JPWO2017130303A1 - Gas compressor and gas compressor system - Google Patents

Abstract

  The gas compressor generates regenerative electric power using the gas exhausted from the gas compressor and other devices. A gas compressor having a compressor body that sucks in gas and generates compressed gas, and is an electric motor that receives supplied electric power and drives the compressor body, and obtains power from the compressor body to generate regenerative electric power. A rotating electrical machine to be a generator to be generated, an inverter to control the rotational speed of the rotating electrical machine by changing the frequency of the supplied power, a converter to generate output power from the generated power, and discharge of a compressor body The side piping has a check valve for permitting the flow of compressed air from the compressor body side to the discharge side on the side piping, and when the drive of the compressor body is stopped, the compressor air upstream from the check valve is backflowed A gas compressor which generates power for generating the regenerated electric power by reverse rotation of the compressor body.

Description

  The present invention relates to a gas compressor and a gas compressor system, and more particularly to a gas compressor and a gas compressor system for regenerating energy.

  It is said that the energy consumed by gas compressors, such as an air compressor, is equivalent to 20 to 25% among the energy consumed by the whole factory etc., and the effect to energy saving of a gas compressor is large.

  In recent years, as a matter of course, the gas compressor device itself has high performance, and in addition to energy saving from the drive control surface using an inverter for a gas (for example, air) compressor, exhaust heat generated during compression is recovered and heated Efforts have also been made to use it for water, to use hot water, and to use preheated boiler water.

  Further, in Patent Document 1, heat is exchanged between heat of high-temperature compressed air discharged from a gas compressor main body and lubricating oil performing lubrication of the gas compressor main body, cooling of a compressed gas, and the like, and power generation is performed by a Rankine cycle. Disclose.

  In addition, the electric motor (motor) used as a drive source which drives a gas compressor main body is a rotary electric machine which functions as a generator (generator) by reversing. Patent Document 2 discloses a positive displacement screw expander as a steam expander (expander) for expanding steam as a means for reversing a motor. Patent Document 2 discloses a configuration in which expansion of steam supplied from a steam supply system such as a boiler is converted into rotational force by a screw expander and this is used as a drive source of a generator.

JP 2011-12659 A Patent No. 5148117 gazette

  Generally, as a gas compressor, a variable speed controller equipped with an inverter to control the motor at variable speeds and a constant speed controller operating the motor at a constant speed are known. From the energy saving point of view, in capacity control of the constant speed controller, load / unload operation control that repeats load operation and no-load operation according to the amount of gas used by the user etc., and automatic stop control etc. is there. On the other hand, in the capacity control of the variable speed controller, energy saving can be achieved by variable speed control using an inverter in addition to these.

  In such control, the compressed gas in the compressor internal piping system is discharged to the atmosphere and decompressed during unloading operation or automatic stop, and the energy saving effect is obtained by reducing the load of the motor as the driving source. .

  However, since the compressed gas released is discarded, if the aerated gas can be effectively used in this respect, it leads to energy saving of the gas compressor.

  In order to solve the above problems, for example, the configuration described in the claims is applied. That is, it is a gas compressor having a compressor main body that sucks in gas and generates compressed gas, which is an electric motor that receives supplied electric power and drives the compressor main body, and obtains power from the compressor main body to generate regenerative electric power. A rotary electric machine serving as a generator for generating the electric power, an inverter for controlling the rotational speed of the rotary electric machine by changing the frequency of the supplied electric power, a converter for generating output electric power from the generated electric power, and The compressor has a check valve for permitting the flow of compressed air from the compressor body side to the discharge side on the discharge side piping, and when the drive of the compressor body is stopped, the compressor air upstream from the check valve is It is a gas compressor which reversely rotates the said compressor main body by backflowing, and produces | generates the motive power which produces | generates the said regeneration electric power.

  Further, another configuration is a gas compressor system comprising a plurality of gas compressors having a compressor body that sucks in gas and generates compressed gas, wherein at least one gas compressor of the plurality of gas compressors A is a motor that receives supplied power to drive the compressor body, and a rotating electrical machine that serves as a generator that receives power from the compressor body to generate regenerative power, and changes the frequency of the supplied power to change the frequency of the supplied power Permits the flow of compressed air from the compressor body to the discharge side on the inverter that controls the rotational speed of the rotating electrical machine, the converter that generates output power from the generated electric power, and the discharge side piping of the compressor body And an external intake pipe communicating with the discharge pipe path from the discharge side of the compressor body to the upstream of the check valve and taking in compressed air from one or more other gas compressors B And the above The compressor main body is reversely rotated by the compressor air taken in from the external intake pipe at the time of operation standby of the main body of the compressor, to generate power to generate the regenerative electric power, and the gas compressor B generates the motive power. An electric motor for driving the compressor body, a check valve for permitting the flow of compressed air from the compressor body side to the discharge side on the discharge side piping of the compressor body, and compressed air upstream from the check valve And an air release valve installed on the air release pipe, and the gas compressor system includes a portion downstream of the air release valve of the gas compressor B and the gas compressor. The external intake piping of A is in communication, and is communicably connected to the plurality of gas compressors, and the gas compression A is on standby for operation and when the gas compressor B is degassing, Gas compressor system having a control device for opening A.

