JP5415483B2 - Steam system - Google Patents

Description

  The present invention relates to a steam system that uses steam to drive a compressor, a blower, and the like.

  A steam system (1) disclosed in Patent Document 1 below is known. This steam system includes a prime mover (steam engine 2) that generates power using steam, and a driven machine (air compressor 3) driven by the prime mover, and includes a fluid load (use load of compressed air) and a steam load. The steam supply to the prime mover is controlled based on the (steam usage load). In addition, steam can be supplied to the location where steam after use in the prime mover is supplied via the bypass passage (13) without going through the prime mover, and a bypass valve (14) is provided in the bypass passage. It has been.

This steam system is controlled as follows.
(A) When there is a fluid load and a steam load, supply steam to the prime mover.
(B) When there is no fluid load or steam load, the steam supply to the prime mover is stopped.
(C) When there is no fluid load but there is a steam load, the steam is supplied to the prime mover via the bypass passage while the supply of steam to the prime mover is stopped.
(D) When there is a fluid load but no steam load, the driven machine or the second driven machine having the same function is driven by an electric motor.

Japanese Patent No. 4240155 (Claims 1-3, 5-7)

  The invention disclosed in Patent Document 1 operates based on a fluid load and a steam load. However, the applicant has been eagerly researching more specific control. For example, when there is both a fluid load and a steam load, the steam supply to the prime mover is executed, but how the control is specifically executed, that is, the control based on the fluid load or the steam load We have been diligently researching whether to control, which to execute, and how to switch between the two controls.

  In addition, when a waste heat boiler or an exhaust gas boiler is used as a boiler installed on the steam supply side to the prime mover, the amount of generated steam becomes unsatisfactory, so the steam pressure on the inlet side of the prime mover moves up and down. Therefore, in addition to the control based on the fluid load and the control based on the steam load described above, there are cases where it is desired to control the steam supply to the prime mover based on the steam pressure on the inlet side of the prime mover. In that case, how to switch the three types of control becomes a further problem.

  The present invention has been made in view of such circumstances, and in a steam system for driving a compressor or the like using a steam engine, control based on a fluid load, control based on a steam load, and, if desired, an inlet of a prime mover It is an object to efficiently operate the steam system by appropriately switching these controls including the control based on the steam pressure on the side.

  The present invention has been made to solve the above-mentioned problems. The invention according to claim 1 is a motor that generates power using steam, and a driven machine that is driven by the motor and sucks and discharges fluid. A first pressure sensor that detects the pressure of the fluid on the discharge side of the driven machine, and a second pressure sensor that detects the pressure of the steam on the exhaust side of the prime mover, and the detected pressure of the first pressure sensor When the pressure rises, the amount of steam supplied to the prime mover is decreased, and the amount of steam supplied to the prime mover is controlled based on the detected pressure of the first pressure sensor with a reverse operation type characteristic, or the detected pressure of the second pressure sensor is Control of the amount of steam supplied to the prime mover based on the pressure detected by the second pressure sensor and the control based on the pressure detected by the first pressure sensor. And the second pressure Among the control based on the detected pressure of the sensor, a steam system, characterized in that to switch to control the supply 蒸量 decreases to the prime mover.

  For example, if the amount of steam used on the exhaust side of the prime mover decreases while the amount of steam supplied to the prime mover is being controlled based on the pressure detected by the first pressure sensor (fluid pressure on the discharge side of the driven machine), As the steam pressure increases, it is necessary to stop the prime mover. On the other hand, if the amount of fluid used on the discharge side of the driven machine decreases while the amount of steam supplied to the prime mover is being controlled based on the pressure detected by the second pressure sensor (steam pressure on the exhaust side of the prime mover), the discharge side of the driven machine As the fluid pressure increases, it is necessary to stop the prime mover. However, according to the invention described in claim 1, of the control based on the detection pressure of the first pressure sensor and the control based on the detection pressure of the second pressure sensor, the control for reducing the steam supply amount to the prime mover. By appropriately switching, the operation of the prime mover can be continued according to the amount of fluid and steam used.

  The invention according to claim 2 further includes a third pressure sensor for detecting a steam pressure on a steam supply side of the prime mover, and when the detected pressure of the first pressure sensor increases, the steam supply amount to the prime mover is reduced. The amount of steam supplied to the prime mover is decreased when the detected pressure of the second pressure sensor is increased or the amount of steam supplied to the prime mover is controlled based on the detected pressure of the first pressure sensor. A reverse operation type characteristic that controls the amount of steam supplied to the prime mover based on the detected pressure of the second pressure sensor, or increases the amount of steam supplied to the prime mover when the detected pressure of the third pressure sensor increases. Control the amount of steam supplied to the prime mover based on the detected pressure of the third pressure sensor with the characteristics of the operation type, control based on the detected pressure of the first pressure sensor, and control based on the detected pressure of the second pressure sensor And the third pressure Among the control based on the detected pressure of the sensor, a steam system according to claim 1, characterized in that switching to the least becomes controlled feeding 蒸量 is to the prime mover.

