JP6099386B2 - Discharge valve unit and pump system - Google Patents

Description

  The present invention relates to a discharge valve unit and a pump system.

  Conventionally, pump systems are used to pump and drain liquids such as water in various facilities such as water purification plants or dams. The pump system drives the pump by a driving device such as a motor, that is, converts the mechanical energy into the kinetic energy of the liquid, thereby transferring the liquid stored in the storage tank or the like.

  By the way, as a method of controlling the flow rate of the liquid discharged from the pump, control of the valve opening degree of the discharge valve provided in the pipe on the discharge side of the pump, control of the rotational speed of the pump impeller, or blades of the pump impeller Angle control is known. Among these, the flow rate control based on the opening degree of the discharge valve is often used because the equipment becomes simple.

  However, in a gate valve or the like used for a pump discharge valve, a change in loss factor at each opening degree of the valve is large, so that the discharge amount of the pump may greatly change with a slight change in opening degree. For this reason, it is difficult to match the target flow rate (that is, it is difficult to control), the flow rate is not stable, and hunting may occur.

  As a countermeasure, a butterfly valve or a funnel valve (also referred to as a cone valve) may be used as a valve with better flow controllability (openness-loss characteristics are suitable for flow control) than a gate valve. There was room for improvement in stability.

  As a prior art, there is a method of changing the opening / closing speed of a valve by opening / closing the valve with an AC motor that can be controlled by an inverter. More specifically, at a valve opening (in the range of 0 to 40%) where the load torque for turning the valve increases, the valve opens and closes slowly, and the valve opening (valve opening) decreases. In the range of 40 to 100%, the valve is opened and closed quickly.

Japanese Patent No. 3079426

  However, the prior art does not take into consideration stabilization of the flow rate change rate per unit valve opening / closing speed of the valve.

  That is, in actual operation, the flow rate change rate per unit valve opening / closing speed of the valve tends to become unstable. For this reason, flow rate hunting and sudden pressure fluctuations are likely to occur in the liquid supply piping, and stable operation may be difficult.

  In this respect, the conventional technology aims to accurately set and maintain the valve at a desired opening / closing speed, and therefore does not consider stabilizing the flow rate change rate of the liquid per unit valve opening / closing speed of the valve. .

In addition to controlling the valve opening of the discharge valve, there are control of the rotational speed of the pump impeller and control of the blade angle of the pump impeller, etc., but prevent the liquid from flowing backward when the pump is stopped. For this purpose, some kind of valve must be installed. In addition to this, since an inverter device and a complicated blade angle operation mechanism for rotational speed control are required, installation costs are high and maintenance management is complicated, which is difficult in terms of economy.

  The discharge valve unit of the present invention has been made in view of the above problems, and is provided on the discharge side of a pump for pumping and discharging liquid, and opens and closes the valve on the discharge side of the pump and the valve at a variable speed. A driver, and a controller that controls the flow rate of the liquid discharged from the pump by controlling the opening and closing of the valve via the driver.

  Then, the control unit sets the unit valve opening / closing speed of the valve for each opening degree of the valve so that the flow rate change rate of the liquid per unit valve opening / closing speed of the valve is within a preset range. According to the first valve opening / closing speed pattern, the opening / closing of the valve is controlled.

  According to the invention of the present application, the first valve opening / closing speed pattern includes a valve unit for each valve opening so that the flow rate change rate of the liquid per unit valve opening / closing speed of the valve is within a preset range. The valve opening / closing speed is set. And since a control part controls opening and closing of a valve according to a 1st valve opening and closing speed pattern, it can stabilize the flow rate change rate per unit valve opening and closing speed of a valve. As a result, it is possible to suppress hunting of the flow rate in the liquid supply conduit and sudden pressure fluctuations, and to perform stable operation.

Further, the control unit has a rate of change in the flow rate of the liquid per unit valve opening / closing speed of the valve within an allowable range as equipment (for example, 0.6 to 1.0 ((m ³ / min) / (sec The opening / closing of the valve can be controlled according to a first valve opening / closing speed pattern in which the opening / closing speed of the valve is set for each opening of the valve.

  Further, the control unit is configured such that the pump is in a normal operation, whether the pump is in a series of start operations up to a normal operation in response to a start signal, or the pump is in a stop operation in response to a stop signal. It is possible to determine whether a series of stop operations are performed.

  When the control unit determines that the pump is in a normal operation, the control unit controls the opening and closing of the valve according to the first valve opening / closing speed pattern, and the pump performs a start operation or a stop operation. If it is determined that the valve opening speed is within the first range for the first valve opening area, the second valve opening area is larger than the first valve opening area. The opening / closing of the valve can be controlled in accordance with a second valve opening / closing speed pattern in which a valve opening / closing speed in a second range smaller than the valve opening / closing speed in the first range is set.

  That is, since the pump is designed to have the highest efficiency in the rated specification, vibration and impeller damage such as cavitation are likely to occur in a small water volume region (small opening region). For this reason, it is preferable to avoid operation in a small water volume region as much as possible in order to extend the life. In particular, in pump facilities that are frequently started up, the accumulated time of operation in a small water amount region during the start / stop operation of the pump becomes long, and damage to the impeller can be a problem. In contrast, according to the present invention, when the pump is started or stopped, the valve opening / closing speed within the first range in the first valve opening range (small opening range) is set to the second valve opening range. Since the valve opening / closing speed is set to be larger than the valve opening / closing speed in the second range in the opening range (large opening range), the operation time of the pump in the small water volume range (small opening range) can be shortened. As a result, it is possible to shorten the accumulated operation time in the small water amount region during the start / stop operation of the pump, and thus it is possible to suppress the occurrence of damage to the impeller.

