JP2019027385A - Compressed air storage power generation device and method - Google Patents

Abstract

To make power generation possible with a high performance and quickly even when restarting utilization after long term stopping.SOLUTION: A compressed air storage power generation device comprises: a compressor; an accumulator part for storing compressed air; an expander 8 driven by the compressed air from the accumulator part; a dynamo 11 mechanically connected to the expander 8; a first heat exchanger 5 for cooling the compressed air and heating heat medium by heat exchange between the compressed air supplied to the accumulator part from a compressor 4 and the heat medium; a first heat storage part for storing the heat medium heated by the first heat exchanger 5; a second heat exchanger 7 for heating compressed air and cooling heat medium by heat exchange between the compressed air supplied to the expander 8 from the accumulator part and the heat medium supplied from the first heat storage part; a second heat storage part for storing the heat medium cooled by the second heat exchanger 7 and supplying it to the first heat exchanger 5; and a third heat storage part provided separately from the first heat storage part for storing the heat medium having a higher temperature than that of the first heat storage part capable of supplying it to the second heat exchanger 7.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a compressed air storage power generation apparatus and method.

  In power generation using solar energy such as solar power generation and solar thermal power generation, the power generation output fluctuates greatly due to the influence of sunlight on the day. For example, power generation cannot be performed at night, and power generation output greatly decreases on rainy or cloudy days. Furthermore, on days when the generated power is large but demand is low, such as during the Golden Week or during the Bon holiday, it may be required to stop the power generation due to problems in the power system.

  On the other hand, in wind power generation using a windmill, the power generation output greatly fluctuates due to changes in wind direction and wind power on the day. In a power generation facility such as a wind farm that combines multiple windmills, the power generation output of each windmill can be added to smooth out short-term fluctuations in power generation. I can't. In addition, the windmill may have to be stopped on days when strong winds such as passing typhoons or winter storms occur. In addition, there may be a day when light winds do not need to be stored.

  In order to compensate for such an unstable output of renewable energy, a combination with a power storage device is performed. As the power storage device, a chemical secondary battery such as a lithium battery or a NAS battery is generally used. However, a compressed air storage (CAES) technique for storing and regenerating electric power in the form of compressed air is also known.

  As typical known techniques using the CAES technique, there are those disclosed in Patent Documents 1 to 3. In any of Patent Documents 1 to 3, energy storage efficiency is enhanced by recovering heat generated in the compression process by the compressor.

However, in any case, it is assumed that compressed air is stored in a large storage space such as an underground cave by using unnecessary electric power during off-peak hours (the electric power generated by renewable energy does not change significantly). It does not aim to smooth the fluctuating power or stabilize the frequency of the power system as in the case of power generation using renewable energy such as sunlight or wind power. It is not a machine based on the premise that charging and power generation are frequently stopped.
Moreover, when the electric power which should be absorbed with a compressor changes frequently, there is no indication about changing the absorbed electric energy by changing the motive power which drives a compressor. These techniques are based on the premise that a centrifugal compressor / expander is used, and the rotational speed of the compressor / expander cannot be changed frequently for stable operation.

  For this reason, the applicant has proposed the following CASE technology for the purpose of smoothing the power of renewable energy and stabilizing the frequency of the power system.

Patent Document 4 attempts to adjust the flow rate of the heat medium flowing into the heat exchanger (cooler) downstream of the compressor in order to maintain charge / discharge efficiency. In Patent Document 5, a plurality of high-temperature heat medium tanks are provided in order to prevent mixing of a high-temperature heat medium and a low-temperature heat medium. In Patent Document 6, surplus power is passed through a heater to heat the heating medium.
These conventional technologies are effective for smoothing renewable energy and stabilizing the frequency of the power system. However, when the CAES device is shut down and restarted, the heat placed on the upstream side of the generator is used. Since the temperature of the heat medium introduced into the exchanger (heater for preheating) is lowered, there is a problem that the discharge power immediately after the restart is lowered.

  Although the heat medium tank itself can be insulated almost completely by a heat insulating material or the like, the temperature of the heat medium remaining in the flow path, the heat medium pump, the connection pipe, etc. in the heat exchanger is unavoidable. Further, the CASE device is not always stopped with a sufficient amount of the heat medium left in the high-temperature heat medium tank. When the generator is restarted, even if the air is preheated with a preheating heater using these low-temperature heating media, it cannot be heated to a sufficient temperature, and the discharge power is reduced.

