JP5379723B2 - Fluid machine, fluid machine operation control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid machine having fluid machine strength prevented from being damaged even during excess rotation by a simple structure when an excessive fluid flow is entered into a fluid flow passage from the outside, and further immediately returned to normal rotational speed when a forcible excessive rotational phenomenon has passed. <P>SOLUTION: This fluid machine is provided in the fluid flow passage (air duct 11), and delivers fluid from one direction of the fluid flow passage to the other direction thereof by rotating a rotary vane 15 by a driving machine (electric motor 17). A first mechanical one-way clutch 16 transmitting torque of the driving machine only in a normal rotational direction to the rotating shaft of the rotary vane is arranged between the rotating shaft of the rotary vane 15 and the driving shaft of the driving machine, and a second mechanical one-way clutch 26 allowing rotation of the driving shaft in the normal rotational direction and preventing rotation in an inverse direction is arranged between the driving shaft of the driving machine and a stationary side. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an operation control device for a fluid machine that is disposed in a flow path such as an exhaust duct and sends an air flow from one end of the flow path to the other end, and in particular, an air flow (wind) having a pressure from the outside from one end. The present invention relates to a fluid machine such as a ventilation fan and a fluid machine operation control device arranged in a flow path entering the other end (forward flow direction) and from the other end to one end (reverse flow direction).

  Conventionally, as an example of a fluid machine such as an exhaust duct that is disposed in a fluid flow channel 100 as shown in FIG. 1A and sends fluid from one end of the fluid flow channel 100 to the other end, There is a ventilation fan 101 located in the fluid flow path. The ventilation fan 101 includes a rotor blade 102. By rotating and driving the rotor blade 102 with an electric motor 103, an air flow sucked from one end of the fluid flow path 100 is sent to the other end as indicated by an arrow B and discharged. doing.

  In the ventilation fan 101 as described above, an air flow having a pressure that cannot maintain the normal rotation of the ventilation fan 101 in the fluid flow path 100 flows back as shown by arrows C and D in FIGS. There is a case to enter the direction and the positive flow direction. As a countermeasure in such a case, conventionally, as shown in FIG. 2, a damper 107 is arranged before or after the ventilation fan 101, and the damper 107 is fully closed to prevent direct airflow from reaching the ventilation fan 101. doing.

  Even if the damper 107 is closed and the fluid flow path 100 is shut off as described above, when the operation of the ventilation fan 101 is continued, the operation point of the ventilation fan 101 is a deadline operation with zero air volume. In this case, in the “air volume-shaft power operation characteristics” of the ventilation fan, when the shaft power exceeds or falls below the rated shaft power of the electric motor 103, the following two correspondences (1) and (2) are satisfied. Divided.

(1) When the closing shaft power of the ventilation fan 101 exceeds the rated shaft power of the electric motor 103 When the closing shaft power of the ventilation fan 101 exceeds the rated shaft power of the electric motor 103, the electric motor 103 is overloaded. Therefore, continuous operation is not possible. In order to continue operation without stopping the operation of the ventilation fan 101, the following measures are required.
-As shown in FIG. 3, the bypass flow path 106 provided with the damper 108 is installed. When the damper 107 is closed and the fluid flow path 100 is shut off, the damper 108 is opened to switch the air flow path to circulate air and avoid the shutoff operation of the ventilation fan 101.
When the blade type of the rotor blade 102 of the ventilation fan 101 is a fixed blade, as shown in FIG. Reduce to an acceptable range.
When the blade type of the rotary blade 102 of the ventilation fan 101 is a movable blade type, the shaft power is forcibly reduced to an allowable range by reducing the air volume and the total pressure by changing the blade angle as shown in FIG.

(2) When the closing shaft power of the ventilation fan is lower than the rated shaft power of the electric motor When the closing shaft power of the ventilation fan 101 is lower than the rated shaft power of the electric motor 103, the electric motor 103 is not overloaded. Continuous operation is not restricted. However, because the deadline operation is a state in which the airflow is greatly disturbed and forcedly circulated inside the ventilation fan 101, the fluid force is unbalanced, and the bearings and the like are deteriorated due to adverse effects such as increased vibration. It is not preferable. Therefore, it is necessary to take measures such as setting a time limit.

The above conventional measures have the following problems.
-Since it is necessary to close the damper 107 every time an airflow enters the fluid flow path 100 from the outside, the entry of the airflow from the outside and the decrease in the influence of the airflow are detected in a controlled manner, and a time margin is secured. It is necessary to control the opening and closing of the damper 107.
-When the damper 107 is closed, the fluid flow path 100 is completely cut off, and the ventilation function is completely stopped.
-If the damper 107 is operated incorrectly or fails, the fluid flow path 100 cannot be blocked. In this case, the ventilation fan 101 is damaged depending on the degree. The following problems occur from the direction of airflow.

(A) When excessive airflow enters in the reverse flow direction of the ventilation fan 101 As shown in FIG. 6, the ventilation fan 101 normally rotates in the direction indicated by the arrow A and sends the airflow in the forward flow direction indicated by the arrow B. At time t1, the pressure applied to the fan, the fan air volume (m ³ / min), the fan speed (min ⁻¹ ), and the fan current value (A) are in a normal state. The fan air volume decreases due to the characteristics of the ventilation fan 101 as time t <b> 2 and time t <b> 3 at which the intensity of the pressure air that reaches the fan (pressure air that extends in the reverse flow direction of the ventilation fan 101) increases. At the same time, the fan shaft power necessary for the ventilation fan 101 acts in the direction of increasing, and the fan current value (A) also acts in the direction of increasing as the fan shaft power increases. When the fan current value (A) reaches the overcurrent value at time t4, the protection device operates in the power supply path, the switch is opened, the fan driving force for driving the ventilation fan 101 is lost, and the ventilation fan 101 is unconstrained. Then, the pressure winds across the fan reverses in the direction of arrow E, and reaches the runaway rotational speed (saturated rotational speed at which the ventilation fan 101 is rotated by the airflow).

  When the reverse rotation speed of the ventilation fan 101 becomes excessive and the runaway rotation speed is reached, excessive centrifugal force is generated in the rotating portion, causing damage beyond the allowable strength of the rotating blade 102 and the mounting portion of the rotating blade 102. May cause damage to the bearing, damage to the rotating body due to excessive vibration when the rotational speed of the main shaft matches the natural frequency.

