KR101407947B1 - cooling system and method of generator based on ORC and generating equipment and method using them - Google Patents

Abstract

A generator cooling system according to the present invention includes a rotating shaft 11 connected to a turbine 20 and rotated together with a turbine 20, a rotor coupled to a center of the rotating shaft 11 to be rotatable with the rotating shaft 11 And a cylindrical stator 14 located at an outer radius of rotation of the rotor 12. The stator 14 has an outer circumferential surface 17 and an inner circumferential surface 16 penetrating therethrough, A cooling fluid inlet 32 for introducing a part of the working fluid taken out from the stage into the stator 14 as a cooling fluid and a cooling fluid inlet 32 extending from the outlet of the cooling fluid inlet 32 to the rear surface of the turbine 20, A cooling channel 33 for cooling the cooling fluid introduced into the stator 14 to perform cooling inside the housing and to provide a flow path to the rear surface of the turbine 20, And flows from the cooling passage 33 A turbine rear flow passage 35 is provided to flow the cooling fluid to the working fluid inlet 31 side by using the centrifugal force in accordance with the rotation of the turbine 20 to draw out a part of the working fluid at the pump outlet end, And the cooling fluid evaporated inside the housing is used as the working fluid of the turbine 20 again.

Description

TECHNICAL FIELD The present invention relates to a cooling system of an ORC-based generator, a method thereof, a power generation apparatus using the same and a method thereof,

The present invention relates to a cooling system of an ORC-based generator, a method thereof, and a power generating apparatus and method using the same. More particularly, the present invention relates to a cooling system of an ORC-based generator And a method of producing the same, and a power generation apparatus and method using the same.

Organic Rankine Cycle (ORC) is a Rankine Cycle that uses an organic medium as a working fluid and refers to a system that generates electricity by recovering a heat source in a relatively low temperature range (60 to 200 ° C).

5, the Organic Rankine Cycle (ORC) comprises a pump 1, an evaporator 2, a turbine 3, a condenser 4, It is composed of basic elements of. The evaporator 2 conveys heat to the working fluid to heat it to the temperature required for driving the turbine and the turbine 3 converts the thermal energy of the working fluid to mechanical energy and the condenser 4 supplies the working fluid from the turbine 3 And the pump 1 serves to pressurize the low-pressure working fluid from the condenser 4 up to the evaporation pressure.

On the other hand, in a high-speed turbine-based power generation apparatus, a large amount of heat is generated due to electric resistance due to generation of electromotive force and friction between components in a generator housing including a stator and a rotor. Such heat generation can cause deformation of the internal components of the generator, and on the other hand, it can increase the electric resistance inside the coil wound on the stator, thereby inviting reduction in power generation efficiency. Although it is possible to consider using a separate cooling fluid for cooling the inside of the generator, there is a problem that a complicated cooling channel must be separately provided.

Meanwhile, in order to avoid providing a separate cooling fluid, it may be considered to utilize a part of the working fluid as a cooling fluid. However, there is a problem that the turbine output is lowered due to a decrease in the flow rate of the working fluid flowing into the turbine.

In order to solve the above-described problems, the present invention has been developed to solve the above-mentioned problems, and it is an object of the present invention to provide a turbine, which is capable of extracting a part of a working fluid without using a separate cooling fluid, A cooling system of an ORC-based generator for preventing a decrease in turbine output by reusing it as a working fluid, a method for the same, and a power generating apparatus using the same and a method therefor.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, an ORC-based generator cooling system includes a rotary shaft connected to a turbine and rotated together with a turbine, a rotor coupled to the rotary shaft center, A cooling fluid inlet formed to penetrate the outer circumferential surface and the inner circumferential surface of the stator and introducing a part of the working fluid drawn out from the pump outlet end to the inside of the stator as a cooling fluid; A cooling passage extending from the outlet of the cooling fluid inlet to the rear surface of the turbine to provide a flow path through which the cooling fluid introduced into the stator can perform cooling inside the housing and flow to the rear surface of the turbine, And the cooling fluid flowing from the cooling channel is supplied to the turbine A turbine rear flow passage is provided which uses a centrifugal force in accordance with the rotation to flow to the working fluid inlet port to draw a part of the working fluid from the pump outlet end and use the cooling fluid as a cooling fluid, And is used as a fluid.

