KR20170034717A - Apparatus for detecting crack of state coil of generator - Google Patents

Abstract

According to the present invention, an apparatus for determining a defect of a stator coil of a generator allows hydrogen accommodated outside a coil of a stator of a generator to flow into the coil by a defect in the coil to dissolve in a coolant flowing in the coil, discharges the coolant out of the generator to store the coolant in a coolant tank, measures a hydrogen concentration in air accommodated in the stored coolant tank to determine whether the coil of the stator of the generator is defective, and comprises: a dual pump including a centrifugal pump to generate a suction force by rotation of a motor, and an air extraction pump to generate a suction force by decreasing a pressure therein by reducing a cross sectional area of a passage in which air flowing thereinto moves; a hydrogen concentration measurement unit to measure a hydrogen concentration of air discharged to the coolant tank; and a control unit to selectively drive the centrifugal pump or the air extraction pump. According to an embodiment of the present invention, since air in the coolant tank is discharged to the outside, the coolant in the coolant tank is not contaminated.

Description

[0001] APPARATUS FOR DETECTING CRACK OF STATE COIL OF GENERATOR [0002]

The present invention relates to a defect determination apparatus for a generator stator winding.

Referring to FIGS. 1 and 2, a high-pressure hydrogen gas is filled in a generator case 10 in which a stator winding is installed. The stator winding 20 is configured such that the cooling water flows into one side of the winding 21 through the cooling water inflow conduit 30 connected to the cooling water tank 50 and flows along the winding 21 and then through the cooling water outflow conduit 40, And then discharged to the tank 50 to cool the winding wire 21.

On the other hand, since the stator winding 20 is installed inside the case 10, it is difficult to visually confirm whether or not a defect has occurred. 2, when the defects 23 are generated in the stator winding 20, the hydrogen gas contained in the case 10 flows into the defective portion and flows into the cooling water tank 50).

Whether or not a defect has occurred in the conventional stator winding 20 is determined by measuring the hydrogen content in the cooling water flowing into the cooling water tank 50 or measuring the content of the hydrogen gas contained in the cooling water tank 50 by evaporation, Or more of the hydrogen content is detected, it is determined that the defect 23 is generated in the stator winding 20.

For example, an apparatus for determining whether a stator winding is defective has a structure in which external air is introduced into a cooling water tank 50 through an air sucking unit 51, a hydrogen concentration is detected through a measuring instrument 52, It was a method to detect gas inflow.

However, in the prior art, when external air is supplied to the cooling water tank 50, there is a problem that the conductivity of the cooling water gradually increases as the cooling water is contaminated by the supplied air.

Due to such a problem, a large amount of air can not be supplied to the cooling water tank 50 because the air must be supplied to monitor the conductivity. Thus, it takes a long time to completely discharge the hydrogen gas contained in the cooling water tank 50.

According to one aspect of the present invention, there is provided a method of controlling a hydrogen gas concentration in an air contained in a cooling water tank by discharging air from a cooling water tank to the outside without supplying external air to the cooling water tank. And to provide a defect judging device for a generator stator winding to be measured.

In order to achieve the above-mentioned object, as one aspect, a defect occurs in the generator stator winding, hydrogen contained in the outside of the winding wire flows into the winding wire to dissolve in the cooling water flowing inside the winding wire, and the cooling water is discharged to the outside of the generator, And determining the deficiency of the generator stator winding by measuring the hydrogen concentration in the air stored in the stored cooling water tank, the apparatus comprising: a centrifugal pump for generating a suction force by rotation of the motor; A double pump section including an air extraction pump in which a suction force is generated as the internal pressure decreases due to a decrease in the cross sectional area of the passage through which the incoming air moves, and a double pump section for measuring the hydrogen concentration of the air discharged into the cooling water tank And selectively drives the centrifugal pump or the air extraction pump And a controller for controlling the generator stator winding.

According to an embodiment of the present invention, the control unit drives the air extraction pump when the hydrogen concentration is equal to or higher than the set value, and drives the centrifugal pump when the hydrogen concentration is lower than the set value.

According to one embodiment of the present invention, the double pump unit is characterized in that the suction force varies depending on the speed of the air to be introduced.

