JP2013198227A - Inner gas replacement method for rotary electric machine and inner gas replacement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inner gas replacement method for a rotary electric machine and an inner gas replacement device that can perform replacement work of inner gas in a period of time shorter than those of a conventional method, and a conventional device.SOLUTION: An inner gas replacement method for a rotary electric machine 1 includes a step of supplying inert gas for preventing mixture of hydrogen gas and air inside a lower pipe 7 installed at an inner lower portion of the rotary electric machine 1 at a stretch within an acceptable range of an inner pressure of the rotary electric machine 1, agitating the inert gas guided inside the rotary electric machine 1 from an inside of the lower pipe 7 via holes provided on a surface of the lower pipe 7 and the air existing inside the rotary electric machine 1 therein and filling an inside of the rotary electric machine 1 with the inert gas by guiding the air existing inside the rotary electric machine 1 inside an upper pipe 6 via holes provided on a surface of the upper pipe 6 installed at an inner upper portion of the rotary electric machine 1 and discharging the air outside the rotary electric machine 1.

Description

  The present invention relates to an in-machine gas replacement method and an in-machine gas replacement apparatus for a rotating electrical machine.

  A large turbine generator encloses hydrogen gas as a refrigerant in the machine. Since hydrogen gas is a flammable gas, it is referred to as an inert gas (hereinafter referred to as “intermediate replacement gas”) such as carbon dioxide gas or nitrogen gas so that the hydrogen gas is sealed in the generator without being mixed with air. ) Is used to replace the gas. The gas replacement is performed by utilizing a specific gravity difference between air, an intermediate replacement gas, and hydrogen. A method of replacing the gas in the rotating electrical machine by interposing such an intermediate replacement gas is described in, for example, Japanese Patent Application Laid-Open No. 2003-153502 (Patent Document 1).

JP 2003-153502 A

  However, the conventional gas replacement method in a rotating electrical machine as described in Patent Document 1 described above takes a lot of time. For example, in the invention described in Patent Document 1, it is necessary to perform work at such a low speed (flow rate) that hydrogen gas and the intermediate replacement gas do not stir, leading to an increase in replacement work time.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an in-machine gas replacement method and an in-machine gas replacement apparatus for a rotating electrical machine that can perform an in-machine gas replacement operation in a shorter time than before. And

  In order to solve the above-described problems, an in-machine gas replacement method for a rotating electrical machine according to an embodiment of the present invention supplies an inert gas to the in-machine pressure of the rotating electrical machine in a pipe of a lower pipe installed in a lower part of the rotating electrical machine. Supply at a stroke within an allowable range, and stir the inert gas guided into the rotating electrical machine from the hole formed in the lower pipe and the air present in the rotating electrical machine in the rotating electrical machine. The inert gas is introduced into the rotary electric machine by introducing the air into the pipe of the upper pipe through the hole formed in the upper pipe installed in the upper part of the rotary electric machine and releasing the air outside the machine. The first step of sealing, supplying hydrogen gas into the pipe of the upper pipe at a stretch within an allowable range of the internal pressure of the rotating electric machine, and the hydrogen gas guided into the rotary electric machine from the hole of the upper pipe and the Enclosed in a rotating electrical machine The inert gas being agitated in the rotary electric machine, and the inert gas sealed in the rotary electric machine is introduced into the lower pipe from the hole of the lower pipe and released to the outside of the machine. In the second step of sealing the hydrogen gas in the rotary electric machine, an inert gas is supplied into the lower pipe within a permissible range of the internal pressure of the rotary electric machine, and from the hole of the lower pipe. The inert gas introduced into the rotating electrical machine and the hydrogen gas sealed in the rotating electrical machine are stirred in the rotating electrical machine and sealed in the rotating electrical machine from the hole of the upper pipe. A third step of releasing the hydrogen gas enclosed in the rotary electric machine out of the machine by guiding the hydrogen gas being introduced into the pipe of the upper pipe and releasing it outside the machine; and the upper pipe The pressure in the machine of the rotating electrical machine Supplying at a stretch within an allowable range, stirring the air guided into the rotating electrical machine from the hole of the upper pipe and the inert gas sealed in the rotating electrical machine, in the rotating electrical machine, The inert gas sealed in the rotating electric machine is guided from the hole of the lower pipe into the pipe of the lower electric pipe and discharged outside the machine, so that the inert gas sealed in the rotating electric machine is machined. It is characterized by comprising at least one of the fourth steps of releasing to the outside.

  In order to solve the above-described problem, an in-machine gas replacement device for a rotating electrical machine according to an embodiment of the present invention is configured to connect an inert gas supply unit that supplies an inert gas and the interior of the rotating electrical machine via a regulating valve. An inert gas supply line that supplies the inert gas from the inert gas supply unit into the rotary electric machine, a hydrogen gas supply unit that supplies hydrogen gas, and a rotary valve. A hydrogen gas supply line that supplies the hydrogen gas from the hydrogen gas supply unit into the rotary electric machine, and a flow that connects the rotary electric machine and the atmosphere via a regulating valve. An air discharge line for releasing the gas remaining in the rotary electric machine to the outside of the machine, and a flow path for connecting the rotary electric machine and the compressed air supply device via a regulating valve, the compression Air from the air supply device An air intake line to be supplied, a gas supply valve of the inert gas supply unit, an adjustment valve of the inert gas supply line, a gas supply valve of the hydrogen gas supply unit, an adjustment valve of the hydrogen gas supply line, the atmosphere A valve control unit for controlling the opening degree of each of the regulating valve for the discharge line and the regulating valve for the air intake line, wherein the valve control unit supplies the inert gas received from the inert gas supply unit. The gas supply valve of the inert gas supply unit, the inert gas supply line based on the information of the amount, the supply amount of the hydrogen gas received from the hydrogen gas supply unit, and the supply amount of air received from the compressed air supply device And opening and closing at least one of a regulating valve for the hydrogen gas supply unit, a regulating valve for the hydrogen gas supply line, a regulating valve for the atmospheric discharge line, and a regulating valve for the air intake line. Scan supply line, the air discharge line, characterized by opening and closing control of the air intake line and the inert gas supply line.

