KR101070907B1 - Turbine having variable vane - Google Patents

Abstract

The present invention simplifies the system by eliminating the complicated control scheme of the conventional variable vanes and controlling the movement of the variable vanes using only a few drive means depending on the flow conditions at the turbine inlet such as the flow rate of the working fluid. An object of the present invention is to provide a variable vane type turbine and a turbine generator having the same, which can dramatically improve the price competitiveness. To this end, in the present invention, the turbine housing; A turbine wheel installed in the turbine housing and rotatably supported by a rotating shaft; A vane ring rotatably fixed to the housing by a predetermined angle; A motor for rotationally driving the vane ring; A connecting rod having one end eccentrically rotated with the rotation shaft of the motor and the other end rotatably fixed to one side of the vane ring; And one end is rotatably fixed to the turbine housing and the other end is rotatably fixed to the vane ring.

Description

Turbine having variable vane

1 is a view showing a schematic configuration of a conventional turbine generator.

2 is a view showing the configuration of a conventional variable vane type turbine.

3 shows a configuration of a variable vane turbine according to the present invention.

4 is an enlarged view of portion IV of FIG. 3;

Figure 5 is a graph showing the comparison of the distribution of the fuel cell stack pressure in the fuel cell turbine generator before and after applying the variable vane turbine according to the present invention.

Description of the Related Art

1: power generation unit 2: air supply (compressor)

3: fuel cell 4: combustor

6: variable vane 7: turbine wheel

8: controller 10, 160: turbine

61, 161: variable vane 71: turbine blade

161a, 161b: variable vane end 161c: slot

162: vane ring 163: connecting link

164: motor 165: turbine housing

166: disk

The present invention relates to a turbine, and more particularly, to a variable vane type turbine in which a variable vane is installed to enable the turbine to operate under a predetermined range despite operating fluctuations in the flow rate of the working fluid.

Usually, a turbine which is applied to an air supply (or air compressor), an auxiliary power unit (APU), a turbo charger, or the like for a fuel cell is designed in consideration of a high flow rate and a low flow rate. In particular, the fuel cell air supply must supply air having an appropriate amount of flow rate, pressure and temperature required by the stack of the fuel cell. The air supply is driven by a turbine which is coaxially connected with its axis of rotation. As a result, the turbine wheel should be able to rotate at an appropriate speed even when the flow rate of the combustion gas injected into the turbine wheel driving the air supply varies. That is, even in a range where the flow rate of the combustion gas is small, it is adjusted to the desired flow rate and pressure of the combustion gas, thereby rotating the turbine at a required speed, thereby rotating the rotation shaft of the air supply coaxially connected with the turbine shaft at the required speed, Air must be supplied to the fuel cell. This requires the use of variable vanes at the turbine inlet to regulate the flow and pressure of the combustion gases entering the turbine.

1 is a view schematically showing the configuration of a turbine generator including a variable vane type turbine.                         

As shown in FIG. 1, the turbine generator includes an air supply 2, a fuel cell 3, a combustor 4, a turbine 10, and a power generation unit 1. The power generation unit 1 may be provided with a driving motor for driving the air supply 2 in the initial operation. The initial operation of the turbine generator is started by the drive motor, and the air supply 2 is operated. The air supplier 2 functions to suck air, compress it, and transport the air to the fuel cell 3. The fuel cell 3 mixes the air transferred through the air supply 2 with fuel at an appropriate mixing ratio and sends the fuel to the combustor 4.

The combustor 4 burns fuel mixed with air to generate combustion gas and sends it to the turbine 10.

The turbine 10 typically has vanes and a turbine wheel 7 which adjusts the combustion gas to be evenly injected onto the turbine wheel 7. For the same reason as described above, it is preferable that a variable vane 6 is installed in the turbine coaxially connected with the fuel cell air supply 2. The variable vanes 6 serve to control the combustion gas to collide with the turbine wheel 7 at a predetermined pressure and flow rate. Thus, the turbine wheel 7 is rotated so that the energy of the working fluid is converted into the rotational energy of the rotating shaft to which the turbine wheel 7 is fixed.

As the turbine wheel 7 rotates, the magnetic rotor (not shown) of the power generation unit 1 integrally coupled to the rotary shaft of the turbine wheel 7 rotates. The magnetic rotor is rotated in a state in which a magnetic field is formed by a stator (not shown) around the magnetic rotor, thereby generating a current while changing the magnetic field formed by the stator to function as a generator.

2 is a plan view of a conventional variable vane type turbine.

As shown in FIG. 2, the conventional variable vane type turbine has a turbine wheel 7 in the center and variable vanes 61 disposed therein. The variable vanes 61 are rotatably coupled to one side of the turbine housing (not shown), and are arranged at equal intervals along the circumference of the turbine housing. The arranged variable vanes 61 are controlled to rotate at the same angle relative to the turbine housing by means of a separate hydraulic system (not shown) which is externally installed. Hydraulic systems used for such control require sensors to detect the flow rate of the working fluid, such as combustion gases, and hydraulic devices such as hydraulic actuators. That is, the flow rate of the working fluid that senses the flow rate of the working fluid and drives the actuator to rotate the respective variable vanes by a predetermined angle to adjust the flow rate of the working fluid impinging on the turbine blade 71 of the turbine wheel (7). In order to equip these hydraulic devices, the manufacturing cost is high, the nonlinear characteristics of the hydraulic devices are difficult to control, and the system is complicated.