  According to the second aspect of the present invention, the control based on the detected pressure of the first pressure sensor (the fluid pressure on the discharge side of the driven machine) and the detected pressure of the second pressure sensor (the steam pressure on the exhaust side of the prime mover) In addition to control based on the detection pressure of the third pressure sensor (steam pressure on the steam supply side of the prime mover), the use of fluids and steam is appropriately switched to control that minimizes the amount of steam supply to the prime mover. The operation of the prime mover can be continued according to the amount and the amount of steam generated.

  The invention according to claim 3 is provided with a steam supply valve that adjusts an amount of steam supplied to the prime mover by adjusting an opening degree in a steam feed path to the prime mover, and adjusts an output of the prime mover. When the detected pressure of the first pressure sensor rises, the steam supply valve is controlled based on the detected pressure of the first pressure sensor with a reverse operation type characteristic that decreases the opening of the steam supply valve, or the second pressure When the detection pressure of the sensor rises, the steam supply valve is controlled based on the detection pressure of the second pressure sensor with a reverse operation type characteristic that reduces the opening of the steam supply valve, or the detection pressure of the third pressure sensor Control the steam supply valve based on the detected pressure of the third pressure sensor with a positive-acting characteristic that increases the opening of the steam supply valve when the pressure rises, and control based on the detected pressure of the first pressure sensor; Control based on the pressure detected by the second pressure sensor, and the third Among the control based on the detected pressure of the force sensor, a steam system according to claim 2, wherein the switch to control the opening degree of the supply 蒸弁 is minimized.

  According to the invention of claim 3, switching between control based on the detection pressure of the first pressure sensor, control based on the detection pressure of the second pressure sensor, and control based on the detection pressure of the third pressure sensor, This can be done simply by adjusting the opening of the steam supply valve provided in the steam supply path to the prime mover.

  According to a fourth aspect of the present invention, the amount of steam used on the exhaust side of the prime mover and the amount of steam generated on the steam supply side of the prime mover are required by control based on the fluid pressure on the discharge side of the prime mover. When the amount of steam passing through the prime mover is greater, the steam supply valve is controlled based on the fluid pressure on the discharge side of the driven machine, and the amount of steam used on the exhaust side of the prime mover is the fluid on the discharge side of the driven machine The amount of generated steam on the steam supply side of the prime mover is less than the amount of steam passing through the prime mover required in the control based on the pressure, but the passage of the prime mover required in the control based on the fluid pressure on the discharge side of the driven device When the amount of steam is larger, the steam supply valve is controlled based on the steam pressure on the exhaust side of the prime mover, and the amount of steam used on the exhaust side of the prime mover is based on the fluid pressure on the discharge side of the driven machine More than the amount of steam passing through the prime mover required for control. When the amount of steam generated on the steam supply side of the prime mover is smaller than the amount of passing steam of the prime mover required by the control based on the fluid pressure on the discharge side of the driven device, the steam pressure on the steam supply side of the prime mover The prime mover that controls the steam supply valve, and that the amount of steam used on the exhaust side of the prime mover and the amount of steam generated on the steam supply side of the prime mover are required by control based on the fluid pressure on the discharge side of the prime mover When the generated steam amount is less than the used steam amount, the steam supply valve is controlled based on the steam pressure on the steam supply side of the prime mover, and the steam used on the exhaust side of the prime mover is controlled. And the amount of steam generated on the steam supply side of the prime mover is less than the amount of steam passing through the motor required by the control based on the fluid pressure on the discharge side of the driven device, and the amount of steam used is less than the amount of steam generated Based on the steam pressure on the exhaust side of the prime mover A steam system according to claim 3, characterized in that to control the serial supply 蒸弁.

  According to the invention described in claim 4, the passing steam amount of the prime mover required in the control based on the fluid pressure on the discharge side of the driven machine, the used steam amount on the exhaust side of the prime mover, and the steam supply side of the prime mover Switching between control based on the detected pressure of the first pressure sensor, control based on the detected pressure of the second pressure sensor, and control based on the detected pressure of the third pressure sensor, depending on the relationship with the amount of generated steam. Will do. The fourth aspect explicitly shows the contents achieved based on the third aspect of the invention.

  According to a fifth aspect of the present invention, the driven machine is an air compressor, and the first pressure sensor is configured to measure a pressure in an air path from the air compressor to a compressed air utilization device or an air tank provided in the air path. And the second pressure sensor detects a pressure in a steam path from the prime mover to the steam using device or a steam header provided in the steam path, and the third pressure sensor detects a steam path from the boiler to the prime mover or in the steam path. The steam system according to any one of claims 2 to 4, wherein the pressure in the provided steam header is detected.