  In Patent Documents 4 to 6, in order to prevent a decrease in the amount of power generated at the start of power generation, the heat medium pump is operated to circulate the high temperature heat medium while a sufficient amount of the high temperature heat medium is stored in the high temperature heat medium tank. It is conceivable to generate electricity after that, but it takes several to tens of minutes to start power generation, and the energy stored by wasting the high-temperature heat medium is wasted by the amount of circulation.

JP 2012-97737 A Special table 2013-512410 gazette Special table 2013-536357 gazette JP 2016-2111416 A Japanese Patent Laid-Open No. 2016-211464 JP 2006-121675 A

  It is an object of the present invention to provide a compressed air storage power generation apparatus and method capable of quickly and efficiently generating power even when restarting after a long-term shutdown.

As a means for solving the above problems, the present invention provides:
A compressor for compressing the sucked air;
A pressure accumulator for storing compressed air compressed by the compressor;
An expander driven by compressed air supplied from the pressure accumulator;
A generator mechanically connected to the expander;
A first heat exchanger that cools the compressed air and heats the heat medium by exchanging heat between the compressed air and the heat medium supplied from the compressor to the pressure accumulator;
A first heat storage section for storing a heat medium heated by the first heat exchanger;
Second heat that heats the compressed air and cools the heat medium by exchanging heat between the compressed air supplied from the pressure accumulator to the expander and the heat medium supplied from the first heat accumulator. An exchange,
A second heat storage unit that stores the heat medium cooled by the second heat exchanger and supplies the heat medium to the first heat exchanger;
A third heat storage unit that is provided separately from the first heat storage unit and stores a heat medium having a temperature higher than that of the heat medium stored in the first heat storage unit so as to be supplied to the second heat exchanger;
A compressed air storage power generation device is provided.

  With this configuration, when restarting after the operation is stopped, even when the temperature of the heat medium is lowered, the heat medium having a temperature higher than that of the first heat storage part can be supplied from the third heat storage part to the expander. As a result, it can be operated efficiently immediately after the start of power generation.

  It is preferable that a heat medium flow path that enables supply of a heat medium from the first heat exchanger to the third heat storage unit is provided.

  With this configuration, the heat medium heated by the first heat exchanger can be stored in the third heat storage unit without adding special heating means. Since the 1st heat exchanger is a large sized thing used at the time of charge, a high temperature heat carrier can be secured quickly.

The compressor and the first heat exchanger consist of a plurality of sets,
In the first heat exchanger, it is preferable to further include a selection unit that makes it possible to select any one of the first heat exchangers that supplies a heat medium to the third heat storage unit.

  With this configuration, it is possible to supply and store the heat medium from the specific first heat exchanger to the third heat storage unit as necessary while charging with the compressor.

  The third heat storage unit preferably includes a first heating unit that heats the stored heat medium.

  With this configuration, the heat medium stored in the third heat storage unit can be heated at an arbitrary timing.

  It is preferable that a second heating means capable of heating the passing heat medium is provided in the heat medium flow path.

  With this configuration, even when the compressor is not driven, the heat medium supplied from the second heat storage unit to the third heat storage unit can be heated by the second heating unit.

  The heat medium flow path connected in parallel with the third heat storage unit includes a third heating unit capable of heating the passing heat medium, and the heat medium is between the third heat storage unit and the third heating unit. It is preferable that it can be circulated.

  With this configuration, it is possible to heat the heat medium stored by the separately provided third heating means without adopting a special configuration for the third heat storage unit.

  A heat medium flow path capable of supplying a heat medium from the first heat storage unit to the first heat exchanger, and a heat medium stored in the first heat storage unit or the second heat storage unit, the first heat exchanger. A heat medium flow path that can be supplied to the first heat exchanger, and a selection unit that can select which of the heat medium stored in the first heat storage unit or the second heat storage unit is supplied to the first heat exchanger; Is preferably further provided.

  With this configuration, even if the compressed air obtained by the compressor cannot be sufficiently heated, the high-temperature heat medium is supplied to the first heat exchanger by supplying the heat medium stored in the first heat storage unit to the first heat exchanger. 3 It can supply to a heat storage part.

