Power transfer equipment and power transfer method

Abstract

In compressed air energy storage (CAES) technology, while conventional equipment appropriately fulfills its conventional role, it is possible to appropriately supply electricity from the storage location to the power demand destination even when transmission equipment from the storage location to the power demand destination cannot be secured using the conventional equipment, and the stored pressure energy is appropriately supplied in accordance with energy demand. [Solution] The control device S performs transfer power input control, which sets the first switching valve K1 to a bypass distribution state, sets the on-off valve V1 to a closed open state, drives the compressor C to accumulate pressure in the first bypass pipe H2 and sets the expansion turbine ET to a non-rotating state, and transfer power output control, which sets the on-off valve V1 to an open open state to release the gas pressure accumulated in the first bypass pipe H2 and sets the expansion turbine ET to a rotating state.

Description

Technical Field

[0005] , , ,

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[0001] The present invention relates to a power transfer facility and a power transfer method, comprising a main gas pipe through which gas supplied from an upstream side can flow, and a first bypass pipe through which gas can flow in a form of bypassing the main gas pipe when an abnormality occurs in the main gas pipe.

Background Art

[0002] Conventionally, as shown in Patent Documents 1 and 2, a compressor is operated by power supplied from a renewable energy supply facility such as a solar panel or a power supply source such as a commercial power system, and compressed air is stored in a pressure storage container to store power. At the same time, when the compressed air is released from the pressure storage container, a turbine is rotated by the compressed air to drive a generator, and a technology for discharging power in this form, a compressed air energy storage technology (CAES), is known. Incidentally, in the compressed air energy storage technology (CAES) in Patent Document 1, the power generated by wind power generation is used as a power for leveling.

[0003] The above-described compressed air energy storage technology (CAES) has an advantage that it is easier to lengthen the storage time compared to secondary batteries such as lithium ion batteries, and since the storage capacity can be relatively easily increased, it is a technology that can be effectively applied to large-scale power storage facilities.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In locations where facilities using the aforementioned compressed air energy storage (CAES) technology are introduced, it may not be possible to install power transmission equipment to transmit electricity from the point of storage in the accumulator to the power consumer due to technical or economic reasons. Therefore, there has been a need for the development of new technologies to transfer electricity to power consumers even in such cases. Furthermore, there was a need for the development of technology that could appropriately supply the stored pressure energy in a manner that matched energy demand.

[0007] The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a power transfer device and a power transfer method that, in compressed air energy storage technology (CAES), can appropriately perform the conventional role of conventional equipment, and that can appropriately supply power from the pressure storage location to the power demand destination even when power transmission equipment from the pressure storage location to the power demand destination cannot be secured using the conventional equipment, and that can appropriately supply the stored pressure energy in accordance with the energy demand. [Means for solving the problem]

[0008] The power transfer equipment for achieving the above objectives is: A power transfer facility comprising a main gas pipeline through which gas supplied from the upstream side can flow, and a first bypass pipeline through which gas can flow in a manner that bypasses the main gas pipeline in the event of an abnormality in the main gas pipeline, the characteristic configuration of which is: A first switching valve capable of switching the distribution state of gas supplied from the upstream side between a main distribution state, in which the gas is distributed to the main gas pipe, and a bypass distribution state, in which the gas is distributed to the first bypass pipe. At the inlet of the downstream connection between the first bypass piping and the main gas piping, an on / off valve is provided that can switch the opening state of the first bypass piping between a closed opening state including a fully closed state and an open opening state including a fully open state. An expansion turbine is provided between the outlet of the on / off valve of the first bypass piping and the downstream connection portion, and causes the gas stored in the first bypass piping to flow through and expand; A generator that generates electricity using the shaft output of the expansion turbine, A compressor located downstream of the first switching valve in the first bypass piping, which pressurizes the gas being led to the first bypass piping, The system includes a control device that controls the distribution state of the first switching valve, the opening state of the on / off valve, and the drive of the compressor, The control device performs the following: transfer power input control, which sets the first switching valve to the bypass distribution state, sets the on-off valve to the closed open state, drives the compressor to accumulate pressure in the first bypass piping and puts the expansion turbine into a non-rotating state; and transfer power output control, which sets the on-off valve to the open open state and releases the gas pressure accumulated in the first bypass piping to put the expansion turbine into a rotating state. The key feature is that the piping between the compressor and the expansion turbine in the first bypass piping acts as an electricity transfer gas pipe for transferring electricity.