  According to the present invention, the in-machine gas replacement operation can be performed in a shorter time than conventional.

Schematic which showed the structure of the conventional rotary electric machine gas replacement apparatus which is an example of the apparatus which implements the rotary electric machine gas replacement method which concerns on embodiment of this invention. Explanatory drawing explaining the intermediate | middle substitution gas enclosure process of the hydrogen gas enclosure procedure which the gas substitution method in the rotary electric machine which concerns on embodiment of this invention comprises. Explanatory drawing explaining the hydrogen gas enclosure process of the hydrogen gas enclosure procedure which the gas replacement method in the rotary electric machine which concerns on embodiment of this invention comprises. Explanatory drawing explaining the hydrogen gas discharge | release process of the hydrogen gas discharge | release procedure which the gas replacement method in the rotary electric machine which concerns on embodiment of this invention comprises. Explanatory drawing explaining the intermediate | middle substitution gas discharge | release process of the hydrogen gas discharge | release procedure which the gas substitution method in the rotary electric machine which concerns on embodiment of this invention comprises. Schematic which showed the structure of the gas replacement apparatus in rotary electric machines based on embodiment of this invention.

  Hereinafter, an in-machine gas replacement method and an in-machine gas replacement apparatus for a rotating electrical machine according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows an apparatus (hereinafter referred to as a “rotary electric machine gas replacement device”) that implements an in-machine gas replacement method (hereinafter referred to as a “rotary electric machine gas replacement method”) according to an embodiment of the present invention. .) Is a schematic diagram showing a configuration of a conventional rotary electric machine gas replacement device 10 as an example.

  The rotating electrical machine internal gas replacement device 10 uses an inert gas (intermediate replacement gas), hydrogen or air to prevent the gas (internal gas) existing in the hydrogen-cooled rotating electrical machine 1 from being mixed with hydrogen gas and air. This is an apparatus for replacing a gas in a rotating electrical machine and capable of performing a conventional gas replacing method in a rotating electrical machine. As the inert gas (intermediate replacement gas), for example, a gas mainly containing at least one selected from nitrogen, carbon dioxide, and a rare gas is applied.

  The rotating electrical machine internal gas replacement method according to the embodiment of the present invention uses, for example, a part or all of the existing rotating electrical machine internal gas replacement device 10 to convert the in-machine gas of the rotating electrical machine 1 into hydrogen gas or inert gas. Alternatively, the air can be replaced, that is, the in-flight gas can be replaced.

  The hydrogen-cooled rotary electric machine 1 is filled with hydrogen gas as a refrigerant that cools the inside of the machine during operation, and this hydrogen gas is circulated by a hydrogen cooling system (not shown) outside the machine, thereby rotating the rotary electric machine 1. The temperature rise due to the heat generated in is kept within a predetermined range. A shaft seal portion 4 is provided in the vicinity of the bearing 3 that supports the rotating shaft 2 of the rotating electrical machine 1, and the hydrogen gas sealed in the machine is sealed by the sealing oil supplied to the shaft seal portion 4. In addition, assuming that hydrogen gas is sealed and exhausted in the rotary electric machine 1, for example, an upper pipe 6 and a lower pipe 7 for supplying and releasing a gas such as hydrogen gas, an inert gas, and air as a refrigerant, Is provided. Reference numeral 9 denotes a manhole provided for in-flight access during inspection or the like.

  The upper pipe 6 supplies hydrogen gas from the hydrogen gas supply section 11 to the upper pipe 6 provided with a plurality of holes, and disperses the hydrogen gas from the holes of the upper pipe 6 to the outside of the pipe to introduce hydrogen gas into the machine. A line 12, an atmospheric discharge line 13 for releasing hydrogen gas as an in-machine gas from the upper pipe 6 to the atmosphere, an air is taken in from the outside of the machine and supplied to the upper pipe 6, and dispersed from the hole of the upper pipe 6 to the outside of the pipe. Thus, the air intake line 14 to be introduced into the machine is connected.

  In the rotating electrical machine 1, the hydrogen gas stored in the hydrogen gas supply unit 11 can be supplied from the hydrogen gas supply unit 11 to the upper pipe 6 through the hydrogen gas supply line 12. For example, in the rotating electrical machine 1 shown in FIG. 1, the hydrogen gas pressurized and stored in the hydrogen gas cylinder 15 that is the hydrogen gas supply source of the hydrogen gas supply unit 11 passes through the hydrogen gas supply valve 16 and is decompressed by the pressure reducing valve 17. Then, the pressure is supplied to the upper pipe 6 through the pipe 19 to which the adjustment valve 18 for adjusting the opening degree of the flow path connecting the pressure reducing valve 17 and the upper pipe 6 is attached. The hydrogen gas cylinder 15 as the hydrogen gas supply source is preferably prepared in advance in an amount corresponding to the internal volume, for example, three times the internal volume.

  Further, in the rotating electrical machine 1, hydrogen gas existing in the machine can be introduced into the pipe through the hole of the upper pipe 6, led to the atmospheric discharge line 13, and released into the atmosphere through the atmospheric discharge line 13. For example, in the rotating electrical machine 1 shown in FIG. 1, hydrogen gas existing in the machine is led into the upper pipe 6 from the hole of the upper pipe 6 and further led to the pipe 19 from the upper pipe 6. Thereafter, the hydrogen gas led to the pipe 19 is further led to the atmospheric discharge pipe 23 to which the regulating valve 21 and the regulating valve 22 for adjusting the opening degree of the flow path leading from the pipe 19 to the atmosphere are attached. 23 is released from the opening 23a into the atmosphere.

  Further, in the rotating electrical machine 1, air (dry air) taken from outside the machine can be supplied to the upper pipe 6 through the air intake line 14. For example, in the rotating electrical machine 1 shown in FIG. 1, the air intake pipe 26 to which the adjustment valve 25 is attached is connected to the pipe 19. By connecting a compressed air supply device 29 for supplying compressed dry air into the machine to the opening 26a of the air intake tube 26, the air supplied from the compressed air supply device 29 is supplied to the air intake tube 26, the pipe 19, and Then, it is guided to the upper pipe 6 and supplied into the machine.