  According to one aspect of the present invention, the gas compressor that generates compressed gas can also be used as an apparatus that generates regenerative energy using excess gas, and the energy saving effect is improved.

Further, according to one aspect of the present invention, in the gas compressor system including a plurality of gas compressors, regenerative energy can be generated by the other gas compressor using the aeration gas of the one gas compressor. Can save energy in the whole system.
Other problems, configurations and effects of the present invention will become apparent from the following description.

It is a schematic diagram which shows the structure of the air compressor by Example 1 to which this invention is applied. 5 is a timing chart showing the flow of the operation of the air compressor according to the first embodiment. It is a schematic diagram which shows the structure of the air compressor system by Example 2 to which this invention is applied. 10 is a flowchart showing the flow of processing of a number control unit according to a second embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 schematically shows the structure of a refueling air compressor 100 according to an embodiment of the present invention. In the present embodiment, a refueling type air compressor that sucks in air and discharges compressed air is illustrated, but the present invention is not limited to this, and the type and supply of gas to be compressed without departing from the scope It can also be applied to a liquid (water etc.) type compression device.

  The air compressor 100 includes a compressor main body 5 that compresses air taken in through the air filter 1 and the suction throttle valve 2 from the outside, a rotary electric machine 6 serving as a drive source and power generation source for the compressor main body, and discharge mixing. A temperature sensor for detecting the temperature of the gas, an oil separator 9 for primary separation of compressed air and lubricating oil from the discharged mixed gas, an element 10 for secondary separation of oil from the separated compressed air, and A pressure adjustment check valve 11 disposed on a discharge piping path of the compressed air, a heat exchanger 13 for cooling the compressed air flowing through the check valve 11 and a lubricating oil described later by a cooling air from a fan 14; Unlike the above-described discharge piping, a control piping system disposed on the downstream side of the oil separator 9, and an air discharge solenoid valve 17, an operation solenoid valve 18, and regeneration that are respectively disposed on three pipes branched from the air discharge piping system. Solenoid valve 19 and regenerative A jet valve 3 disposed downstream of the valve 19, a jet element 4 disposed downstream of the jet valve 3, and a recovery mechanism (oil) that returns the lubricating oil removed by the jet element 4 to the compressor body 5 (oil Control panel 27 for controlling the rotary electric machine 6, the fan motor 15, various solenoid valves, etc., a fan inverter 16 for frequency conversion of the power supplied to the fan motor 15, and the like And an external housing (package) 23 for storing the data as main components.

  The compressed air generated by the air compressor 100 is temporarily stored in the external tank (reservoir tank) 45 and then sent to the device on the user side. The compressed air may be directly sent to the user-side device without installing the external tank 45.

  The compressor body 5 is a screw type compressor comprising one or more screw rotors. The rotor and the motor shaft of the compressor body 5 and the rotary electric machine 6 are configured to be coaxial (in a divided or integral configuration). By being the same as the axis, opportunity loss can be reduced, which contributes to efficient compression and efficient power generation. The present invention can also be applied to other types of compressor bodies and other connection configurations.

  The oil separator 9 has a lubricating oil passage 30 for returning the lubricating oil accumulated at the bottom to the compressor body side. The lubricating oil passage 30 is branched at its downstream side into two systems via the temperature control valve 12 on the way. One is a reflux path directly in communication with the compressor body 5 and the other is a path connected to the reflux path after passing through the heat exchanger 13. The temperature control valve 12 is a valve that switches the lubricating oil flow path with the lubricating oil temperature as the threshold, and opens the path directly returning to the compressor body 5 when the lubricating oil temperature is lower than the threshold, If it is higher than the threshold, the path connected to the heat exchanger 13 is opened to switch the flow path. For example, if the discharge air temperature is lower than the drain generation limit temperature immediately after start-up, etc., lubricating oil is circulated in a path not flowing into the heat exchanger 13 to raise the discharge temperature in order to prevent generation of drain. . Conversely, when the temperature is higher than the drain generation limit temperature, in order to prevent the discharge temperature from rising further, the path is switched to the path flowing into the heat exchanger 13. The lubricating oil that has flowed through any of the paths then flows back to the compressor body 5 via the oil filter 20.

  The heat exchanger 13 is a cooler that exchanges the separated compressed air and lubricating oil with the cooling air generated by the fan 14. According to the detection value of the temperature sensor 25 that detects the temperature of the discharge air discharged from the compressor main body 5, the control unit 26 changes the number of rotations of the cooling fan by the fan inverter 16 and the fan motor 15. It has become.