[0009] A power transfer method to achieve the above objective is: The system includes a main gas pipe through which gas supplied from the upstream side can pass, and a first bypass pipe through which gas can pass in a manner that bypasses the main gas pipe in the event of an abnormality in the main gas pipe. A first switching valve capable of switching the distribution state of gas supplied from the upstream side between a main distribution state, in which the gas is distributed to the main gas pipe, and a bypass distribution state, in which the gas is distributed to the first bypass pipe. At the inlet of the downstream connection between the first bypass piping and the main gas piping, an on / off valve is provided that can switch the opening state of the first bypass piping between a closed opening state including a fully closed state and an open opening state including a fully open state. An expansion turbine is provided between the outlet of the on / off valve of the first bypass piping and the downstream connection portion, and causes the gas stored in the first bypass piping to flow through and expand; A generator that generates electricity using the shaft output of the expansion turbine, A power transfer method in a power transfer facility comprising a compressor that increases the pressure of the gas led to the first bypass piping downstream of the first switching valve in the first bypass piping, wherein the characteristic configuration is: The key features are the execution of a transfer power input control that sets the first switching valve to the bypass distribution state, the on-off valve to the closed open state, drives the compressor to accumulate gas pressure in the first bypass piping and puts the expansion turbine into a non-rotating state, and a transfer power output control that sets the on-off valve to the open open state and releases the gas pressure accumulated in the first bypass piping to put the expansion turbine into a rotating state.

[0010] According to the above-described configuration, the first bypass pipe, which is not used in normal conditions when there is no abnormality in the main gas piping, is used as a pressure accumulator. Pressure is accumulated by a compressor on the upstream side of the pressure accumulator and released by an expansion turbine on the downstream side. In this configuration, power can be input via the compressor on the upstream side of the pressure accumulator and output via the expansion turbine on the downstream side. In other words, this technology allows power to be transferred from the upstream side to the downstream side of the pressure accumulator without laying power transmission lines. Furthermore, according to the technology described above, the pressure energy of gas that was previously wasted can be stored and released as needed. During storage, high-pressure gas (for example, relatively high-pressure primary gas supplied from a gas supply facility) is stored, and during release, high-pressure gas is supplied to the expansion turbine and discharged. This not only converts the pressure energy of gas into electrical energy and supplies it, but also enables the supply of electrical energy in accordance with electricity demand. Incidentally, if power input control is not being performed, gas from the upstream side can be guided downstream through the main gas piping, thus ensuring a proper supply of gas to downstream gas consumers. Furthermore, even when power input control is being performed, if power output control is also being performed, when the gas pressure at the outlet of the expansion turbine is above the set pressure, gas can be guided downstream through the first bypass piping, thus ensuring a proper supply of gas to downstream gas consumers. Based on the above, in compressed air energy storage (CAES) technology, it is possible to effectively utilize conventional equipment and appropriately fulfill the conventional roles of said equipment, while also enabling the appropriate supply of electricity from the storage location to the electricity demand destination even when transmission equipment from the storage location to the electricity demand destination cannot be secured. Furthermore, it is possible to realize power transfer equipment and power transfer methods that can appropriately supply the stored pressure energy in accordance with energy demand.

[0011] Further characteristic features of the power transfer equipment are: The aforementioned expansion turbine is a shaft-levitation type expansion turbine in which the rotating shaft is levitated from the bearing by magnetic force, The first bypass piping is equipped with a cold energy recovery heat exchanger at the outlet of the expansion turbine, which is capable of recovering the cold energy contained in the gas expanded by the expansion turbine.

[0012] According to the above-described configuration, firstly, by providing a shaft-levitation type expansion turbine in which the rotating shaft is levitated from the bearing by magnetic force, even when expanding a relatively low-temperature gas, and even when the temperature drops due to the cold generated during expansion, the rotating shaft can be rotated appropriately and used for power generation. This reduces the energy required to preheat the gas before expansion in the expansion turbine, and allows the cold energy of the gas after expansion in the expansion turbine to be recovered by a cold energy recovery heat exchanger located downstream of the expansion turbine. As a result, it is possible to supply cooling to power loads such as data centers that utilize the electricity transferred by the power transfer equipment and require cooling in conjunction with electricity usage. In other words, in locations where gas pipelines exist but the installation of power lines is difficult for economic reasons, etc., it is assumed that the supply of cooling and heating will also be difficult. However, in such locations, both electricity and cooling can be supplied effectively without the need to install power lines or new heat transfer fluid pipelines.