  According to the fifth aspect of the present invention, compressed air can be produced using steam as a drive source. Moreover, each sensor may be provided not only in a pipe line but in an air tank or a steam header.

  According to a sixth aspect of the present invention, the air passage or the air tank is driven by compressed air from a first air compressor driven by the prime mover and a driving source different from the first air compressor. Compressed air from the second air compressor can be supplied, and the first air compressor first sets the detected pressure of the first pressure sensor in the control based on the detected pressure of the first pressure sensor. The second air compressor is controlled to maintain the detected pressure of the first pressure sensor at a second set value, and the second set value is greater than the first set value. The steam system according to claim 5, wherein the steam system is set low.

  According to the sixth aspect of the present invention, when the compressed air from the first air compressor is not enough, the compressed air from the second air compressor can be supplied. In addition, the operation of the prime mover can be prioritized by lowering the set pressure of the second air compressor below the control pressure of the first air compressor.

  According to the seventh aspect of the present invention, steam via the prime mover and steam via a bypass valve can be supplied to the steam path or steam header from the prime mover to the steam utilization device without passing through the prime mover. The prime mover is controlled to maintain the detected pressure of the second pressure sensor at a third set value in the control based on the detected pressure of the second pressure sensor, and the bypass valve is controlled by the second pressure sensor. The steam according to claim 5 or 6, wherein the opening degree is adjusted to maintain the detected pressure at a fourth set value, and the fourth set value is set lower than the third set value. System.

  According to invention of Claim 7, when only the steam from a motor | power_engine is not enough, the steam via a bypass valve can be supplied. In addition, the operation of the prime mover can be prioritized by setting the set pressure of the bypass valve lower than the control pressure of the prime mover.

  Furthermore, in the invention according to claim 8, the steam supply amount to the prime mover is such that the detected pressure of the third pressure sensor is maintained at the fifth set value in the control based on the detected pressure of the third pressure sensor. And the boiler is controlled to maintain the detected pressure of the third pressure sensor at a sixth set value, or the evaporating valve provided on the upstream side of the prime mover detects the detected pressure of the third pressure sensor. The opening degree is adjusted so as to be maintained at the sixth set value, and the sixth set value is set to be higher than the fifth set value. It is a steam system.

  According to the eighth aspect of the present invention, the steam pressure on the steam supply side of the prime mover is adjusted by the boiler or the steam release valve. In addition, the operation of the prime mover can be prioritized by setting the control pressure of the boiler or the set pressure of the evaporative valve higher than the control pressure of the prime mover.

  According to the present invention, in a steam system that drives a compressor or the like using a steam engine, including control based on fluid load, control based on steam load, and control based on steam pressure on the inlet side of the prime mover as desired, By appropriately switching these controls, the steam system can be operated efficiently.

It is the schematic which shows one Example of the steam system of this invention. It is a figure which shows the switching condition of the control of the steam supply valve in the steam system of FIG.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view showing an embodiment of the steam system of the present invention. The steam system 1 according to the present embodiment includes a prime mover (steam engine 2) that generates power using steam and a driven machine (compressor 3) driven by the prime mover. In addition, you may comprise a motor and a driven machine as the unit 4 so that it may be enclosed with a dashed-dotted line in FIG.

  The prime mover is a steam engine (steam motor) 2 that generates power by receiving steam. The prime mover is not particularly limited in its configuration, but is, for example, a screw-type steam engine.

  The driven machine is a device that is driven by the steam engine 2 and sucks and discharges fluid. More specifically, the driven machine is the compressor 3 or the blower. Hereinafter, although a driven machine is demonstrated as an air compressor, the structure and control of the steam system 1 are the same also in the case of other compressors or blowers.

  The compressor 3 sucks outside air, compresses it, and discharges it. The compressed air from the compressor 3 is sent to various types of compressed air utilization equipment (not shown) via the air path 5. An air tank (not shown) as a buffer tank may be provided in the middle of the air path 5 as desired.

  A compressor (second air compressor) driven by a driving source different from the compressor 3 is provided in an air passage 5 from the compressor (first air compressor) 3 to the compressed air utilization device or an air tank provided in the air passage 5. ) Is preferably supplied. For example, a compressor 3 driven by a steam engine 2 and a compressor driven by an electric motor are provided, and compressed air from each compressor can be supplied to one or a plurality of compressed air utilization devices via an air tank. It is said. At this time, two compressors may be shared, and one compressor may be driven by the steam engine 2 and the electric motor.

  Steam from the boiler 6 is supplied to the steam engine 2 via a steam supply path 7. At this time, the steam from the boiler 6 may be temporarily supplied to a steam header (not shown), and the steam from the steam header may be supplied to the steam engine 2.