According to an embodiment of the present invention, the double pump unit further includes a three-way valve for introducing the air discharged from the cooling water tank into the centrifugal pump or the air extraction pump, and the control unit controls the opening and closing of the three- The centrifugal pump or the air extraction pump can be selectively driven.

According to an embodiment of the present invention, there is further provided a pressure regulating valve for regulating the pressure of the compressed air introduced into the air extracting pump, wherein the controller adjusts opening and closing of the pressure regulating valve, The suction force can be controlled.

According to an embodiment of the present invention, the control unit may adjust the driving time and the driving period of the double pump unit according to the hydrogen concentration measured by the hydrogen concentration measuring unit.

According to an embodiment of the present invention, the control unit may include a display unit for displaying information inputted to the control unit.

As described above, according to the embodiment of the present invention, since the air in the cooling water tank is discharged to the outside, the cooling water accommodated in the cooling water tank is not contaminated.

According to an embodiment of the present invention, the amount of air discharged from the cooling water tank can be adjusted according to the measured hydrogen concentration.

FIG. 1 and FIG. 2 are simplified views of a conventional defect determination apparatus for a stator winding.
FIG. 3 is a schematic view of a defect determination apparatus for a generator stator winding according to an embodiment of the present invention.

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

First, the embodiments described below are suitable for understanding the defect determination apparatus 100 of the generator stator winding of the present invention. It should be understood, however, that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

The apparatus for determining defects of a generator stator winding according to an embodiment of the present invention includes a hydrogen concentration measuring unit 130 for measuring a hydrogen content of air contained in a cooling water tank 110 into which coolant is introduced and stored, And a double pump unit 120 for supplying a suction force to discharge the air contained in the cooling water tank 110 to the hydrogen concentration measuring unit 130.

Referring to FIG. 3, the double pump unit 120 according to an embodiment of the present invention includes a centrifugal pump 121 for generating a suction force by rotation of a motor, a cross-sectional area And an air extraction pump 122 in which a suction force is generated as the internal pressure decreases.

The centrifugal pump 121 according to an embodiment of the present invention corresponds to various known centrifugal pumps 121 driven by a motor. When the cross-sectional area of the fluid flowing through the air-extracting pump 122 is relatively large and passes through a small point, the velocity of the fluid decreases and the pressure increases at a large cross-sectional area. It is a pump using the Bernoulli principle in which the pressure rises and the pressure decreases.

3, the air extracting pump 122 according to an embodiment of the present invention is introduced into the pump, the outflowed portion S2 has a large cross-sectional area, a portion S1 having a small cross- The pressure is lowered when the air supplied from the air supply unit 180 passes through the center portion S1 having a small cross sectional area, and a suction force is generated in the air extraction pump 122. [

In addition, the air extraction pump 122 according to an embodiment of the present invention receives compressed air from the air supply unit 180, and the compressed air is supplied to the pressure regulating valve 124 The speed can be adjusted by

Therefore, when the air is introduced at a relatively high speed by the air extraction pump 122, the pressure becomes lower at the central portion to increase the suction force, and when the air flows at a relatively slow speed, the pressure drop becomes lower, Can be lowered.

The dual pump unit 120 according to an embodiment of the present invention may further include the centrifugal pump 121 and the centrifugal pump 121 to selectively drive the centrifugal pump 121 or the air- And a control unit connected to and controlling the air extraction pump 122.

For example, when the hydrogen concentration is measured to be high, the air extraction pump 122 is driven to discharge the air contained in the cooling water tank 110 at a high speed. When the hydrogen concentration is lower than the set value, The pump 121 can be driven to discharge the air from the cooling water tank 110 to the outside.

The double pump unit 120 according to an embodiment of the present invention may be configured such that the air sucked in the cooling water tank 110 is selectively introduced into the centrifugal pump 121 or the air- And the control unit may control the opening and closing of the three-way valve 123 so that the air discharged from the cooling water tank 110 flows through the centrifugal pump 121 or the air extraction pump 122 ). ≪ / RTI >

The controller according to an embodiment of the present invention may be connected to the pressure regulating valve 124 to control the opening and closing of the pressure regulating valve 124 to adjust the speed of the air flowing into the air- The suction force of the air extraction type pump 122 can be controlled.

