts of the stator winding and rotor is carried out according to an exhaust ventilation circuit, in which cooling air from the stator coolers through the cold air collection chamber, organized between the stator coolers and the outer surface of the stator core, and about tons of rotor coolers are directed through fans located on both sides of the rotor barrel, and rotor channels with inputs and outputs located at different radii of rotation of the rotor, in different ways to the rotor channels, radial channels of the end zones and to the channels of the pressure plates of the stator core, and heated in In these channels, the gas is directed to the coolers of the stator and rotor through the heated gas collection chamber, which is organized in the areas where the frontal parts of the stator winding are located.

One way of cooling air is arranged from the stator coolers through the cold air collection chamber located between the stator coolers and the outer surface of the stator core, to the entrances to the radial channels of the end zones of the stator core, from which heated air is supplied to the heated air collection chamber, organized in the frontal zones parts of the stator winding.

Another way of cooling air is provided from rotor coolers, from the outlets of which cooling air is sent to the rotor channels, and the air heated in the rotor channels through the air gap between the rotor and the stator is also fed to the heated air collection chamber.

Another way of cooling air is arranged from the stator coolers through the cold air collection chamber to the channels of the pressure plates of the stator core, from which the heated air is sent directly to the heated air collection chamber.

From the collection chamber of the heated air, part of the air is directed to the entrances of the rotor coolers, and the other part to the fan inlets and then to the stator cooler inputs.

Indirect water cooling of the stator winding and core is carried out using flat silumin coolers, which are located between the packages of the main stator core.

New in the claimed method is:

- supply of cooling air from the stator coolers through the cold air collection chamber located between the stator coolers and the outer surface of the stator core, into the channels of the pressure plates of the stator core, from which the heated air is sent directly to the heated air collection chamber,

- cooling of the stator winding and core (with the exception of end zones and pressure plates) using water circulating in the tubes of flat coolers placed between the packages of the main stator core.

An electric machine that allows the implementation of this cooling method includes:

- housing

- stator and rotor coolers,

- a stator having radial channels in the end zones of the core,

- pressure plates of the stator core having channels for the passage of cooling air,

- the main stator core, equipped with its own water cooling system in the form of flat coolers located between the packages of the stator core,

- a rotor mounted in a stator with an air gap and having channels with inputs and outputs at different radii of rotation of the rotor,

- centrifugal fans placed on both sides of the rotor barrel,

a cold air collection chamber located between the stator coolers and the outer surface of the stator core,

- a chamber for collecting heated air, located in the areas of the frontal parts of the stator winding.

The outputs of the stator coolers, the entrances to the radial channels of the end zones of the stator core, the entrances to the channels of the pressure plates communicate with the cold air collection chamber.

The outputs from the radial channels of the end zones and the channels of the pressure plates of the stator core communicate with the heated air collection chamber.

The outputs of the rotor coolers communicate with the entrances to the rotor channels, the exits from which through the air gap between the stator and the rotor communicate with the heated air collection chamber.

The heated air collection chamber is connected directly to the rotor cooler inlets and the fan inlets, and it communicates with the stator cooler inlets through the high pressure zone of the fans.

New in the claimed device is:

- organization of cooling of pressure plates using channels for air passage;

- combining the entrances to the channels of the pressure plates of the stator core with the cold air collection chamber;

- connection of the heated air collection chamber to the exits from the channels of the pressure plates of the stator core;

- placement between the packages of the main stator core of flat water coolers.

The sign "placement between the packages of the main stator core of flat water coolers" is known from RF patent No. 2226027 and from the article "Series of turbo-generators with full water cooling" published in the collection "Electrosila" No. 39, but in the inventive electric machine flat silumin coolers are placed only between packages of the main stator core, and the end zones and pressure plates of the stator core are cooled by air.

To solve the problem posed in the present invention, it is possible only when using all of the features listed in the formula together.

The method of cooling an electric machine and an electric machine in which the main stator core is equipped with a water cooling system, and the air cooling of the rotor, the frontal parts of the stator winding, end zones and pressure plates of the stator core is carried out by cooling air through a closed exhaust ventilation cycle, under the action of the pressure developed by the channels rotor, and centrifugal fans, not identified in the existing level of technology, which allows us to conclude that the claimed technical solution to the condition atentosposobnosti "inventive step".

The proposed technical solution is illustrated by the drawing, which shows an electric machine in which such combined cooling is used.

The electric machine includes a housing 1, a stator 2 placed therein, having a core with packets 3, a rotor 4 mounted in the stator 2 with an air gap, coolers 5 of the stator 2, coolers 6 of the rotor 4, fans 7 and chambers 8 and 9.