The present invention is to solve the above problems, the present invention is to overcome the complicated control scheme of the conventional variable vanes, using only a small number of drive means depending on the flow conditions at the turbine inlet, such as the flow rate of the working fluid An object of the present invention is to provide a variable vane type turbine and a turbine generator having the same, which can simplify the system and significantly improve the cost competitiveness by controlling the movement of the variable vanes.

An object of the present invention as described above, the turbine housing; A turbine wheel installed in the turbine housing and rotatably supported by a rotating shaft; A vane ring rotatably fixed to the housing by a predetermined angle; A motor for rotationally driving the vane ring; A connecting rod having one end eccentrically rotated with the rotation shaft of the motor and the other end rotatably fixed to one side of the vane ring; And one end is rotatably fixed to the turbine housing and the other end is rotatably fixed to the vane ring.

Here, the rotation axis of the motor is disposed in parallel with the rotation axis of the turbine wheel, the connecting rod is preferably disposed at a predetermined angle with the center line connecting the rotation axis of the motor and the rotation axis of the turbine wheel.

Here, a disk having a predetermined diameter is attached to an end of the rotating shaft of the motor, and one end of the connecting rod is preferably fixed to the disk by a pin joint rotatable about an axis parallel to the rotating shaft of the turbine wheel. .

Here, one end of the connecting rod is preferably fixed to the vane ring by a pin joint rotatable about an axis placed in parallel with the axis of rotation of the turbine wheel.

Here, both ends of the variable vanes are fixed to the vane ring and the housing by pin joints rotatable about an axis parallel to the axis of rotation of the turbine wheel, and the variable vanes are pin joints at any one or more of both ends. It is preferred that a slot is formed in which is movable.                     

Here, it is preferable to further include a sensor for detecting the flow rate of the working fluid flowing into the turbine housing.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a view showing the configuration of a variable vane type turbine according to the present invention, and FIG. 4 is an enlarged view of the IV portion of FIG. 3.

As shown in FIGS. 3 and 4, the variable vane type turbine 160 according to the present invention includes a turbine housing 165, a turbine wheel 7, a vane ring 162, a motor 164, and a connecting rod ( 163 and variable vanes 161.

The turbine housing 165 may have a hollow portion for receiving the turbine wheel 7 coupled to the rotating shaft, and may be manufactured integrally with the housing for receiving the motor 164.

The turbine wheel (7) is supplied from the outside and the turbine blade (71) is coupled a plurality along its periphery so that it can rotate by the flow of high temperature and high pressure passed through the variable vane (161), the rotating shaft is in the center It is housed in the hollow portion of the turbine housing 165 in a coupled state.

The vane ring 162 is rotatably fixed to the housing by a predetermined angle as the motor 164 rotates. The vane ring 162 has a hollow portion for accommodating the turbine wheel 7 while being disposed in the turbine housing 165.

The motor 164 serves to drive the vane ring 162, and it is preferable that the motor 164 is a rotation driving means that can easily control the rotation angle and the rotation direction like the step motor 164, and the turbine housing 165 Is installed on the outside. A disk 166 or a link having a predetermined diameter is fixed to an end of the rotation shaft of the motor 164.

One end of the connecting rod 163 is rotatably fixed to the disk 166 or the link fixed to the motor 164, and the other end of the connecting rod 163 is rotatably fixed to one side of the vane ring 162.

The variable vane 161, one end is rotatably fixed to the turbine housing 165, the other end is rotatably fixed to the vane ring 162. The variable vane 161 may be coupled to the fixed portions at both ends by pin joints 161a and 161b, and the slots 161c may be formed at at least one of the fixed portions at both ends. A pin joint 161a or 161b of the fixing portion may move a predetermined distance along the slot. As shown in FIGS. 3 and 4, the variable vane 161 may be in the form of a symmetrical foil having a generally smooth curved shape, but the shape of the variable vane 161 is not limited thereto and is asymmetrical. It is also possible to have

The axis of rotation of the motor 164 is disposed in parallel with the axis of rotation of the turbine wheel (7), the connecting rod 163 and the center line connecting the axis of rotation of the motor 164 and the axis of rotation of the turbine wheel (7) and It is preferable to arrange | position in the state which makes a predetermined angle.

In the connecting rod 163 and the variable vane 161, portions of the connecting rods 163 and the variable vanes 161 are rotatably coupled to the rotary shaft of the turbine wheel 7 or the rotary shaft of the motor 164. It is preferable to combine with pin joints.                     

Hereinafter, a method of operating the variable vane type turbine having the above configuration will be described.