(B) When excessive airflow enters in the positive flow direction of the ventilation fan As shown in FIG. 7, the ventilation fan 101 normally rotates in the direction indicated by the arrow A and sends the airflow in the positive flow direction indicated by the arrow B. At time t1, the pressure applied to the fan, the fan air volume (m ³ / min), the fan speed (min ⁻¹ ), and the fan current value (A) are in a normal state. The pressure applied to the fan (pressure applied in the positive flow direction of the ventilation fan 101) increases in wind strength, and the fan air volume is characteristic in time t2 and time t3 when the pressure of the wind generated by the ventilation fan 101 itself decreases. Increase. At the same time, the fan shaft power required for the ventilation fan 101 itself acts in a direction to be reduced, and the fan current value (A) also acts in a direction to decrease as the fan shaft power decreases. At time t4, the fan current value reaches the lowest limit value. Furthermore, when the pressure wind that reaches the fan becomes stronger, the direction of the current shifts from power running to the power generation region / regeneration, but as a normal facility, a protection control circuit is formed before the regeneration, and the switch in the power supply path is opened. As a result, the driving force of the ventilation fan 101 is lost, the ventilation fan 101 becomes unconstrained, the rotation is accelerated by the forward flow direction and the pressure wind, and the runaway rotation speed (saturation rotation speed at which the ventilation fan 101 is rotated by the air flow). To reach.

  When the rotational speed of the ventilation fan 101 becomes excessive, an excessive centrifugal force is generated in the rotating part, which may cause damage beyond the allowable strength of the rotating blade 102 or the mounting part of the rotating blade 102, Or the rotational speed of the main shaft matches the natural frequency, leading to damage of the rotating body due to excessive vibration.

  In addition, even if the excessive air flow entering is in the reverse flow direction or in the forward flow direction, if the electric circuit switch is opened, the excessive air flow will stop and the ventilation fan 101 can be operated by the speed control device. Even in such a case, the electric circuit switch must be closed to reset the speed control device, which may hinder rapid restart of operation. Furthermore, when an excessive air flow occurs repeatedly, the circuit switch is repeatedly opened and closed, reducing the life of the circuit switch. In addition, in order to avoid a problem when the damper 107 is erroneously operated or fails, it is necessary to take measures such as providing a backup facility for the damper (duplexing of the damper, etc.).

JP-A-63-138197 Japanese Patent Laid-Open No. 4-175500

  The present invention has been made in view of the above-described points. When an excessive fluid flow enters the fluid flow path in which the fluid machine is disposed inside from the outside in the reverse flow direction and the forward flow direction, It has a simple configuration that does not require blocking the flow path or backing up the damper function. It has fluid machine strength that will not be damaged even when the maximum fluid machine rotating part over-rotates. It is an object of the present invention to provide a fluid machine capable of quickly returning to a normal rotational speed and sending a fluid when settled.

  In addition, the present invention reduces the flow efficiency by shutting off the flow path when excessive pressure fluid enters from the outside in the reverse flow direction and forward flow direction inside the flow path where a fluid machine such as a ventilation fan is arranged. And avoiding the occurrence of electrical failures such as overload due to the regeneration of electric power (electric current) from the fluid motor's electric motor that uses this pressure fluid as the source, and the increase in the required power value. A fluid machine that automatically (mechanically) suppresses the pressure wind when the fluid flow that causes the above over-rotation (reverse rotation) enters, and that the rotating blade does not reach the dangerous reverse rotation speed even at the maximum counter-wind pressure. It is an object of the present invention to provide a fluid machine operation control device capable of quickly returning a fluid machine to a normal rotation speed and sending a fluid flow when the pressure fluid causing a forced over-rotation phenomenon has left and settled. .

  In order to solve the above-mentioned problems, the present invention is a fluid machine that is arranged in a fluid flow path and sends a fluid from one direction of the fluid flow path to the other by rotating the rotary blade with a driving machine. A first mechanical one-way clutch is disposed between the rotary shaft and the drive shaft of the drive machine so as to transmit the rotational force only in the forward rotation direction of the drive machine to the rotary shaft of the rotor blade. A second mechanical one-way clutch that allows rotation in the forward rotation direction of the drive shaft and prevents rotation in the reverse rotation direction is disposed therebetween.

  Further, in the fluid machine described above, the flow of the fluid flowing in the fluid flow path by the rotation of the rotor blades by the forward rotation of the driving machine is the forward flow direction, the opposite flow is the reverse flow direction, When the fluid in the reverse flow direction enters from and the reverse rotation of the rotor blades and the drive machine due to the pressure is prevented by the second mechanical one-way clutch, the pressure of the fluid weakens and the rotor blades can rotate forward. The first control means for rotating the rotor blades by the driving machine, and the fluid in the positive flow direction enters the fluid flow path from the outside, and the rotor blades rotate at a faster rotational speed than the driving machine by the pressure, When the rotor blade, which has been released from the coupling between the rotor shaft and the drive shaft of the drive machine by one mechanical one-way clutch, rotates independently, the drive machine is maintained at a predetermined rotational speed, and the fluid pressure decreases. When the rotational speed decreases and returns to the specified rotational speed A second control means for the rotation of the rotary blade by the driving device, characterized in that the provided.

  Further, the present invention provides a fluid machine operation control device that controls the operation of a fluid machine that is disposed in a flow path and that rotates a rotor blade with a driving machine to send a fluid flow from one of the flow paths to the other. The control device includes a control device, a driving operation control device, and a protection control device. The speed control device normally outputs power for rotating the rotor blades at a set rotational speed commanded from the driving operation control device to the driving machine. Function and a free-run control function for free rotation of the rotating body including the rotor blades of the fluid machine by eliminating the power output to the drive machine, and the operation control device is set to the speed control device during normal control. It has a normal control instruction function that sends a signal and rotates the rotor blades at the set number of revolutions, and the protection control device free-runs the rotating body in the speed control device when an external pressure fluid flow outside the allowable range enters the flow path. Nisa That includes a free-running instruction function, characterized by using a fluid machine of the above described fluid machine.