  Moreover, when the said control part determines with the said pump performing the starting driving | operation or the stop driving | operation, with respect to the 1st valve opening area | region where the opening degree of the said valve is less than the opening degree of 20 degrees-40 degrees A valve opening / closing speed within a first range is set, and a valve opening / closing within a second range that is smaller than the valve opening / closing speed within the first range with respect to the second valve opening range greater than or equal to the predetermined opening degree. According to the second valve opening / closing speed pattern in which the speed is set, the opening / closing of the valve can be controlled.

  In addition, when the battery power source for driving the opening and closing of the valve is provided, the control unit determines whether the pump is in a normal operation or whether the pump is in an emergency stop operation in response to an emergency stop signal. be able to.

  In this case, when it is determined that the pump is operating normally, the opening / closing of the valve is controlled according to the first valve opening / closing speed pattern, and it is determined that the pump is operating in an emergency stop. The valve opening / closing speed within a third range is set for the third valve opening region, and the third valve opening region is larger than the third valve opening region. According to a third valve opening / closing speed pattern in which a fourth valve opening / closing speed larger than the valve opening / closing speed is set, the valve is controlled to close using the battery power source, and the valve can function as a check valve. .

  That is, for example, when a pump trip occurs due to a power failure of the pump facility, the fourth valve opening region (large opening region) is within the third range in the third valve opening region (small opening region). The valve is controlled to close by a valve opening / closing speed within a fourth range that is larger than the valve opening / closing speed of the valve. Thus, when a pump trip occurs, the valve is rapidly controlled to close in the fourth valve opening region (large opening region), and in the third valve opening region immediately before the valve is completely closed. Can prevent the valve body from being suddenly closed by gently closing the valve, thereby preventing damage to the valve body.

  Further, the control unit determines that the pump is in an emergency stop operation, and if the opening degree of the valve is in the fourth valve opening degree region, the valve within the fourth range is used. When the valve is controlled to close according to the opening / closing speed, and the opening of the valve is closed to the third valve opening range, the opening of the valve is closed for a predetermined time with the opening when the valve is closed to the third valve opening range. The closing control is stopped, and after a predetermined time has elapsed, the valve can be controlled to close according to the third valve opening / closing speed.

  According to this, even if a water hammer action occurs due to a pump trip and a pressure increase in the pipe occurs, the valve closing control is stopped for a predetermined time when the valve opening is closed to the third valve opening region. Therefore, during this time, the pressure on the pump discharge side can be released to the pump suction side. As a result, an increase in pressure on the pump discharge side can be suppressed, so that damage to the liquid feeding pipe can be prevented.

  Further, in the case of providing a battery power supply that supplies power to the control unit in the event of a power failure, the control unit determines whether the pump is in normal operation, whether the pump is in start operation in response to a start signal, or the pump It is possible to determine whether the pump is in a stop operation in response to a stop signal or whether the pump is in an emergency stop operation in response to an emergency stop signal due to a power failure.

And when the said control part determines with the said pump operating normally, it controls opening and closing of the said valve according to a said 1st valve opening and closing speed pattern. In addition, when the control unit determines that the pump is performing a start operation or a stop operation, a valve opening / closing speed within a first range is set for the first valve opening region, and the first A second valve opening / closing speed pattern in which a valve opening / closing speed within a second range smaller than the valve opening / closing speed within the first range is set with respect to a second valve opening degree area larger than one valve opening degree region. In accordance with the control, the opening and closing of the valve is controlled. In addition, when the control unit determines that the pump is in an emergency stop operation, a valve opening / closing speed within a third range is set with respect to the third valve opening range, and the third According to a third valve opening / closing speed pattern in which a valve opening / closing speed within a fourth range larger than the valve opening / closing speed within the third range is set with respect to a fourth valve opening degree area larger than the valve opening degree region. The valve is controlled to close using the battery power source, and the valve functions as a check valve.

  The pump system according to the present invention is provided on a liquid tank for storing liquid, a pump for pumping and discharging the liquid stored in the liquid tank, a driver for driving the pump, and a discharge side of the pump. And any one of the above-described discharge valve units.

  According to the present invention, since the rate of change of the flow rate of the liquid per unit valve opening / closing speed of the valve can be stabilized, hunting of the flow rate in the liquid supply pipe and rapid pressure fluctuation can be suppressed, It is possible to prevent the pump impeller from being damaged.

FIG. 1 is a diagram illustrating an overall configuration of a pump system according to the present embodiment. FIG. 2 is a diagram illustrating an example of a flow rate control characteristic (at an assumed condition) of the pump used in the present embodiment. FIG. 3 is a diagram illustrating an example of a valve opening speed pattern and a flow rate change rate per unit valve opening speed in the comparative example. FIG. 4 is a diagram illustrating an example of the flow rate change amount due to the change in the opening degree of the discharge valve and an example of the flow rate change rate. FIG. 5 is a diagram illustrating an example of a first valve opening / closing speed pattern and a flow rate change rate per unit valve opening / closing speed in the first embodiment. FIG. 6 is a diagram illustrating another example of the first valve opening / closing speed pattern and the flow rate change rate per unit valve opening / closing speed in the first embodiment. FIG. 7 is a flowchart of the flow rate control of the pump in the first embodiment. FIG. 8 is a diagram illustrating an example of a second valve opening / closing speed pattern in the second embodiment. FIG. 9 is a diagram for explaining the minimum flow of the pump. FIG. 10 is a flowchart of the flow rate control of the pump in the second embodiment. FIG. 11 is a diagram illustrating an example of a third valve opening / closing speed pattern in the third embodiment. FIG. 12 is a diagram illustrating an example of a time chart of valve opening / closing control in the third embodiment. FIG. 13 is a flowchart of the flow control of the pump in the third embodiment.