And a cooling fluid regulating valve connected to the inlet of the cooling fluid inlet for regulating a flow rate of the cooling fluid.

The cooling fluid regulating valve regulates the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling flow path leading to the working fluid inlet may become an overheated steam state.

Meanwhile, the cooling method of the ORC-based generator according to the present invention uses a part of the working fluid at the outlet of the pump as a cooling fluid inside the housing of the generator, uses the evaporated cooling fluid as the working fluid of the turbine after cooling A method of cooling an ORC-based generator, the method comprising the steps of: flowing a cooling fluid into the stator through a cooling fluid inlet formed through the outer and inner surfaces of the stator through the stator; cooling the cooling fluid from the outlet of the cooling fluid inlet to the back of the turbine The cooling fluid flowing into the stator through the flow path is evaporated while cooling the interior of the housing to flow to the rear surface of the turbine, a step of flowing the cooling fluid flowing from the cooling channel through the rear flow path of the turbine positioned on the rear surface of the turbine The cooling fluid is supplied to the working fluid inlet side And the cooling fluid introduced into the working fluid merges with the working fluid at the inlet end of the turbine.

A cooling fluid regulating valve connected to the cooling fluid inlet is provided to regulate the flow rate of the cooling fluid.

The cooling fluid regulating valve regulates the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling flow path leading to the working fluid inlet may be in an overheated steam state.

Meanwhile, the ORC-based power generation apparatus according to the present invention includes a rotating shaft connected to a turbine and rotated together with a turbine, a rotor coupled to the center of the rotating shaft to be rotatable together with the rotating shaft, and a cylindrical A cooling fluid inlet formed to penetrate the outer circumferential surface and the inner circumferential surface of the stator and introducing a part of the working fluid drawn out from the pump outlet end to the inside of the stator as a cooling fluid, A cooling flow path extending from the turbine to the rear surface of the turbine so that the cooling fluid introduced into the stator performs cooling inside the housing and can flow to the rear surface of the turbine, The cooling fluid flowing from the flow path is centrifugally driven by the rotation of the turbine A turbine rear flow passage for flowing the fluid to the fluid inlet side is used to draw out a part of the working fluid at the outlet end of the pump and is used as a cooling fluid and the cooling fluid evaporated inside the housing is used again as a working fluid of the turbine .

And a cooling fluid regulating valve connected to the inlet of the cooling fluid inlet for regulating a flow rate of the cooling fluid.

The cooling fluid regulating valve regulates the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling flow path leading to the working fluid inlet may be in an overheated steam state.

Further, the turbines are provided in pairs, each of which is connected to both ends of the rotating shaft, and the rear surfaces of the turbines are opposed to each other so as to mutually offset the axial loads according to the front and rear pressure differentials of the turbine, And the pair of turbines are formed so as to generate an axial load of the same magnitude.

Meanwhile, the ORC-based power generation method according to the present invention is based on ORC, which uses a part of the working fluid at the outlet end of the pump as a cooling fluid inside the housing of the generator and uses the evaporated cooling fluid as the working fluid of the turbine after cooling The method of generating electricity according to claim 1, wherein the cooling fluid is introduced into the stator through a cooling fluid inlet formed by penetrating the outer and inner surfaces of the stator, through a cooling passage extending from the outlet of the cooling fluid inlet to the rear surface of the turbine, The cooling fluid flowing into the stator is evaporated while cooling the interior of the housing to flow to the rear surface of the turbine, the cooling fluid introduced from the cooling channel through the turbine rear flow path located on the rear surface of the turbine, To the working fluid inlet side using the centrifugal force according to the rotation of the working fluid inlet And joining the cooling fluid introduced into the working fluid with the working fluid at the inlet end of the turbine.