[0013] Further characteristic features of the power transfer equipment are: The first bypass piping is provided with a second bypass piping that bypasses the compressor, and a second switching valve is provided that can switch between a first flow state in which gas flows through the first bypass piping but not through the second bypass piping, and a second flow state in which gas does not flow through the first bypass piping but flows through the second bypass piping. The control device is configured to perform a determination process capable of determining whether the main gas piping downstream of the upstream connection point between the main gas piping and the first bypass piping is in an abnormal state. The control device, when it determines in the determination process that the main gas piping is in the abnormal state, switches the first switching valve to the bypass distribution state, switches the second switching valve to the second flow state, and switches the on / off valve to the open state, regardless of whether it is performing the transfer power input control or the transfer power output control.

[0014] According to the above characteristic configuration, even when an abnormality such as gas leakage occurs in the main gas pipe due to an earthquake or the like, the control device can continue to supply gas stably to the gas consumers on the downstream side of the main gas pipe by switching the first switching valve to the bypass distribution state, switching the second switching valve to the second flow-through state, and switching the on-off valve to the open state, regardless of whether the control device is executing either the transfer power input control or the transfer power output control.

[0015] A further characteristic configuration of the power transfer facility is a pressure regulating device for regulating the secondary-side pressure of the main gas pipe to a set pressure is provided downstream of the downstream-side connection portion in the main gas pipe, and the control device executes the transfer power input control and the transfer power output control so as to maintain the primary-side pressure of the pressure regulating device at or above the set pressure.

[0016] As described above, when the transfer power input control for accumulating gas from the upstream side in the first bypass pipe is executed, the pressure on the upstream side (primary side) of the pressure regulating device may be lower than the set pressure to be set on the downstream side (secondary side). In this case, there may be a shortage of the supply pressure of the gas supplied to the consumers on the downstream side (secondary side), and it may not be possible to maintain an appropriate gas supply. According to the above characteristic configuration, since the control device executes the transfer power input control and the transfer power output control so as to maintain the primary-side pressure of the pressure regulating device at or above the set pressure, it is possible to appropriately switch between the state of executing the transfer power input control and the transfer power output control and the state of stopping, and while realizing the transfer of power, appropriately realize the stable supply of gas to the consumers on the downstream side (secondary side). For example, during late-night hours when the gas usage amount on the downstream side of the pressure regulating device is relatively small, the transfer power input control and the transfer power output control are actively executed, and during daytime hours when the gas usage amount on the downstream side of the pressure regulating device is relatively large, the transfer power input control and the transfer power output control are suppressed (stopped), thereby realizing both the transfer of power and the stable gas supply to the downstream side (secondary side). Furthermore, even during periods when gas usage on the downstream (secondary) side is low, if the secondary pressure of the pressure regulating device is lower than the set pressure, the control device will stop the transfer power input control and transfer power output control, and will also execute control to increase the secondary pressure by allowing gas to flow through the main gas piping.

[0017] Further characteristic features of the power transfer equipment are: The power load supplied with power from the generator is configured to also be able to receive power from the power grid in the area where the first bypass piping is laid. The control device is configured to receive whether the power demand in the power grid in the area where the first bypass piping is laid is below a predetermined power demand lower threshold, The control device, upon receiving notification that the power demand in the power grid is below the lower limit threshold for power demand, at least stops the power transmission output control and supplies power from the power grid to the power load.

[0018] According to the above-described configuration, when the demand for power in the area where the first bypass piping is laid decreases significantly, and the supply of renewable energy to the power grid far exceeds the demand, the power load supplied by the power output control for transport power will prioritize the consumption of power from the power grid, thereby effectively suppressing the strain on the power grid.

[0019] Further characteristic features of the power transfer equipment are: The power load supplied with electricity from the aforementioned generator generates heat through the use of the supplied electricity, The feature is that it includes a heat medium circulation path that guides the cold energy recovered by the cold energy recovery heat exchanger to the power load and also guides the heat from the power load to the cold energy recovery heat exchanger.