  The lower pipe 7 includes an inert gas supply line 33 for introducing an inert gas such as nitrogen gas supplied from an inert gas supply unit 31 from the lower pipe 7 provided with a plurality of holes into the machine, and an in-machine gas. And an atmospheric discharge line 34 for releasing the inert gas to the atmosphere.

  In the rotating electrical machine 1, the inert gas stored in the inert gas supply unit 31 can be supplied from the inert gas supply unit 31 to the lower pipe 7 through the inert gas supply line 33. For example, in the in-machine gas replacement device 10 for a rotating electrical machine shown in FIG. 1, nitrogen gas is used as an inert gas. The amount of nitrogen gas used can be easily measured from its properties, and the gas replacement operation and in-machine gas concentration estimation can be easily performed in that it is less expensive than rare gases.

  In the rotating electrical machine 1 shown in FIG. 1, nitrogen gas pressurized and stored in a nitrogen gas cylinder 35 serving as an inert gas supply source passes through the nitrogen gas supply valve 36, is decompressed by the decompression valve 37, and the adjustment valve 38 is attached. It is supplied to the lower pipe 7 through the pipe 39 provided. The nitrogen gas cylinder 35 as an inert gas supply source is preferably prepared in advance in an amount corresponding to the internal volume, such as three times the internal volume.

  Further, in the rotating electrical machine 1, the inert gas present in the machine can be introduced into the pipe through the hole of the lower pipe 7, led to the atmospheric discharge line 34, and released into the atmosphere through the atmospheric discharge line 34. For example, in the rotating electrical machine 1 shown in FIG. 1, the inert gas existing in the machine is led into the lower pipe 7 from the hole of the lower pipe 7 and further led to the pipe 39 from the lower pipe 7. Thereafter, the inert gas led to the pipe 39 is led to the pipe 43 to which the adjustment valve 41 for adjusting the opening degree of the flow path connecting the pipe 39 and the atmospheric discharge pipe 23 is attached. It is guided to the atmospheric discharge pipe 23 and is released into the atmosphere from the opening 23a.

  On the other hand, the rotating electrical machine internal gas replacement device 10 includes a gas control panel 45 that monitors and controls the concentration (purity) and pressure of the in-machine gas of the rotating electrical machine 1, and an atmospheric discharge line 13 that connects the interior of the rotating electrical machine 1 and the atmosphere. , 34, and a scavenging board 46 for measuring the concentration (purity) of the gas.

  Here, reference numerals 51, 52, 53, and 54 denote a draft gauge, an in-machine pressure gauge, a gas purity meter, and an atmospheric discharge pipe, respectively. Reference numeral 56 denotes a gas purity meter. Further, reference numeral P1 denotes a branch point (junction point) between the pipe 19 and the atmospheric discharge pipe 23, reference numeral P2 denotes a branch point (junction point) between the pipe 19 and the air intake pipe 26, and reference numeral P3 denotes a pipe 39 and a pipe 43. A branch point (merging point), symbol P4, is a branch point (merging point) between the atmospheric discharge pipe 23 and the pipe 43 provided between the regulating valve 21 and the regulating valve 22 of the atmospheric discharge pipe 23.

  In the rotating electrical machine 1 shown in FIG. 1, the hydrogen gas supply line 12, the atmospheric discharge line 13, and a part of the air intake line 14 have a common flow path, but each is configured independently. In some cases. Further, the inert gas supply line 33 and the atmospheric discharge line 34 may be configured independently, similarly to the hydrogen gas supply line 12, the atmospheric discharge line 13, and the air intake line 14.

  Next, a gas replacement method for a rotating electrical machine according to an embodiment of the present invention will be described. The rotary electric machine gas replacement method according to the embodiment of the present invention described below is an example in the case of using the rotary electric machine gas replacement apparatus 10 shown in FIG.

  2 and 3 are explanatory views for explaining a hydrogen gas filling procedure provided in the gas replacement method for a rotating electrical machine according to the embodiment of the present invention, and FIGS. 4 and 5 illustrate the interior of the rotating electrical machine according to the embodiment of the present invention. It is explanatory drawing explaining the hydrogen gas discharge | release procedure which the gas replacement method comprises. Each of the regulating valves 18, 21, 22, 25, 38, and 41 shown in FIGS. 2, 3, 4, and 5 is a normally closed valve that is opened when necessary but normally closed.

  The in-machine gas replacement method of the rotating electrical machine according to the embodiment of the present invention is a method of replacing the gas (in-machine gas) present in the machine of the hydrogen-cooled rotating electrical machine 1 with an inert gas, hydrogen gas, or air. The gas replacement method for a rotating electrical machine according to an embodiment of the present invention includes a hydrogen gas sealing procedure (FIGS. 2 and 3) for sealing hydrogen gas in the rotating electrical machine 1 and a hydrogen gas release for releasing the hydrogen gas from the rotating electrical machine. At least one of the procedures (FIGS. 4 and 5) is provided.

  The hydrogen gas filling procedure is an intermediate replacement gas in which an inert gas is supplied from a state where the interior of the rotating electrical machine 1 is filled with air and the interior gas of the rotating electrical machine 1 is replaced with an inert gas (intermediate replacement gas) from the air. Rotating electrical machine by supplying hydrogen gas from the sealing step and a state where an inert gas (intermediate replacement gas) is sealed in the rotating electric machine 1 and replacing the in-machine gas of the rotating electric machine 1 from the inert gas to the hydrogen gas At least one of a hydrogen gas filling step of filling hydrogen gas in one machine.

  In addition, the hydrogen gas release procedure supplies an inert gas (intermediate replacement gas) from a state in which hydrogen gas is sealed in the rotating electrical machine 1 to replace the in-machine gas of the rotating electrical machine 1 from hydrogen gas to an intermediate replacement gas. Thus, the hydrogen gas releasing step for releasing hydrogen gas from the machine of the rotating electrical machine 1 and the supply of air from the state where the inert gas (intermediate replacement gas) is sealed in the machine of the rotating electrical machine 1 It comprises at least one step of an intermediate replacement gas releasing step of discharging the intermediate replacement gas from the inside of the rotating electrical machine 1 by replacing the in-machine gas with air from the intermediate replacement gas.