  Hereinafter, a discharge valve unit and a pump system according to an embodiment of the present invention will be described with reference to the drawings. Although the following embodiment demonstrates the pump system which pumps up and discharges the water currently stored in the water tank in the water purification plant, and the discharge valve unit installed in the pump system as an example, it is not restricted to this. In addition, the present invention can also be applied to facilities for pumping and draining liquids (for example, discharge valves from upstream water tanks such as dams).

  FIG. 1 is a diagram illustrating an overall configuration of a pump system according to the present embodiment. The pump system 1000 according to the present embodiment includes an operation room 100, an electric room 200, and pump equipment 300.

  In the operation room 100, a monitoring console 102 and a server 104 are installed.

  The monitoring console 102 has an output interface (display) for the operator to monitor the pumping / drainage state of the pump facility 300, and an input interface (keyboard, touch panel, etc.) for the operator to input commands for pumping / draining. ).

  The server 104 performs data processing for display on the monitoring console 102 and appropriately processes a command signal input from the monitoring console 102 and outputs the command signal to the electrical room 200.

  In the electric room 200, an uninterruptible power supply 202 and a power distribution / operation control panel 210 are installed.

  The uninterruptible power supply 202 is a power supply device that supplies power to the power distribution / operation control panel 210 in the event of a power failure. The power distribution / operation control panel 210 normally operates with electric power supplied from the power transmission network via the substation, and operates with electric power supplied from the uninterruptible power supply 202 during a power failure.

  The power distribution / operation control panel 210 includes a pump control unit 212 that controls various pumps provided in the pump facility 300 and a valve control unit 214 that controls opening and closing of various valves provided in the pump facility 300. The power distribution / operation control panel 210 performs various controls on other auxiliary machines in addition to various pumps and various valves provided in the pump facility 300. Details of the pump control unit 212 and the valve control unit 214 will be described later.

  The pump facility 300 is provided with a machine-side operation panel 310, a suction water tank 320, and various devices for pumping and draining water stored in the suction water tank 320.

  The machine-side operation panel 310 is an input interface (keyboard, touch panel, etc.) through which an operator at the pump station inputs commands for pumping and draining. The command signal input to the machine side operation panel 310 is output to the power distribution / operation control panel 210 and is appropriately processed in the power distribution / operation control panel 210.

  The suction water tank 320 is a tank that stores water used in the water purification plant.

  Various devices for pumping and discharging the water stored in the suction water tank 320 include a pump 330 and an electric motor 332, a discharge valve 334 and a motor 336, a vacuum pump 340 and an electric motor 342, an intake valve 344 and a motor 346. The pump facility 300 is provided with two pumping and draining systems using these various devices. Since the two pumping and draining systems have the same configuration, the same reference numerals are given and explanation of one is omitted.

  First, the pump control unit 212 and the valve control unit 214 will be described. The pump control unit 212 outputs a pump control signal for controlling the operation of the pump 330 to the electric motor 332 based on the command signal output from the server 104 or the machine-side operation panel 310. Further, the pump control unit 212 outputs a vacuum pump control signal for controlling the operation of the vacuum pump 340 to the electric motor 342 based on a command signal output from the server 104 or the machine-side operation panel 310.

  The valve control unit 214 outputs a discharge valve control signal for controlling the opening / closing of the discharge valve 334 to the motor 336 based on the command signal output from the server 104 or the machine-side operation panel 310. Further, the valve control unit 214 outputs an intake valve control signal for controlling the opening / closing of the intake valve 344 to the motor 346 based on a command signal output from the server 104 or the machine-side operation panel 310. The valve control unit 214 controls the flow rate of the pump 330 by controlling the opening and closing of the discharge valve 334 via the motor 336.

  The electric motor 332 drives the pump 330 based on the pump control signal transmitted from the pump control unit 212. Further, the electric motor 342 drives the vacuum pump 340 based on the vacuum pump control signal transmitted from the pump control unit 212.

  A water absorption pipe 331 that connects the inside of the suction water tank 320 and the pump 330 is connected to the pump 330. The pump 330 is connected to a water supply pipe 333 that communicates the pump 330 with other facilities (not shown). The pump 330 is driven by the electric motor 332 to pump up water stored in the suction water tank 320 through the water absorption pipe 331 and transfer the pumped water to another facility through the water supply pipe 333.

  In addition, an intake pipe 341 that connects the pump 330 and the vacuum pump 340 is connected to the pump 330. The vacuum pump 340 operates based on the vacuum pump control signal transmitted from the pump control unit 212. More specifically, the vacuum pump 340 fills the pump 330 with water by sucking air inside the pump 330 and the water absorption pipe 331 during the start-up operation of the pump 330.

  An intake valve 344 is provided in the intake pipe 341. The intake valve 344 is a valve that opens and closes the intake pipe 341. The intake valve 344 is provided with a motor 346 that opens and closes the intake valve 344. The motor 346 controls the opening / closing of the intake valve 344 based on the intake valve control signal transmitted from the valve control unit 214.

  A discharge valve 334 is provided in the water supply pipe 333. The discharge valve 334 is a valve whose opening degree of the water supply pipe 333 can be adjusted, such as a butterfly valve, a gate valve, and a cone (funnel) valve. The discharge valve 334 is provided on the discharge side of the pump 330.

  The discharge valve 334 is provided with a motor (driver) 336 that opens and closes the discharge valve 334 at a variable speed. The motor 336 controls opening and closing of the discharge valve 334 based on the valve control signal transmitted from the valve control unit 214. Note that the discharge valve unit 350 is configured by the discharge valve 334, the motor 336, and the valve control unit 214.