A cooling fluid regulating valve connected to the cooling fluid inlet is provided to regulate the flow rate of the cooling fluid.

The cooling fluid regulating valve regulates the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling flow path leading to the working fluid inlet may be in an overheated steam state.

The present invention can simplify and lighten the apparatus by drawing a part of the working fluid at the pump outlet end without using any additional cooling fluid. Further, by drawing out the working fluid from the pump outlet end and using it as the cooling fluid, it is possible to secure a relatively low-temperature cooling fluid within the operating temperature range of the working fluid. Since it has a pressure similar to the pressure at the inlet of the turbine, it is not necessary to provide a separate pressurizing device for reusing it as a working fluid of the turbine. In addition, in the cooling process, the efficiency of the whole generator can be increased by heating the cooling fluid by utilizing the heat inside the generator and reusing it as a working fluid of the turbine, that is, by recovering and reusing the waste heat energy.

In an embodiment of the present invention, the turbine of the generator is provided in a pair so as to be opposed to both ends of the rotating shaft, so that the axial load according to the front and rear pressure differentials of the turbine can be structurally canceled. Therefore, it is possible to improve the durability of the generator, and it is possible to prevent a decrease in output or an efficiency deterioration due to friction and bearing damage due to excessive axial load.

1 is a cross-sectional view showing a main configuration of a generator cooling system and a power generation apparatus according to an embodiment of the present invention.
2 is a cross-sectional view illustrating a flow path of a cooling fluid according to an embodiment of the present invention.
3 is an exploded perspective view showing a stator according to an embodiment of the present invention.
4 is a conceptual diagram showing axial load generated by the front and rear pressure differences of the turbine.
Fig. 5 is a schematic view showing an example of an ORC, that is, an organic medium cycle, showing its configuration and operation.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In the following drawings, like reference numerals are used to denote like elements, and even if they are shown in different drawings, they are denoted by the same reference numerals whenever possible, A detailed description of known functions and configurations will be omitted.

1 is a transverse sectional view showing a main structure of a cooling system of an ORC-based generator according to the present invention.

1, a cooling system of an ORC-based generator according to the present invention includes a rotating shaft 11 connected to a turbine 20 and rotated together with a turbine 20, A rotor 12 coupled to the center of the rotary shaft 11 and a cylindrical stator 14 located at an outer radius of rotation of the rotor 12.

The stator 14 has an outer circumferential surface 17 and an inner circumferential surface 16 penetrating therethrough and a part of the working fluid drawn out from the pump outlet end is introduced into the stator 14 as a cooling fluid. (32).

The cooling fluid introduced into the stator 14 from the outlet of the cooling fluid inlet 32 to the rear surface of the turbine 20 performs cooling inside the housing and flows to the rear surface of the turbine 20 A cooling flow path 33 is provided to provide a flow path that can be formed.

The turbine 20 is disposed at a rear surface of the turbine 20 and uses a centrifugal force generated by the rotation of the turbine 20 to flow the cooling fluid introduced from the cooling passage 33 toward the working fluid inlet 31, 35 are provided.

As a result, a part of the working fluid at the outlet end of the pump is withdrawn and used as a cooling fluid, and the cooling fluid evaporated inside the housing is utilized as the working fluid of the turbine 20 again.

The reason for withdrawing the working fluid from the pump outlet end is that the working fluid flowing into the inlet of the turbine 20 through the evaporator is pressurized to a very high pressure so that a pump having theoretically the same pressure The working fluid at the outlet end is drawn out. In addition, since the pump outlet end has a relatively low temperature in the Rankine cycle, efficient cooling can be performed by drawing out a small flow rate.

Although the cooling fluid inlet 32 is shown as two circular through holes in FIG. 3, the cooling fluid inlet 32 may be provided in various numbers as needed, and may be formed in various shapes such as a polygonal shape.