  In the intermediate replacement gas sealing step (FIG. 2), first, a discharge port for releasing air, which is an in-machine gas, from the upper pipe 6 into the atmosphere is secured. More specifically, among the regulating valves 18, 21, 22, 25, 38, 41 that are normally closed valves, the regulating valves 21, 22 are opened, and the upper pipe 6 is connected to the pipe 19, the regulating valve 21, the regulating valve 22. And a state connected to the atmosphere via the atmosphere discharge pipe 23 (atmospheric release state).

  Subsequently, nitrogen gas as an inert gas (intermediate replacement gas) stored in the inert gas supply unit 31 is supplied to the lower pipe 7. More specifically, after slightly opening the adjustment valve 38 and confirming that the sound of the gas flowing through the pipe 39 is not different from the sound generated during normal time and whether there is an increase in the in-machine pressure measured by the in-machine pressure gauge 52 Then, the regulating valve 38 is further opened.

  The opening degree of the regulating valve 38 is maximized within a range where the in-machine pressure does not exceed a preset safety limit pressure upper limit value. That is, nitrogen gas is supplied into the machine as quickly as possible. The supply speed of nitrogen gas (supply amount per unit time) is determined according to the exhaust capacity (exhaust amount per unit time) of the atmospheric discharge line 13 on the exhaust side.

  In addition, the timing of the end of the supply of nitrogen gas is the time when the concentration of nitrogen gas has increased to a level that does not cause an explosion when hydrogen gas is mixed into the aircraft (below the lower explosion limit of hydrogen concentration). It is assumed that the nitrogen gas concentration reaches 95%.

  In the intermediate replacement gas sealing step, whether or not the nitrogen gas concentration has reached a predetermined concentration or more is determined based on the amount of nitrogen gas supplied into the machine. The nitrogen gas supply amount is determined from, for example, a measurement result measured based on the number of nitrogen gas cylinders 35 whose capacity is known in advance or information on a flow sensor that measures the inert gas supply amount of the inert gas supply unit 31. can do.

Further, the gas supply amount (gas consumption amount) required when replacing the gas in the container with another gas and the gas concentration in the container have a relationship represented by the following formula (1). In addition, “ln” shown in Expression (1) is a notation indicating a logarithm (natural logarithm) with the base as the Napier number e (= 2.718...). That is, lnY = log _e Y (Y> 0).

For example, the purity of nitrogen gas sealed in the machine (filled gas purity: Z ₀ ) is 100%, the concentration of nitrogen gas in the machine before gas filling (gas concentration in the container before filling: Z ₁ ) is 0%, after gas filling Assuming that the concentration of nitrogen gas in the machine (gas concentration in the container after encapsulation: Z ₂ ) is 95%, the gas consumption required for substitution into the above-described equation (1) is ln {100 / 100-95}. ≈2.99, about 3 times the internal volume. That is, it can be determined that the nitrogen gas concentration in the machine has reached 95% when the supply of nitrogen gas that is three times the volume of the machine is completed.

  When the supply of nitrogen gas that can be determined to have increased to such an extent that no explosion occurs when hydrogen gas is mixed into the machine, the regulator valve 38 is closed to stop the supply of nitrogen gas. The replacement of air with nitrogen gas, which is an inert gas (intermediate replacement gas), is completed. That is, all processing steps of the intermediate replacement gas sealing process are completed.

  In the intermediate replacement gas sealing step, the nitrogen gas concentration in the machine is determined from the calculation result according to the above formula (1) without using the gas purity meter 56. You may double check the nitrogen gas concentration.

  Further, in the above-described intermediate replacement gas sealing step, the nitrogen gas concentration in the machine reached 95% from the calculation result of the above formula (1) when the supply of nitrogen gas that is three times the volume in the machine was completed. However, it is not always necessary to use a triple amount, and it is sufficient that the amount is at least a triple amount. For example, it may be determined that the nitrogen gas concentration in the machine has reached 95% when the amount reaches 3.1 times with an allowance of about several percent.

  Next, in the hydrogen gas filling step (FIG. 3), first, a discharge port for releasing nitrogen gas, which is the in-machine gas, from the lower pipe 7 to the atmosphere is secured. More specifically, among the regulating valves 18, 21, 22, 25, 38, 41 that are normally closed valves, the regulating valves 41, 22 are opened, and the lower pipe 7 is connected to the pipe 19, the regulating valve 41, the regulating valve 22. And a state connected to the atmosphere via the atmosphere discharge pipe 23 (atmospheric release state).

  Subsequently, the hydrogen gas stored in the hydrogen gas supply unit 11 is supplied to the upper pipe 6. More specifically, the adjustment valve 18 is opened slightly, and the sound of the gas flowing through the pipe 19 is not different from the sound generated at the normal time, whether there is an increase in the in-machine pressure measured by the in-machine pressure gauge 52, and the vicinity of the bearing 3 After confirming that no hydrogen gas leaks from the control valve 18, the regulating valve 18 is further opened.

  The opening degree of the regulating valve 18 is maximized within a range in which the in-machine pressure does not exceed a preset safety limit pressure upper limit value. That is, hydrogen gas is supplied into the machine as quickly as possible. The supply rate of hydrogen gas (supply amount per unit time) is determined according to the exhaust capacity (exhaust amount per unit time) of the atmospheric discharge line 34 on the exhaust side.

  In addition, the timing of the end of the supply of hydrogen gas is the time when the concentration of hydrogen gas reaches a predetermined concentration, for example, 95% of the hydrogen gas concentration in the machine. Whether or not the hydrogen gas concentration has reached a predetermined concentration or more is determined by the amount of hydrogen gas supplied into the apparatus using the above equation (1), as in the above-described intermediate replacement gas sealing step. That is, it is determined that the hydrogen gas concentration in the machine has reached 95% when the supply of hydrogen gas that is three times the volume of the machine is completed.