As a means for solving the above problems, the present invention provides:
The compressor is driven to discharge compressed air, the heat medium is heated by exchanging heat between the compressed air and the heat medium in a first heat exchanger, and the compressed air is stored in the pressure accumulating unit, and the heat Charging operation for storing the medium in the first heat storage unit;
The compressed air stored in the pressure storage tank and the heat medium stored in the first heat storage section are heat-exchanged by a second heat exchanger to heat the compressed air, which is supplied to the expander and driven to generate power. A compressed air storage power generation method that performs power generation operation in which the heat medium is stored in the second heat storage section so that the heat medium can be supplied to the first heat exchanger.
Provided is a compressed air storage power generation method in which a heat medium is supplied to the expander from a third heat storage unit in which a heat medium having a temperature higher than that of the first heat storage unit is stored at the start of the power generation operation.

  According to the present invention, since the third heat storage unit that stores the heat medium having a temperature higher than that of the first heat storage unit so as to be supplied to the second heat exchanger is provided, the operation is stopped for a long period of time. Even when the temperature of the medium is lowered, power generation can be started quickly and efficiently.

It is the schematic of the CASE apparatus which concerns on 1st Embodiment. It is a block diagram of the control apparatus employ | adopted as the CAES apparatus of FIG. It is a flowchart which shows the content of the auxiliary | assistant heating process performed with the control apparatus of FIG. It is a flowchart which shows the content of the auxiliary | assistant heating process performed with the control apparatus of FIG. It is the schematic of the CASE apparatus which concerns on 2nd Embodiment. It is the schematic of the CASE apparatus which concerns on 3rd Embodiment.

  Embodiments according to the present invention will be described below with reference to the accompanying drawings. In addition, the following description is only illustrations essentially and does not intend restrict | limiting this invention, its application thing, or its use. Further, the drawings are schematic, and the ratio of each dimension is different from the actual one.

(First embodiment)
FIG. 1 schematically shows a compressed air energy storage (CAES) power generator 1 according to a first embodiment. The CAES device 1 leveles output fluctuations of a power generator that generates power using renewable energy, etc., and supplies power to the power system, or supplies power to the power system according to fluctuations in power demand at peak and off-peak times. To be consumed and supplied. The CAES power generator 1 can be grasped by dividing it into an air flow path system 2 and a heat medium flow path system 3.

(Air channel system 2)
In the air flow path system 2, a compressor 4, a first heat exchanger 5, a pressure accumulating tank 6, which is an example of a pressure accumulating unit, a second heat exchanger 7, and an expander 8 are arranged in the air flow direction. In order. As for the compressor 4 and the 1st heat exchanger 5, 1 set connected in series is provided in parallel 3 sets. As for the 2nd heat exchanger 7 and the expander 8, 3 sets of 1 set connected in series are provided in parallel. The air flow path system 2 includes air flow paths 9a to 9d. In FIG. 1, the air flow paths 9a to 9d are illustrated by solid lines.

  An electric motor 10 is mechanically connected to the compressor 4. A power generator (not shown) is electrically connected to the electric motor 10 via a power system P. The power generation device generates power using renewable energy such as wind power, sunlight, solar heat, and wave power. However, the power source is not limited to these renewable energies. The electric motor 10 is driven by fluctuating input power from the power generator. By driving the electric motor 10, the outside air is sucked from the suction port of the compressor 4 through the air flow path 9a. The discharge port of each compressor 4 is connected to the individual flow path 9b1 of the air flow path 9b, and is fluidly connected to the inlet of the pressure accumulating tank 6 via the merged common flow path 9b2. A first heat exchanger 5 is provided in each individual flow path 9b1.

  The compressor 4 of this embodiment is a screw type. Since the screw type compressor 4 can control the rotation speed, it can follow the input power that fluctuates irregularly with good responsiveness, and is preferable as a component of the CAES power generator. The compressor 4 may be other than a screw type such as a scroll type, a turbo type, or a reciprocating type.

  The accumulator tank 6 can store compressed air and store it as energy. A common flow path 9 b 2 is connected to the inlet of the accumulator tank 6. The common flow path 9b2 is provided with a valve V1 that can be controlled to open and close. A common flow path 9c1 of the air flow path 9c is connected to the outlet of the pressure accumulation tank 6. The common flow path 9c1 is provided with a valve V2 that can be controlled to open and close. The individual flow paths 9c2 branched from the common flow path 9c1 are fluidly connected to the air supply ports of the expander 8, respectively. Each individual flow path 9c2 is provided with a second heat exchanger 7 respectively.