  A control piping system 31 which is connected to the downstream side of the element 10 for secondary separation of the lubricating oil and which is a route different from the discharge piping system leading to the user side is an air discharge path of compressed air to the outside, a suction throttle valve 2 and It functions as a path for supplying the drive control pressure of the ejection valve 3.

  When the driving of the compressor main body 5 is in the unloading operation, the air discharging solenoid valve 17 discharges the pressure of the compressed air between the pressure adjusting check valve 11 and the compressor main body 5 to reduce the pressure, and the driving of the rotary electric machine 6 It is designed to reduce power. More specifically, the control unit 26 "closes" the operation solenoid valve 18 and the regeneration solenoid valve 19 and "opens" the air release solenoid valve 17 to perform external air discharge.

  The operation solenoid valve (suction throttle valve control device) 18 is “opened” during the load operation, the suction throttle valve 2 is opened, and the outside air is taken into the compressor body 5. Further, the operation solenoid valve 18 is “closed” when the compressor body 5 is in the automatic stop operation, and the suction throttle valve 2 having an urging force in the closing direction is closed by a spring or the like. Prevent the circulation of outside air. The control unit 26 controls the opening and closing of the operation control valve 18.

  The regeneration solenoid valve (valve body control device) 3 is "closed" in the load operation or the unload operation, and as a result, the ejection valve 3 prohibits the communication between the ejection element 4 side and the intake path. . In the case of the automatic stop operation, the regeneration solenoid valve 3 is “opened”, and the ejection valve 3 permits communication between the ejection element 4 side and the intake path. The control unit 26 controls the opening and closing of the regeneration solenoid valve 3.

  The suction piping path through which the air sucked through the suction throttle valve 2 flows to the compressor body 5 is divided into two in the middle, one is connected to the compressor body 5 and the other is for ejection (oil) It is connected to the element 4 and the oil recovery mechanism. The air flow to the other path is controlled by the regeneration solenoid valve 3 as described above. Since the compressed air flowing backward from the suction side of the compressor main body 5 is a mixed gas of air and lubricating oil during regeneration operation using the aeration air described later, an oil recovery mechanism is provided inside or outside of the lubricating oil casing To prevent it from being

  The oil recovery mechanism includes an oil receiver 40 and a check valve 41. The squirting element 4 separates oil and air from compressed air flowing backward from the side of the compressor main body 5 during regenerative operation, and the separated oil is separated via an oil receiver 40 and a check valve 41 installed at the drop destination. And return to the suction piping path. At the time of regenerative operation, the suction piping path side becomes high pressure, and oil does not reflux from the upstream side of the check valve 41, but the regenerative piping ends and the air compression operation returns to negative pressure, and the suction piping path side becomes negative pressure. Reflux of lubricating oil is permitted to the system.

  The control unit 26 is a control function unit realized by the cooperation of an arithmetic device such as a CPU or an MPU and a program, and outputs various control commands to the solenoid valve, the inverter 7, the converter 8 and the fan inverter 16. . Further, the control unit 26 includes a memory (not shown), and can store or set an air discharge pressure, various control thresholds, and the like externally input through an operation panel or a network (not shown).

  The air compressor 100 has a pressure sensor 28 as a pressure detection device on the user-side discharge piping path downstream of the pressure regulating valve 11. The pressure sensor 28 detects the pressure of compressed air at the user side (equipment machine, reservoir tank, etc.). The control unit 26 outputs a control command to the inverter 7 according to the detection value of the pressure sensor 28, and executes inverter control operation, load operation, unload operation and automatic stop operation.

  Here, the inverter control operation is control for changing the output frequency value of the inverter based on the detection value of the pressure sensor 28 so that the discharge pressure on the user side maintains a predetermined set discharge pressure. For example, when the user side discharge pressure becomes equal to or higher than the set pressure, the output frequency is reduced to reduce the number of rotations of the compressor main body 5. Conversely, when the pressure is lower than the set pressure, the output frequency is increased to increase the number of revolutions of the compressor body 5.

In the unloading operation, for example, when the air consumption on the user side decreases and the user side pressure reaches a predetermined upper limit pressure higher than the set discharge pressure, the aeration solenoid valve 17 is opened and the operation electromagnetic The valve 18 is set to “close”, and the rotational speed of the rotary electric machine 6 is further reduced to save energy for driving the compressor body 5. As the degree of reduction of the rotational speed, for example, the rotational speed of the lowest degree that generates the pressure necessary for the lubricating oil to flow through the lubricating oil path 30 can be mentioned, but it is not limited thereto. Although the suction throttle valve 2 is “closed”, the discharge side of the compressor main body 5 can generate an environment having a pressure higher than the atmospheric pressure by the air slightly sucked in from the valve closing gap or the like.
Thereafter, when it is detected that the user's air use amount has decreased to the vicinity of the set discharge pressure, etc., the air release solenoid valve 17 is closed, and compression resumes on the upstream side of the pressure adjustment check valve 11 or In addition to this, the rotational speed of the rotary electric machine 6 is increased, and the user side is maintained above the set discharge pressure with the upper limit pressure as a limit. When the pressure on the user side drops to a predetermined lower limit pressure lower than the set discharge pressure, it is preferable to switch to the load operation.