  The hydrogen gas concentration in the machine can be double checked using the gas purity meter 53. Similarly to the intermediate replacement gas filling step, the timing for determining that the hydrogen gas concentration in the machine has reached 95% does not necessarily have to be three times the volume of the machine, and if it is more than three times the timing. Is optional.

  When the supply of hydrogen gas that can be determined that the concentration of hydrogen gas in the machine has reached a predetermined concentration or more is completed, the adjustment valve 18 is closed to stop the supply of hydrogen gas, and the replacement of nitrogen gas with hydrogen gas is performed. To complete. That is, all the processing steps of the hydrogen gas filling process are completed.

  In the hydrogen gas releasing step (FIG. 4), first, a discharge port for releasing the hydrogen gas, which is the in-machine gas, from the upper pipe 6 into the atmosphere is secured. More specifically, among the regulating valves 18, 21, 22, 25, 38, 41 that are normally closed valves, the regulating valves 21, 22 are opened, and the upper pipe 6 is connected to the pipe 19, the regulating valve 21, the regulating valve 22. And a state connected to the atmosphere via the atmosphere discharge pipe 23 (atmospheric release state).

  Subsequently, nitrogen gas as an inert gas (intermediate replacement gas) stored in the inert gas supply unit 31 is supplied to the lower pipe 7. More specifically, the adjustment valve 38 is opened slightly, and the sound of the gas flowing through the pipe 39 is not different from the sound generated at the normal time, whether there is an increase in the in-machine pressure measured by the in-machine pressure gauge 52, and the vicinity of the bearing 3 After confirming whether hydrogen gas leaks from the control valve 38, the adjustment valve 38 is further opened.

  The opening degree of the regulating valve 38 is maximized within a range where the in-machine pressure does not exceed a preset safety limit pressure upper limit value. That is, nitrogen gas is supplied into the machine as quickly as possible. The supply speed of nitrogen gas (supply amount per unit time) is determined according to the exhaust capacity (exhaust amount per unit time) of the atmospheric discharge line 13 on the exhaust side.

  Also, the timing of the end of the supply of nitrogen gas is the time when the concentration of nitrogen gas increases to such an extent that no explosion occurs when hydrogen gas is mixed in the machine, for example, when the nitrogen gas concentration in the machine reaches 95% And Whether or not the nitrogen gas concentration has reached a predetermined concentration or more is determined by the amount of nitrogen gas supplied into the apparatus using the above equation (1), as in the above-described intermediate replacement gas sealing step. That is, it is determined that the nitrogen gas concentration in the machine has reached 95% when the supply of nitrogen gas that is three times the volume in the machine has been completed.

  When the supply of nitrogen gas that can be determined to have increased to such an extent that no explosion occurs when hydrogen gas is mixed into the machine, the regulator valve 38 is closed to stop the supply of nitrogen gas. The replacement of hydrogen gas with nitrogen gas (hydrogen gas release) is completed. That is, all the processing steps of the hydrogen gas releasing process are completed.

  In the hydrogen gas releasing step, the nitrogen gas concentration in the machine is determined from the calculation result according to the above formula (1) without using the gas purity meter 56. Nitrogen gas concentration may be double checked. Similarly to the intermediate replacement gas filling step, the timing for determining that the nitrogen gas concentration in the machine has reached 95% does not necessarily have to be three times the volume of the machine, and if it is more than three times the timing. Is optional.

  In the intermediate replacement gas releasing step (FIG. 5), as shown in FIG. 5, the sensor 59 of the oximeter 58 is installed in the machine of the rotating electrical machine 1 using the manhole 9 before the start of the intermediate replacement gas releasing step. . Further, the compressed air supply device 29 can be connected to the opening 26a of the air intake pipe 26 to supply compressed dry air into the machine. That is, after the oxygen concentration in the rotating electrical machine 1 can be measured and the compressed air can be supplied into the rotating electrical machine 1, the intermediate replacement gas releasing step is started.

  In the intermediate replacement gas releasing step, first, a discharge port for releasing nitrogen gas, which is the in-machine gas, from the lower pipe 7 into the atmosphere is secured. More specifically, among the regulating valves 18, 21, 22, 25, 38, 41 that are normally closed valves, the regulating valves 41, 22 are opened, and the lower pipe 7 is connected to the pipe 19, the regulating valve 41, the regulating valve 22. And a state connected to the atmosphere via the atmosphere discharge pipe 23 (atmospheric release state).

  Subsequently, air is supplied to the upper pipe 6. More specifically, after slightly opening the adjustment valve 25 and confirming that the sound of the gas flowing through the pipe 19 is not different from the sound generated during normal time and whether there is an increase in the in-machine pressure measured by the in-machine pressure gauge 52 Then, the regulating valve 25 is further opened.

  The opening degree of the regulating valve 25 is maximized within a range in which the in-machine pressure does not exceed a preset safety limit pressure upper limit value. That is, air is supplied into the aircraft as quickly as possible. The air supply speed (supply amount per unit time) is determined according to the exhaust capacity (exhaust amount per unit time) of the atmospheric discharge line 34 on the exhaust side.

  The timing of the end of air supply is, for example, the time when the oxygen concentration in the machine reaches 18% or more. Whether or not the oxygen concentration in the machine has reached 18% or more is determined by the gas supply amount in the same manner as in the intermediate replacement gas filling step, the hydrogen gas filling step, and the hydrogen gas releasing step. If the above formula (1) is used, theoretically, 95% or more of the in-machine gas is replaced with air when the air that is three times the in-machine volume is supplied from the compressed air supply device 29. It can be judged.

  Here, air (atmosphere) is a mixed gas such as nitrogen gas, oxygen gas, and argon gas, and considering that oxygen contained in the atmosphere is about 21%, 95% of the in-flight gas is air. Since it can be said that about 20% of the in-machine gas is oxygen, the oxygen concentration in the machine is 18% or more when the air that is three times the volume of the machine is supplied from the compressed air supply device 29. Judge.

In the above equation (1), the oxygen concentration of the supplied air is k%, the purity of the air sealed in the machine is 100 (Z ₀ = 100)%, and the oxygen concentration in the machine before air filling is 0 (Z ₁ = 0)%, and the oxygen concentration x% in the machine after air filling is approximated, the above equation (1) can be expressed by the following equation (2). You may determine the timing of the completion | finish of air supply using this following formula (2).