  Further, according to the present invention, in the fluid machine operation control device, the protection control device notifies the operation control device that the protection control has started when the speed control device instructs the free run; A protection control end notification function is provided to notify the end of protection control when the external pressure fluid acting on the passage falls within the allowable range.

  According to the present invention, when a fluid flow having pressure enters the fluid flow path in which the fluid machine is disposed from the outside and reaches the fluid machine in both the normal flow direction and the reverse flow direction, the pressure of the fluid flow is reduced. Even when the normal rotation speed of the rotor blades and the drive machine cannot be maintained, the rotor blades are allowed to rotate forcibly without shutting off the fluid flow path of dampers or electrically opening the electric switch When the influence of the fluid flow is reduced, it is possible to construct a fluid machine that can quickly return the rotor blades to normal operation at a predetermined normal rotation speed, simplifying equipment, simplifying operation and control. It becomes a rational facility when it becomes possible.

  Further, according to the present invention, the speed control device normally outputs the power for rotating the rotor blades at the set rotational speed commanded from the operation control device to the drive machine, and the power output to the drive machine. Equipped with a free-run control function that allows the rotating body including the rotor blades of the lost fluid machine to rotate freely, and the operation control device sends a set rotation speed signal to the speed control device during normal control to rotate the rotor blades at the set rotation speed. A normal control instruction function is provided, and the protection control device has a free run instruction function that causes the speed control device to put the rotating body in a free run state when an external pressure fluid flow outside the allowable range enters the flow path. When excessive pressure fluid enters from the outside in the reverse flow direction and forward flow direction inside the passage, the flow of the fluid machine is reduced without blocking the flow path and reducing the fluid flow efficiency. Target To avoid the occurrence of a failure, further away an external pressure fluid flow, can provide a fluid machine operation control system which quickly fluid machine with calm time can send a fluid flow is returned to the speed of normal.

FIG. 1 is a diagram showing a schematic configuration example of a conventional ventilation fan. FIG. 2 is a diagram illustrating a schematic configuration example of a conventional ventilation fan. FIG. 3 is a diagram showing a case where a bypass air passage is installed in the fluid passage. FIG. 4 is a diagram for explaining a method of reducing the deadline shaft power when the blade type of the ventilation fan is a fixed blade. FIG. 5 is a diagram for explaining a method of reducing the deadline shaft power when the blade type of the ventilation fan is a movable blade. FIG. 6 is a view for explaining a case where an airflow in the reverse flow direction enters from the outside into an air passage in which a conventional ventilation fan is arranged. FIG. 7 is a view for explaining a case where an air flow in the positive flow direction enters from the outside into an air passage in which a conventional ventilation fan is arranged. FIG. 8 is a diagram showing a system configuration example of the ventilation fan operation control device according to the present invention. FIG. 9 is a diagram showing a control flow of the ventilation fan operation control device of FIG. FIG. 10 is a diagram for explaining a free-run transition standard of the ventilation fan operation control device. FIG. 11 is a diagram showing a system configuration example of the ventilation fan operation control device according to the present invention. FIG. 12 is a diagram showing a control flow of the ventilation fan operation control device of FIG. FIG. 13 is a diagram showing a cross-sectional configuration example of a ventilation fan which is an example of the fluid machine of the present invention. FIG. 14 is a view for explaining a case where an airflow in the reverse direction enters from the outside into the air passage in which the ventilation fan according to the present invention is arranged. FIG. 15 is a view for explaining a case where an airflow in the positive flow direction enters from the outside into an air passage in which a ventilation fan according to the present invention is arranged.

  Hereinafter, embodiments of the present invention will be described in detail. FIG. 8 is a diagram showing a system configuration of a ventilation fan operation control device as a fluid machine operation control device according to the present invention. In this embodiment, a ventilation fan is described as an example of a fluid machine. However, the present invention can be applied to a fluid machine operation control device that is disposed in a flow path and sends a fluid from one end to the other end of the flow path. As shown in FIG. 8, the fluid machine operation control device performs operation control of the ventilation fan operation control device 1, the ventilation fan protection control device 2, the speed control device 3, and the ventilation fan 10 arranged in the air passage 11. It is like that. Here, the ventilation fan 10 is a ventilation fan having a general fixed wing. The ventilation fan operation control device 1 is a device that performs normal operation control of the ventilation fan 10, and the ventilation fan protection control device 2 is a device that protects the ventilation fan 10 and the like. The ventilation fan protection control device 2 is the same type of control device, but is divided here for easy understanding of the function.

  The ventilation fan operation control device 1 transmits a control target detection signal such as the temperature in the air passage 11 from the control target signal transmitter 31, a driving / stop command signal from the driving / stop command signal transmitter 32, and a set rotational speed transmission. Receiving the set rotational speed signal from the device (distant operation unit) 33 and the measured rotational speed signal of the ventilation fan 10 from the rotational speed transmitter 27, generating the set rotational speed signal of the ventilation fan 10, and setting the rotational speed transmitter The set rotational speed signal is transmitted from 1a to the speed control device 3.

  The ventilation fan protection control device 2 includes a free-run command signal transmitter 2a, a restart command (acceleration) signal transmitter 2b, a protection control start signal transmitter 2c, and a protection control end signal transmitter 2d, and transmits an external force state quantity. A state quantity detection signal of an external force such as pressure or air volume from the air conditioner 37, an actual speed signal of the ventilation fan 10 from the speed transmitter 27, an output speed signal from the inverter control section 36, and an inverter output section 35 An electric power (current) signal output to the electric motor 17 is received.

  Further, the ventilation fan protection control device 2 is in a situation where electric failure such as regeneration of electric power (current) of the electric motor 17 of the ventilation fan 10 or overload can occur, and the electric motor 17 and the speed control device. 3, when it is necessary to protect equipment such as an electric circuit, a free-run command signal is output from the free-run command signal transmitter 2 a to the speed control device 3 to control the equipment from an electrical failure. Further, the ventilation fan protection control device 2 performs control to maintain a state where the circuit breaker upstream of the power wiring that supplies power to the speed control device 3 is not opened.