  The load operation is an operation of driving the rotary electric machine 6 at a rated rate by maintaining the air release valve 17 in the “close” state and the operation solenoid valve 17 in the “open” state until the set discharge pressure is reached. The present invention is applicable even when the suction throttle valve 2 and the operation solenoid valve 16 are not included in the configuration.

  The automatic stop operation is an operation for temporarily stopping the driving of the compressor main body 5 when the amount of air used on the user side decreases and the state where the user side pressure exceeds the set discharge pressure continues for a predetermined period of time etc. . For example, when the amount of air used on the user side decreases and the pressure on the user side exceeds the set discharge pressure and eventually reaches the upper limit pressure, the control unit 26 executes the above unloading operation, but the unloading operation is performed. The drive of the compressor body 5 is temporarily stopped (power supply to the rotary electric machine 6 is stopped) rather than continuing the operation for a long time, and the lapse of a predetermined time or the user side pressure is a predetermined pressure (for example, lower limit in unload operation) When it becomes lower than the return pressure lower than the pressure, etc., it may be more efficient in terms of energy saving to re-drive.

  So, in a present Example, if the state more than setting discharge pressure continues for a predetermined time, the electric power supply to the rotary electric machine 6 will be stopped, and electric power will be saved. The pressure reference for starting the automatic stop operation is not limited to the set discharge pressure, but may be any pressure such as the upper limit pressure. Further, the duration of the predetermined pressure state is not limited to the start trigger of the automatic stop operation, and the control unit 26 monitors and calculates the ratio of the unload operation and the load operation per unit time interval, and the ratio of the unload operation Various aspects may be applied, such as executing an automatic stop operation when the value of L increases. Furthermore, although an example in which the unloading operation is performed before the automatic stop operation is described in the embodiment, the present invention can be applied without necessarily assuming the unload operation as the automatic stop operation.

Next, the regenerative operation function will be described with reference to FIG.
As described above, the rotation of the compressor main body 5 is temporarily stopped (the power supply to the rotary electric machine 6 is stopped) during the automatic stop operation, but on the discharge side of the compressor main body 5 downstream from the pressure adjustment check valve 11 On the other hand, back pressure is generated by backflow. During unloading operation, the back pressure is eliminated by discharging air to the outside through the air release solenoid valve 17. However, when the regeneration operation is performed, the air release solenoid valve 17 is closed and the downstream side from the pressure adjustment check valve 11 The compressed air of the above is made to flow back to the compressor body 5. The screw rotor of the compressor main body 5 is reversely rotated by the backflowing compressed air, and the rotary electric machine 6 is also reversely rotated along with this, thereby functioning as a generator. The electricity generated by the reverse rotation of the rotary electric machine 6 can be used by the converter 8 as regenerative electric power. As described above, the compressed air discharged from the suction side of the compressor body 5 to the suction pipe path thereafter is exhausted to the outside of the pipe system.

  The regenerative power is used as the power of the fan motor 15 for driving the cooling fan 14. Since the regenerative electric power is generated using the aeration air, it is equivalent to the absence of the compressed air generated by the compressor body 5 at the time of the automatic stop operation and the like. The number of rotations of the cooling fan may be relatively low because the lubricating oil is also less likely to rise. For this reason, the generated power can be generated only during the release of the aeration air, but sufficient power can be obtained when a low load cooling environment is sufficient.

  In this embodiment, although an example of using as electric power for a fan motor will be described, the present invention is not limited to this, and a storage battery for backup power source etc. is provided inside the compressor 100, variously for charging etc. Configuration is possible.

The flow of such a series of operations will be described.
At time t0, the rotary electric machine 6 is driven at the rated speed, and the pressure on the user side indicates the set discharge pressure. The load factor of the rotary electric machine 6 at this time is 100% (rated), the operation solenoid valve 18 is "open (ie, the suction throttle valve 2 is open)", the air release solenoid valve 17 is "closed", for regeneration The load operation (in the inverter control operation) is performed with the solenoid valve 19 in the "closed" state. In the drawing, the “rotation direction” is the rotation direction of the rotary electric machine 6, and the rotation direction at the time of compression is “forward rotation”.