  Steam from another steam generation source may be supplied to the steam supply path 7 from the boiler 6 to the steam engine 2 or the steam header provided thereto. In particular, when the boiler 6 is a waste heat boiler or an exhaust gas boiler, the amount of generated steam is probable. Therefore, only the steam from the boiler 6 is not sufficient, and if the steam pressure falls below a predetermined level, steam from other steam generating sources. May be supplied. In this case, a fuel-fired boiler or an electric boiler is preferably used as another steam generation source.

  A steam supply valve 8 is provided in the steam supply path 7 to the steam engine 2. By adjusting the opening degree of the steam supply valve 8, the output of the steam engine 2, that is, the rotational speed can be controlled.

  The steam supplied to the steam engine 2 is used in the steam engine 2, expanded, decompressed, and discharged. The relatively low-pressure steam after being used in the steam engine 2 is sent to various steam utilizing devices (not shown) via the steam path 9. At this time, the steam from the steam engine 2 may be once supplied to the steam header 10, and the steam from the steam header 10 may be supplied to the steam utilization device.

  It is preferable that steam via a bypass valve (not shown) can be supplied to the steam path 9 from the steam engine 2 to the steam-utilizing device or the steam header 10 provided on the steam path. For example, steam from the boiler 6 or other steam generation source is supplied to the steam header 10 via the bypass valve without passing through the steam engine 2. Alternatively, the steam supply path 7 to the steam engine 2 and the steam path 9 from the steam engine 2 may be connected by a bypass path (not shown), and a bypass valve may be provided in the bypass path.

  A first pressure sensor 11 that detects the pressure of compressed air is provided on the discharge side of the compressor 3. More specifically, the first pressure sensor 11 is provided in the air passage 5 from the compressor 3 to the compressed air utilization device or the air tank provided in the air passage 5. Based on the detected pressure of the first pressure sensor 11, the use load of the compressed air in the compressed air utilization device can be grasped. For example, if the amount of compressed air used in the compressed air utilization device is larger than the amount of compressed air produced by the compressor 3, the pressure detected by the first pressure sensor 11 decreases, and therefore the use load of compressed air is large. I understand.

  When the pressure detected by the first pressure sensor 11 falls below a predetermined level and it is determined that the compressed air from the compressor (first air compressor) 3 alone cannot be covered, as described above, other compression is performed. It is preferable to supply compressed air from a compressor (second air compressor). In that case, the first air compressor 3 is controlled to maintain the detected pressure of the first pressure sensor 11 at the first set value, and the second air compressor sets the detected pressure of the first pressure sensor 11 to the second set value. It is controlled to maintain the value, and the second set value may be set lower than the first set value.

  A second pressure sensor 12 that detects the pressure of the steam is provided on the steam exhaust side of the steam engine 2. More specifically, the second pressure sensor 12 is provided in the steam path 9 from the steam engine 2 to the steam using device or the steam header 10 provided in the steam path 9. From the detected pressure of the second pressure sensor 12, it is possible to grasp the steam utilization load in the steam utilization device. For example, if the amount of steam used in the steam-utilizing device is larger than the amount of steam discharged from the steam engine 2, the detected pressure of the second pressure sensor 12 decreases, so it can be understood that the steam utilization load is large.

  When the pressure detected by the second pressure sensor 12 falls below a predetermined level and it is determined that the steam from the steam engine 2 alone cannot be covered, as described above, the steam is supplied via the bypass valve. preferable. In that case, the steam engine 2 is controlled to maintain the detected pressure of the second pressure sensor 12 at the third set value, and the bypass valve is opened to maintain the detected pressure of the second pressure sensor 12 at the fourth set value. The fourth set value may be set lower than the third set value. The bypass valve may be a self-reducing pressure reducing valve that operates substantially in the same manner as the motor-operated valve controlled based on the pressure detected by the second pressure sensor 12.

  A steam supply side of the steam engine 2 is provided with a third pressure sensor 13 that detects steam pressure. More specifically, the third pressure sensor 13 is provided in the steam supply path 7 from the boiler 6 to the steam engine 2 or in the steam header provided therein. From the detected pressure of the third pressure sensor 13, the amount of steam generated by the boiler 6 can be grasped. For example, when the boiler 6 is a waste heat boiler or an exhaust gas boiler, the amount of generated steam is appropriate. Since the detected pressure decreases, it can be seen that the amount of steam generated by the boiler 6 is small. On the other hand, when the boiler 6 is a fuel-fired boiler or an electric boiler, the output can be adjusted so as to maintain the detected pressure of the third pressure sensor 13 as desired.

  As will be described later, when the steam supply amount to the steam engine 2 is controlled based on the detected pressure of the third pressure sensor 13, the steam supply amount to the steam engine 2 is set to the fifth detection pressure of the third pressure sensor 13. Controlled to maintain the value. On the other hand, when the boiler 6 is a fuel-fired boiler or an electric boiler, the boiler 6 is controlled to maintain the detection pressure of the third pressure sensor 13 at the sixth set value. When the boiler 6 is a waste heat boiler or an exhaust gas boiler, the steam supply valve 8 An opening degree of an external steaming valve (not shown) provided on the upstream side is adjusted so as to maintain the detected pressure of the third pressure sensor 13 at the sixth set value. The sixth set value is set higher than the fifth set value. The evaporative valve may be a self-reducing pressure reducing valve that operates substantially in the same manner as the motor-operated valve controlled based on the pressure detected by the third pressure sensor 13.