  When the air (or oxygen) concentration in the machine has been supplied to the machine, the air that can be determined to have reached the predetermined concentration or more is closed, the adjustment valve 25 is closed, the supply of air is stopped, and the nitrogen gas is replaced with air. Complete. That is, all processing steps of the intermediate replacement gas discharge process are completed.

  In the intermediate replacement gas releasing step, the air concentration (or oxygen concentration) in the machine is determined from the calculation result of the air supply amount based on the above formula (1) or (2) without using a gas purity meter. However, considering the safety of workers during maintenance and inspection, it is better to measure the oxygen concentration with the oxygen concentration meter 58 and confirm that the oxygen concentration in the machine is within the specified range. preferable. The timing at which it is determined that the oxygen concentration in the machine has reached 18% does not necessarily have to be the time when the compressed air supply device 29 has finished supplying air that is three times the volume of the machine, and more than three times the amount. The timing is arbitrary.

  Further, the compressed air supply device 29 shown in FIG. 5 has been described on the assumption that the air supply amount can be measured and the air supply amount can be measured. However, the compressed air supply device 29 has the air supply amount measurement function. If not, install a flow rate sensor that measures the flow rate of the air flowing through the air intake pipe 26, or from the air supply capacity (exhaust amount per unit time) of the compressed air supply device 29 and the operation time. By estimating, even if the compressed air supply device 29 does not have an air supply amount measurement function, the air supply amount can be obtained, and the above-described in-machine gas replacement method for a rotating electrical machine can be applied.

  According to the in-machine gas replacement method of the rotating electrical machine described above, by replacing the in-machine gas by actively stirring the gas in the machine, an amount of gas equivalent to about 3 times the volume of the machine is sent into the machine of the rotating electrical machine 1 at a stretch. Since (replacement) is performed, the in-machine gas can be replaced in a shorter working time as compared with the conventional rotating electric machine in-machine gas replacement method. For example, in the carbon dioxide gas replacement method, which is one of the conventional gas replacement methods for rotating electrical machines, the replacement operation of the in-machine gas of the rotating electrical machine 1 requiring about 4 to 5 hours is performed using the rotating electrical machine gas replacement device 10. The in-machine gas replacement method of the rotating electrical machine 1 can be performed in about 1 to 2 hours.

  In addition, according to the above-described gas replacement method for a rotating electrical machine, the gas is actively stirred in the machine to replace the gas in the machine. Unlike replacement by specific gravity difference such as air and carbon dioxide gas, an intermediate replacement gas can be selected without considering the specific gravity difference with air.

  Furthermore, according to the above-described method for replacing the gas inside the rotating electrical machine, the gas inside the rotating electrical machine 1 can be replaced without using carbon dioxide as the intermediate replacement gas. The in-flight gas can be replaced without releasing the gas into the atmosphere.

  Furthermore, according to the above-described in-machine gas replacement method for a rotating electrical machine, it is possible to perform replacement (replacement) of the in-machine gas by applying at least a part of the conventional rotating electrical machine gas replacement apparatus 10, so that the existing rotation The in-machine gas of the rotating electrical machine 1 can be replaced by applying the electrical machine 1 and the conventional rotating electrical machine in-machine gas replacement device 10 as they are.

  In particular, in the above-described in-machine gas replacement method for a rotating electrical machine, it is not necessary to measure the concentration of the gas scavenged (released) from the interior of the machine or the gas in the machine. , 56 do not function (the gas concentration cannot be measured), the in-machine gas of the rotating electrical machine 1 can be replaced. In other words, even if the gas control panel 45 and the scavenging panel 46 are not operated due to, for example, flooding due to heavy rain, flooding, tsunami, etc., the gas in the machine can be replaced if the flow path is safe. Useful in terms.

  The above-described in-machine gas replacement method for a rotating electrical machine is an example in which at least a part of a conventional rotary electrical machine gas replacement apparatus 10 is applied from the viewpoint of effective use of existing equipment. Assuming the implementation of the in-machine gas replacement method for a rotating electrical machine according to the embodiment, the interior of the rotating electrical machine is more suitable for the implementation of the in-machine gas replacement method for a rotating electrical machine according to the embodiment of the present invention than the in-machine gas replacement apparatus 10 of the present invention. A gas replacement device can be configured.

[Modification]
FIG. 6 is a schematic diagram illustrating a configuration of a rotating electrical machine internal gas replacement device 10A which is an example of the rotating electrical machine internal gas replacement device according to the embodiment of the present invention.

  The rotating electrical machine internal gas replacement device 10A is more suitable for implementing the rotating electrical machine gas replacement method according to the embodiment of the present invention than the conventional rotating electrical machine internal gas replacement device 10, and more specifically, FIG. Are different in that some constituent elements of the gas replacement device 10 in the rotating electrical machine shown in FIG. Therefore, the control unit 65 will be mainly described, and substantially the same components are denoted by the same reference numerals and description thereof is omitted.

  In the rotating electrical machine internal gas replacement device 10A, the control unit 65 permits the in-machine pressure of the rotating electrical machine based on the measurement result of the in-machine pressure received from the pressure transmitter 67 as a pressure measuring unit that measures the in-machine pressure of the rotating electrical machine 1. The opening degree of at least one of the hydrogen gas supply valve 16, the nitrogen gas supply valve 36, and the adjustment valves 18, 21, 22, 25, 38, 41 is adjusted so as to be within the range.

  Further, the control unit 65 calculates the hydrogen consumption based on the pressure (indicated value) of the hydrogen cylinder 15 based on the pressure (indicated value) of the nitrogen cylinder 35 serving as a supply source of nitrogen, which is an example of an inert gas. For example, the air supply amount is monitored based on the flow rate (indicated value) of the flow meter 69 installed in the pipe 26, and the hydrogen gas supply valve 16 and the nitrogen gas supply are determined based on the monitoring result. The opening degree of at least one of the valve 36 and the regulating valves 18, 21, 22, 25, 38, 41 is adjusted so that the hydrogen gas supply line 12, the atmospheric discharge lines 13, 34, the air intake line 14, and the The open / close state of the active gas supply line 33 is switched.