The liquid cooling fluid introduced into the stator 14 through the cooling fluid inlet 32 passes through the cooling channel 33 including the space between the stator 14 and the rotor 12 to perform cooling At the same time, the waste heat inside the housing is absorbed and evaporated. Thereafter, the cooling fluid flows into the rear center portion of the turbine 20, flows to the outer surface of the rear surface of the turbine 20, and finally is transferred to the working fluid inlet 31 to join with the working fluid. The cooling fluid introduced into the working fluid inlet (31) mixes with the working fluid and is expanded in the turbine (20).

The terms cooling fluid and working fluid as used herein refer to the same fluid in which only the terms are defined differently in order to highlight functional aspects. That is, a part of the working fluid is used as the cooling fluid. More particularly, in a typical Rankine cycle, a portion of the working fluid at the outlet end of the pump is withdrawn and used as a cooling fluid, and the refluxing heated fluid is mixed with the working fluid heated in the evaporator, (20) to perform expansion.

Preferably, the cooling fluid control valve 34 is connected to the cooling fluid inlet 32 to control the flow rate of the cooling fluid. The cooling fluid regulating valve 34 regulates the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling channel 33 leading to the working fluid inlet 31 may be in an overheated vapor state.

In the case of the working fluid, it is heated in the evaporator and becomes saturated or superheated steam. In the case of cooling fluid, it is required to be heated while cooling down, and to be heated to at least the saturation vapor state. As it can become saturated in the process of expansion in the turbine and even lower in saturation qualities, which can cause mechanical damage or corrosion of the turbine blades.

On the other hand, the cooling channel 33 passes through the rear surface of the turbine 20 for smooth flow of the cooling fluid. The working fluid in the working fluid inlet 31 through the evaporator and the cooling fluid drawn out from the pump outlet end have theoretically the same pressure and actually have a very similar pressure. The centrifugal force of the cooling fluid flow generated by the rotation of the turbine 20 and the centrifugal force of the rear portion of the turbine 20 and the center portion of the center portion of the turbine 20, In order to utilize the minute pressure gradient of the cooling fluid flow in accordance with the difference in linear velocity of the cooling fluid.

Meanwhile, the cooling method of the ORC-based generator according to the present invention uses a part of the working fluid at the outlet of the pump as a cooling fluid inside the housing of the generator, uses the evaporated cooling fluid as the working fluid of the turbine after cooling It corresponds to cooling method of ORC based generator. The cooling fluid is first introduced into the stator 14 through the cooling fluid inlet 32 formed by penetrating the outer circumferential surface 17 and the inner circumferential surface 16 of the stator 14, .

The cooling fluid introduced into the stator 14 through the cooling flow path 33 extending from the outlet of the cooling fluid inlet 32 to the rear surface of the turbine 20 is evaporated while cooling the interior of the housing To the backside of the turbine (20).

The cooling fluid introduced from the cooling flow path 33 flows through the turbine rear flow path 35 located at the rear surface of the turbine 20 to the working fluid inlet 31 And the cooling fluid introduced into the working fluid inlet 31 is merged with the working fluid at the inlet end of the turbine 20.

Meanwhile, it is preferable that a cooling fluid regulating valve 34 connected to the cooling fluid inlet 32 is provided to control the flow rate of the cooling fluid.

The cooling fluid regulating valve 34 may control the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling channel 33 leading to the working fluid inlet 31 may become an overheated steam state .

Meanwhile, the ORC-based power generation apparatus and method according to the present invention is related to a power generation apparatus and method including the above-described ORC-based generator cooling system and method. Therefore, detailed description of the same technical features as the cooling system and method of the ORC-based generator described above will be omitted.

1 and 2 illustrate a generator having a pair of turbines arranged opposite to each other. However, this is an embodiment of the present invention, in which a single turbine coupled to only one end of the rotary shaft 11 is used Also,

However, when a pair of opposed turbines is used, the following problems can be solved and additional effects can be generated.