<First Embodiment>
Here, the first embodiment of the control by the valve control unit 214 will be described, but before that, the flow rate control characteristics of the pump used in this embodiment and a comparative example will be described. FIG. 2 is a diagram illustrating an example of a flow rate control characteristic of the pump used in the present embodiment. FIG. 3 is a diagram illustrating an example of a valve opening / closing speed pattern and a flow rate change rate per unit valve opening speed in a comparative example.

In FIG. 2, the horizontal axis represents the flow rate (m ³ / min) of the pump 330, and the vertical axis represents the head (m). A graph 401 is an example of a QH curve of the pump 330 used in the present embodiment. Graphs 402 to 409 are examples of resistance curves when the opening degree of the discharge valve 334 is 20 °, 30 °, 40 °, 50 °, 60 °, 70 °, 80 °, and 90 °, respectively. . The intersection of the graph 401 and the graphs 402 to 409 is the operating point of the pump 330. A comparative example of the flow rate change rate of the pump 330 when the valve opening / closing speed of the discharge valve 334 is fixed in the pump 330 having such flow rate control characteristics will be described below.

  In FIG. 3, the horizontal axis is the valve opening degree of the discharge valve 334. In FIG. 3, the vertical axis on the left is the flow rate change rate of the pump 330 per unit valve opening / closing speed of the discharge valve 334, and the graph 410 corresponds to this. In FIG. 3, the vertical axis on the right side is the valve opening / closing speed of the discharge valve 334, and the graph 420 corresponds to it.

FIG. 3 shows a flow rate change rate of the pump 330 when the valve opening / closing speed of the discharge valve 334 is fixed at 2 sec / °, that is, about 0.50 (° / sec) (in other words, as shown in the graph 420) 334 is a simulation of the flow rate of water per unit valve opening / closing speed (334).

  Here, the flow rate change rate of water per unit valve opening / closing speed of the discharge valve 334 will be described. FIG. 4 is a diagram illustrating an example of the flow rate change amount due to the change in the opening degree of the discharge valve and an example of the flow rate change rate.

Table 430 in the drawing shows how much the flow rate of water per minute has changed when the valve opening of the discharge valve 334 is changed. For example, as shown in Table 430 in the figure, when the valve opening is changed from 90 ° to 80 °, the flow rate of water per minute changes by 0.1 (m ³ / min).

On the other hand, the table 440 in the figure shows that, for example, the representative opening when the valve opening is changed from 90 ° to 80 ° is determined as 85 °, and the flow rate change amount at this representative opening is expressed as the valve opening / closing speed (2 sec. The flow rate change rate is obtained by dividing by / °. For example, for a representative opening of 85 °, the flow rate change amount is 0.1 (m ³ / min) and the valve opening / closing speed is 2 (sec / °), so the flow rate change rate is 0.1 / 2. = 0.05 ((m ³ / min) / (sec / °)). Table 440 shows values when the valve opening / closing speed is a constant speed (3 minutes from fully open to fully closed) regardless of the valve opening degree of the discharge valve 334. A graph 410 is formed by plotting the flow rate change rate at each representative opening.

As shown in FIG. 3, when the valve opening / closing speed of the discharge valve 334 is fixed, as shown in the graph 410, the flow rate change rate of the pump 330 is not stable and is about 0 to about 2.3 ((m ³ / min ) / (Sec / °)).

  Thus, when the flow rate change rate of the pump 330 becomes unstable, hunting of the flow rate in the water supply pipe 333 and rapid pressure fluctuation are likely to occur, and stable operation of the pump system may be difficult. Even when the valve opening / closing speed of the discharge valve 334 is set to another value, the flow rate change rate of the pump 330 varies greatly as in FIG. 3 if the valve opening / closing speed is fixed.

  On the other hand, FIG. 5 is a diagram showing an example of the first valve opening / closing speed pattern and the flow rate change rate per unit valve opening speed in the first embodiment.

  In FIG. 5, the horizontal axis represents the valve opening degree of the discharge valve 334. In FIG. 5, the vertical axis on the left is the flow rate change rate of the pump 330 per unit valve opening / closing speed of the discharge valve 334, and the graph 510 corresponds to this. In FIG. 5, the vertical axis on the right side is the valve opening / closing speed of the discharge valve 334, and the graph 520 corresponds to it.

  As shown in FIG. 5, in the first embodiment, the valve opening / closing speed of the discharge valve 334 is not fixed, but is set to a different value for each valve opening. That is, in the first embodiment, in the range of the valve opening of about 20 ° to about 70 °, the valve opening / closing speed is made less than about 0.25 (° / sec), and the valve opening of about 70 ° to about 80 °. In this range, the valve opening / closing speed is about 0.5 (° / sec), and in the valve opening range of about 80 ° to about 90 °, the valve opening / closing speed is about 2.0 (° / sec).

As a result, as shown in the graph 510, the flow rate change rate per unit valve opening speed of the discharge valve 334 is stabilized at about 0.8 ((m ³ / min) / (sec / °)).

In other words, the flow rate change rate per unit valve opening / closing speed of the discharge valve 334 is stabilized at a certain value (for example, 0.8 ((m ³ / min) / (sec / °))). This means that the opening / closing speed of the valve for each opening is set in advance. The valve opening / closing speed (graph 520) for each opening degree of the discharge valve 334 set in advance forms a first valve opening / closing speed pattern.

