Hydrogen purity maintenance device for rotating electrical machines

Abstract

To provide a hydrogen purity maintenance device for a rotating electric machine that can maintain high hydrogen purity in the rotating electric machine.SOLUTION: A hydrogen purity maintenance device for a rotating electric machine includes two adsorption towers 7 and 12 that are filled with activated carbon molecular sieves 9 and 14 that adsorb and remove impurities contained in the hydrogen inside a rotating electric machine 1, and each of which is connected to the rotating electrical machine 1, first switching portions 16 and 17 that alternately switch the connection between the two adsorption towers 7 and 12 and the rotating electric machine 1, and heating portions 8 and 13 that are installed in the two adsorption towers 7 and 12, respectively, and heat the activated carbon molecular sieves 9 and 14. The heating portion 13 of one adsorption tower 12 connected to the rotating electric machine 1 does not heat the molecular sieve activated carbon 14, and the heating portion 8 of the other adsorption tower 7 heats the molecular sieve activated carbon 9 and releases impurities in the molecular sieve activated carbon 9 to the outside.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present application relates to a hydrogen purity maintaining device for a rotating electrical machine. [Background technology]

[0002] Conventional hydrogen purity maintenance devices for rotating electrical machines connect an adsorption tower composed of a moisture-removing adsorption layer, a carbon dioxide adsorption layer, and an oxygen and nitrogen adsorption layer to the internal gas circulation system of the rotating electrical machine, adsorbing impurities (such as air) and moisture contained in the hydrogen to maintain high hydrogen purity inside the rotating electrical machine. When the adsorbent becomes saturated with impurities, the hydrogen purity inside the rotating electrical machine decreases. Therefore, when the hydrogen purity drops to a certain value, the adsorption tower is separated from the rotating electrical machine and opened to the atmosphere, and hydrogen is then supplied to the adsorption tower from a hydrogen supply device, thereby providing a control device that releases the impurities adsorbed by the adsorbent into the atmosphere (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 61-231849 A (paragraphs 1-4, Figure 1-2) Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional hydrogen purity maintenance devices for rotating electric machines release impurities in hydrogen gas adsorbed on an adsorbent by using the pressure difference (the difference between the pressure inside the rotating electric machine and atmospheric pressure) of pressure swing adsorption (PSA).However, when the pressure inside the rotating electric machine is low, the adsorbed impurities cannot be sufficiently released, making it difficult to maintain the hydrogen purity inside the rotating electric machine.

[0005] The present application discloses a technique for solving the above-mentioned problems, and aims to provide a hydrogen purity maintaining device for a rotating electric machine that can maintain high hydrogen purity within the rotating electric machine. [Means for solving the problem]

[0006] The hydrogen purity maintaining device for a rotating electric machine disclosed in the present application comprises: In a hydrogen purity maintenance device for a rotating electrical machine in which hydrogen is sealed, two adsorption towers filled with activated carbon molecular sieves that adsorb and remove impurities contained in hydrogen inside the rotating electric machine, the two adsorption towers being connected to the rotating electric machine respectively; a first switching unit that alternately switches the connection between the two adsorption towers and the rotating electric machine; a second switching unit that alternately switches the introduction of hydrogen into the two adsorption towers; the second switching unit switches to introduce hydrogen into the other adsorption tower, a third switching unit that alternately switches the introduction of air into the two adsorption towers; the third switching unit switches to introduce air into the other adsorption tower, and when release of impurities from the activated carbon molecular sieve in the other adsorption tower is completed, cuts off the introduction of air into the other adsorption tower; the second switching unit is configured to switch to introduce hydrogen into the other adsorption tower when the introduction of air into the other adsorption tower is blocked, and a heating unit installed in each of the two adsorption towers to heat the activated carbon molecular sieve. the heating unit of one of the adsorption towers connected to the rotating electric machine does not heat the activated carbon molecular sieve; The heating section of the other adsorption tower heats the activated carbon molecular sieve to release impurities in the activated carbon molecular sieve to the outside. [Effects of the Invention]