A general turbine including a steam turbine is formed such that the back pressure P2 of the turbine into which the working fluid is introduced is higher than the front pressure P1 of the turbine from which the working fluid is discharged due to intrinsic characteristics resulting from the entire mechanism from the flow of the working fluid. Due to the pressure difference between the front and rear surfaces of the turbine, as shown in Fig. 4, axial load is generated in the turbine front direction (arrow direction) in accordance with the pressure difference. In a general power generation apparatus, in order to support such an axial load generated in the turbine, a thrust bearing perpendicular to the axial direction of the rotary shaft connected to the turbine is placed, or a ball bearing for sharing the axial load is provided It is common. However, when excessive axial load is generated, the increased friction of the bearings, or even damage to the bearings, causes damage to the entire rotating body of the turbine and the generator, resulting in a large loss. Therefore, in order to fundamentally prevent such a breakage problem, it is required to structurally cancel the load in the axial direction. Particularly, in the case of using an air-bearing or a gas-bearing having a low range of the support load instead of the thrust bearing or the ball bearing described above, the problem of the breakage becomes more serious.

Therefore, in order to solve such a problem, it may be considered to provide a pair of turbines 20 so that the rear surfaces of the turbines are opposed to each other at both ends of the rotating shaft 11 so as to face each other. In this case, the axial load generated in each turbine can be structurally canceled.

The positional relationship of the upper, lower, left, right, etc. used to describe the preferred embodiment of the present invention is described with reference to the accompanying drawings, and the positional relationship thereof may vary according to the embodiment.

It is also to be understood that, unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs will be. Further, unless explicitly defined in the present application, it should not be interpreted as an ideal or overly formal sense.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, You should see.

11:
12: Rotor
13: Coil
14: stator
15: coil winding section
16: inner peripheral surface
17:
20: Turbine
31: working fluid inlet
32: cooling fluid inlet
33:
34: Cooling fluid regulating valve
35: Turbine rear flow path

Claims (14)