  When detecting that the user side discharge pressure has reached the upper limit value at time t1, the control unit 26 starts the unloading operation. That is, a frequency reduction instruction (for example, the minimum rotational frequency) is output to the inverter 7 to reduce the load factor of the rotary electric machine 6. Similarly, the control unit 26 "closes" the operation solenoid valve 18 and "opens" the air release solenoid valve 17 to restrict the intake of air and reduce the pressure in the piping system upstream from the pressure adjustment check valve 11. . Thereby, the load factor of the rotary electric machine 6 is further reduced. Thereafter, the user side discharge pressure gradually decreases in accordance with the amount of air used on the user side.

When it is detected that the user side discharge pressure has reached the lower limit value set to the same value as the set discharge pressure at time t2, the control unit 26 switches from the unload operation to the load operation. The load operation at this time is a load operation performed by controlling the air release solenoid valve and the operation control valve while the load factor of the rotary electric machine 6 is reduced.
The control unit 26 “opens” the operation solenoid valve 18 and “closes” the air release solenoid valve 17 to pressurize the piping system upstream from the pressure adjustment check valve 11. That is, the rotation at a low load rate of the rotary electric machine 6 is used to increase the suction amount and to limit the air discharge amount to increase the pressure.

  When detecting that the user side discharge pressure has reached the upper limit value at time t3, the control unit 26 "closes" the operation solenoid valve 18 and "opens" the air release solenoid valve 17 again. That is, the operation state is the same as the unloading operation at time t1. At time t4, when the control unit 26 detects that the user side discharge pressure has reached the lower limit again, the solenoid valve is controlled to increase the pressure again as at time t3. In the present embodiment, the trigger for switching from the unloading operation to the loading operation will be described as the upper limit pressure, but any pressure between the set discharge pressure and the upper limit pressure may be used as the trigger for switching. . This is because when the set value of the upper limit pressure is relatively high, it may take a significant amount of time to raise the pressure in the unloading operation.

  As described above, the air compressor 100 repeats the unloading operation and the loading operation based on the user side discharge pressure, but the control unit 26 operates the timer simultaneously with the detection of the upper limit pressure, and then, the lower limit pressure is set. If the elapse of a predetermined time or the like is detected before reaching, execution of the automatic stop operation is started.

  When a predetermined elapsed time is detected at time t5, the control unit 26 raises the user-side discharge pressure to the upper limit value by setting the operation solenoid valve 18 "open" and the air release solenoid valve 17 "close". At this time, the rotational speed of the rotary electric machine 6 may be increased if necessary. That is, before stopping the compressor main body 5, control is performed to increase the user-side pressure. The automatic stop function occurs when the user's air usage amount is very small or not for a predetermined elapsed time. For example, high-pressure compressed air filled in the reservoir tank or user equipment is cooled by natural heat radiation or the like. If so, drain may occur. There is also an advantage that when the user starts using again, a pressure higher than the set discharge pressure can be obtained immediately. Furthermore, since the inside of the piping system of the air compressor 100 becomes substantially atmospheric pressure by the automatic stop operation, it takes time to obtain the pressure up to the set discharge pressure, etc. even if the air usage amount is increased and redriven. It depends on the reason.

At time t6, when the control unit 26 executes repressurization to the upper limit pressure, the operation solenoid valve 18 is closed, but the air release solenoid valve 17 is maintained closed. Then, after setting the operation solenoid valve 18 to “close”, the regeneration solenoid valve 19 is set to “open”. As a result, compressed air flows back from the piping system upstream from the pressure adjustment check valve 11 to the discharge side of the compressor main body 5, and power generation by the rotary electric machine 6 is started. By setting the regenerating solenoid valve 19 to “open” after “closing” the operation solenoid valve 18 (several seconds), the reverse flow compressed air containing a relatively large amount of oil is drawn into the intake throttle valve 2 or its upstream side. It can be reliably prevented from circulating.
After the automatic stop operation, the load operation (by the inverter control operation) is resumed with a predetermined elapsed time or an arbitrary redrive start pressure as a trigger.

  In the present embodiment, the control mode for performing the unloading operation has been described. However, even if there is no unloading operation and the mode is the combination control of only the inverter control operation and the automatic stop operation, the rotation operation is performed in the automatic stop operation. If the reverse of the electric machine 6 is possible, it is applicable. Further, in the present embodiment, an example has been described in which the automatic stop operation is performed by boosting up to the upper limit value before the stop, but it is equally possible to configure so as to discharge air without boosting.

As described above, according to the present embodiment, it is possible to obtain regenerative electric power by using air to be discharged (discarded). Furthermore, since the compressor body itself is used for the compression means and the expansion means, and the rotary electric machine is used for the motor and the generator, the applicability as a device is significantly enhanced.
Further, in the present embodiment, boosting is performed before the automatic stop operation from the viewpoint of user-side drain generation prevention and usability at the time of resuming use of air. However, power can be further obtained using this boosted pressure. Demonstrates excellent effects on convenience as a aircraft and reduction of energy loss.
Further, the valve control on the suction pipe path side accompanying the regenerative operation prevents oil from being scattered to the inside or the surrounding external environment of the external housing 23, and also has effects of maintenance and environment.