  Here, in the rotating electrical machine internal gas replacement device 10A, in order to make it easy to grasp the hydrogen gas consumption amount and the nitrogen gas consumption amount, a known amount of hydrogen gas and nitrogen gas is prepared in advance that is three times the internal volume or more. Keep it. In this case, it is possible to determine whether or not the desired gas supply amount has been reached based on whether or not the prepared total amount of gas has been consumed without preparing a flow meter or the like.

  The rotating electrical machine internal gas replacement device 10A is different from the rotating electrical machine internal gas replacement device 10 shown in FIG. 1 in that a gas control panel 45 (draft gauge 51, in-machine pressure gauge 52, gas purity meter 53) and scavenging panel 46 (gas The purity meter 56) is omitted. As described above, the configuration of the gas control panel 45 and the scavenging panel 46 is omitted in the in-machine gas replacement method for a rotating electrical machine according to the embodiment of the present invention. This is because the determination is made based on the gas supply amount without using the measuring means.

  In addition, although the control part 65 of the gas replacement apparatus 10A in the rotating electrical machine described above is an example performed based on the flow rate (indicated value) of the flow meter 69 installed in the pipe 26 as an example of monitoring the air supply amount, The air supply amount can also be monitored by this method. When the air supply amount device 29 has a function of measuring the air supply amount, the air supply amount can be monitored based on the air supply amount measured by the air supply amount device 29, or the air of the air supply amount device 29 can be monitored. It is also possible to monitor the air supply amount by monitoring the required operating time determined from the supply capacity (the displacement per unit time) and the required air supply amount.

  As described above, according to the in-machine gas replacement method and the in-machine gas replacement device of the rotating electrical machine according to the embodiment of the present invention, the gas corresponding to about three times the volume of the interior of the rotating electrical machine 1 is sent into the machine of the rotating electrical machine 1 at once. Since the gas is actively agitated to replace (replace) the in-machine gas, the working time can be shortened as compared with the conventional rotary electric machine gas replacement method.

  In addition, in the in-machine gas replacement method and the in-machine gas replacement apparatus for a rotating electrical machine according to the embodiment of the present invention, an intermediate replacement gas can be selected regardless of the difference in specific gravity with air, so carbon dioxide is used as the intermediate replacement gas. Even if not, the in-machine gas of the rotating electrical machine 1 can be replaced. Therefore, the in-flight gas can be replaced without releasing carbon dioxide, which is one of the greenhouse gases, into the atmosphere.

  Furthermore, in the in-machine gas replacement method and the in-machine gas replacement device for a rotating electrical machine according to the embodiment of the present invention, the concentration of the gas scavenged (released) or the in-machine gas is measured from the interior of the machine as in the conventional rotating electrical machine gas replacement method. Therefore, as an example of the gas replacement device for a rotating electrical machine according to the embodiment of the present invention, a gas replacement device for a rotating electrical machine that does not include the gas purity meters 53 and 56 can be configured. That is, it is possible to simplify the configuration of the gas replacement device in the rotating electrical machine as compared with the conventional case.

  In addition, although several embodiment was described in this specification, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, additions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  For example, the gas replacement device 10 in the rotating electrical machine shown in FIG. 1 is an example of the gas replacement device in the rotating electrical machine according to the embodiment of the present invention, and the gas replacement device in the rotating electrical machine according to the embodiment of the present invention is shown in FIG. It is not limited to the apparatus structure shown by these. For example, a rotating electrical machine according to an embodiment of the present invention is a device in which components that are not premised on the use of a scavenging board 46 (gas purity meter 56) or the like are omitted from the gas replacing device 10 in the rotating electrical machine shown in FIG. It can also be configured as an in-machine gas replacement device.

DESCRIPTION OF SYMBOLS 1 ... Rotary electric machine, 2 ... Rotating shaft, 3 ... Bearing, 4 ... Shaft seal part, 6 ... Upper pipe, 7 ... Lower pipe, 9 ... Manhole, 10, DESCRIPTION OF SYMBOLS 10A ... Gas replacement apparatus in a rotary electric machine, 11 ... Hydrogen gas supply part, 12 ... Hydrogen gas supply line, 13 ... Atmospheric discharge line, 14 ... Air intake line, 15 ... Hydrogen gas cylinder, 16 ... hydrogen gas supply valve, 17 ... pressure reducing valve, 18 ... regulating valve, 19 ... piping, 21 ... regulating valve, 22 ... regulating valve, 23 ... Atmospheric discharge pipe, 23a ... opening, 25 ... regulating valve, 26 ... air intake pipe, 26a ... opening, 29 ... compressed air supply device, 31 ... inert gas supply 33, inert gas supply line, 34 ... atmospheric release line, 35 ... nitrogen gas cylinder, 36 ... nitrogen Gas supply valve, 37 ... pressure reducing valve, 38 ... regulating valve, 39 ... piping, 41 ... regulating valve, 43 ... piping, 45 ... gas control panel, 46 ... scavenging Panel: 51 ... Draft gauge, 52 ... In-machine pressure gauge, 53 ... Gas purity meter, 54 ... Air release pipe, 56 ... Gas purity meter, 58 ... Oxygen concentration meter, 59 ... Sensor, 65 ... Control part, 67 ... Pressure transmitter (pressure measurement part), 69 ... Flow meter.