Chamber 8 — a chamber for collecting cold air — is located between the coolers 5 of the stator 2 and the outer surface of the core of the stator 2, and chamber 9 is a chamber for collecting the heated air in the areas of the frontal parts of the winding 10 of the stator 2.

The stator core 2 has radial channels 11 in the end zones, and the pressure plates of the stator core 2 have channels 12 for the passage of cooling air.

The rotor 4 has ventilation channels 13 with inputs and outputs at different radii of rotation of the barrel of the rotor 4.

The outputs of the coolers 5 of the stator 2 are in communication with the chamber 8, in which the entrances to the radial channels 11 of the end zones and to the channels 12 of the pressure plates of the stator 2 are located.

The outputs from the radial channels 11 of the end zones and the channels 12 of the pressure plates communicate directly with the camera 9, located in the area of the frontal parts of the winding 10 of the stator 2.

The outputs of the coolers 6 of the rotor 4 through the space located between the housing 1 and the high pressure zone 14 of the fans 7 are connected with the inputs to the ventilation channels 13 of the rotor 4, the outputs from the ventilation channels 13 of the rotor 4 through the air gap between the stator 2 and the rotor 4 communicate with the camera 9 .

The chamber 9 communicates with the inputs of the coolers 6 of the rotor 4 and the inputs of the centrifugal fans 7.

The stator core 2 has its own water cooling system in the form of flat coolers located between the packages 3 of the stator core 2 and made in the form of segments with coils filled in them from a stainless steel tube for water circulation.

The inventive method is as follows.

The first flow of cooling air from the outputs of the coolers 5 of the stator 2 through the chamber 8 is sent to the channels 12 of the pressure plates of the core of the stator 2.

The second flow of cooling air from the outputs of the coolers 5 of the stator 2 through the chamber 8 is fed into the radial channels 11 of the end zone of the core of the stator 2.

Heated air from the radial channels 11 of the end zones and channels 12 of the pressure plates of the core of the stator 2 is sent to the chamber 9.

The third flow of cooling air from the outputs of the coolers 6 of the rotor 4 is fed into the ventilation channels 13 of the rotor 4, and from the ventilation channels 13 through the air gap between the stator 2 and the rotor 4, the heated air enters the chamber 9.

From the chamber 9, the heated air is directed to the inputs of the coolers 6 of the rotor 4 and to the inputs of the fans 7. Through the high pressure zones 14 of the fans 7, the heated air is supplied to the inputs of the coolers 5 of the stator 2.

Cooling water circulates through the coils of the stainless steel tube, which are located in the coolers between the packages 3 of the core of the stator 2.

The specified technical solution is carried out industrially, which allows us to conclude that the claimed group of inventions meets the patentability condition "industrial applicability".

Claims (2)

1. The method of cooling an electric machine, in which cooling air from the stator coolers through the stator cold air collection chamber, organized between the stator coolers and the outer surface of the stator core, and from the rotor coolers is directed by pressure elements, namely fans, located on both sides of the rotor barrel and the rotor channels in different ways to the channels of the rotor and the stator core, and the air heated in these channels is directed through the heated air collection chamber, organized in zones p the positioning of the frontal parts of the stator winding, to the rotor cooler inputs and to the fan inputs, and then to the stator coolers, while one way is organized from the stator coolers, from the outputs of which cooling air is directed from the outer surface of the stator core to the radial channels of the end zone of the stator core, another way is organized from rotor coolers, from the outputs of which cooling air is directed into the rotor channels, characterized in that another way is organized from stator coolers, from whose outputs the cooler ayuschy air is directed into the channels of push plates of the stator core, the cooling of the stator winding and the stator core of the core is carried out with water circulating in the cooler tubes which are disposed between the main stator core packets. 2. An electric machine, including a housing, stator and rotor coolers located in it, a stator having radial channels in the end zones of the core, a rotor installed in the stator with an air gap and having channels with inputs and outputs at different radii of rotation, fans placed with both sides of the rotor barrel and the chamber, one of which, the cold air collection chamber, is located between the stator coolers and the outer surface of the stator core, and the other, the heated air collection chamber, is located in the areas of the frontal part stator windings, the outputs of the stator coolers and the entrances to the radial channels of the end zones of the stator core communicate with the cold air collection chamber, and the exits from the radial channels of the end zones, the rotor cooler inputs, the fan inlets and the rotor channel outlets communicate with the heated air collection chamber, the outputs of the rotor coolers communicate with the entrances to the rotor channels, and the high-pressure zone of the fans communicates with the inputs of the stator coolers, characterized in that the pressure plates have channels, the inputs of which are connected ayutsya collection chamber with cold air, and the outputs of which are communicated with a collection chamber pre-heated air, and the main area of the stator core has a water cooling system in the form of coolers disposed between the stator core packets.