  In the steam system 1 of the present embodiment, the steam supply valve 8 is controlled based on the detected pressures of the first pressure sensor 11, the second pressure sensor 12, and the third pressure sensor 13. More specifically, the first controller 14 that adjusts the opening of the steam supply valve 8 based on the detected pressure of the first pressure sensor 11 and the opening of the steam supply valve 8 based on the detected pressure of the second pressure sensor 12. And a third controller 16 that adjusts the opening of the steam supply valve 8 based on the pressure detected by the third pressure sensor 13. However, the outputs from these controllers 14 to 16 are once sent to the signal selector 17, and the signal selector 17 selects the output from any one of the controllers and based on that, the steam supply valve Adjust the opening of 8.

  The first controller 14 controls the amount of steam supplied to the steam engine 2 based on the detected pressure P <b> 1 of the first pressure sensor 11. More specifically, when the detected pressure P1 of the first pressure sensor 11 decreases, the first controller 14 increases the amount of steam that passes through the steam engine 2 by increasing the opening degree M1 of the steam supply valve 8 (that is, steam When the detected pressure P1 of the first pressure sensor 11 is increased while the rotation speed of the engine 2 is increased), the opening M1 of the steam supply valve 8 is decreased to reduce the amount of steam passing through the steam engine 2 (that is, the steam engine 2). The feed valve 8 is controlled based on the detected pressure P1 of the first pressure sensor 11 (PID) so that the detected pressure P1 of the first pressure sensor 11 is maintained as desired. Control.

  The second controller 15 controls the amount of steam supplied to the steam engine 2 based on the detected pressure P2 of the second pressure sensor 12. More specifically, when the detected pressure P2 of the second pressure sensor 12 decreases, the second controller 15 increases the opening amount M2 of the steam supply valve 8 to increase the amount of steam passed through the steam engine 2, When the detected pressure P2 of the second pressure sensor 12 increases, the opening pressure M2 of the steam supply valve 8 is reduced to reduce the amount of steam passing through the steam engine 2, and the detected pressure of the second pressure sensor 12 The steam supply valve 8 is controlled (PID control) based on the detected pressure P2 of the second pressure sensor 12 so as to maintain P2 as desired.

  The third controller 16 controls the amount of steam supplied to the steam engine 2 based on the detected pressure of the third pressure sensor 13. More specifically, when the detected pressure P3 of the third pressure sensor 13 decreases, the third controller 16 reduces the amount of steam passing through the steam engine 2 by decreasing the opening M3 of the steam supply valve 8, When the detected pressure P3 of the third pressure sensor 13 increases, the opening pressure M3 of the steam supply valve 8 is increased to increase the amount of steam passing through the steam engine 2, and the detected pressure of the third pressure sensor 13 is increased. The steam supply valve 8 is controlled (PID control) based on the detected pressure P3 of the third pressure sensor 13 so as to maintain P3 as desired.

  The signal selector 17 selects the one with the smallest opening degree among the opening setting signals M1 to M3 of the steam supply valve 8 by the first controller 14, the second controller 15 and the third controller 16 described above. Then, the steam supply valve 8 is controlled. That is, control based on the detected pressure P1 of the first pressure sensor 11 by the first controller 14, control based on the detected pressure P2 of the second pressure sensor 12 by the second controller 15, and third control by the third controller 16. Of the control based on the detected pressure P3 of the pressure sensor 13, the control is switched to the control in which the opening degree of the steam supply valve 8 is minimized (that is, the control in which the steam supply amount to the steam engine 2 is minimized).

  FIG. 2 is a diagram illustrating a switching state of control of the steam supply valve 8 in the steam system 1 of the present embodiment. As shown in this figure, the steam system 1 of the present embodiment operates as follows.

(1) Control based on the compressed air pressure on the discharge side of the compressor 3 (that is, the first controller 14), based on the amount of steam used on the exhaust side of the steam engine 2 and the amount of steam generated on the steam supply side of the steam engine 2. The control is based on the detected pressure of the first pressure sensor 11), and the amount of steam passing through the steam engine is larger.
In this case, the steam supply valve 8 is controlled based on the compressed air pressure on the discharge side of the compressor 3. More specifically, the pressure on the steam supply side of the steam engine 2 is adjusted by the amount of steam generated by the boiler 6 or the amount of steam discharged by the steam release valve, and the output of the third controller 16 (target opening of the steam supply valve 8 is opened). Degree) M3 is maintained substantially at the upper limit. Moreover, on the steaming side of the steam engine 2, steam to the steam utilization equipment is covered by steam from other steam systems (steam through a bypass valve), and the output of the second controller 15 (of the steam supply valve). The target opening degree M2 is maintained at an upper limit value. Therefore, among the outputs from the three controllers 14 to 16, the output (target opening of the steam supply valve) M1 of the first controller 14 becomes the minimum value, and the signal selector 17 outputs the first controller 14 M1 is selected, and the opening degree of the steam supply valve 8 is adjusted based on the signal.