[0007] According to the hydrogen purity maintaining device for a rotating electrical machine disclosed in the present application, The hydrogen purity inside the rotating electrical machine can be maintained at a high level. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a system diagram showing the configuration of a hydrogen purity maintaining device for a rotating electric machine according to a first embodiment. [Figure 2] FIG. 10 is a system diagram showing the configuration of a hydrogen purity maintaining device for a rotating electric machine according to a second embodiment. [Figure 3]FIG. 10 is a system diagram showing the configuration of a hydrogen purity maintaining device for a rotating electric machine according to a second embodiment. [Figure 4] FIG. 11 is a system diagram showing the configuration of a hydrogen purity maintaining device for a rotating electric machine according to a third embodiment. [Figure 5] 5 is a block diagram showing the configuration of a control device for the hydrogen purity maintenance device for the rotating electric machine shown in FIG. 4. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiment 1 FIG. 1 is a system diagram showing the configuration of a hydrogen purity maintainer for a rotating electric machine according to a first embodiment. The present application relates to a hydrogen purity maintainer for a rotating electric machine (hereinafter referred to as the maintainer) 6 for maintaining the purity of hydrogen gas in a rotating electric machine 1 in which hydrogen gas is sealed. In the diagram, the rotating electric machine 1 has a rotating shaft 2 and a sealer 3 for sealing hydrogen gas therein. The rotating electric machine 1 and the maintainer 6 are connected by a connection pipe 4 that outputs hydrogen gas from the rotating electric machine 1 to the maintainer 6 and a connection pipe 11 that introduces hydrogen gas from the maintainer 6 to the rotating electric machine 1. An inlet-side isolation valve 5 is connected to the connection pipe 4, and an outlet-side isolation valve 10 is connected to the connection pipe 11. The inlet-side isolation valve 5 and the outlet-side isolation valve 10 can isolate or connect the maintainer 6 from the rotating electric machine 1.

[0010] The maintenance device 6 has a two-tower structure and includes an adsorption tower 7 and an adsorption tower 12. Each of the adsorption towers 7 and 12 is filled with carbon molecular sieve (CMS) activated carbon (hereinafter referred to as activated carbon) 9 and 14. The activated carbons 9 and 14 are used for pressure swing adsorption (hereinafter referred to as PSA).

[0011] The adsorption towers 7, 12 are also equipped with heaters 8, 13, for example, as heating units for heating the activated carbons 9, 14. The adsorption towers 7, 12 are connected to a discharge pipe 15 for venting to the atmosphere via a three-way discharge valve 18. The adsorption towers 7, 12 are connected to the rotating electric machine 1 via an inlet three-way valve 16 and an outlet three-way valve 17. The adsorption towers 7, 12 are connected to a hydrogen gas supply device 21 via a supply main valve 24 and a first supply three-way valve 19. The hydrogen gas supply device 21 is connected to the adsorption towers 7, 12 from a hydrogen gas cylinder 20 via a pressure adjustment valve 22 and a supply pipe 23.

[0012] Therefore, in the first embodiment, the first switching unit that alternately switches the connection between the two adsorption towers 7, 12 and the rotating electric machine 1 corresponds to the inlet three-way valve 16 and the outlet three-way valve 17. The second switching unit that alternately switches the introduction of hydrogen into the two adsorption towers 7, 12 corresponds to the first supply three-way valve 19 and the supply source valve 24. In the figure, the parts indicated by "S" are switches for switching the valves, and as this applies to the following embodiments as well, the description thereof will be omitted where appropriate.

[0013] Next, the operation of the maintenance device 6 of the first embodiment configured as described above will be described. The hydrogen gas inside the rotating electric machine 1 is sealed inside the rotating electric machine 1 by supplying pressurized sealing oil to the sealing device 3. When air and moisture dissolved in the sealing oil are released into the rotating electric machine 1, the purity of the hydrogen gas inside the rotating electric machine 1 decreases.

[0014] In conventional maintenance devices, an adsorption tower consisting of a moisture-removing adsorption layer, a carbon dioxide adsorption layer, and an oxygen and nitrogen adsorption layer is connected to a rotating electric machine to adsorb impurities such as air other than hydrogen and moisture, thereby maintaining high hydrogen purity inside the rotating electric machine.However, when the adsorption tower becomes saturated with impurities, it is necessary to disconnect the adsorption tower from the rotating electric machine and open it to the atmosphere, and then supply hydrogen from a hydrogen supply device to the adsorption tower to release the impurities.