  The first embodiment is an example in which the regenerative electric power is generated by causing the compressed air in the air compressor 100 to flow back to the compressor main body 5, but the second embodiment uses the aeration air of another air compressor. Power generation. Example 2 will be described below with reference to the drawings. The same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description is omitted.

  The structure of the air compressor system 300 by Example 2 is typically shown in FIG. The air compressor system 300 includes the air compressor 100 of the first embodiment and an air compressor 200. The air compressor system 300 is, for example, a compressor system capable of controlling a plurality of machines in accordance with the amount of used air. Both units are driven and one is driven and the other is stopped under control of the number control unit 50 connected by wire or wireless (including network connection such as the Internet) communicably with the respective control units 26A, 26B (the compressor It is possible to perform various operations such as a standby state in which the main body 5 stops driving, or both stops.

  The number control unit 50 is realized by the cooperation of an arithmetic device such as a CPU or an MPU and a program. In the present embodiment, the number control unit 50 is installed outside the air compressors 100 and 200. However, the number control unit 50 may be mounted on the control panel 27 or the like of any air compressor.

  The main difference between the air compressor 100 and the first embodiment is that the aeration air for taking in the aeration air of the air compressor 200 into the discharge piping connected from the compressed air main body 5 to the oil separator 9. It is a point provided with intake piping (external intake piping) 22. The aeration air intake pipe 22 is provided with a three-way solenoid valve 60, and when the air compressor 100 is in an unloading operation, an automatic stop operation, or the like (when the regeneration operation can not be performed), It prohibits the intake of the aeration air and permits the circulation to the route of the outside aeration side. When the three-way solenoid valve 60 is in a state where the regenerative operation is possible, it prohibits the circulation of the external air discharging side, and permits the intake of the air discharging air from the air compressor 200.

  The air compressor 200 is a refueling screw compressor. The respective components for generating compressed air are the same as those of the air compressor 100, but the elements for generating regenerative power (converter 8, solenoid valve 19 for regeneration, converter 8, oil recovery mechanism, etc.) are not provided. Here, the air compressor 200 is also provided with a circuit power generation element, and the air discharge pipes of the air compressors 100 and 200 can be used to connect the air discharge pipe and the intake pipe to each other so that any air can be compressed. You can also make it possible to generate electricity.

  The air compressor 200 is not limited to the air compressor 200, which is an oil-feeding screw compressor, and may be another oil-feeding or oil-free compressor such as a vane, a scroll, or a reciprocating machine.

  The air discharge piping system of the air compressor 200 is connected to the air discharge air intake pipe 22 of the air compressor 100. For example, when the air compressor 200 is driven and the air compressor 100 is in a stop (standby) state, the compressor body 5 of the air compressor 100 is in a state in which reverse rotation is possible. Therefore, the air compressor 200 discharges the aeration air during the unloading operation and the automatic stop operation to the air compressor 100 side, and the air compressor 100 generates power. In the first embodiment, only the aeration at the time of the automatic operation can execute power generation, but the second embodiment has a specific effect that the aeration at the unloading operation can also be used.

  In the second embodiment, the compressed air generated by the air compressor 100 is temporarily stored in the external tank 45A as in the first embodiment. The compressed air generated by the air compressor 200 may be temporarily stored in the external tank 45A or may be stored in another external tank 45B. Furthermore, compressed air may be supplied directly to the user side device without using an external tank.

  In such a configuration, the aeration air intake pipe 22 of the air compressor 100 may be connected to the external tanks 45A and 45B and the user-side device. By regenerating these surplus compressed airs, more regenerative power can be obtained. In particular, the compressed air temporarily stored in the external tank 45B may discharge stored air, for example, when one day's use is finished. For example, if the time until reuse is long, if the pressure remains high, the temperature may cause drainage in the tank.

  FIG. 4 shows the process flow of the air compressor system. The present process is executed by the number control unit 50 and the control units 26A and 26B of the air compressors 100 and 200.

  In S101, the number control unit 50 determines whether the driving of the air compressor 100 is stopped or in operation standby and the air compressor 200 is in driving operation (including load operation and unloading operation), and so on. If there is (S101: Yes), the process proceeds to S103, the three-way solenoid valve 50 is set to "open", and the aeration piping system of the air compressor 200 and the discharge of the air compressor 100 via the aeration air intake piping 22. Connect the side piping. When the air compressor 100 is in driving operation (S101: No), the process proceeds to S108, and the three-way solenoid valve 60 is set to "close" so that the aeration air from the air compressor 200 flows in the external aeration pipe. .