In this embodiment, the valve 330 is opened and closed for each opening degree of the discharge valve 334 so that the flow rate change rate of the pump 330 is stabilized at about 0.8 ((m ³ / min) / (sec / °)). Although the example which sets speed is shown, it is not restricted to this. For example, the flow rate change rate per unit valve opening / closing speed of the discharge valve 334 is within a preset range (for example, 0.2 to 2.4 ((m ³ / min) / (sec / °))). Thus, the valve opening / closing speed can be set for each opening degree of the discharge valve 334. In addition, the discharge valve 334 has a flow rate change rate of the pump 330 per unit valve opening / closing speed of the discharge valve 334 of 0.4 to 1.6 ((m ³ / min) / (sec / °)). It is preferable to set the opening / closing speed of the valve for each opening.

  When performing the opening / closing control of the discharge valve 334, the valve control unit 214 controls the opening / closing of the discharge valve 334 in accordance with a preset first valve opening / closing speed pattern.

  Therefore, according to this embodiment, the flow rate change rate of water per unit valve opening / closing speed of the discharge valve 334 can be stabilized. As a result, hunting of the flow rate in the water supply pipe 333 and rapid pressure fluctuation can be suppressed, so that stable operation of the pump system can be achieved.

  In the example of FIG. 5, the first valve opening / closing speed pattern in which the valve opening / closing speed differs stepwise for each opening degree of the discharge valve 334 is used, but the present invention is not limited to this. FIG. 6 is a diagram illustrating another example of the first valve opening / closing speed pattern and the flow rate change rate per unit valve opening / closing speed in the first embodiment. For example, as shown in a graph 530 in FIG. 6, the first valve opening / closing speed pattern can be set to change smoothly. The first valve opening / closing speed pattern may be stored as a graph, a table, or the like, or may be stored as an approximate curve or a function.

  Further, in a pump facility having a large actual head variation, the flow rate change rate may be affected by the actual head, so it is preferable to set the opening / closing speed as a function with the actual head as a variable. In this case, the intake / discharge water level (or pressure) is measured and input to the valve control unit 214, and the actual head is calculated from the water level difference (pressure difference) by the valve control unit 214, and controlled by the set value. Can do.

  Next, a method for controlling the flow rate of the pump in the first embodiment will be described. FIG. 7 is a flowchart of the flow rate control of the pump in the first embodiment.

  First, the valve control unit 214 receives a pump start command (step S101). Then, the valve control unit 214 controls the intake valve 344 to “open” (step S102). Specifically, the valve control unit 214 outputs a signal for controlling the intake valve 344 to “open” to the motor 346. The motor 346 drives the intake valve 344 to “open” based on the control signal.

  Subsequently, the pump control unit 212 activates the vacuum pump 340 (step S103). Specifically, the pump control unit 212 outputs a signal for starting the vacuum pump 340 to the electric motor 342. The electric motor 342 activates the vacuum pump 340 based on the control signal.

  Thus, by starting the vacuum pump 340 with the intake valve 344 being “open”, the air inside the pump 330 and the water absorption pipe 331 is gradually sucked, and the pump 330 is filled with water.

  Subsequently, the valve control unit 214 and the pump control unit 212 determine whether or not the pump 330 is full (step S104). When it is determined that the pump 330 is not full (No at Step S104), the valve control unit 214 and the pump control unit 212 repeat the process at Step S104.

  On the other hand, when it is determined that the pump 330 is full (Yes in Step S104), the valve control unit 214 and the pump control unit 212 control the intake valve 344 to be “closed” and stop the vacuum pump 340 (Step S104). S105).

  Subsequently, the pump control unit 212 starts the starting operation of the pump 330 (step S106). Specifically, the pump control unit 212 outputs a signal for starting the pump 330 to the electric motor 332. The electric motor 332 starts the starting operation of the pump 330 based on the control signal.

  Subsequently, the valve control unit 214 determines whether or not the start-up operation of the pump 330 has been completed (step S107). If the valve control unit 214 determines that the start-up operation of the pump 330 is not completed (No at Step S107), the process of Step S107 is repeated.

  On the other hand, when it is determined that the start-up operation of the pump 330 has ended (step S107, Yes), the valve control unit 214 determines whether a command for the valve opening or the target flow rate has been received (step S108). If the valve control unit 214 determines that the command for the valve opening degree or the target flow rate has not been received (step S108, No), the process of step S108 is repeated.

  On the other hand, when it is determined that the valve opening degree or target flow rate command has been received (step S108, Yes), the valve control unit 214 controls the opening / closing of the discharge valve 334 based on the first valve opening / closing speed pattern (step S108). S109).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 has reached the target opening, or whether or not the discharge flow rate of the pump 330 (discharge flow rate of the discharge valve 334) has reached the target flow rate (step S110). ).

  When the valve control unit 214 determines that the discharge valve 334 has not reached the target opening and the discharge flow rate of the pump 330 has not reached the target flow rate (No in step S110), the valve control unit 214 returns to step S109, and The opening / closing control of the discharge valve 334 based on the one valve opening / closing speed pattern is performed.

  On the other hand, if the valve control unit 214 determines that the discharge valve 334 has reached the target opening degree or the discharge flow rate of the pump 330 has reached the target flow rate (Yes in step S110), the valve control unit 214 returns to step S108 and opens the valve. Wait for a new command of degree or target flow.

  As described above, according to this embodiment, it is possible to stabilize the flow rate change rate of the liquid per unit valve opening / closing speed of the valve. That is, in the case of the conventional discharge valve control, as shown in FIG. 3, the flow rate change rate varies greatly depending on the opening degree of the discharge valve 334, and even if the feedback control is applied to the target flow rate, the flow rate is quite stable. May not. On the other hand, as in this embodiment, the first valve opening / closing speed pattern is set in advance so that the flow rate change rate becomes substantially constant, and the discharge valve is set based on the first valve opening / closing speed pattern. By controlling the opening / closing of 334, more stable discharge valve control (without flow rate hunting) becomes possible. As a result, hunting of water in the water supply pipe 333 and rapid pressure fluctuation can be suppressed, so that stable operation of the pump system can be achieved.