The vane ring 162 may be rotated by a predetermined angle by adjusting the rotation direction and angle of the motor 164. For example, in the situation as shown in FIG. 3, when the flow rate of the high temperature and high pressure fluid flowing into the turbine housing 165 decreases, the motor 164 is rotated by a predetermined angle clockwise. In this case, the vane ring 162 is rotated a predetermined angle counterclockwise while the connecting rod 163 is slightly lowered. Accordingly, the variable vanes 161 are laid down in a counterclockwise direction, and the flow passage between the variable vanes 161 is narrowed, and the fluid for rotating the turbine wheel 7 despite the reduced flow rate. The energy of can be maintained as it is. The movement of the variable vane 161 is guided by the slot, so that the movement of the variable vane 161 may be free even when the diameter of the vane ring 162 does not change.

On the contrary, when the flow rate of the high temperature and high pressure fluid flowing into the turbine housing 165 increases, the motor 164 is rotated a predetermined angle counterclockwise. Through the same action, the flow path between the variable vanes 161 is widened and the energy of the fluid for rotating the turbine wheel 7 can be maintained in spite of the increased flow rate.

By using this action, a sensor (not shown) is further installed to detect the flow rate of the working fluid flowing into the turbine housing 165, and the motor 164 is installed according to the flow rate of the working fluid detected by the sensor. By adjusting the rotational angle of c), it is possible to construct a system for continuously maintaining the rotational speed of the turbine wheel 7 within a predetermined variation range.

The variable vane type turbine according to the present invention described so far can be used in a turbine generator having a configuration as shown in FIG. 1. In particular, in the turbine generator shown in FIG. 1, the air supply must be continuously driven at a required speed in order to continuously supply the amount of air required by the stack of fuel cells. This requires the turbine to continuously generate rotational energy at the required speed, even when the flow rate of the gas entering the turbine driving the air supply is varied.

FIG. 5 is a graph showing the performance improvement when the variable vane type turbine according to the present invention is applied to a turbine generator system as shown in FIG. 1.

In FIG. 5, ⓐ, ⓑ, ⓒ and ⓓ are lines obtained by fitting the operating points of the turbine and the compressor, that is, operating points, when the vanes having a fixed flow path cross section are used. From the maximum value of the flow path cross section formed between the variable vanes of the turbine, the line obtained by fitting the operating points in the case of having a fixed flow path cross section of ⓐ is 100%, ⓑ is 80%, ⓒ is 60%, and ⓓ is 40% to be. In addition, ① and ② are lines connecting the operating points required during operation in the fuel cell stack. That is, in the case of using a turbine having a fixed flow path cross-sectional area, the pressure in the fuel cell stack changes along lines ⓐ, ⓑ, ⓒ and ⓓ or above, as the mass flow rate changes. Therefore, when the required operating points such as ① and ② vary in various ways, a turbine having vanes having a fixed flow path cross section cannot cope with this. As with the variable vane type turbine according to the present invention, the variable vane type turbine which can adjust the flow path cross-sectional area as the mass flow rate of the incoming working fluid is changed must be used to control the pressure of the fuel cell stack in the fuel cell system. To achieve the desired performance.

As described above, according to the present invention, there is provided a variable vane type turbine capable of maintaining the rotational speed of the turbine wheel within a predetermined range by controlling only one motor in accordance with the flow conditions at the turbine inlet, such as the flow rate of the working fluid. can do.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (7)

Turbine housing; A turbine wheel installed in the turbine housing and rotatably supported by a rotating shaft; A vane ring rotatably fixed to the housing by a predetermined angle; A motor for rotationally driving the vane ring; A connecting rod having one end eccentrically rotated with the rotation shaft of the motor and the other end rotatably fixed to one side of the vane ring; And A variable vane type turbine, characterized in that one end is rotatably fixed to the turbine housing, and the other end is rotatably fixed to the vane ring. The method of claim 1, The axis of rotation of the motor is disposed in parallel with the axis of rotation of the turbine wheel, The connecting rod is a variable vane-type turbine, characterized in that arranged at a predetermined angle with the center line connecting the rotating shaft of the motor and the rotating shaft of the turbine wheel. The method of claim 1, A disk having a predetermined diameter is attached to an end of the rotating shaft of the motor, One end of the connecting rod is a variable vane type turbine, characterized in that fixed to the disk with a rotatable pin joint about an axis placed parallel to the axis of rotation of the turbine wheel. The method of claim 1, One end of the connecting rod is a variable vane type turbine, characterized in that the vane ring is fixed with a rotatable pin joint about an axis parallel to the axis of rotation of the turbine wheel. The method of claim 1, Both ends of the variable vane is fixed to the vane ring and the housing is fixed by a pin joint rotatable about an axis parallel to the axis of rotation of the turbine wheel. The method of claim 5, The variable vane is a variable vane type turbine, characterized in that the slot is formed at any one or more ends of the pin joint to move. The method of claim 1, And a sensor for sensing a flow rate of the working fluid flowing into the turbine housing.

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