[0020] This allows the cold energy contained in the gas after expansion in the expansion turbine to be recovered in a cold energy recovery heat exchanger located downstream of the expansion turbine. As a result, it is possible to supply cooling to power loads such as data centers that utilize the electricity transferred by the power transfer equipment and require cooling in conjunction with electricity usage. In other words, in locations where gas pipelines exist but the installation of power lines is difficult for economic reasons, etc., it is assumed that the supply of cooling and heating will also be difficult. However, in such locations, both electricity and cooling can be supplied effectively without the need to install power lines or new heat transfer fluid pipelines. [Brief explanation of the drawing]

[0021] [Figure 1] This diagram shows the gas flow state when the power transfer equipment according to the embodiment is in a normal gas supply state. [Figure 2] This figure shows the gas flow state when the power transfer equipment according to the embodiment is performing power transfer input control. [Figure 3] This figure shows the gas flow state when the power transfer equipment according to the embodiment is performing power transfer output control. [Figure 4] This diagram shows the gas flow state when the main gas piping is determined to be in an abnormal state in the power transfer equipment according to the embodiment. [Modes for carrying out the invention]

[0022] The power transfer equipment 100 and power transfer method according to an embodiment of the present invention relate to compressed air energy storage technology (CAES) that, while appropriately performing the conventional role of conventional equipment, can appropriately supply power from the pressure storage location to the power demand destination even when transmission equipment from the pressure storage location to the power demand destination cannot be secured using the conventional equipment, and can also appropriately supply the stored pressure energy in accordance with the energy demand. Hereinafter, embodiments of the power transfer equipment 100 and power transfer method according to the embodiment will be described based on Figures 1 to 4.

[0023] [Embodiment] As shown in Figure 1, the power transfer equipment 100 according to this embodiment includes a main gas pipe H1 through which gas (for example, city gas 13A) supplied from an upstream side such as a gas supply facility (not shown) can flow, and a first bypass pipe H2 through which gas can flow in a manner that bypasses the main gas pipe H1 in the event of an abnormality in the main gas pipe H1. Furthermore, the power transfer equipment 100 includes a first switching valve K1 that can switch the distribution state between a main distribution state (distribution state shown in Figure 1) in which the gas supplied from the upstream side is distributed to the main gas pipe H1 and a bypass distribution state (distribution state shown in Figures 2, 3, and 4) in which the gas is distributed to the first bypass pipe H2, and a closing valve at the inlet of the downstream connection part G2 between the first bypass pipe H2 and the main gas pipe H1 that closes the first bypass pipe H2 to a closed position including a fully closed state. The system includes an on-off valve V1 that can switch between an open state and an open state which includes an open state and a fully open state; an expansion turbine ET that causes pressurized gas to flow through and expand in the first bypass pipe H2; a generator E that generates electricity using the shaft output of the expansion turbine ET; a compressor C located downstream of the first switching valve K1 in the first bypass pipe H2 and upstream of the expansion turbine ET that pressurizes the gas led to the first bypass pipe H2; and a control device S that controls the distribution state of the first switching valve K1, the opening state of the on-off valve V1, and the drive state of the compressor C.

[0024] The control device S is constructed from hardware including a CPU (Central Processing Unit), RAM (Random Access Memory), and ROM (Read Only Memory), as well as software implemented therein. The control device S may be installed near the first bypass pipe H2 where the gas is stored and directly connected to various devices by wire or wireless connection, or it may be installed at a location away from the first bypass pipe H2 and configured to be electrically able to communicate with the aforementioned devices via a network line N such as the Internet.

[0025] In this embodiment, the main gas piping H1 is provided with a pressure regulating device RV downstream of the downstream connection G2 described above, which regulates the secondary pressure of the main gas piping H1 to a set pressure. The pressure regulating device RV can suitably utilize a commonly known pilot governor type pressure regulating device.