(2) Although the amount of steam used on the exhaust side of the steam engine 2 is less than the amount of steam passing through the steam engine required by the control based on the compressed air pressure on the discharge side of the compressor 3, When the amount of generated steam is larger than the amount of steam passing through the steam engine required for control based on the compressed air pressure on the discharge side of the compressor 3.
In this case, the steam supply valve 8 is controlled based on the steam pressure on the exhaust steam side of the steam engine 2. More specifically, when the amount of steam passing through the steam engine exceeds the amount of steam used on the exhaust side of the steam engine 2, the detected pressure P2 of the second pressure sensor 12 increases. Therefore, the second controller 15 decreases the output M2 in order to decrease the detected pressure P2 of the second pressure sensor 12, and becomes lower than the output M1 of the first controller 14, and the signal selector 17 performs the second control. The output M2 of the vessel 15 is selected, and the opening degree of the steam supply valve 8 is adjusted based on the signal.

(3) Although the amount of steam used on the exhaust side of the steam engine 2 is larger than the amount of steam passing through the steam engine required by the control based on the compressed air pressure on the discharge side of the compressor 3, When the amount of generated steam is less than the amount of steam passing through the steam engine required by the control based on the compressed air pressure on the discharge side of the compressor 3.
In this case, the steam supply valve 8 is controlled based on the steam pressure on the steam supply side of the steam engine 2. More specifically, when the amount of steam passing through the steam engine exceeds the amount of steam generated on the steam supply side of the steam engine 2, the detected pressure of the third pressure sensor 13 decreases. Therefore, the third controller 16 decreases the output M3 in order to increase the detected pressure P3 of the third pressure sensor 13, and becomes lower than the output M1 of the first controller 14, and the signal selector 17 performs the third control. The output M3 of the vessel 16 is selected, and the opening degree of the steam supply valve 8 is adjusted based on the signal.

(4) The amount of steam used on the exhaust steam side of the steam engine 2 and the amount of steam generated on the steam supply side of the steam engine 2 are required to pass through the steam engine required for control based on the compressed air pressure on the discharge side of the compressor 3. When the amount of generated steam is less than the amount of steam used and less than the amount of steam used (the amount of steam generated <the amount of steam used).
In this case, the steam supply valve 8 is controlled based on the steam pressure on the steam supply side of the steam engine 2. More specifically, the generated steam on the steam supply side of the steam engine 2 is supplied to the steam engine 2 in its entirety. Further, on the exhaust steam side of the steam engine 2, steam to the steam utilization equipment is covered by steam from other steam systems (steam through a bypass valve), but the output M2 of the second controller 15 is almost the upper limit. Maintained at the value. On the other hand, in the third controller 16, the output M3 decreases in order to maintain the supply pressure to the steam engine 2, and the output of the third controller 16 among the outputs M1 to M3 from the three controllers 14 to 16. M3 becomes the minimum value, the output M3 of the third controller 16 is selected by the signal selector 17, and the opening degree of the steam supply valve 8 is adjusted based on the signal.

(5) The steam engine passage required for the amount of steam used on the exhaust side of the steam engine 2 and the amount of steam generated on the steam supply side of the steam engine 2 based on the compressed air pressure on the discharge side of the compressor 3 When the amount of steam used is less than the amount of steam generated and less than the amount of steam generated (the amount of steam used <the amount of steam generated).
In this case, the steam supply valve 8 is controlled based on the steam pressure on the exhaust steam side of the steam engine 2. More specifically, when the amount of steam passing through the steam engine exceeds the amount of steam used on the exhaust side of the steam engine 2, the detected pressure P2 of the second pressure sensor 12 increases, and the second pressure sensor 12 and the third pressure sensor Each of the 13 detected pressures P2, P3 increases. The pressure on the steam supply side of the steam engine 2 is adjusted by the amount of steam generated by the boiler 6 or the amount of steam discharged by the steaming valve, so that the output of the third controller is maintained almost at the upper limit. Further, the second controller 15 has an output that decreases in order to suppress an increase in the detected pressure of the second pressure sensor 12, and is the smallest among the outputs M1 to M3 from the three controllers 14 to 16, and the signal selector In 17, the output M2 of the second controller 15 is selected, and the opening degree of the steam supply valve 8 is adjusted based on the signal.