  A generator 11 is mechanically connected to each expander 8. Each generator 11 is electrically connected to a power system (not shown) and is also electrically connected to a first heater 23 and a second heater 26 described later. The power line between one generator 11 and the remaining two generators 11 is opened and closed by a switch SW. By opening the switch SW, the first heater 23 and the second heater 26 can be supplied with power from only one generator 11. An air passage 9d for exhaust is fluidly connected to the exhaust port of the expander 8.

  The expander 8 of this embodiment is a screw type. The screw-type expander 8 is preferable as a component of the CAES power generator 1 in that the rotation speed can be controlled. The expander 8 may be other than a screw type such as a scroll type, a turbo type, or a reciprocating type.

(Heat medium flow path system 3)
In the heat medium passage system 3, the first heat exchanger 5, the first heat storage tank 12, which is an example of the first heat storage unit, the second heat exchanger 7, and the second heat storage which is an example of the second heat storage unit. The tank 13 is provided in this order toward the flow direction of the heat medium. A third heat storage tank 14 that is an example of a third heat storage unit is connected to the first heat storage tank 12 in parallel.

  The heat medium flow path system 3 includes heat medium flow paths 15a to 15c. In FIG. 1, the heat medium flow paths 15a to 15c are illustrated by dotted lines. The heat medium can be circulated in the heat medium flow paths 15a and 15b by driving the pumps 16A and 16B. Although the kind of heat medium is not specifically limited, For example, a mineral oil type or glycol type heat medium can be used.

  The first heat storage tank 12 and the third heat storage tank 14 have a heat insulating structure.

  The first heat storage tank 12 stores a heat medium that has absorbed heat from the compressed air by the first heat exchanger 5 and has reached a high temperature. The temperature of the heat medium stored in the first heat storage tank 12 is detected by the first temperature detection sensor 17, and the liquid level position of the heat medium is detected by the first liquid level sensor 18.

  The second heat storage tank 13 stores a heat medium that has radiated heat to the compressed air by the second heat exchanger 7 to a low temperature. The temperature of the heat medium stored in the second heat storage tank 13 is detected by the second temperature detection sensor 19, and the liquid level position of the stored heat medium is detected by the second liquid level sensor 20.

  The third heat storage tank 14 is provided in the middle of the heat medium flow path 15 c branched from the common flow path 15 b 1 of the heat medium flow path 15 b extending from the first heat storage tank 12. The capacity of the third heat storage tank 14 is smaller than that of the first heat storage tank 12, and is about 3 to 10 times the total capacity of the heat medium flow region from the first heat storage tank 12 to the expander 8. The temperature of the heat medium stored in the third heat storage tank 14 is detected by the third temperature detection sensor 21, and the liquid level position of the heat medium is detected by the third liquid level sensor 22. The third heat storage tank 14 accommodates a first heater 23 that is a first heating means for heating the stored heat medium. The third heat storage tank 14 is connected to the heat medium passage 15c via the heat insulation joints 24a and 24b on the inlet side and the outlet side. Thereby, heat transfer from the third heat storage tank 14 to the heat medium flow path 15c is prevented. About the 3rd heat storage tank 14, it is desirable to give severe heat insulation compared with the said 1st heat storage tank 12 by vacuum insulation etc. FIG. A valve V3 that can be controlled to open and close is provided on the upstream side of the third heat storage tank 14, which is one end side of the heat medium passage 15c. The heat medium passage 15c is provided with a fourth temperature detection sensor 25 and a second heater 26 as a second heating means on the downstream side of the third heat storage tank 14. The first heater 23 and the second heater 26 can be heated with electric power supplied from the generator 11 or the electric power system. The other end side of the heat medium passage 15c is branched and connected to the inlet side and the outlet side of the first heat exchanger 5, respectively. Valves V4 and V5 are provided in the branched heat medium flow paths 15c1 and 15c2, respectively, so that opening and closing can be controlled. The third heat storage tank 14 stores the heat medium from the first heat storage tank 12 or the second heat storage tank 13.

  Detection signals from the first to fourth temperature detection sensors 17, 19, 21, 25 and the first to third liquid level sensors 18, 20, 22 are input to the control device 21 described later.

  Each first heat exchanger 5 is provided in the middle of an individual flow path 15 a 2 branched from a common flow path 15 a 1 of a heat medium flow path 15 a extending from the second heat storage tank 13. Each individual flow path 15a2 is provided with a valve V6 that can be controlled to open and close until reaching the first heat exchanger 5, and a pump 16A. Each individual flow path 15 a 2 joins the common flow path 15 a 3 and is fluidly connected to the first heat storage tank 12. In the common flow path 15a3, a valve V7 disposed in front of the inlet side of the first heat storage tank 12 and a valve V8 disposed between the first heat exchanger 5A closest to the third heat storage tank 14 are opened and closed. It is provided to be controllable.