At S105, the unit number control unit instructs the control unit 26A to "close" the aeration solenoid valve 17 of the air compressor 100, "close" the operation solenoid valve 18, and "open" the regeneration solenoid valve 19. . Thereafter, air discharge is performed by unloading operation or automatic stop operation of the air compressor 200, the rotary electric machine 6 of the air compressor 100 is reversely rotated, and power generation is performed. The generated power is sent to the air compressor 200 via the converter 8

At S107, the control unit 26B causes the electric power sent from the air compressor 100 to be sent to the fan motor inverter 16 to use it as regenerative energy.

  As described above, according to the second embodiment, the power can be generated by using the aeration air of another air compressor. Further, in the case of regeneration with an air compressor alone, power can be generated only by the aeration air at the time of automatic stop operation, but in the case of the second embodiment, the aeration air at the unloading operation of other air compressors is used. be able to.

  Although the regenerative electric power is used as the fan electric power of the air compressor 200 in the second embodiment, the regenerative electric power can also be used for other applications as in the first embodiment.

As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to said various Example, A combination and omission are possible in the range which does not deviate from the meaning.
For example, in the second embodiment, although the regenerative power generated by the air compressor 100 is used for the fan power of the air compressor 200, the regenerative power is used as a (re) starting auxiliary power supply for the air compressor 100. It may be used for charging the battery.

  In the second embodiment, power generation is performed only by the air compressor 100. However, the air compressor 200 also has a similar power generation mechanism, and the air discharge piping system of each other is used as the other air discharge air intake piping. It is possible to mutually connect the two and exchange roles between the two in accordance with the operating conditions to generate power. For example, from the viewpoint of securing the life of the device, in the case of a control mode in which driving and stopping are alternately repeated so that the driving time of a plurality of compressors is smoothed, the aeration air of both can be used for power generation.

  Further, in the second embodiment, when the excess compressed air of the external tanks 45A and 45B and the user side device is used for regeneration, the pressure control check valve 11 is used. A pipe for bypassing and a valve body for permitting and prohibiting the flow thereof may be provided, and the aeration air of the external tank or the like may be reversely flowed from the discharge side.

  Furthermore, in the second embodiment, although the line power is obtained by electric and electronic control by the number control unit 50 or the like, the air compressor main body 100 is not spared, not a compressor system in which a plurality of units cooperate to drive and stop. The air compressor may be used generally only as a power generation device, and may be used as an air compressor as required.

DESCRIPTION OF SYMBOLS 1 ... Suction filter, 2 ... Suction throttle valve, 3 ... Ejection valve, 4 ... Ejecting element, 5 ... Compressor main body, 6 ... Rotation motor, 7 ... Inverter for rotation motor, 8 ... Power regeneration converter, 9 ... Oil separator, 10 ... element, 11 ... pressure adjustment check valve, 12 ... temperature adjustment valve, 13: heat exchanger (oil cooler / after cooler), 14 ... cooling fan, 15 ... fan motor, 16 ... for fan motor Inverter, 17: Air release solenoid valve, 18: Operation solenoid valve, 19: Regeneration solenoid valve, 20: Oil filter, 21: Oil receiver and recovery path, 22: Air release air intake piping, 23: External housing (package 25) Temperature sensor 26 26 A 26 B control unit 27 control panel 28 pressure sensor 30 lubricating oil path 31 control piping path 41 oil receiver 42 check valve 45 · 45A · 45B ... outside Link (reservoir tank), 50 ... count control unit, 60 ... three-way solenoid valve 100-200 ... air compressor 300 ... air compressor system

Claims (17)