  Further, the ventilation fan protection control device 2 informs the ventilation fan operation control device 1 that the protection control has been started via the protection control start signal transmitter 2c, and interrupts normal control, or an external force state quantity transmitter 37. After confirming that the condition for enabling the free run is completed from the pressure or the external force state quantity detected in step 3, the restart command signal is sent from the restart command signal transmitter 2b to the speed control device 3. The ventilation fan 10 is normally operated by the function of returning the electric motor 17 of the ventilation fan 10 to the operation at the set rotation speed at the time of normal control or the measured rotation speed signal of the ventilation fan 10 detected by the rotation speed transmitter 27. It has a function of detecting that the rotational speed has been returned to the time of control and outputting a protection control end signal to the ventilation fan operation control device 1 via the protection control end signal transmitter 2d.

  The speed control device 3 includes an inverter output unit 35, receives the set rotational speed signal of the set rotational speed transmitter 1 a of the ventilation fan operation control device 1, and the inverter control unit 36 converts the rotational speed of the ventilation fan 10 to the set rotational speed. Is generated and output to the inverter output unit 35. The inverter output unit 35 receives the frequency signal and supplies electric power (current) having a frequency that reaches the set rotational speed to the electric motor 17 of the ventilation fan 10. As a result, the rotor blade 15 of the ventilation fan 10 rotates forward (rotates in the direction indicated by arrow A), passes through the casing of the ventilation fan 10, and extends from one end to the other end of the air passage 11 connected to the casing. As shown by arrow B, wind (airflow) is sent.

  Further, the speed control device 3 receives the free run command signal from the free run command signal transmitter 2 a of the ventilation fan protection control device 2 and eliminates the power supplied from the inverter output unit 35 to the electric motor 17 of the ventilation fan 10. A state where the rotating body of the ventilation fan 10 including the rotating portion of the electric motor 17 can be freely rotated, that is, a free-run function for setting the rotating body to a free-run state is provided. The speed control device 3 receives the restart command signal from the restart command signal transmitter 2 b of the ventilation fan protection control device 2 and supplies the output power of the inverter output unit 35 to the electric motor 17 of the ventilation fan 10.

  FIG. 9 is a diagram showing a control flow of the ventilation fan operation control device. First, in step ST11, the normal control of the ventilation fan 10, that is, the speed control device 3 has a frequency power (the frequency at which the rotation speed of the ventilation fan 10 becomes the set rotation number from the set rotation number transmitter 1a of the ventilation fan operation control device 1). Current) is supplied from the inverter output unit 35 to the electric motor 17 of the ventilation fan 10. In step ST12, the actual rotational speed of the ventilation fan 10 from the rotational speed transmitter 27 is set to N, and as shown in FIG. 10 (a) and FIG. The (current) value range is calculated to obtain a low power (current) side specified value AL and a high power (current) side specified value AH.

  In step ST13, the electric power value (current value) supplied from the inverter output unit 35 to the electric motor 17 is A, and “free run” transition reference processing, that is, detection of the regenerative current itself, or current to avoid regenerative. The detection of the value condition A <AL, and the detection of the current value condition A> AH that should avoid overload (overcurrent) are checked. If either one is satisfied (OR), the process proceeds to step ST14. In step ST14, protection control of the ventilation fan 10 is started, and the process proceeds to step ST15. At the same time, the normal control of the ventilation fan 10 is interrupted.

  In step ST15, a free-run command signal is transmitted from the free-run command signal transmitter 2a of the ventilation fan protection control device 2 to the speed control device 3, and the process proceeds to step ST16. At step ST16, the external force state quantity transmitter 37 detects the external force state quantity (pressure or air volume) B with a prescribed value, and waits for the external force state quantity B to return to the prescribed value. When returning to the inside, that is, as shown in FIG. 10C, when the external force state quantity B falls within the range between the low pressure side external force reference value (−) BL and the high pressure side external force reference value (+) BH, the process proceeds to step ST17. To do.

  In step ST17, the rotation direction of the ventilation fan 10 is detected, and the flow is branched depending on the rotation direction. If the rotation direction is reverse, the process proceeds to step ST18. In step ST18, after detecting that the rotation speed (reverse rotation) of the ventilation fan 10 has decelerated to within the specified value, the process proceeds to step ST20, the free run is terminated, and then the process proceeds to step ST21. In step ST21, the ventilation fan protection control device 2 outputs a restart command signal from the restart command signal transmitter 2b to the speed control device 3 to restart the ventilation fan 10, and the process proceeds to step ST23. If the rotation direction of the ventilation fan 10 is normal in step ST17, the process proceeds to step ST19, the free run is terminated, and then the process proceeds to step ST22. In step ST22, even if the ventilation fan 10 is rotating, it is restarted from the rotational speed, and the process proceeds to step ST23. In step ST23, the ventilation fan 10 is accelerated, and the process proceeds to step ST24. In step ST24, control is performed to set the rotational speed of the ventilation fan 10 to the set rotational speed, and the control returns to normal control, and the process proceeds to step ST25 to end the ventilation fan protection control.

  Some speed control devices 3 are provided with a power regeneration function. In this case, the free run movement reference value on the regeneration side (rotating body side) is set to a regenerative capacity, and the forward rotation side excess It is also possible to collect power (electric power) as much as possible during rotation. In this case, in step ST13, detection of the regenerative current is excluded from the reference, and AL is set as a negative current value (current value that can be regenerated).

  In addition, when the number of rotations that can be restarted at the time when the free run ends is limited on the low rotation number side, the regenerative braking is performed in order to quickly stop the rotor blades 15 of the ventilation fan 10 that is freely rotating. Thus, the rotation of the rotating body composed of the rotating portions of the rotary blade 15 and the electric motor 17 can be stopped.

  In addition, in this case, if the state of fluctuation of the state quantity of pressure or air volume is so great that it fluctuates greatly in and out of the specified value range, it may fall into a hunting phenomenon in which the transition of protection control and its termination are repeated. As a means for avoiding the hunting phenomenon, it is possible to add a measure such as setting a holding time from the free run command to the confirmation of the external force state quantity for returning to the normal control.