  Each of the second heat exchangers 7 is provided in the middle of the individual flow path 15b2 branched from the common flow path 15b1 of the heat medium flow path 15b extending from the first heat storage tank 12. The common flow path 15b1 is provided with a valve V9 that can be controlled to open and close in the vicinity of the outlet side of the first heat storage tank 12. Each individual flow path 15b2 is provided with a valve V10 that can be controlled to open and close until reaching the second heat exchanger 7, and a pump 16B. Each individual flow path 15 b 2 joins the common flow path 15 b 3 and is fluidly connected to the second heat storage tank 13.

(Compressor unit)
The compressor 4, the electric motor 10, the first heat exchanger 5, and the pump 16 </ b> A constitute a compressor unit 19. The compressor unit 19 may include a plurality of compressors 4 and a plurality of first heat exchangers 5. Moreover, the compressor 4 and the 1st heat exchanger 5 can also be comprised by 1 unit | set, respectively.

(Generator unit)
The expander 8, the generator 11, the second heat exchanger 7, and the pump 16 </ b> B constitute a generator unit 20. The generator unit 20 may include a plurality of expanders 8 and a plurality of second heat exchangers 7. Moreover, the expander 8 and the 2nd heat exchanger 7 can also be comprised by one, respectively.

(Control device)
FIG. 2 is a block diagram of the control device 21 employed in the CAES device of FIG. In FIG. 2, the control device 21 is a control constructed by hardware including a storage device such as a CPU (Central Processing Unit), a RAM (Random Access Memory), and a ROM (Read Only Memory), and software installed therein. It is an example of a means. As shown in FIG. 2, the control device 21 uses the pumps 16 </ b> A based on input signals from the first to fourth temperature detection sensors 17, 19, 21, 25, the first to third liquid level sensors 18, 20, 22, and the like. ~ 16C, valves V1 to V9, etc. are driven and controlled.

  Next, the operation of the CAES power generator 1 having the above-described configuration will be described separately for a charge operation and a power generation operation.

(Charging operation)
In the charging operation, the electric motor 10 is driven by the electric power from the power generator, and each compressor 4 is operated. The valves V1, V6 to V8 are opened, and the valves V2, V4, V9 and V10 are closed. Then, the pump 16A is driven. By driving the electric motor 10, outside air is sucked into the compressor 4 and discharged as compressed air. The discharged compressed air passes through the first heat exchanger 5, is heat-exchanged with the heat medium, cooled to substantially the outside air temperature, and then stored in the pressure accumulation tank 6. Further, the heat medium supplied from the second heat storage tank 13 to the first heat exchanger 5 by driving the pump 16A absorbs heat from the compressed air (preferably up to 150 to 200 ° C.), 1 is stored in the heat storage tank 12.

(Power generation operation)
In the power generation operation, the valves V2, V9, and V10 are opened, and the valves V1, V6, and V7 are closed. Then, the pump 16B is driven. By opening the valve V2, the compressed air sent from the pressure accumulating tank 6 is supplied to the air supply port 8a of the expander 8 through the air flow path 9c. Before being supplied to the expander 8, the compressed air passes through the second heat exchanger 7 and is heated by heat exchange with the heat medium from the first heat storage tank 12. The heat medium stored in the first heat storage tank 12 is sufficiently heated by the above-described charging operation. Therefore, the temperature of the compressed air can be sufficiently raised. The sufficiently heated compressed air is supplied into the expander 8 through the air supply port. Thereby, the expander 8 operates and drives the generator 11. The electric power generated by the generator 11 is supplied to the electric power system P. The air expanded by the expander 8 is exhausted from the exhaust port through the air flow path 9d. The heat medium cooled by radiating heat to the compressed air in the second heat exchanger 7 is stored in the second heat storage tank 13.

  By the way, in the CAES apparatus 1, there is no problem while the power generation apparatus operates smoothly and is continuously charged or discharged, but when stopped for a long time, the temperature of the heat medium is lowered. In particular, in the heat medium flow path 15b, the second heat exchanger 7, and the like, the amount of the heat medium is smaller than that of the first heat storage tank 12, and the surface area with respect to the heat medium volume is large, so heat is easily dissipated.