  Furthermore, in pumps used for advanced processing etc., sudden changes in the discharge flow rate have problems such as undulations, affecting the processing equipment on the discharge side, and expensive equipment such as rotational speed control was required. However, according to the present embodiment, the flow rate change rate can be easily kept constant, and it is possible to cope with inexpensive valve control.

Second Embodiment
As in the first embodiment, in the second embodiment, in addition to controlling the opening and closing of the discharge valve 334 based on the first valve opening / closing speed pattern, the pump 330 is performing a start operation or a stop operation. In this method, the opening / closing of the discharge valve 334 is controlled based on the second valve opening / closing speed pattern. A description of portions overlapping with the first embodiment will be omitted as appropriate.

  FIG. 8 is a diagram illustrating an example of a second valve opening / closing speed pattern in the second embodiment. In FIG. 8, the horizontal axis represents the valve opening degree of the discharge valve 334, and the vertical axis represents the valve opening / closing speed (° / sec) of the discharge valve 334.

  As shown in a graph 610 in FIG. 8, a valve opening / closing speed of about 2.0 (° / sec) is set for the first valve opening range (0 ° to about 20 °) of the discharge valve 334. ing. Further, for a second valve opening region (about 20 ° to 90 °) larger than the first valve opening region, about 0.5 (° smaller than the valve opening / closing speed in the first valve opening region. / Sec) valve opening / closing speed is set.

  In this way, the valve opening / closing speed (graph 610) for each opening degree of the discharge valve 334 set in advance forms a second valve opening / closing speed pattern.

  The valve control unit 214 determines whether the pump 330 is performing a normal operation, whether the pump 330 is performing a start operation according to a start signal, or whether the pump 330 is performing a stop operation according to a stop signal. The valve control unit 214 controls opening / closing of the discharge valve 334 according to the first valve opening / closing speed pattern during normal operation of the pump 330, and according to the second valve opening / closing speed pattern during start-up operation or stop operation. The opening and closing of the discharge valve 334 is controlled.

  The start operation is an operation from the state where the pump 330 is stopped until the pump 330 is started and the discharge valve 334 is fully closed to fully open. The stop operation is an operation from the state in which the pump 330 is operated until the discharge valve 334 is fully closed and the pump 330 is stopped. On the other hand, the normal operation is an operation until the stop operation is performed after the start operation is completed.

  According to the present embodiment, the operation time of the discharge valve 334 in the small water amount region (small opening region) can be shortened, and the cumulative operation time in the small water region during the start / stop operation of the pump 330 is shortened. Therefore, the occurrence of damage to the impeller can be suppressed. In other words, pumps are generally designed to have the highest efficiency in the rated specifications, and in a small water volume range (small opening range), vibration and impeller damage such as cavitation are likely to occur. Therefore, it is preferable to avoid operation in a small water volume region as much as possible in order to extend the life. In addition to this, when starting or stopping the pump, it is often started and stopped to prevent sudden changes in flow rate, water hammer, and overpower of the drive machine. May not be avoided. In particular, in pump facilities that are frequently started up, the accumulated time of operation in a small water amount region during the start / stop operation of the pump becomes long, and damage to the impeller can be a problem. On the other hand, in the present embodiment, when the pump 330 is started or stopped, the valve opening / closing speed within the first range in the first valve opening region (small opening region) is set to the second value. Since the valve opening / closing speed is set to be larger than the valve opening / closing speed in the second range in the valve opening region (large opening region), the operation time of the pump 330 in the small water amount region (small opening region) can be shortened.

This point will be described in more detail. FIG. 9 is a diagram for explaining the minimum flow of the pump. In FIG. 9, the horizontal axis indicates the flow rate (m ³ / h) of the pump 330, and the vertical axis indicates the total head (m), the pump efficiency (%), and the required NPSH (effective suction head) required by the pump ( m).

  The pump 330 moves on the performance curve 620 in the order of (1) → (2) → (3) (rated point) when the pump 330 is started, and (3) (rated point) when the pump 330 is stopped. Move on the performance curve 620 in the order of (2) → (1). Further, as shown in FIG. 9, the pump efficiency 630 is low in the operation region where the flow rate is smaller than the minimum flow 640 and is high in the operation region exceeding the minimum flow. Furthermore, the required NPSH 650 required by the pump is higher in the region beyond the rated point 660.

  When the flow rate of the pump is controlled by a valve or the like, a minimum flow that can be continuously operated is set. Operating the pump below the minimum flow causes cavitation, noise and vibration, and shortens the pump life. The minimum flow is usually 40 to 60% of the rated flow rate, and the pump must be operated at a minimum flow or higher. Cavitation is a phenomenon in which a part of the liquid is vaporized in the flowing liquid, resulting in a cavity. The static pressure is locally reduced to the saturated vapor pressure of the pumped liquid at the inlet of the pump impeller. This is a boiling phenomenon in which a large number of fine vapor bubbles are generated. If cavitation continues for a long time, the surface of the impeller and casing may be eroded and damaged.

  According to this embodiment, the time of FIG. 9 (1) → (2) during the start operation of the pump 330 and the time of FIG. 9 (2) → (1) during the stop operation of the pump 330 can be shortened. it can. Therefore, the life of the pump 330 can be extended.