[0015] Furthermore, in conventional maintenance devices, PSA releases impurities from the adsorbent in the adsorption tower into the atmosphere. When the internal pressure of the rotating electric machine (hydrogen gas pressure) is low, the pressure difference with atmospheric pressure is small, and the adsorbed impurities cannot be sufficiently released. As a result, a large amount of adsorbent is required to maintain high hydrogen purity inside the rotating electric machine, and the capacity of the adsorption tower must be increased.

[0016] In contrast, in the maintenance device 6 of the first embodiment, first, the inlet three-way valve 16 and the outlet three-way valve 17 are switched to connect one of the adsorption towers 12 to the rotating electric machine 1. Then, hydrogen gas containing impurities from the rotating electric machine 1 passes through the connecting pipe 4, the inlet isolation valve 5, and the inlet three-way valve 16, and is introduced into the adsorption tower 12. The adsorption tower 12 then introduces the impurity-containing hydrogen gas, removes the impurities with activated carbon 14, and outputs the hydrogen gas from which the impurities have been removed. The hydrogen gas is then returned to the rotating electric machine 1 via the outlet three-way valve 17, the outlet isolation valve 10, and the connecting pipe 11.

[0017] At this time, the other adsorption tower 7 is disconnected from the rotating electric machine 1 by the inlet three-way valve 16 and the outlet three-way valve 17. The activated carbon 9 in the other adsorption tower 7 is heated by the heater 8. The temperature to which the activated carbon 9 is heated is set in advance depending on the material of the activated carbon 9, the amount of the activated carbon 9, etc. As a result of the heating, impurities in the activated carbon 9 are released to the outside from the release pipe 15 via the release three-way valve 18. Naturally, some impurities in the activated carbon 9 are released to the outside by the PSA.

[0018] Furthermore, at this time, hydrogen gas is introduced from outside into the other adsorption tower 7. Specifically, hydrogen gas is introduced into the other adsorption tower 7 from hydrogen gas cylinder 20 via pressure adjustment valve 22 of hydrogen gas supply device 21, supply piping 23, supply source valve 24, and first supply three-way valve 19. Therefore, impurities in activated carbon 9 in the other adsorption tower 7 are released together with the hydrogen gas from release pipe 15 via release three-way valve 18. This prevents re-adsorption of residual air in the maintenance device 6 due to the release of impurities from activated carbon 9. At this time, hydrogen gas is not introduced into one adsorption tower 12 by the supply source valve 24 and first supply three-way valve 19.

[0019] In the above description, "one adsorption tower" connected to the rotating electric machine 1 is described as adsorption tower 12, and "the other adsorption tower" not connected to the rotating electric machine 1 is described as adsorption tower 7. However, by switching the valves, the same operations as those described above can be performed even in a case where "one adsorption tower" connected to the rotating electric machine 1 is used as adsorption tower 7 to remove impurities from hydrogen gas inside the rotating electric machine 1 with activated carbon 9, and "the other adsorption tower" not connected to the rotating electric machine 1 is used as adsorption tower 12 to heat activated carbon 14 with heater 13 and release the impurities adsorbed to activated carbon 14 to the outside. This also applies to the following embodiments, and therefore description thereof will be omitted as appropriate.

[0020] According to the hydrogen purity maintenance device for a rotating electric machine of the first embodiment configured as described above, In a hydrogen purity maintenance device for a rotating electrical machine in which hydrogen is sealed, two adsorption towers filled with activated carbon molecular sieves that adsorb and remove impurities contained in hydrogen inside the rotating electric machine, the two adsorption towers being connected to the rotating electric machine respectively; a first switching unit that alternately switches the connection between the two adsorption towers and the rotating electric machine; and a heating unit installed in each of the two adsorption towers to heat the activated carbon molecular sieve. the heating unit of one of the adsorption towers connected to the rotating electric machine does not heat the activated carbon molecular sieve; The heating unit of the other adsorption tower heats the activated carbon molecular sieve to release impurities in the activated carbon molecular sieve to the outside. Regardless of the difference between the internal pressure of the rotating electric machine and atmospheric pressure, even if the pressure difference required for PSA cannot be obtained sufficiently, impurities in the activated carbon can be released by heating the heating section, so the hydrogen purity inside the rotating electric machine can be maintained at a high level. Furthermore, since impurities in the activated carbon can be released by heating the heating section without being affected by the difference between the internal pressure of the rotating electric machine and atmospheric pressure, the amount of activated carbon required to be filled is small, making it possible to reduce the cost of the hydrogen purity maintenance device for the rotating electric machine. Furthermore, since the rotating electric machine and one of the adsorption towers are connected while impurities are being released from the activated carbon in the other adsorption tower, the hydrogen purity inside the rotating electric machine can be maintained even while impurities are being released from the other adsorption tower.