  Therefore, when the CASE device is stopped for a long period of time, in the power generation operation, auxiliary heating processing for increasing the temperature of the heat medium supplied to the expander 8 is executed as follows according to the flowcharts shown in FIGS. 3 and 4.

  First, the capacity of the heat medium in the third heat storage tank 14 (actual heat medium capacity v) is calculated based on the detection signal from the third liquid level sensor 22 (step S1). Subsequently, it is determined whether or not the actual heat medium capacity v is equal to or larger than a preset capacity (set capacity V) (step S2). Here, the set capacity V is, for example, 2 to 3 times the total capacity of the region in which the heat medium flows from the third heat storage tank 14 to the expander 8 in the heat medium flow paths 15b and 15c.

  If the actual heat medium capacity v is equal to or greater than the set capacity V (step S2: YES), the temperature of the heat medium in the third heat storage tank 14 (actual heat medium temperature) based on the detection signal from the third temperature detection sensor 21. t) is read (step S3). Then, it is determined whether or not the actual heat medium temperature is equal to or higher than a preset temperature (set temperature T) (step S4). Here, the set temperature T is set to a value (for example, 150 to 200 ° C.) higher than the temperature of the heat medium in the first heat storage tank 12.

  When the actual heat medium temperature t is equal to or higher than the set temperature T (step S4: YES), the valve V3 is opened (step S5), and the driving of the pump 16B is started (step S6). At this time, the valve V9 is closed to prevent the heat medium from being supplied from the first heat storage tank 12 to the expander 8. The open / close states of the other valves V1, V2, V4 to V8, and V10 are the same as those in the power generation operation. Thereby, the heat medium in the third heat storage tank 14 having a higher temperature than the first heat storage tank 12 can be supplied to the second heat exchanger 7. Therefore, even when the operation is stopped for a long time and the temperature of the heat medium such as the heat medium flow paths 15b and 15c is lowered, the expander 8 is sufficiently heated by the second heat exchanger 7. It becomes possible to start a rapid and highly efficient power generation by supplying a heat medium having a high temperature.

  When the actual heat medium temperature t is lower than the set temperature T (step S4: NO), the valve V3 is closed (step S7), and energization to the first heater 23 in the third heat storage tank 14 is started (step S8). ). Thereby, the heat medium in the 3rd heat storage tank 14 is heated. As a result of heating the heat medium by the first heater 23, if the actual heat medium temperature t is equal to or higher than the set temperature T, the processes of Steps S5 and S6 are executed.

  If the actual heat medium capacity v is less than the set capacity V (step S2: NO), the valve V3 is closed (step S9), and it is determined whether or not the charging operation is being performed (step S10). If the charging operation is in progress, the heat medium passing by the compressed air can be heated by the first heat exchanger 5, so the valve V4 is opened and the valves V5 and V8 are closed (step S11). Then, the pump 16A at the position closest to the third heat storage tank 14 is driven (step S12). As a result, the heat medium supplied from the second heat storage tank 13 is heated by the first heat exchanger 5 and flows into the third heat storage tank 14. If the charging operation is not being performed, the valve V5 is opened and the valves V4 and V8 are closed (step S13). Then, by driving the pump 16A (step S12), the heat medium in the second heat storage tank 13 is caused to flow directly into the third heat storage tank.

  If the actual heat medium capacity v in the third heat storage tank 14 is equal to or greater than the set capacity V, the actual heat medium temperature t is read (step S14), and whether the actual heat medium temperature t is equal to or greater than the set temperature T, as described above. It is determined whether or not (step S15). If the actual heat medium temperature t is equal to or higher than the set temperature T, the valve V3 is opened (step S16) and the driving of the pump 16B is started (step S17), as described above. If the actual heat medium temperature t is lower than the set temperature T, the valve V3 is closed (step S18), and the first heater 23 is energized (step S19). Here, the detected temperature t2 detected by the fourth temperature detection sensor 25 is read (step S20), and the detected temperature t2 is compared with the set temperature T2 (step S21). If the detected temperature t2 is equal to or higher than the set temperature T2, it is determined that the heat medium can be sufficiently heated only by the first heater 23, and the second heater 26 is not energized. On the other hand, if the detected temperature t2 is lower than the set temperature T2, it is determined that the heating medium is insufficiently heated only by the first heater 23, and the second heater 26 is energized (step S22).