[0026] Furthermore, a second pressure gauge P2 for measuring gas pressure is provided at the inlet of the upstream connection section G1, which is the upstream connection point between the main gas pipe H1 and the first bypass pipe H2, where the first switching valve K1 is installed. In addition, a first pressure gauge P1 for measuring gas pressure is provided downstream of the downstream connection section G2 and upstream of the pressure regulating device RV. The control device S is configured to receive the pressure measured by the first pressure gauge P1 and the second pressure gauge P2 via wired or wireless connection. Incidentally, the gas piping such as the main gas piping H1 and the first bypass piping H2 described herein is made of steel, and for example, those designed to have a design allowable pressure of about 7.0 MPa are preferably used. Incidentally, gas at a primary pressure (for example, a pressure of about 2 MPa to 4 MPa) below the above design allowable pressure (for example, a pressure of about 7 MPa or less) usually flows through the main gas piping H1 and the first bypass piping H2.

[0027] The compressor C is located downstream of the first switching valve K1 in the first bypass piping H2 and upstream of the expansion turbine ET, and is configured to be rotationally driven by a motor M powered by a commercial power grid (not shown). The control device S controls the drive of the motor M, and can raise the pressure of the gas after compression by the compressor C to, for example, the design allowable pressure of the first bypass piping H2. From the viewpoint of improving the amount of accumulated pressure, which will be described later, it is preferable to install the compressor C at the outlet of the first switching valve K1 in the first bypass piping H2. In this specification, the outlet of a device means the vicinity of the connection point between the device and the piping downstream of it, and the inlet of a device means the vicinity of the connection point between the device and the piping upstream of it.

[0028] The expansion turbine ET is installed between the on-off valve V1 and the downstream connection G2 of the first bypass piping H2. When the gas is expanded in the expansion turbine ET, cold heat is generated, but in the expansion turbine ET according to this embodiment, a shaft levitation type is employed in which the rotating shaft is levitated from the bearing by magnetic force, so that it can be used for gas expansion even when the temperature drops to, for example, several tens of degrees Celsius. Incidentally, a cold energy recovery heat exchanger EX1 is provided at the outlet of the expansion turbine ET, which is capable of recovering the cold energy contained in the gas expanded by the expansion turbine ET.

[0029] The generator E, which is rotationally driven by the shaft output of the expansion turbine ET, is configured to include an inverter that can adjust the generated power to a desired frequency and voltage. The power generated by the generator E can be supplied via the first power line D1 to a computer CS, such as a supercomputer capable of performing predetermined calculations (an example of a power load that generates heat by using the supplied power). Here, the computer CS is also supplied with power from the commercial power grid via the second power line D2. Furthermore, the electricity generated by generator E can be suitably used not only for supplying to computer CS, but also for charging commercial electric vehicles, etc.

[0030] Now, the computer system CS, which consists of the supercomputers mentioned above, generates heat as it performs many calculations. Therefore, in this embodiment, the cooling energy of the gas recovered by the cooling energy recovery heat exchanger EX1 is guided to a cooler EX2 provided on the computer CS, which is a power load, and the heating energy of the computer CS is guided to the cooling energy recovery heat exchanger EX1, and a heat medium circulation path H5 is provided, and the heat medium is circulated in the heat medium circulation path H5 by a pump (not shown). As a result, the cooling energy generated by the expansion of the gas by the expansion turbine ET can be processed appropriately without incurring additional costs.

[0031] In the power transfer equipment 100 according to this embodiment, compressed air energy storage technology (CAES) utilizes the conventional first bypass piping H2 to appropriately supply power from the pressure storage location to the power demand destination even when power transmission equipment cannot be secured from the pressure storage location to the power demand destination. Furthermore, the following control is performed to appropriately supply the stored pressure energy in accordance with the energy demand.

[0032] Specifically, the control device S performs two types of transfer power input control: setting the first switching valve K1 to the bypass distribution state (the state shown in Figure 2), setting the on-off valve V1 to the closed open state (the state shown in Figure 2), driving the compressor C to accumulate pressure in the first bypass pipe H2 and put the expansion turbine ET into a non-rotating state; and setting the on-off valve V1 to the open open state (the state shown in Figure 3), releasing the gas pressure accumulated in the first bypass pipe H2 and putting the expansion turbine ET into a rotating state. In this context, it is preferable that the transfer power input control and transfer power output control be performed, for example, during nighttime hours when the amount of gas used on the upstream (secondary) side of the pressure regulating device RV is relatively low.