  As described above, according to the steam system 1 of the present embodiment, for example, when the amount of steam generated on the steam supply side of the steam engine 2 is insufficient, the control is switched to the control based on the steam pressure on the steam supply side, While maintaining the steam supply side pressure as desired, an amount of compressed air that can be discharged with the amount of steam supplied to the steam engine 2 is discharged. In addition, when the amount of steam used on the exhaust side of the steam engine 2 decreases, the control is switched to the control based on the steam pressure on the exhaust side, and compressed air that can be discharged with the amount of steam supplied to the steam engine 2 is thereby switched. Discharge. In this way, the control is automatically switched according to the situation to suppress the steam pressure decrease on the steam supply side of the steam engine 2 and the steam pressure increase on the exhaust steam side of the steam engine 2 while suppressing the steam. The steam engine 2 can be controlled within the limits of the amount of steam generated on the steam supply side of the engine 2 and the amount of steam used on the exhaust steam side of the steam engine 2. Furthermore, following the change in the amount of compressed air used, the steam engine 2 is not driven to produce compressed air. Therefore, it is possible to switch to the optimum control in consideration of the amount of compressed air used, the amount of steam used, and the amount generated.

  The steam system 1 of the present invention is not limited to the configuration of the above embodiment, and can be changed as appropriate. For example, in the above embodiment, the compressor 3 is driven by the steam engine 2, but a blower may be driven instead of the compressor 3. In that case, the same control as in the case of the compressor 3 can be performed.

  Moreover, in the said Example, the output M1-M3 of the 1st controller 14, the 2nd controller 15, and the 3rd controller 16 is received by the signal selector 17, and the steam supply amount to the steam engine 2 is the minimum (steam supply). Although the example which switches suitably to control in which the opening degree of the valve 8 is the minimum) was demonstrated, the 3rd controller 16 was abbreviate | omitted and the output M1, M2 of the 1st controller 14 and the 2nd controller 15 was a signal selector. You may make it switch to the control which receives in 17 and the steam supply amount to the steam engine 2 becomes the minimum.

  Further, in the above embodiment, the steam supply valve 8 is provided in the steam supply path 7 to the steam engine 2 and the opening degree is adjusted. However, instead of or in addition to this, to the steam engine 2 The steam supply path 7 and the steam path 9 from the steam engine 2 may be connected by a bypass path, and the opening degree of the bypass valve provided in the bypass path may be adjusted. Also in this case, the control by the first pressure sensor 11, the control by the second pressure sensor 12, and the control by the third pressure sensor 13 can be switched to the control that reduces the steam supply amount to the steam engine 2 as desired. That's fine.

1 Steam system 2 Steam engine (motor)
3 Compressor (driven machine)
4 unit 5 air path 6 boiler 7 steam supply path 8 steam supply valve 9 steam path 10 steam header 11 first pressure sensor 12 second pressure sensor 13 third pressure sensor 14 first controller 15 second controller 16 third control 17 Signal selector P1 Detection pressure of first pressure sensor P2 Detection pressure of second pressure sensor P3 Detection pressure of third pressure sensor M1 Output of first controller (opening setting signal of steam supply valve)
M2 Second controller output (steaming valve opening setting signal)
M3 Output of third controller (opening setting signal of steam supply valve)

Claims (8)