  Thus, even if it is a power generation operation when the drive of the CASE power generator 1 is stopped for a long period of time and the temperature of the heat medium is reduced by executing the auxiliary heating process, the third heat storage tank 14 A high-temperature heat medium can be supplied to the second heat exchanger 7 from the beginning, for example, by heating the internal heat medium by the first heater 23. Therefore, the temperature of the compressed air supplied to the expander 8 can be increased to start power generation quickly and with high efficiency.

  The three compressors 4 may be operated to supply the heat medium heated by the first heat exchangers 5 to the third heat storage tank 14, but only one unit may be provided by closing the valve V8. And only the heat medium heated by the corresponding one first heat exchanger 5 may be supplied to the third heat storage tank 14. According to this, even when the charging operation and the power generation operation are performed simultaneously after a long-term operation stop, it is possible to cope with it.

  The second heater 26 is used only when the heating by the first heater 23 is insufficient. However, the heating medium may be heated by the second heater 26 at the same time or only. Similarly, the first heat exchanger 5 may also be configured to heat the heat medium alone or in combination with at least one of the first heater 23 and the second heater 26.

  The heat medium in the third heat storage tank 14 is supplied to all the three second heat exchangers 7, but may be supplied to only one of them. When the generated power required at the time of restart is small, the power generation efficiency can be increased by supplying the heat medium only to any one of the second heat exchangers 7. In this case, it is only necessary to open only one of the valves V10 and close the other.

  Although power may be supplied from all three generators 11 to the first heater 23 and the like, the switch SW may be opened and only one generator 11 may be provided.

(Second Embodiment)
FIG. 5 shows a CASE power generator 1 according to the second embodiment. In this CAES power generator 1, instead of providing the first heater 23 in the third heat storage tank 14, a heat medium flow path 15d is connected in parallel to the third heat storage tank 14, and a pump 16C, A third heater 27 and a valve V11 are provided. A valve V12 is also provided on the heat medium flow path 15c side. Then, when heating the heat medium in the third heat storage tank 14, the valve V12 is closed and the pump 16C is driven. Thereby, the heat medium flows so as to circulate in the heat medium flow path 15d, and the heat medium is heated by the third heater 27 at that time. In addition, since the structure of those other than this is the same as said 1st Embodiment, the code | symbol corresponding to a corresponding member is attached | subjected and the description is abbreviate | omitted.

  According to the second embodiment, the pump 16C, the third heater 27, and the valves V11 and V12 are provided in the middle of the heat medium flow path 15d without requiring any special device in the configuration of the third heat storage tank 14. The structure for heating the heat medium in the 3rd heat storage tank 14 can be obtained only by it.

(Third embodiment)
FIG. 6 shows a CAES power generator 1 according to the third embodiment. In the CASE power generation device 1, a heat medium flow path 15 e that connects the first heat storage tank 12 to the first heat exchanger 5, and a heat medium flow path 15 f that connects the second heat storage tank 13 to the first heat exchanger 5; Is formed. Valves V13 and V14 are respectively provided in the middle of the heat medium flow paths 15e and 15f connected to the common flow path 15a1 from the first heat storage tank 12 and the second heat storage tank 13. Further, the common flow path 15a1 is connected at a position between the first heat storage tank 12 and the third heat storage tank 14 in the middle of the heat medium flow path 15c. In addition, since the structure of those other than this is the same as said 2nd Embodiment, the code | symbol corresponding to a corresponding member is attached | subjected and the description is abbreviate | omitted.

  In the third embodiment, in the normal charging operation, the heating medium is supplied from the second heat storage tank 13 to each first heat exchanger 5 by opening the valve V14 and closing the valve V13. However, when the heat medium cannot be sufficiently heated by the first heat exchanger 5 such as when the outside air temperature sucked into the compressor 4 is low, each of the first heat exchangers is closed by closing the valve V14 and opening the valve V13. 5 is supplied with a heat medium from the first heat storage tank 12. The first heat storage tank 12 stores a heat medium that is sufficiently hotter than the second heat storage tank 13. Therefore, even if the temperature of the passing air is not so high in the first heat exchanger 5, the temperature of the heat medium can be sufficiently increased.

  Thus, according to the third embodiment, when the temperature of the heat medium supplied from the second heat storage tank 13 cannot be sufficiently raised by the first heat exchanger 5, the first heat storage tank in which a higher temperature heat medium is accommodated. 12 can be supplied. Therefore, the heat medium stored in the third heat storage tank 14 can be quickly brought to a desired temperature.

  In addition, this invention is not limited to the structure described in the said embodiment, A various change is possible.