  FIG. 11 is a diagram showing a system configuration example of the ventilation fan operation control device according to the present invention. The ventilation fan operation control device shown in FIG. 11 is different from the ventilation fan operation control device shown in FIG. 8 in that a free-run braking command signal is transmitted to the ventilation fan protection control device 2 in the ventilation fan operation control device shown in FIG. When the rotational speed of the rotating body of the ventilation fan 10 due to free run returns to within the specified range, a free run braking command signal is transmitted to the speed control device 3 as the end of the free run. Others are the same as the ventilation fan operation control apparatus of FIG.

  FIG. 12 is a diagram showing a control flow of the ventilation fan operation control device shown in FIG. First, in step ST31, normal control of the ventilation fan 10 is performed. In step ST32, the measured rotational speed from the rotational speed transmitter 27 is set to N, and the low power side defined value AL and the high power side defined value AH within the allowable power (current) value range for the measured rotational speed N are calculated and obtained. (See FIGS. 10A and 10B), the process proceeds to step ST33. In step ST33, the electric power value (current value) supplied from the inverter output unit 35 to the electric motor 17 is A, and the “free-run” transition reference process, that is, the detection of the regenerative current itself, or the current that should be avoided. The detection of the value condition A <AL and the detection of the current value condition A> AH that should avoid overload (overcurrent) are checked. If either one is satisfied (OR), the process proceeds to step ST34. In step ST34, protection control of the ventilation fan 10 is started, and the process proceeds to step ST35. At the same time, the normal control of the ventilation fan 10 is interrupted.

  In step ST35, a free-run command signal is transmitted from the free-run command signal transmitter 2a of the ventilation fan protection control device 2 to the speed control device 3, and the process proceeds to step ST36. In step ST36, in order to prevent the hunting phenomenon in which the transition of the protection control and the end thereof are repeated, a predetermined free run holding time is set by a timer or the like, and the process moves to step ST37 after the free run holding time has elapsed. In step ST37, the external force state quantity B detected by the external force state quantity transmitter 37 is compared with a specified value, and is returned to the specified value, that is, the external force state quantity B is equal to the low-pressure side external force reference value (-) BL. It is determined whether or not the pressure has returned during the high-pressure side external force reference value (+) BH (see FIG. 10C), and if it returns within the specified value, the process proceeds to step ST38.

    In step ST38, the free run ends and the process proceeds to step ST39. In step ST39, the rotation direction of the ventilation fan 10 is detected, and the flow is branched depending on the rotation direction. If the rotation direction is reverse, the process proceeds to step ST40. In step ST40, a free-run braking command signal transmitter 2e of the ventilation fan protection control device 2 transmits a free-run braking command signal to the speed control device 3, and the rotational speed braking (deceleration operation) of the ventilation fan 10 that is rotating in inertia is performed. ) And move to step ST42. In step ST42, after detecting that the rotation speed of the ventilation fan 10 has decelerated to within a specified value, the process proceeds to step ST43. In step ST43, the restart command signal transmitter 2b of the ventilation fan protection control device 2 outputs a restart command signal to the speed control device 3 to restart the ventilation fan 10, and the process proceeds to step ST44. If the rotation direction of the ventilation fan 10 is normal in step ST39, the process proceeds to step ST41. In step ST41, even if the ventilation fan 10 is rotating, it is restarted from the rotational speed, and the process proceeds to step ST44.

  In step ST44, the ventilation fan 10 is accelerated, and the process proceeds to step ST45. In step ST45, control is performed to set the rotational speed of the ventilation fan 10 to the set rotational speed, and the control returns to normal control, and the process proceeds to step ST46 to end the ventilation fan protection control.

  FIG. 13 is a diagram showing a cross-sectional configuration example of a fluid machine according to the present invention. In this embodiment, a ventilation fan is described as an example of a fluid machine. However, the present invention can be applied to a fluid machine that is disposed in a fluid flow path and sends a fluid from one end of the fluid flow path to the other end. In FIG. 13, the ventilation fan 10 is arrange | positioned in the air path 11 as a fluid flow path. That is, the inner casing 13 of the ventilation fan 10 is arranged and fixed at a predetermined position in the ventilation fan 10 via the fixing member 12. As indicated by an arrow A by rotating the ventilation fan 10 forward, an air flow sucked from one end (not shown) of the air passage 11 is indicated by an arrow B from the discharge port 14 which is the other end of the air passage 11. Discharged.

  Reference numeral 15 denotes a rotor blade of the ventilation fan 10, and the rotor blade 15 is connected to one end of a motor rotating shaft 18 of an electric motor 17 as a driving machine via a first mechanical one-way clutch 16. As a result, the rotary blade 15 rotates by receiving the rotational force of the motor rotary shaft 18 of the electric motor 17 only in the normal rotation direction (normal rotation) during the normal operation. When the rotating blade 15 of the ventilation fan 10 receives an airflow from the outside in the same direction as the arrows A and B (airflow in the positive flow direction) and rotates at a speed faster than the rotational speed of the electric motor 17, It is separated from the motor rotating shaft 18 and rotates independently. Reference numeral 19 denotes a rotor blade shaft that supports the rotor blades. The rotor blade shaft 19 is rotatably supported with respect to the inner casing 13 via a bearing 20. A rotational speed detector (TG) 22 for detecting the rotational speed of the rotary blade 15 is connected to one end of the rotary blade shaft 19.

  The electric motor 17 includes a stator 17a and a rotor 17b. The stator 17a is fixed to the motor casing 23, and the rotor 17b is fixed to the motor rotating shaft 18 so as to pass through the stator 17a and be freely rotatable. The motor casing 23 is fixed to the casing of the ventilation fan 10 via the inner casing 13. Both end portions of the motor rotating shaft 18 are rotatably supported with respect to the inner casing 13 via bearings 25 and 25. The other end of the motor rotating shaft 18 of the electric motor 17 is connected to the fixed side via a second mechanical one-way clutch 26. That is, the reverse rotation of the electric motor 17 is forcibly prevented by the second mechanical one-way clutch 26. A rotation speed detector (TG) 27 for detecting the rotation speed is connected to the other end of the motor rotation shaft 18 of the electric motor 17.