A prime mover that uses steam to generate power,
Driven by this prime mover and sucking and discharging fluid;
A first pressure sensor for detecting the pressure of the fluid on the discharge side of the driven machine;
A second pressure sensor for detecting the pressure of steam on the exhaust side of the prime mover,
When the detected pressure of the first pressure sensor rises, the steam supply amount to the prime mover is controlled based on the detected pressure of the first pressure sensor with a reverse operation type characteristic that reduces the steam supply amount to the prime mover, or When the detection pressure of the second pressure sensor rises, the steam supply amount to the prime mover is controlled based on the detection pressure of the second pressure sensor with a reverse operation type characteristic that reduces the steam supply amount to the prime mover,
A steam system, wherein the control is based on a control based on a pressure detected by the first pressure sensor and a control based on a pressure detected by the second pressure sensor, so that the amount of steam supplied to the prime mover is reduced. A third pressure sensor for detecting the pressure of steam on the steam supply side of the prime mover;
When the detected pressure of the first pressure sensor rises, the steam supply amount to the prime mover is controlled based on the detected pressure of the first pressure sensor with a reverse operation type characteristic that reduces the steam supply amount to the prime mover, or When the detection pressure of the second pressure sensor increases, the steam supply amount to the prime mover is controlled based on the detection pressure of the second pressure sensor with a reverse operation type characteristic that decreases the steam supply amount to the prime mover, or the first When the detected pressure of the three pressure sensors rises, the steam supply amount to the prime mover is controlled based on the detected pressure of the third pressure sensor with the characteristic of the positive action type that increases the steam supply amount to the prime mover,
Of the control based on the detection pressure of the first pressure sensor, the control based on the detection pressure of the second pressure sensor, and the control based on the detection pressure of the third pressure sensor, the amount of steam supplied to the prime mover is the largest. The steam system according to claim 1, wherein the control is switched to less control. The steam supply path to the prime mover is provided with a steam supply valve that adjusts the amount of steam supplied to the prime mover by adjusting the opening degree to adjust the output of the prime mover,
When the detected pressure of the first pressure sensor rises, the steam supply valve is controlled based on the detected pressure of the first pressure sensor with a reverse operation type characteristic that decreases the opening of the steam supply valve, or the second pressure When the detection pressure of the sensor rises, the steam supply valve is controlled based on the detection pressure of the second pressure sensor with a reverse operation type characteristic that reduces the opening of the steam supply valve, or the detection pressure of the third pressure sensor The steam valve is controlled based on the pressure detected by the third pressure sensor with a positive operating characteristic that increases the opening of the steam valve as
Of the control based on the detection pressure of the first pressure sensor, the control based on the detection pressure of the second pressure sensor, and the control based on the detection pressure of the third pressure sensor, the opening of the steam supply valve is the most. The steam system according to claim 2, wherein the control is switched to a smaller control. When the amount of steam used on the exhaust side of the prime mover and the amount of steam generated on the steam supply side of the prime mover are greater than the amount of steam passing through the prime mover required by the control based on the fluid pressure on the discharge side of the prime mover Controls the steam supply valve based on the fluid pressure on the discharge side of the driven machine,
The amount of steam used on the exhaust side of the prime mover is less than the amount of passing steam of the prime mover required in the control based on the fluid pressure on the discharge side of the driven device, but the amount of generated steam on the steam supply side of the prime mover is When the amount of steam passing through the prime mover required in the control based on the fluid pressure on the discharge side of the driven machine is greater than the steam pressure on the steaming side of the prime mover, the steam supply valve is controlled,
The amount of steam used on the exhaust side of the prime mover is greater than the amount of steam passing through the prime mover required for control based on the fluid pressure on the discharge side of the driven device, but the amount of steam generated on the steam supply side of the prime mover is In the case where the amount of steam passing through the prime mover required in the control based on the fluid pressure on the discharge side of the driven machine is smaller, the steam supply valve is controlled based on the steam pressure on the steam supply side of the prime mover,
The amount of steam used on the exhaust side of the prime mover and the amount of steam generated on the steam supply side of the prime mover are less than the amount of steam passing through the prime mover required by the control based on the fluid pressure on the discharge side of the prime mover, and When the generated steam amount <the used steam amount, the steam supply valve is controlled based on the steam pressure on the steam supply side of the prime mover,
The amount of steam used on the exhaust side of the prime mover and the amount of steam generated on the steam supply side of the prime mover are less than the amount of steam passing through the prime mover required by the control based on the fluid pressure on the discharge side of the prime mover, and The steam system according to claim 3, wherein when the amount of steam used is less than the amount of steam generated, the steam supply valve is controlled based on the steam pressure on the exhaust side of the prime mover. The driven machine is an air compressor;
The first pressure sensor detects a pressure in an air path from the air compressor to a compressed air utilization device or an air tank provided in the air path,
The second pressure sensor detects a pressure in a steam path from the prime mover to the steam utilization device or a steam header provided in the steam path,
The steam system according to any one of claims 2 to 4, wherein the third pressure sensor detects a pressure in a steam path from the boiler to the prime mover or a steam header provided in the steam path. In the air passage or the air tank, compressed air from a first air compressor driven by the prime mover and compression from a second air compressor driven by a driving source different from the first air compressor Air can be supplied,
The first air compressor is controlled to maintain the detected pressure of the first pressure sensor at a first set value in the control based on the detected pressure of the first pressure sensor,
The second air compressor is controlled to maintain the detected pressure of the first pressure sensor at a second set value;
The steam system according to claim 5, wherein the second set value is set lower than the first set value. The steam path or steam header from the prime mover to the steam utilization device can supply steam via the prime mover and steam via a bypass valve without going through the prime mover,
The prime mover is controlled to maintain the detected pressure of the second pressure sensor at a third set value in the control based on the detected pressure of the second pressure sensor,
The opening degree of the bypass valve is adjusted to maintain the detected pressure of the second pressure sensor at a fourth set value,
The steam system according to claim 5 or 6, wherein the fourth set value is set lower than the third set value. The amount of steam supply to the prime mover is controlled to maintain the detection pressure of the third pressure sensor at a fifth set value in the control based on the detection pressure of the third pressure sensor,
The boiler is controlled to maintain the detected pressure of the third pressure sensor at a sixth set value, or an evaporating valve provided on the upstream side of the prime mover controls the detected pressure of the third pressure sensor to the sixth The opening is adjusted to maintain the set value,
The steam system according to any one of claims 5 to 7, wherein the sixth set value is set higher than the fifth set value.

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