What is claimed is: 1. A gas compressor having a compressor body that sucks in gas and generates compressed gas, comprising:
A rotating electric machine which is an electric motor for receiving the supplied electric power and driving the compressor body and which serves as a generator for obtaining regenerative electric power by obtaining power from the compressor body;
An inverter that changes the frequency of the supplied power to control the rotational speed of the rotating electrical machine;
A converter that generates an output power from the generated power;
A check valve for permitting the flow of compressed air from the compressor body side to the discharge side on the discharge side piping of the compressor body;
The compressor body is reversely rotated by the backflow of the compressor air upstream from the check valve when the driving of the compressor body is stopped, so that the motive power for generating the regenerative power is generated. A gas compressor according to claim 1, wherein
The gas compressor, wherein the compressor body is a liquid supply type, and has a gas-liquid separator downstream of the compressor body and upstream of the check valve. The gas compressor according to claim 2, wherein
A suction throttle valve which is installed on the intake path of the compressor body and which permits and prohibits the flow of the intake gas by opening and closing;
A suction throttle valve control device for controlling the opening and closing of the suction throttle valve;
A jet pipe path branched from the intake path downstream of the suction throttle valve and between the compressor main bodies;
A valve body which permits and prohibits the communication between the intake passage and the jet piping passage by opening and closing;
A valve control device for controlling the opening and closing of the valve;
And an oil element downstream of the jet piping path,
A gas compressor, wherein the suction throttle valve control device closes the suction throttle valve and the valve body control device opens the valve body when driving of the compressor body is stopped. A gas compressor according to claim 3, wherein
The gas compressor, wherein the suction throttle valve control device is an electromagnetic valve installed on a pipe path connecting the gas-liquid separator and the suction throttle valve. A gas compressor according to claim 3, wherein
The gas compressor, wherein the valve body control device is a solenoid valve installed on a pipe path connecting the gas-liquid separator and the valve body. A gas compressor according to claim 3, wherein
A gas compressor having an oil recovery mechanism which recovers the lubricating oil recovered by the oil element and refluxes it to the compressor body. A gas compressor according to claim 1, wherein
A pressure detection device that detects a discharge side pressure downstream of the check valve;
It has a control part which controls the said inverter based on the detection pressure of the said pressure detection apparatus,
The said control part is a gas compressor which makes said inverter stop a drive of said compressor main body, when said detection pressure reaches predetermined pressure. The gas compressor according to claim 7, wherein
A gas compressor, wherein the control unit stops the compressor body after the discharge side pressure is increased to at least the predetermined pressure. A gas compressor according to claim 8, wherein
A gas compressor, wherein the control unit causes the rotating electrical machine to be redriven as a motor after a predetermined time has elapsed after stopping the driving of the compressor body or when the discharge side pressure detects a predetermined pressure. The gas compressor according to claim 7, wherein
It has an air release pipe for discharging compressed air upstream of the check valve, and an air release valve installed on the air release pipe,
When the control value of the pressure detection device reaches a predetermined pressure, the control unit rotates the rotational speed of the rotary electric machine at a rotational speed smaller than the rated speed and opens and closes the discharge side pressure within a predetermined pressure range by opening and closing the air release valve. A gas compressor that is intended to perform an unloading operation to maintain. A gas compressor according to claim 10, wherein
When the control unit detects that the predetermined time has elapsed before the detection value of the pressure detection device reaches the lower limit pressure of the predetermined pressure range after closing the air release valve in the unloading operation. A gas compressor for stopping driving of the compressor body. A gas compressor according to claim 1, wherein
An external intake pipe communicating with a discharge pipe path from the discharge side of the compressor body to the upstream of the check valve and taking in compressed gas from the outside;
A valve body for permitting and prohibiting communication between the discharge pipe and the external intake pipe;
The said control part is a gas compressor which permits communication of the said discharge piping and external intake piping at the time of the drive stop of the said compressor main body. The gas compressor according to claim 12, wherein
It has an air release pipe which branches from the external intake pipe and communicates with the outside,
The valve body which permits and prohibits the communication between the discharge piping and the external intake piping permits only the communication between the discharge piping and the external intake piping, and permits only the communication between the external intake piping and the aeration piping. It is a three-way valve that switches
The said control part is a gas compressor which permits only said communication of the said external intake piping and the aeration piping at the time of the drive of the said compression main body. The gas compressor according to claim 12, wherein
A gas compressor, wherein the compressed gas taken in from the external intake pipe is supplied from another gas compressor. The gas compressor according to claim 14, wherein
The gas compressor in which the compressed gas taken in from the external intake pipe is an aeration gas due to unloading operation or stop of operation of another gas compressor.   The gas compressor according to claim 12, wherein the compressed gas taken in from the external intake pipe is an external tank for storing compressed air generated by the gas compressor. What is claimed is: 1. A gas compressor system comprising a plurality of gas compressors having a compressor body that sucks in gas and generates compressed gas, comprising:
At least one gas compressor A of the plurality of gas compressors is a motor that receives the supplied electric power and drives the compressor body, and a rotation that becomes a generator that obtains power from the compressor body and generates regenerative electric power. Electric machine,
An inverter that changes the frequency of the supplied power to control the rotational speed of the rotating electrical machine;
A converter that generates an output power from the generated power;
A check valve for permitting the flow of compressed air from the compressor body side to the discharge side on the discharge side piping of the compressor body;
An external intake pipe communicating with a discharge piping path from the discharge side of the compressor body to the upstream of the check valve and taking in compressed air from one or more other gas compressors B,
The compressor main body is reversely rotated by the compressor air taken in from the external intake pipe at the time of operation standby of the compressor main body, thereby generating power for generating the regenerative power.
The gas compressor B is
An electric motor for driving the compressor body, and a check valve for permitting the flow of compressed air from the compressor body side to the discharge side on the discharge side pipe of the compressor body;
It has an air release pipe for discharging compressed air upstream of the check valve, and an air release valve installed on the air release pipe,
The gas compressor system is
A downstream side from an air release valve of the gas compressor B communicates with an external intake pipe of the gas compressor A,
A gas compressor which is communicably connected to the plurality of gas compressors, and includes a control device for opening the air release valve when the gas compression A is on standby and when the gas compressor B discharges air. system.

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