  In the ventilation fan 10 configured as described above, for example, a saddle type induction electric motor is used as the electric motor 17, and the frequency of electric power supplied to the stator 17a is controlled by inverter control (not shown) to control the number of rotations. . When an air flow in the direction opposite to arrows A and B (reverse flow direction) enters the air passage 11 from the outside, the pressure becomes stronger, and the air flow of the ventilation fan 10 changes from zero to the reverse air flow, the rotating blade 15 rotates in the reverse direction. In response to the force, the motor rotating shaft 18 of the electric motor 17 tries to rotate in the reverse direction, but this is forcibly blocked by the second mechanical one-way clutch 26.

  While the rotary blade 15 receives the reverse rotational force and the electric motor 17 is forcibly blocked by the second mechanical one-way clutch 26, the electric motor is controlled by the first control means such as inverter control. The electric power supply to the electric motor 17 is stopped, and the stator 17a of the electric motor 17 and the motor rotating shaft 18 are unconstrained (free run) control (the second mechanical one-way clutch 26 restricts the rotation of the electric motor 17 to zero. Control to prevent electrical failure). Then, when the wind pressure of the airflow in the reverse direction decreases and the pressure in the air passage 11 becomes equal to or less than a predetermined value, the power supply from the inverter to the electric motor 17 is resumed so that the ventilation fan 10 reaches the rated rotational speed. Re-accelerate and control.

  When the airflow in the positive flow direction in the same direction as arrows A and B enters the air passage 11 from the outside, the pressure becomes stronger, and the rotor blade 15 of the ventilation fan 10 rotates at a speed higher than the rotational speed of the electric motor 17. The connection between the rotary blade shaft 19 of the rotary blade 15 and the motor rotary shaft 18 of the electric motor 17 is released by the one mechanical one-way clutch 16, and the rotary blade 15 is independently driven by the pressure of the airflow in the forward flow direction. Rotates faster than 18. The rotational speed of the rotary blade 15 is monitored by the output of the rotational speed detector (TG) 22, and while the rotary blade 15 is independently rotating at a high speed with the air flow in the positive direction, the second control means controls the motor. The motor 17 is controlled so as to maintain the designated rotational speed. The wind pressure of the airflow in the positive flow direction decreases, the rotational speed of the rotary blade 15 returns to the specified rotational speed, and the rotary blade shaft 19 of the rotary blade 15 and the motor rotary shaft 18 of the electric motor 17 are reconnected.

  In the ventilation fan 10 having the above-described configuration, the motor rotating shaft 18 of the electric motor 17 needs to have rigidity capable of withstanding a transient maximum torsional force when an excessive reverse air flow enters the air passage 11. . The strength of the first mechanical one-way clutch 16 is set so that it can withstand even when the rotor blade 15 rotates at the runaway rotational speed. Further, the bearing 20 that supports the rotor blade shaft 19 of the rotor blade 15 withstands the thrust force when the rotor blade 15 receives the airflow in the reverse direction and the forward airflow of the maximum wind pressure, and withstands the rotational speed at that time. It is necessary to set the strength as high as possible.

As described above, when an airflow in the opposite direction or the forward direction to the airflow sent from the outside by the ventilation fan 10 enters the air passage 11, a reverse rotational force or a positive rotational force is applied to the rotary blades 15 of the ventilation fan 10. 14 and 15 show the pressure (Pa), fan air volume (m ³ / min), fan rotation speed (min ⁻¹ ), fan shaft power (kw) applied to the fan when airflow enters the air passage 11 from the outside. ), Fan torque (kg · m), and fan current value. FIG. 14 shows a case where an airflow in the backward flow direction enters the air passage 11, and FIG. 15 shows a case where an airflow in the forward flow direction enters.

  FIG. 14 shows a state in which the rotor blade 15 of the ventilation fan 10 rotates forward as indicated by an arrow C, and air current is discharged from the outlet 14 of the air path 11 as indicated by an arrow B from the outside. As shown by the arrow D, the case where the airflow in the reverse flow direction enters is shown. As shown in FIG. 14A, the pressure (Pa) of the reverse airflow exerted on the ventilation fan 10 (rotary blade 15) increases in the positive pressure direction with time t1, t2, t3, and t4. However, it becomes the highest at time t5, and descends in the negative pressure direction with the passage of time t6, t7, t8, t9.

Since the ventilation fan 10 is rated, the fan air volume of the ventilation fan 10 (air volume in the air passage 11) (m ³ / min) and the fan speed (min ⁻¹ ) is + 100% as shown in FIGS. 14B and 14C. Further, the fan shaft power (kw) and the fan torque (kg · m) of the ventilation fan 10 are both rated values as shown in FIGS. 14 (d) and 14 (e). Furthermore, the fan current value is a rated current value as shown in FIG.

  As the wind pressure of the reverse air flow increases at times t2 and t3, the fan air volume decreases and the fan current value (current value of the electric motor 17) becomes a constant value at point P7 at time t3 when the fan current value exceeds the specified current value. Reduce the rotation speed by controlling the fan rotation speed so that it does not exceed. When the reverse wind pressure becomes significant, the rotational speed becomes zero at the point P2 at time t4. When the current value exceeds the upper limit value, the power supply from the inverter to the electric motor 17 is stopped thereafter, and the stator 17a of the electric motor 17 and the motor rotating shaft are stopped. The control shifts to free-run control in which 18 is unconstrained (free), and the rotation to the reverse side is restrained by the second mechanical one-way clutch 26. At time t6 when the pressure in the air passage 11 becomes equal to or less than a predetermined value, the rotation speed output by the inverter is resumed and the rotation speed is reaccelerated. Between point P3 and point P4 at time t7, when the rotational speed is increased by rotational speed control that adjusts the rotational speed so as not to exceed the specified current value by the current value, and when the rotational speed at point P4 reaches 100% Then, the rotational speed control by the current value is finished.

  As shown in FIG. 14 (d), the fan shaft power increases with the increase of the wind pressure and the fan air volume in the backward flow direction to the point P5 after the time t1 to the time t4, and at the point P2, the output of the inverter is increased. Shift to free-run control with no Thereby, it controls until the time t6 passes. Thereafter, the operation restarts and reaccelerates as the wind pressure and fan air flow decrease, and the fan shaft power value changes with time as shown at times t7, t8, and t9, and the airflow pressure in the reverse flow direction becomes zero. At time t9, the fan shaft power at the rated time is obtained.