[0033] Furthermore, while the closed-open state basically means a fully closed state, from the perspective of maintaining rotation at the lowest rotational speed without stopping the rotation of the expansion turbine ET even in the closed-open state, it also includes maintaining a predetermined closed-side opening (for example, an opening of a few percent). The open position basically means the fully open position, but from the perspective of the processing capacity of the expansion turbine ET, it also includes maintaining an open position that is closer to the closed position than the fully open position.

[0034] As described above, when the control device S performs transfer power input control, for example, the gas flow state shown in Figure 2 is reached, and gas pressurized by the compressor C is pumped between the compressor C and the on-off valve V1 in the first bypass piping H2, thereby accumulating gas. This corresponds to the input of transfer power. On the other hand, when the control device S performs transfer power output control, for example, the gas flow state shown in Figure 3 is reached, and the gas pressurized in the first bypass piping H2 is released by expanding through the expansion turbine ET, generating electricity in the generator E. This corresponds to the output of transfer power. In other words, the piping between the compressor C and the expansion turbine ET in the first bypass piping H2 functions as the power transfer gas piping H2a (the piping within the range of L1 in the drawing) that transfers electricity.

[0035] Incidentally, in the gas flow state shown in Figure 3, gas is introduced to compressor C and compressor C is driven, and gas is stored in the power transfer gas piping H2a up to the on-off valve V1. In other words, the input and output of transfer power occur simultaneously. Here, in mobile power output control, it is not necessary for compressor C to be driven.

[0036] Furthermore, in the power transfer output control, if an abnormality is detected in the main gas piping H1, the pressure in the power transfer gas piping H2a up to the shut-off valve V1 is controlled to reach the lower limit pressure value for power transfer output (for example, a pressure of approximately 3.0 MPa or higher) in order to quickly supply gas to the downstream side (secondary side) using the first bypass piping H2. With the above control, electricity can be suitably transported via the power transfer gas piping H2a over the distance indicated by L1 in the drawing, in areas where a power grid is not provided.

[0037] Furthermore, the power transfer equipment 100 according to this embodiment is equipped with a pressure regulating device RV to maintain the secondary pressure at a set pressure. However, the pressure regulating device RV cannot control the secondary pressure to the desired pressure (set pressure) unless the secondary pressure is equal to or greater than the set pressure. Therefore, the control device S performs transfer power input control and transfer power output control to maintain the primary side pressure of the pressure regulating device RV at or above the set pressure. To elaborate, when the control device S is performing transfer power input control, in other words, when the first switching valve K1 is in the bypass distribution state and the on-off valve V1 is in the closed open state, and gas is not supplied to the upstream side (primary side) of the pressure regulating device RV, and the pressure measured by the first pressure gauge P1 is less than the set pressure, the control device S performs either a first switching control to switch the first switching valve K1 from the bypass distribution state to the main distribution state, or a second switching control to switch the on-off valve V1 from the closed open state to the open open state. In this case, the control device S may perform both the first and second switching controls.

[0038] Furthermore, in the power transfer equipment 100 according to this embodiment, as described above, the computer CS (an example of a power load) to which power is supplied from the generator E is configured to also be able to receive power from the power grid (not shown) in the area where the first bypass pipe H2 is laid. In order to prevent the power grid from becoming congested due to the supply from the power grid exceeding the demand, the power transfer equipment 100 performs the following control. In other words, the control device S is configured to receive whether the power demand in the power grid in the area where the first bypass pipe H2 is laid is below a predetermined lower limit threshold for power demand. When the control device S receives that the power demand in the power grid is below the lower limit threshold for power demand, it stops the power output control for transport and supplies power from the power grid to the computer CS. Thus, the power transfer equipment 100 according to this embodiment functions well as power transfer equipment that can flexibly respond to power grid congestion.