[0021] Furthermore, according to the hydrogen purity maintenance device for a rotating electric machine of the first embodiment configured as described above, a second switching unit that alternately switches the introduction of hydrogen into the two adsorption towers; The second switching unit switches to introduce hydrogen into the other adsorption tower, Since the hydrogen purity maintenance device for a rotating electric machine can be blown out using only hydrogen, it is possible to prevent impurities from being re-adsorbed into the hydrogen purity maintenance device for a rotating electric machine from remaining air in the maintenance device, for example, in the adsorption tower and piping.

[0022] Embodiment 2 In the above-described first embodiment, hydrogen gas is constantly supplied from the hydrogen gas cylinder 20 when impurities are released from the activated carbons 9 and 14, resulting in a large amount of hydrogen gas consumed during this process. The second embodiment is intended to reduce the amount of hydrogen gas consumed.

[0023] 2 and 3 are system diagrams showing the configuration of a maintenance device according to the second embodiment. FIG. 2 shows a state in which air is introduced into the maintenance device 6, and FIG. 3 shows a state in which hydrogen gas is introduced into the maintenance device 6. In the figures, parts similar to those in the first embodiment are designated by the same reference numerals, and their explanations are omitted. The maintenance device 6 includes a second three-way supply valve 26 that switches between air introduced from a compressor 25 and hydrogen gas. Therefore, in the second embodiment, the first three-way supply valve 19, the second three-way supply valve 26, and the supply source valve 24 correspond to a second switching unit that alternately switches the introduction of hydrogen into the two adsorption towers 7 and 12. Furthermore, the first three-way supply valve 19, the second three-way supply valve 26, and the supply source valve 24 correspond to a third switching unit that alternately switches the introduction of air into the two adsorption towers 7 and 12.

[0024] First, as shown in Fig. 2, similarly to the first embodiment, when the activated carbon 9 in the other adsorption tower 7 starts to release impurities, the second three-way supply valve 26 is operated to operate the compressor 25 and continuously send air into the activated carbon 9 in the other adsorption tower 7. At the same time, the heater 8 heats the activated carbon 9 in the other adsorption tower 7, and the adsorbed impurities are released into the atmosphere via the release pipe 15.

[0025] Next, when the release of impurities is complete, compressor 25 is stopped, second three-way supply valve 26 is switched as shown in Figure 3, and hydrogen gas is supplied from hydrogen gas cylinder 20 to activated carbon 9 in the other adsorption tower 7, as in the first embodiment. However, "completion of impurity release" here refers to the completion of impurity release while air is flowing, and impurities will be further released by hydrogen gas introduced thereafter. This prevents air remaining in the other adsorption tower 7 or piping from being re-adsorbed in maintenance device 6, and further reduces the amount of hydrogen gas consumed when releasing impurities, thereby reducing the cost of maintenance device 6.

[0026] According to the hydrogen purity maintenance device for a rotating electric machine of the second embodiment configured as described above, In addition to providing the same effects as those of the first embodiment, a third switching unit that alternately switches the introduction of air into the two adsorption towers; the third switching unit switches to introduce air into the other adsorption tower, and when release of impurities from the activated carbon molecular sieve in the other adsorption tower is completed, cuts off the introduction of air into the other adsorption tower; When the introduction of air into the other adsorption tower is blocked, the second switching unit switches to introduce hydrogen into the other adsorption tower, Air can be introduced into the adsorption tower when heating the activated carbon, and hydrogen can be introduced after the impurities have been released, preventing impurities remaining in the adsorption tower from being re-adsorbed into the hydrogen purity maintenance device of the rotating electrical machine, which would otherwise reduce the adsorption capacity of the activated carbon. Furthermore, the amount of hydrogen consumed can be reduced when the activated carbon releases impurities, and the cost of the hydrogen purity maintaining device for the rotating electrical machine can be reduced.