  Further, as shown in FIG. 14 (e), the fan torque increases with the increase of the air pressure and the fan air flow in the reverse direction up to the point P6 after the time t1 to the time t4, and at the point P2, the inverter torque is increased. Shift to free-run control with no output. As a result, the torque is maintained at zero until the time t6 has passed, the operation is restarted and reaccelerated as the wind pressure decreases, and the fan torque value is increased by the rotational speed control based on the current value, as shown at times t7, t8, and t9. It changes with the passage of time, and at the time t9 when the pressure of the airflow in the reverse flow direction becomes zero, the fan torque at the rated time is reached.

  As shown in FIG. 14 (f), the fan current value increases with the increase of the wind pressure and the fan airflow of the reverse airflow from time t1 to time t3, and rotates at the point P7 where the current value becomes the specified current value. The control is continued until the time t6 is over, and the operation is resumed / re-accelerated as the wind pressure and the fan air volume decrease. Then, the speed is increased by the rotational speed control that increases or decreases the rotational speed so as not to exceed the specified current value by the current value, and changes with time as indicated by times t7, t8, t9, and the pressure of the airflow in the reverse flow direction The rated current is reached at time t9 when it becomes zero.

  FIG. 15 shows the air passage 11 from the outside in a state where the rotor blade 15 of the ventilation fan 10 is rotated forward as indicated by an arrow C and an air flow is discharged from the outlet 14 of the air passage 11 as indicated by an arrow B. The case where the airflow of a positive flow direction approached into the inside as shown by the arrow E is shown. As shown in FIG. 15 (a), the wind pressure (Pa) of the airflow in the positive flow direction exerted on the ventilation fan 10 (rotary blade 15) is increased in the negative pressure direction with time t1, t2, t3, t4 and the passage of time. It rises, becomes the highest at time t5, and falls in the positive pressure direction with the passage of time t6, t7, t8, t9.

  Further, as shown in FIG. 15B, the fan air volume increases with the passage of time from 0% of time t1 to time t2, t3, t4, reaches the highest point at time t5, and reaches the highest point at time t5. From time t6, t7, t8, it decreases with the passage of time and reaches 0% at time t9.

Further, as shown in FIG. 15C, the rotation speed of the fan is the motor rotation shaft of the electric motor 17 by the first mechanical one-way clutch 16 at the time t3 when the wind pressure and the fan airflow in the forward flow direction increase. 18 and the rotor blade shaft 19 of the rotor blade 15 are disconnected. As a result, the rotational speed N ₁₅ of the rotor blade 15 separated from the motor rotating shaft 18 of the electric motor 17 becomes the maximum wind pressure with the passage of time t3, t4 and time as shown by the broken line in FIG. It increases until reaching time t5. In addition, the wind pressure and the fan airflow of the airflow in the positive direction decrease from the highest point at time t5 at time t6 and time t7, and at time t7, the first mechanical one-way clutch 16 rotates with the motor rotating shaft 18 of the electric motor 17. The connection of the rotary blade shaft 19 of the blade 15 is started. As a result, the motor rotating shaft 18 of the electric motor 17 and the rotating blade shaft 19 of the rotating blade 15 are coupled, and the rotational speed N ₁₅ is increased with time t5, t6, t7 and the passage of time as shown by the broken line in FIG. Along with this, it decreases to + 100% at time t7.

  Further, as shown in FIG. 15 (d), the fan shaft power decreases from the rated time at time t1 to times t2 and t3, and at time t3, the motor rotating shaft of the electric motor 17 is driven by the first mechanical one-way clutch 16. When the connection between the blade 18 and the rotor blade 19 of the rotor blade 15 is released, the shaft power value necessary for the no-load operation of the electric motor 17 is obtained, and is maintained at a predetermined fan shaft power value that is a predetermined amount smaller than the rated value. This state continues until the motor rotating shaft 18 of the electric motor 17 and the rotating blade shaft 19 of the rotating blade 15 are connected by the first mechanical one-way clutch 16 at time t7. When the motor rotating shaft 18 of the electric motor 17 and the rotating blade shaft 19 of the rotating blade 15 are connected at time t7, the time increases at time t8, t9 and time, and the fan shaft power at the rated time at time t9. It becomes.

  Further, as shown in FIG. 15 (e), the fan torque decreases from the rated time at time t1 to times t2 and t3, and at time t3, the motor rotating shaft 18 of the electric motor 17 is driven by the first mechanical one-way clutch 16. When the connection between the rotor blade 15 and the rotor blade shaft 19 is released, the torque required for no-load operation of the electric motor 17 is maintained at a predetermined torque value that is a predetermined amount smaller than that at the time of rating. This state continues until the motor rotating shaft 18 of the electric motor 17 and the rotating blade shaft 19 of the rotating blade 15 are connected by the first mechanical one-way clutch 16 at time t7. When the motor rotating shaft 18 of the electric motor 17 and the rotating blade shaft 19 of the rotating blade 15 are connected at time t7, the torque increases with the passage of time t8, t9 and reaches the rated torque at time t9.

  Further, as shown in FIG. 15 (f), the fan current value decreases from the rated current value at time t1 to times t2 and t3, and the motor rotation of the electric motor 17 by the first mechanical one-way clutch 16 at time t3. When the connection between the shaft 18 and the rotor blade shaft 19 of the rotor blade 15 is released, the current value required for the no-load operation of the electric motor 17 is maintained, and is maintained at a predetermined current value that is a predetermined amount smaller than the rated current value. This state continues until the motor rotating shaft 18 of the electric motor 17 and the rotating blade shaft 19 of the rotating blade 15 are connected by the first mechanical one-way clutch 16 at time t7. When the motor rotating shaft 18 of the electric motor 17 and the rotating blade shaft 19 of the rotating blade 15 are coupled at the time t7, the time increases at the times t8 and t9 and the rated current value is reached at the time t9.