[0039] Now, the first bypass pipe H2 is provided to ensure a smooth supply of gas to the downstream (secondary) side even if damage or other abnormalities occur in the main gas pipe H1. In order to perform this function, the power transfer equipment 100 according to this embodiment may be configured as follows. That is, as shown in Figure 4, the first bypass pipe H2 may be equipped with a second bypass pipe H3 that bypasses the compressor C, and a second switching valve K2 that can switch between a first flow state (not shown) in which gas is guided to the compressor C but not through the second bypass pipe H3, and a second flow state (shown in Figure 4) in which gas is guided through the second bypass pipe H3 but not through the compressor C. The control device S is configured to perform a determination process that can determine whether the main gas piping H1 downstream of the upstream connection G1 is in an abnormal state. If the determination process determines that the main gas piping H1 is in an abnormal state, the control device S will perform the following controls in both the transfer power input control and the transfer power output control: switch the first switching valve K1 to the bypass distribution state, switch the second switching valve K2 to the second flow state, and switch the on / off valve V1 to the open state. This ensures that even if an abnormality occurs in the main gas pipeline H1, gas can be supplied to secondary consumers smoothly by passing it through the first bypass pipeline H2.

[0040] Furthermore, in the above determination process, the control device S determines that the main gas piping H1 is in an abnormal state if, for example, the pressure of the first pressure gauge P1 decreases over time while the pressure regulating device RV is seismically shut off.

[0041] [Another embodiment] (1) In the above embodiment, the first switching valve K1 is exemplified as being composed of one three-way switching valve. The first switching valve K1 may be composed of, for example, an on-off valve for opening and closing the main gas pipe H1 and an on-off valve for opening and closing the first bypass pipe H2. The same applies to the second switching valve K2; it may be composed of two switching valves instead of a single three-way switching valve.

[0042] (2) The equipment for energy storage consisting of a compressor C and a drive motor M, and the equipment for discharge consisting of an expansion turbine ET and a generator E, may each be configured to consist of multiple units.

[0043] (3) In the above embodiment, the first pressure gauge P1 and the second pressure gauge P2 do not necessarily have to be provided. In this case, the control device S does not perform control based on the pressure measured by the first pressure gauge P1 and the second pressure gauge P2.

[0044] (4) In the above embodiment, the power transfer equipment 100 does not necessarily have to be provided with a pressure regulating device RV.

[0045] (5) In the above embodiment, a configuration may be adopted in which a heating device for heating gas is provided at the inlet of the expansion turbine ET. In this configuration, if the temperature of the gas input to the expansion turbine ET can be raised to a sufficiently high temperature, it is not necessary to use a shaft-levitation type expansion turbine ET.

[0046] (6) In the above embodiment, the computer CS as a power load does not necessarily have to be provided.

[0047] Furthermore, the configurations disclosed in the above embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with configurations disclosed in other embodiments, provided that no inconsistencies arise. Moreover, the embodiments disclosed herein are illustrative, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate without departing from the object of the present invention. [Industrial applicability]

[0048] The power transfer equipment and power transfer method of the present invention, in compressed air energy storage technology (CAES), appropriately fulfill the conventional role of conventional equipment, while also enabling the appropriate supply of power from the pressure storage location to the power demand destination even when transmission equipment from the pressure storage location to the power demand destination cannot be secured using the conventional equipment. Furthermore, it can be effectively used as power transfer equipment and a power transfer method that can appropriately supply the stored pressure energy in accordance with energy demand. [Explanation of Symbols]

[0049] 100: Power transfer equipment C: Compressor CS: Calculator E: Generator ET: Expansion Turbine EX1:Cold heat recovery heat exchanger G1: Upstream connection G2: Downstream connection H1: Main gas piping H2: First bypass piping H2a: Power transfer gas piping H3: Second bypass piping H5: Heat medium circulation path K1: First switching valve K2: Second switching valve L1: Drawing RV:Pressure regulator S: Control device V1: Shut-off valve

Claims

1. A power transfer facility comprising a main gas pipe through which gas supplied from the upstream side can flow, and a first bypass pipe through which gas can flow in a manner that bypasses the main gas pipe in the event of an abnormality in the main gas pipe, A first switching valve capable of switching the distribution state of gas supplied from the upstream side between a main distribution state, in which the gas is distributed to the main gas pipe, and a bypass distribution state, in which the gas is distributed to the first bypass pipe. At the inlet of the downstream connection between the first bypass piping and the main gas piping, an on / off valve is provided that can switch the opening state of the first bypass piping between a closed opening state, which includes a fully closed state, and an open opening state, which includes a fully open state. An expansion turbine is provided between the outlet of the on / off valve of the first bypass piping and the downstream connection portion, and causes the gas stored in the first bypass piping to flow through and expand. A generator that generates electricity using the shaft output of the expansion turbine, A compressor located downstream of the first switching valve in the first bypass piping, which pressurizes the gas being supplied to the first bypass piping, The system includes a control device that controls the distribution state of the first switching valve, the opening state of the on / off valve, and the drive of the compressor, The control device performs the following: transfer power input control, which sets the first switching valve to the bypass distribution state, sets the on-off valve to the closed open state, drives the compressor to accumulate pressure in the first bypass piping and puts the expansion turbine into a non-rotating state; and transfer power output control, which sets the on-off valve to the open open state and releases the gas pressure accumulated in the first bypass piping to put the expansion turbine into a rotating state. A power transfer facility in which the piping between the compressor and the expansion turbine of the first bypass piping acts as a power transfer gas piping for transferring electricity.