For example, when the hydrogen concentration is high, opening and closing of the pressure regulating valve 124 may be controlled so that the gas contained in the cooling water tank 110 is rapidly discharged to the outside of the cooling water tank 110, By increasing the air pressure introduced into the pump 122, the speed of the introduced air can be increased. Therefore, the suction force of the air extraction pump 122 is increased and the air inside the cooling water tank 110 can be discharged to the outside quickly.

In the case of discharging air from the cooling water tank 110 by the air extracting pump 122 according to an embodiment of the present invention, the hydrogen contained in the air can be calculated by the following equation (1).

Equation ^{(1) --- V (m 3} / day) = (D * V * 60 * 24) / 10 12 (D: the hydrogen gas concentration (ppm), V: discharged amount of air (cm ³ / min))

The control unit according to an embodiment of the present invention can control the driving period or the driving time of the double pump unit 120 according to the hydrogen concentration measured through the hydrogen concentration measuring unit 130.

For example, when the hydrogen concentration is high, the driving time of the double pump unit 120 may be extended to discharge the gas contained in the cooling water tank 110 to the outside of the cooling water tank 110, It can be set short.

In addition, the display unit 150 according to an embodiment of the present invention may display the information input to the controller through the display unit 150, such as a display unit, connected to the controller.

Hereinafter, the operation and effect of the defect determination apparatus 100 of the generator stator winding according to the embodiment of the present invention will be described.

When the double pump unit 120 according to an embodiment of the present invention is driven and a suction force is generated in the dual pump unit 120, the air contained in the cooling water tank 110, in which the cooling water discharged from the generator is stored, And then flows into the hydrogen concentration measuring unit 130. [ On the other hand, the condensed air containing hydrogen can be drained to the outside along the pipe P 2 without flowing into the hydrogen concentration measuring unit 130.

The hydrogen concentration measured by the hydrogen concentration measuring unit 130 is inputted to the control unit and the hydrogen concentration measured by the hydrogen concentration measuring unit 130 is supplied to the double pump unit 120 through the centrifugal pump The air extraction pump 122 is driven so that the air contained in the cooling water tank 110 flows into the double pump unit 120 and then is discharged to the outside.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the following claims It will be understood by those skilled in the art that the present invention can be easily understood by those skilled in the art.

100: defective judgment device of generator stator winding
110: cooling water tank
120: double pump section
121: Centrifugal pump
122: air extraction pump
123: Three-way valve
124: Pressure regulating valve
130: hydrogen concentration measuring section
140:
150: display means
160: generator
170: Water gauge
180: Air supply

Claims (7)

Hydrogen contained in the outside of the winding occurs due to a defect in the generator stator winding. The hydrogen stored in the cooling water tank is discharged to the outside of the generator and dissolved in the cooling water flowing in the winding. And determining whether the generator stator winding is defective, the apparatus comprising:
A double pump unit including a centrifugal pump for generating a suction force by rotation of a motor and an air extraction pump for generating a suction force due to a decrease in internal pressure due to a decrease in cross sectional area of a passage through which air flows into the interior;
A hydrogen concentration measuring unit for measuring a hydrogen concentration of the air discharged into the cooling water tank; And
And a controller for selectively driving the centrifugal pump or the air extraction pump. The method according to claim 1,
Wherein,
Wherein the air extraction pump is driven when the hydrogen concentration is equal to or higher than a set value and the centrifugal pump is driven when the hydrogen concentration is lower than a set value. 3. The method of claim 2,
The double-
And the suction force varies depending on the speed of the air flowing into the generator stator winding. The method according to claim 1,
The double pump unit may further include a three-way valve for introducing the air discharged from the cooling water tank into the centrifugal pump or the air extracting pump, wherein the control unit controls the opening and closing of the three- Wherein the pump is selectively driven. The method of claim 3,
Further comprising a pressure regulating valve for regulating the pressure of the compressed air introduced into the air extracting pump, wherein the controller controls the opening and closing of the pressure regulating valve to control the suction force of the air extracting pump Device for determining defects in generator stator windings. 6. The method of claim 5,
Wherein,
Wherein the driving time and the driving period of the double pump unit are adjusted according to the hydrogen concentration measured by the hydrogen concentration measuring unit. The method according to claim 6,
And display means for externally displaying the information input to the control portion.

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