A rotating shaft (11) connected to the turbine (20) and rotating together with the turbine (20); A rotor 12 coupled to a central portion of the rotary shaft 11 so as to be rotatable together with the rotary shaft 11; And a cylindrical stator (14) located at a radial outer radius of the rotor (12), the cooling system comprising:
A cooling fluid inlet 32 for introducing a part of the working fluid drawn out from the pump outlet end into the inside of the stator 14 as a cooling fluid is formed so as to penetrate the outer circumferential surface 17 and the inner circumferential surface 16 of the stator 14, );
The cooling fluid introduced into the stator 14 from the outlet of the cooling fluid inlet 32 to the backside of the turbine 20 performs cooling inside the housing and can flow to the backside of the turbine 20. [ A cooling flow path (33) for providing a flow path having a flow path; And
The cooling fluid is introduced from the cooling fluid passage 33 into the working fluid inlet 31 connected to the inlet end of the turbine 20 by centrifugal force generated by the rotation of the turbine 20, And a turbine rear-side flow path (35)
Wherein a part of the working fluid at the outlet of the pump is taken out and used as a cooling fluid, and the cooling fluid evaporated inside the housing is used again as a working fluid for the turbine (20).
The method according to claim 1,
Further comprising a cooling fluid regulating valve (34) connected to the inlet of the cooling fluid inlet (32) to regulate the flow rate of the cooling fluid.
3. The method of claim 2,
Wherein the cooling fluid control valve (34) adjusts the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling channel (33) leading to the working fluid inlet (31) Generator cooling system.
A cooling method of an ORC-based generator that draws a part of a working fluid at an outlet end of a pump to use as a cooling fluid inside a housing of a generator and uses the evaporated cooling fluid as a working fluid of a turbine (20)
Flowing cooling fluid into the stator (14) through a cooling fluid inlet (32) formed through the outer circumferential surface (17) and the inner circumferential surface (16) of the stator (14);
The cooling fluid introduced into the stator 14 through the cooling flow path 33 extending from the outlet of the cooling fluid inlet 32 to the rear surface of the turbine 20 is evaporated while cooling the interior of the housing, (20);
The cooling fluid introduced from the cooling flow path 33 flows through the turbine rear surface flow path 35 located on the rear surface of the turbine 20 to the inlet end of the turbine 20 using the centrifugal force resulting from the rotation of the turbine 20, To the working fluid inlet (31) side connected to the working fluid inlet (31); And
The cooling fluid introduced into the working fluid inlet (31) side merges with the working fluid at the inlet end of the turbine (20);
Wherein the ORC-based generator has a cooling function.
5. The method of claim 4,
Wherein a cooling fluid regulating valve (34) connected to the cooling fluid inlet (32) is provided to control the flow rate of the cooling fluid.
6. The method of claim 5,
Wherein the cooling fluid control valve (34) adjusts the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling channel (33) leading to the working fluid inlet (31) Cooling method of generator.
A rotating shaft (11) connected to the turbine (20) and rotating together with the turbine (20); A rotor 12 coupled to a central portion of the rotary shaft 11 so as to be rotatable together with the rotary shaft 11; And a cylindrical stator (14) located at an outer radius of rotation of the rotor (12), the ORC-
A cooling fluid inlet 32 for introducing a part of the working fluid drawn out from the pump outlet end into the inside of the stator 14 as a cooling fluid is formed so as to penetrate the outer circumferential surface 17 and the inner circumferential surface 16 of the stator 14, );
The cooling fluid introduced into the stator 14 from the outlet of the cooling fluid inlet 32 to the backside of the turbine 20 performs cooling inside the housing and can flow to the backside of the turbine 20. [ A cooling flow path (33) for providing a flow path having a flow path; And
The cooling fluid flowing from the cooling channel 33 positioned on the rear surface of the turbine 20 is directed toward the working fluid inlet 31 connected to the inlet end of the turbine 20 using the centrifugal force generated by the rotation of the turbine 20 A turbine rear-surface flow path (35)
Wherein a part of the working fluid at the outlet end of the pump is drawn out and used as a cooling fluid, and the cooling fluid evaporated inside the housing is used again as a working fluid for the turbine (20).
8. The method of claim 7,
Further comprising a cooling fluid regulating valve (34) connected to the inlet of the cooling fluid inlet (32) to regulate the flow rate of the cooling fluid.
9. The method of claim 8,
Wherein the cooling fluid control valve (34) adjusts the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling channel (33) leading to the working fluid inlet (31) Generator.
8. The method of claim 7,
The turbines 20 are arranged in pairs and are respectively connected to both ends of the rotary shaft 11 so that the rear surfaces of the turbines 20 are opposed to each other to face each other, Wherein the ORC-based power generation apparatus comprises:
11. The method of claim 10,
Wherein the pair of turbines (20) are formed to generate an axial load of the same magnitude.
A cooling method in which a part of the working fluid at the outlet end of the pump is taken out and used as a cooling fluid inside the housing of the generator and the evaporated cooling fluid is used again as the working fluid of the turbine As a result,
Flowing cooling fluid into the stator (14) through a cooling fluid inlet (32) formed through the outer circumferential surface (17) and the inner circumferential surface (16) of the stator (14);
The cooling fluid introduced into the stator 14 through the cooling flow path 33 extending from the outlet of the cooling fluid inlet 32 to the rear surface of the turbine 20 is evaporated while cooling the interior of the housing, (20);
The cooling fluid introduced from the cooling flow path 33 flows through the turbine rear surface flow path 35 located on the rear surface of the turbine 20 to the inlet end of the turbine 20 using the centrifugal force resulting from the rotation of the turbine 20, To the working fluid inlet (31) side connected to the working fluid inlet (31); And
The cooling fluid introduced into the working fluid inlet (31) side merges with the working fluid at the inlet end of the turbine (20);
And a cooling method comprising: < RTI ID = 0.0 > a < / RTI >
13. The method of claim 12,
A cooling fluid regulating valve (34) connected to the cooling fluid inlet (32) is provided to control the flow rate of the cooling fluid.
14. The method of claim 13,
Characterized in that the cooling fluid regulating valve (34) regulates the flow rate of the cooling fluid so that the cooling fluid at the end of the cooling channel (33) leading to the working fluid inlet (31) / RTI >

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