2. The aforementioned expansion turbine is a shaft-levitation type expansion turbine in which the rotating shaft is levitated from the bearing by magnetic force, The power transfer equipment according to claim 1, wherein the outlet of the expansion turbine in the first bypass piping is provided with a cold energy recovery heat exchanger capable of recovering the cold energy of the gas expanded by the expansion turbine.

3. The first bypass piping is provided with a second bypass piping that bypasses the compressor, and a second switching valve is provided that can switch between a first flow state in which gas flows through the first bypass piping but not through the second bypass piping, and a second flow state in which gas does not flow through the first bypass piping but flows through the second bypass piping. The control device is configured to perform a determination process capable of determining whether the main gas piping downstream of the upstream connection point between the main gas piping and the first bypass piping is in an abnormal state. The power transfer equipment according to claim 1 or 2, wherein, if the control device determines in the determination process that the main gas piping is in the abnormal state, it switches the first switching valve to the bypass distribution state, switches the second switching valve to the second flow state, and switches the on / off valve to the open state, regardless of whether the power transfer input control or the power transfer output control is being performed.

4. The main gas piping is provided with a pressure regulating device downstream of the downstream connection portion for regulating the secondary pressure of the main gas piping to a set pressure. The power transfer equipment according to claim 1 or 2, wherein the control device performs the power transfer input control and the power transfer output control so as to maintain the primary side pressure of the pressure regulating device at or above the set pressure.

5. The power load supplied with power from the generator is configured to also be able to receive power from the power grid in the area where the first bypass piping is laid. The control device is configured to receive whether the power demand in the power grid in the area where the first bypass piping is laid is below a predetermined lower limit threshold for power demand, The power transfer equipment according to claim 1 or 2, wherein the control device, upon receiving that the power demand in the power grid is below the power demand lower limit threshold, stops at least the power transfer output control and supplies power from the power grid to the power load.

6. The power load supplied with electricity from the aforementioned generator generates heat through the use of the supplied electricity, The power transfer equipment according to claim 2, further comprising a heat medium circulation path that guides the cold energy recovered in the cold energy recovery heat exchanger to the power load and the heat energy of the power load to the cold energy recovery heat exchanger.

7. The system includes a main gas pipe through which gas supplied from the upstream side can pass, and a first bypass pipe through which gas can pass in a manner that bypasses the main gas pipe in the event of an abnormality in the main gas pipe. A first switching valve capable of switching the distribution state of gas supplied from the upstream side between a main distribution state, in which the gas is distributed to the main gas pipe, and a bypass distribution state, in which the gas is distributed to the first bypass pipe. At the inlet of the downstream connection between the first bypass piping and the main gas piping, an on / off valve is provided that can switch the opening state of the first bypass piping between a closed opening state, which includes a fully closed state, and an open opening state, which includes a fully open state. An expansion turbine is provided between the outlet of the on / off valve of the first bypass piping and the downstream connection portion, and causes the gas stored in the first bypass piping to flow through and expand. A generator that generates electricity using the shaft output of the expansion turbine, A power transfer method in a power transfer facility comprising a compressor that increases the pressure of the gas led to the first bypass piping downstream of the first switching valve of the first bypass piping, A power transfer method comprising: a power input control that sets the first switching valve to the bypass distribution state, the on-off valve to the closed open state, drives the compressor to accumulate gas pressure in the first bypass piping, and sets the expansion turbine to a non-rotating state; and a power output control that sets the on-off valve to the open open state, releases the gas pressure accumulated in the first bypass piping, and sets the expansion turbine to a rotating state.

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