  In addition, when the discharge valve 334 is a cone valve (funnel valve), as shown in FIG. 8, when the discharge valve 334 is fully closed and fully open, the vertical movement is different from the rotational movement of the valve body such as lift operation and seat operation. There is movement. In this case, until the pump is completely closed (sitting state), the pump is subjected to a closed operation (flow rate = 0) for a certain period of time, and damage due to vibration or cavitation becomes a problem. In this respect, according to the present embodiment, in the start operation and stop operation of the pump 330, when the opening degree of the discharge valve 334 is in the vicinity of the fully closed (small opening range), the opening and closing speed of the valve is fast. The time during which cavitation occurs can be shortened.

  In the example of FIG. 8, an example in which the opening / closing speed of the discharge valve 334 changes when the valve opening degree of the discharge valve 334 is about 20 ° is shown, but the present invention is not limited to this. A valve opening / closing speed within the first range is set for a first valve opening region (small opening region) where the opening of the discharge valve 334 is less than, for example, less than 30 °, and the second opening of 30 ° or more. A valve opening / closing speed in the second range smaller than the valve opening / closing speed in the first range can be set for the valve opening degree region (large opening degree region).

  8 shows an example in which the valve opening / closing speed (about 2.0 ° / sec) is fixedly set with respect to the first valve opening range (0 ° to about 20 °) of the discharge valve 334. However, it is not limited to this. For example, the valve opening / closing speed is not fixed to a single value but can be set fluidly within a first range (eg, about 0.5 ° / sec or more and less than about 6.0 ° / sec). it can. Preferably, the first range is about 1.0 ° / sec or more and less than about 4.0 ° / sec, and the valve opening / closing speed can be set fluidly within the first range.

8 shows an example in which the valve opening / closing speed (about 0.5 ° / sec) is fixedly set with respect to the second valve opening range (about 20 ° to 90 °) of the discharge valve 334. However, it is not limited to this. For example, the valve opening / closing speed is not fixed to a single value, but within a second range (eg, about 0
. 1 ° / sec or more and less than about 2.0 ° / sec). Preferably, the second range is about 0.1 ° / sec or more and less than about 1.0 ° / sec, and the valve opening / closing speed can be set fluidly within the second range.

  Next, a pump flow rate control method according to the second embodiment will be described. FIG. 10 is a flowchart of the flow rate control of the pump in the second embodiment.

  Since steps S201 to S206 in the second embodiment are the same as steps S101 to S106 in the first embodiment, description thereof will be omitted.

  After step S206, the valve control unit 214 determines whether a pump stop command has been received (step S207). If it judges with valve control part 214 having received a pump stop command (Step S207, Yes), it will control opening and closing of discharge valve 334 based on the 2nd valve opening and closing speed pattern (Step S208).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 is fully closed (step S209). If the valve control unit 214 determines that the discharge valve 334 is not fully closed (No at Step S209), the valve control unit 214 returns to Step S208 and performs opening / closing control of the discharge valve 334 based on the second valve opening / closing speed pattern.

  On the other hand, if the valve control unit 214 determines that the discharge valve 334 is fully closed (step S209, Yes), the valve control unit 214 considers that the stop motion has ended and ends the process.

  In Step S207, if it judges with valve control part 214 not having received the pump stop command (Step S207, No), it will judge whether the command of valve opening or target flow was received (Step S210). When it is determined that the valve opening degree or target flow rate command has been received (step S210, Yes), the valve control unit 214 controls the opening / closing of the discharge valve 334 based on the first valve opening / closing speed pattern (step S211).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 has reached the target opening, or whether or not the discharge flow rate of the pump 330 (discharge flow rate of the discharge valve 334) has reached the target flow rate (step S212). ).

  When it is determined that the discharge valve 334 has not reached the target opening and the discharge flow rate of the pump 330 has not reached the target flow rate (No in step S212), the valve control unit 214 returns to step S211 and The opening / closing control of the discharge valve 334 based on the one valve opening / closing speed pattern is performed.

  On the other hand, when the valve control unit 214 determines that the discharge valve 334 has reached the target opening degree or the discharge flow rate of the pump 330 has reached the target flow rate (Yes in step S212), the valve control unit 214 returns to step S207 to return to the next command. Wait for.

  In step S210, if the valve control unit 214 determines that the command for the valve opening or the target flow rate has not been received (step S210, No), the valve control unit 214 regards that the starting operation is being performed, and the second valve opening / closing speed. The opening / closing of the discharge valve 334 is controlled based on the pattern (step S213).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 is fully opened (step S214). When the valve control unit 214 determines that the discharge valve 334 is not fully opened (No at Step S209), the valve control unit 214 returns to Step S213 and performs opening / closing control of the discharge valve 334 based on the second valve opening / closing speed pattern.

  On the other hand, if it is determined that the discharge valve 334 is fully opened (step S214, Yes), it is considered that the starting operation has been completed, and the process returns to step S207 to wait for the next command.

  According to the present embodiment, by setting the opening / closing speed at a small opening of the discharge valve 334 to be fast, it is possible to shorten the operation in the small water volume region in question, and to minimize damage due to cavitation, The life of the pump 330 can be extended. In addition, according to the present embodiment, the operation state of the pump 330 is determined, and the control mode of the discharge valve 334 is divided according to the operation state, so that the optimal discharge valve 334 can be controlled in each operation. Because it can, operability and reliability can be improved.

<Third Embodiment>
As in the second embodiment, the third embodiment controls the opening / closing of the discharge valve 334 based on the first or second valve opening / closing speed pattern, and when the pump 330 trips (power is cut off). This controls the opening / closing of the discharge valve 334 based on the third valve opening / closing speed pattern. A description of portions overlapping with the first and second embodiments will be omitted as appropriate.