[0027] Embodiment 3 FIG. 4 is a system diagram showing the configuration of a maintenance device according to a third embodiment. FIG. 5 is a block diagram showing the configuration of a control device for the maintenance device shown in FIG. 4. In the figure, parts similar to those in the above-described embodiments are designated by the same reference numerals, and their description will be omitted. As shown in FIG. 4, a control device 27 of the maintenance device 6 is connected to the inlet three-way valve 16, the outlet three-way valve 17, the first supply three-way valve 19, the release three-way valve 18, the heater 8, and the heater 13 via a cable 28. The control device 27 switches the inlet three-way valve 16, the outlet three-way valve 17, the first supply three-way valve 19, and the release three-way valve 18, and turns the heater 8 and the heater 13 on and off, as shown in the above-described embodiments, by using a timer for time management. This time management can be set in advance based on the specifications and operating state of the rotating electric machine 1, the material and amount of the activated carbon 9 and 14 in each adsorption tower 7 and 12, and the like.

[0028] An example of hardware for the control device 27 is shown in FIG. 5. In the figure, the control device 27 is composed of a processor 100 and a storage device 101. Although the storage device is not shown, it includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory. Alternatively, an auxiliary storage device such as a hard disk may be provided instead of the flash memory. The processor 100 executes a program input from the storage device 101. In this case, the program is input to the processor 100 from the auxiliary storage device via the volatile storage device. The processor 100 may output data such as calculation results to the volatile storage device of the storage device 101, or may store the data in the auxiliary storage device via the volatile storage device.

[0029] According to the hydrogen purity maintenance device for a rotating electric machine of the first embodiment configured as described above, The same effects as those of the above embodiments can be achieved, and A control device is provided that controls the switching of each of the switching units and the on / off of the heating units over time. The hydrogen purity maintenance device for rotating electrical machines does not require costly equipment such as purity monitoring instruments and control logic for valve operation based on hydrogen purity monitoring, and can be managed using time management alone, making it possible to reduce the cost of the hydrogen purity maintenance device for rotating electrical machines.

[0030] Although the present application describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are conceivable within the scope of the technology disclosed in this application, including, for example, cases where at least one component is modified, added, or omitted, and cases where at least one component is extracted and combined with a component of another embodiment. [Explanation of symbols]

[0031] 1 rotating electric machine, 2 rotating shaft, 3 sealer, 4 connecting piping, 5 inlet isolation valve, 6 maintenance device, 7 adsorption tower, 8 heater, 9 activated carbon, 10 outlet isolation valve, 11 connecting pipe, 12 adsorption tower, 13 heater, 15 discharge pipe, 16 inlet side three-way valve, 17 outlet side three-way valve, 18 discharge three-way valve, 19 first supply three-way valve, 20 Hydrogen gas cylinder, 21 Hydrogen gas supply device, 22 Pressure regulating valve, 23 Supply piping, 24 Supply source valve, 25 Compressor, 26 Second supply three-way valve, 27 Control device, 28 cables.

Claims

1. In a hydrogen purity maintenance device for a rotating electrical machine in which hydrogen is sealed, two adsorption towers filled with activated carbon molecular sieves that adsorb and remove impurities contained in hydrogen inside the rotating electric machine, the two adsorption towers being connected to the rotating electric machine respectively; a first switching unit that alternately switches the connection between the two adsorption towers and the rotating electric machine; a second switching unit that alternately switches the introduction of hydrogen into the two adsorption towers; the second switching unit switches to introduce hydrogen into the other adsorption tower, a third switching unit that alternately switches the introduction of air into the two adsorption towers; the third switching unit switches to introduce air into the other adsorption tower, and when release of impurities from the activated carbon molecular sieve in the other adsorption tower is completed, blocks the introduction of air into the other adsorption tower; the second switching unit is configured to switch to introduce hydrogen into the other adsorption tower when the introduction of air into the other adsorption tower is blocked, a heating unit installed in each of the two adsorption towers to heat the activated carbon molecular sieve; the heating unit of one of the adsorption towers connected to the rotating electric machine does not heat the activated carbon molecular sieve; The heating section of the other adsorption tower heats the activated carbon molecular sieve to release impurities in the activated carbon molecular sieve to the outside.

2. 2. The hydrogen purity maintaining device for a rotating electrical machine according to claim 1, further comprising a control device that controls the switching of each of the switching units and the on / off of the heating unit based on time.

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