  In the embodiment, the example in which three each of the expander 8 and the compressor 4 are provided has been described, but any one, two, or four or more may be provided. Further, the number of the expander 8 and the compressor 4 is not necessarily the same.

  Furthermore, in the said embodiment, although the compressor 4 and the expander 8 are provided separately, you may integrate as a compressor and expander by reversely rotating a compressor and making it function as an expander.

DESCRIPTION OF SYMBOLS 1 ... CAES apparatus 2 ... Air flow path system 3 ... Heat-medium flow path system 4 ... Compressor 5 ... 1st heat exchanger 6 ... Accumulation tank 7 ... 2nd heat exchanger 8 ... Expander 9 ... Air flow path 10 ... Electric motor 11 ... Generator 12 ... First heat storage tank 13 ... Second heat storage tank 14 ... Third heat storage tank 15 ... Heat medium flow path 16A-16C ... Pump 17 ... First temperature detection sensor 18 ... First liquid level sensor 19 ... 2nd temperature detection sensor 20 ... 2nd liquid level sensor 21 ... 3rd temperature detection sensor 22 ... 3rd liquid level sensor 23 ... 1st heater 24 ... heat insulation joint 25 ... 4th temperature detection sensor 26 ... 2nd heater 27 ... 2nd 3 heaters V1-V14 ... Valve

Claims (8)

A compressor for compressing the sucked air;
A pressure accumulator for storing compressed air compressed by the compressor;
An expander driven by compressed air supplied from the pressure accumulator;
A generator mechanically connected to the expander;
A first heat exchanger that cools the compressed air and heats the heat medium by exchanging heat between the compressed air and the heat medium supplied from the compressor to the pressure accumulator;
A first heat storage section for storing a heat medium heated by the first heat exchanger;
Second heat that heats the compressed air and cools the heat medium by exchanging heat between the compressed air supplied from the pressure accumulator to the expander and the heat medium supplied from the first heat accumulator. An exchange,
A second heat storage unit that stores the heat medium cooled by the second heat exchanger and supplies the heat medium to the first heat exchanger;
A third heat storage unit that is provided separately from the first heat storage unit and stores a heat medium having a temperature higher than that of the heat medium stored in the first heat storage unit so as to be supplied to the second heat exchanger;
A compressed air storage power generator.   The compressed air storage power generation device according to claim 1, further comprising a heat medium flow path capable of supplying a heat medium from the first heat exchanger to the third heat storage unit. The compressor and the first heat exchanger consist of a plurality of sets,
The compressed air storage according to claim 2, further comprising a selection unit that enables selection of any first heat exchanger that supplies a heat medium to the third heat storage unit among the first heat exchangers. Power generation device.   The compressed air storage power generator according to any one of claims 1 to 3, wherein the third heat storage unit includes a first heating unit that heats a stored heat medium.   The compressed-air storage power generator according to claim 2 or 3, further comprising a second heating means capable of heating the passing heat medium in the heat medium flow path.   The heat medium flow path connected in parallel with the third heat storage unit includes a third heating unit capable of heating the passing heat medium, and the heat medium is between the third heat storage unit and the third heating unit. The compressed air storage power generator according to any one of claims 1 to 5, wherein the compressed air storage power generator is configured to be circulated.   A heat medium flow path capable of supplying a heat medium from the first heat storage unit to the first heat exchanger, and a heat medium stored in the first heat storage unit or the second heat storage unit, the first heat exchanger. A heat medium flow path that can be supplied to the first heat exchanger, and a selection unit that can select which of the heat medium stored in the first heat storage unit or the second heat storage unit is supplied to the first heat exchanger; The compressed air storage power generator according to any one of claims 1 to 6, further comprising: The compressor is driven to discharge compressed air, the heat medium is heated by exchanging heat between the compressed air and the heat medium in a first heat exchanger, and the compressed air is stored in the pressure accumulating unit, and the heat Charging operation for storing the medium in the first heat storage unit;
The compressed air stored in the pressure storage tank and the heat medium stored in the first heat storage section are heat-exchanged by a second heat exchanger to heat the compressed air, which is supplied to the expander and driven to generate power. A compressed air storage power generation method that performs power generation operation in which the heat medium is stored in the second heat storage section so that the heat medium can be supplied to the first heat exchanger.
A compressed air storage power generation method for supplying a heat medium to the expander from a third heat storage unit in which a heat medium having a temperature higher than that of the first heat storage unit is stored during the power generation operation.

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