Claims (8)

An inert gas is supplied all at once within the allowable range of the internal pressure of the rotating electrical machine into the lower pipe installed in the lower part of the rotating electrical machine, and is introduced into the rotating electrical machine through a hole formed in the lower pipe. The inert gas and the air present in the rotating electrical machine are agitated in the rotating electrical machine, and the air is passed through a hole formed in an upper pipe installed in the upper part of the rotating electrical machine. A first step of enclosing the inert gas in the machine of the rotating electrical machine by guiding it into the pipe of the upper pipe and releasing it outside the machine;
Hydrogen gas is supplied into the upper pipe at a stretch within the permissible range of the in-machine pressure of the rotating electric machine, and the hydrogen gas guided into the rotating electric machine from the hole of the upper pipe is enclosed in the rotating electric machine. The inert gas is agitated in the rotary electric machine, and the inert gas sealed in the rotary electric machine is introduced from the hole of the lower pipe into the lower pipe and discharged outside the machine. Thus, the second step of enclosing the hydrogen gas in the machine of the rotating electrical machine,
An inert gas is supplied into the lower pipe within an allowable range of the in-machine pressure of the rotating electrical machine, and is introduced into the rotating electrical machine from the hole of the lower pipe and into the rotating electrical machine. The sealed hydrogen gas is agitated in the rotary electric machine, and the hydrogen gas sealed in the rotary electric machine is introduced from the hole of the upper pipe into the pipe of the upper pipe and released outside the machine. Thus, a third step of releasing the hydrogen gas sealed in the rotating electric machine out of the machine, and
Air is supplied into the upper pipe within a permissible range of the in-machine pressure of the rotating electrical machine, and air that is introduced into the rotating electrical machine from the hole in the upper pipe and the air that is enclosed in the rotating electrical machine. Active gas is stirred in the rotating electric machine, and the inert gas sealed in the rotating electric machine is introduced into the lower electric pipe through the hole in the lower pipe, and discharged outside the machine. An in-machine gas replacement method for a rotating electrical machine, comprising at least one of the fourth steps of releasing the inert gas sealed in the rotating electrical machine out of the machine. Said 1st process and said 3rd process are following formulas.

Parameters V ₀ , Z ₀ , Z ₁ , and Z ₂ are respectively the volume of the rotating electrical machine, the purity of the inert gas sealed in the rotating electrical machine, and the rotating electrical machine before the inert gas is sealed. The inert gas concentration greater than or equal to the gas supply amount Q calculated by giving a numerical value as the concentration target value of the inert gas in the rotating electrical machine after the inert gas filling and in the machine 2. The supply of the inert gas is terminated by assuming that the concentration of the inert gas in the rotary electric machine reaches the concentration target value at the time when the gas is supplied. In-machine gas replacement method for rotating electrical machines. The second step has the following formula:

Parameters V ₀ , Z ₀ , Z ₁ , Z ₂ are respectively the volume of the rotating electrical machine, the purity of the hydrogen gas sealed in the rotating electrical machine, and the interior of the rotating electrical machine before the hydrogen gas sealing. When the hydrogen gas is supplied at a gas supply amount Q or more which is calculated by giving a numerical value as the hydrogen gas concentration target value in the rotary electric machine machine after the hydrogen gas is filled in The in-machine gas replacement for a rotating electrical machine according to claim 1 or 2, wherein the supply of the hydrogen gas is terminated assuming that the concentration of the hydrogen gas in the rotating electrical machine has reached the target concentration value. Method. The fourth step has the following formula:

Parameters V ₀ , k, and x are included in the volume of the rotating electrical machine, the target value of the oxygen concentration in the rotating electrical machine after the air sealing, and the air supplied to the rotating electrical machine, respectively. Assuming that the oxygen concentration in the machine of the rotating electrical machine has reached the target value of the oxygen concentration at the time of supplying air with a gas supply amount Q or more calculated by giving a numerical value as a percentage of the concentration of oxygen generated The in-machine gas replacement method for a rotating electrical machine according to any one of claims 1 to 3, wherein the supply of air is terminated. In the first step and the third step, when the purity of the inert gas sealed in the rotary electric machine is 100%, the inert gas is more than three times the volume in the rotary electric machine. 2. The rotating electrical machine according to claim 1, wherein the supply of the inert gas is terminated assuming that the concentration of the inert gas in the rotating electrical machine reaches 95% or more at the time of supplying the inert gas. In-flight gas replacement method. In the second step, when the purity of the hydrogen gas sealed in the rotary electric machine is 100%, the rotary electric machine is supplied when the hydrogen gas is supplied in an amount not less than three times the volume of the rotary electric machine. The in-machine gas replacement method for a rotating electrical machine according to claim 1 or 2, wherein the supply of the hydrogen gas is terminated assuming that the concentration of the hydrogen gas in the machine reaches 95% or more. The fourth step assumes that the oxygen concentration in the rotating electrical machine has reached 18% or more at the time when the air of 3 times or more the volume in the rotating electrical machine is supplied, and the air The in-machine gas replacement method for a rotating electrical machine according to any one of claims 1 to 3, wherein the supply is terminated. It is a flow path that connects an inert gas supply unit that supplies an inert gas and the interior of the rotating electrical machine via a regulating valve, and supplies the inert gas from the inert gas supply unit to the interior of the rotating electrical machine. An inert gas supply line;
A hydrogen gas supply line for supplying the hydrogen gas from the hydrogen gas supply unit to the rotary electric machine, the flow path connecting the hydrogen gas supply part for supplying the hydrogen gas and the rotary electric machine through an adjustment valve. When,
An air discharge line that connects the inside of the rotating electrical machine and the atmosphere via a regulating valve, and releases the gas remaining in the rotating electrical machine to the outside of the machine;
A flow path connecting the inside of the rotating electrical machine and the compressed air supply device via a regulating valve, an air intake line for supplying air from the compressed air supply device,
A gas supply valve of the inert gas supply unit; a regulating valve of the inert gas supply line; a gas supply valve of the hydrogen gas supply unit; a regulating valve of the hydrogen gas supply line; a regulating valve of the atmospheric discharge line; A valve control unit for controlling the opening of each of the inlet line regulating valves,
The valve control unit includes information on the supply amount of the inert gas received from the inert gas supply unit, the supply amount of the hydrogen gas received from the hydrogen gas supply unit, and the supply amount of air received from the compressed air supply device. Based on the gas supply valve of the inert gas supply unit, the adjustment valve of the inert gas supply line, the gas supply valve of the hydrogen gas supply unit, the adjustment valve of the hydrogen gas supply line, the adjustment valve of the atmospheric discharge line And at least one of a regulating valve for the air intake line, and opening / closing control of the hydrogen gas supply line, the atmospheric discharge line, the air intake line, and the inert gas supply line. In-machine gas replacement device.

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