  In the above embodiment, the ventilation fan 10 having the configuration shown in FIG. Then, the airflow in the reverse flow direction enters the air passage 11 from the outside, and the second mechanical one-way clutch 26 prevents the rotating blades 15 and the electric motor 17 from rotating in reverse due to the pressure. When the blade 15 is allowed to rotate forward, first control means is provided for rotating the rotor blade by an electric motor. Further, the fluid in the positive flow direction enters from the outside into the air passage 11, and the rotary blade 15 is rotated at a high rotational speed by the electric motor 17 due to the pressure, and the rotary blade 15 is rotated by the first mechanical one-way clutch 16. When the rotor blade 15 whose connection between the shaft 19 and the rotating shaft of the electric motor 17 is independently rotated, the electric motor is maintained and operated at a predetermined rotational speed, the pressure of the airflow is weakened, the rotational speed is decreased, and the predetermined rotational speed is reached. When the number reaches the number, the second control means for rotating the rotary blade 15 by the electric motor 17 is provided.

  Thereby, the airflow in the reverse flow direction or the normal flow direction having pressure enters the air passage 11 from the outside and affects the normal flow direction and the reverse flow direction to the ventilation fan 10, and the pressure of the airflow is the ventilation fan 10. Even if the electric motor 17 is not large enough to maintain the normal rotational speed, the airflow entering the rotor blade 15 without blocking the air passage 11 by a damper or the like or electrically opening the electric motor switch It is possible to construct a ventilation fan system that allows the state to be rotated, and quickly returns to normal operation at a predetermined specified rotational speed again when the influence of the airflow decreases.

  In the above embodiment, the example in which the ventilation fan 10 is disposed in the air passage 11 through which the airflow flows has been described. However, the fluid flow path in which the fluid machine according to the present invention is disposed is limited to the air passage through which the airflow flows. It may be a flow path through which a liquid such as water flows, and the fluid machine may be a pump.

  Moreover, although the electric motor was demonstrated to the example in the said example as a drive machine which rotates a rotary blade, a drive machine is not limited to an electric motor. Moreover, although the vertical induction motor has been described as an example of the electric motor, the electric motor is not limited to this.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Can be modified. Note that any shape or structure not directly described in the specification and drawings is within the technical scope of the present invention as long as the effects of the present invention are achieved.

The present invention relates to a fluid machine such as a fan or a pump installed in a fluid flow path through which a gas or liquid fluid passes, and a fluid flow having a pressure in the reverse flow direction or the forward flow direction in the fluid flow path from the outside. Can be used to affect the fluid flow by the fluid machine installed in the fluid flow path.
In addition, the present invention is installed in a ventilation shaft in which a ventilation fan is installed and ventilates an air passage in which an airflow having a pressure opposite to the blowing direction of the ventilation fan enters, for example, a track tunnel through which a high-speed train passes. In a ventilation fan, etc., every time a train passes, a reverse wind or a normal wind enters the shaft, and a strong normal wind or a reverse wind pressure acts on the ventilation fan. It can be used as a device that protects against rotation and damage.

DESCRIPTION OF SYMBOLS 1 Ventilation fan operation control device 2 Ventilation fan protection control device 3 Speed control device 10 Ventilation fan 11 Air path 15 Rotor blade 16 First mechanical one-way clutch 17 Electric motor 18 Motor rotating shaft 19 Rotor blade shaft 20 Bearing 22 Rotation speed Detector (TG)
23 Motor casing 25 Bearing 26 Second mechanical one-way clutch 27 Speed detector (TG)
31 Control target signal transmitter 32 Operation / stop command signal transmitter 33 Setting speed transmitter 35 Inverter output section 36 Inverter control section 37 External force state quantity transmitter

Claims (4)

A fluid machine that is disposed in a fluid flow path and sends a fluid from one direction of the fluid flow path to the other by rotating a rotor blade with a driving machine,
A first mechanical one-way clutch is disposed between the rotary shaft of the rotary blade and the drive shaft of the drive device, and transmits a rotational force only in the positive rotation direction of the drive device to the rotary shaft of the rotary blade;
2. A fluid machine, wherein a second mechanical one-way clutch is provided between a drive shaft and a stationary side of the drive machine, the second mechanical one-way clutch allowing rotation of the drive shaft in the forward rotation direction and preventing rotation in the reverse rotation direction. The fluid machine according to claim 1,
The flow of the fluid flowing in the fluid flow path by the rotation of the rotor blades by the forward rotation of the drive machine is the forward flow direction, the opposite flow is the reverse flow direction,
The second mechanical one-way clutch prevents the fluid in the reverse flow direction from entering the fluid flow path from the outside and the rotary blade and the drive device from rotating backward due to the pressure, and the pressure of the fluid is weakened. A first control means for rotating the rotor blades by the driver when the rotor blades are allowed to rotate forward;
A fluid in a positive flow direction enters from the outside into the fluid flow path, and the rotary blade rotates at a faster rotational speed than the drive unit due to the pressure, and the rotary shaft of the rotary blade is rotated by the first mechanical one-way clutch. And the driving blade of the driving machine that has been decoupled is rotated independently, the driving machine is maintained at a predetermined rotational speed, the pressure of the fluid is weakened, and the rotational speed is decreased to reduce the predetermined rotational speed. A second control means for rotating the rotor blades by the driver when the rotational speed is reached;
A fluid machine characterized by comprising: In a fluid machine operation control device that performs operation control of a fluid machine that is arranged in a flow path and sends a fluid flow from one of the flow paths to the other by rotating a rotor blade with a driving machine,
A speed control device, a driving operation control device, and a protection control device;
The speed control device normally eliminates the power to be output to the drive machine and the normal control function to output power to the drive machine to rotate the rotor blades at a set rotational speed commanded from the operation control device. A free-run control function for freely rotating a rotating body including the rotor blade of a fluid machine,
The operation control device includes a normal control instruction function that sends the set rotation speed signal to the speed control device during the normal control and rotates the rotor blades at a set rotation speed.
The protection control device includes a free-run instruction function that causes the speed control device to place the rotating body in a free-run state when an external pressure fluid flow outside an allowable range enters the flow path.
A fluid machine operation control apparatus using the fluid machine according to claim 1 or 2 as the fluid machine. In the fluid machine operation control device according to claim 3,
The protection control device includes a protection control start notification function for notifying the driving operation control device that the protection control has started when the speed control device instructs the free run, and an external pressure fluid acting on the flow path. A protection control end notification function for notifying the end of protection control when it falls within the allowable range;
A fluid machine operation control apparatus characterized by the above.

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