  FIG. 11 is a diagram illustrating an example of a third valve opening / closing speed pattern in the third embodiment. In FIG. 11, the horizontal axis represents the valve opening degree of the discharge valve 334, and the vertical axis represents the valve opening / closing speed (° / sec) of the discharge valve 334.

  As shown in a graph 710 in FIG. 11, a valve opening / closing speed of about 2.0 (° / sec) is set for the third valve opening region (0 ° to about 20 °) of the discharge valve 334. ing. Further, for a fourth valve opening region (about 20 ° to 90 °) larger than the third valve opening region, the valve opening / closing speed in the third valve opening region is about 4.67 (° / Sec) valve opening / closing speed is set.

  In this way, the valve opening / closing speed (graph 710) for each opening degree of the discharge valve 334 set in advance forms a third valve opening / closing speed pattern.

  The valve control unit 214 determines whether the pump 330 is operating normally or whether the pump 330 is performing an emergency stop operation in response to an emergency stop signal due to a power failure. The valve control unit 214 controls the opening and closing of the discharge valve 334 according to the first valve opening / closing speed pattern during the normal operation of the pump 330, and uses the uninterruptible power supply 202 during the emergency stop operation. The opening / closing of the discharge valve 334 is controlled according to the opening / closing speed pattern. In addition to this, the valve control unit 214 also determines whether the pump 330 is performing a start operation according to the start signal or whether the pump 330 is performing a stop operation according to the stop signal. Alternatively, during the stop operation, the opening / closing of the discharge valve 334 can be controlled according to the second valve opening / closing speed pattern.

  The emergency stop operation is an operation in which the discharge valve 334 is rapidly fully closed in order to stop the pump 330 in an emergency when a power failure occurs while the pump 330 is operating.

According to the present embodiment, for example, when a pump trip occurs due to a power outage of the pump facility, the third valve opening area (small opening area) in the fourth valve opening area (large opening area). The valve closing control is performed at a valve opening / closing speed in the fourth range that is larger than the valve opening / closing speed in the third range. Thus, when a pump trip occurs, the valve is rapidly controlled to close in the fourth valve opening region (large opening region), and in the third valve opening region immediately before the valve is completely closed. Can suppress the generation of impact and impact noise by gently closing the valve. Further, according to the present embodiment, the discharge valve 334 can be caused to function as a check valve by fully closing the discharge valve 334 during the pump trip. As a result, the conventionally used check valve can be omitted, and the system can be simplified.

  In the example of FIG. 11, an example in which the opening / closing speed of the discharge valve 334 changes at a position where the opening degree of the discharge valve 334 is about 20 ° is shown, but the present invention is not limited to this. For example, the opening / closing speed of the discharge valve 334 can be changed in a small opening range where the opening of the discharge valve 334 is 30 ° or less.

  FIG. 11 shows an example in which the valve opening / closing speed (about 2.0 ° / sec) is fixedly set with respect to the third valve opening range (0 ° to about 20 °) of the discharge valve 334. However, it is not limited to this. For example, the valve opening / closing speed is not fixed to one value but can be set fluidly within a third range (for example, about 0.5 ° / sec or more and less than about 4.0 ° / sec). it can.

  FIG. 11 shows an example in which the valve opening / closing speed (about 4.67 ° / sec) is fixedly set with respect to the fourth valve opening range (about 20 ° to 90 °) of the discharge valve 334. However, it is not limited to this. For example, the valve opening / closing speed is not fixed to one value but can be set fluidly in a fourth range (for example, about 1.0 ° / sec or more and less than about 6.0 ° / sec). .

  Next, a time chart of valve opening / closing control in this embodiment will be described. FIG. 12 is a diagram illustrating an example of a time chart of valve opening / closing control in the third embodiment.

  In FIG. 12, the horizontal axis represents the elapsed time (operation time) in the emergency stop operation of the pump 330, and the vertical axis represents the valve opening degree of the discharge valve 334. FIG. 12 is a time chart of the emergency stop operation when the emergency stop command is received when the discharge valve 334 has an opening of 90 ° (in the fourth opening range).

  As shown in the graph 810 of FIG. 12, when receiving the emergency stop command, the valve control unit 214 controls the discharge valve 334 to close at a valve opening / closing speed (about 4.67 ° / sec) within the fourth range. Here, since the discharge valve 334 has a lift operation, the opening degree remains 90 ° during the lift operation. When the lift operation is completed, the valve opening of the discharge valve 334 is rapidly closed from 90 ° to about 20 °. That is, the closing operation of the discharge valve 334 is rapidly performed from 0 second to 20 seconds.

  Subsequently, when the valve opening degree of the discharge valve 334 is closed to about 20 ° (third opening degree region), the valve control unit 214 at this about 20 ° for a predetermined time (20 seconds in the example of FIG. 12). Then, the closing control of the discharge valve 334 is stopped. That is, the small opening degree of the discharge valve 334 is maintained between 20 seconds and 40 seconds.

  Then, the valve control unit 214 controls closing of the discharge valve 334 at a valve opening / closing speed (about 2.0 ° / sec) within the third range after a predetermined time has elapsed. That is, the discharge valve 334 is gently closed from 40 seconds to 60 seconds. Here, since the discharge valve 334 has a sheet operation, the sheet operation of the discharge valve 334 is performed from 50 seconds to 60 seconds.

  According to this embodiment, even if a water hammer action occurs due to a pump trip and a pressure increase in the water supply pipe 333 occurs, the discharge valve 334 is opened when the opening of the discharge valve 334 is closed to the third opening range. In the meantime, the pressure on the discharge side of the pump 330 can be released to the suction side of the pump 330. As a result, an increase in pressure on the discharge side of the pump 330 can be suppressed, so that damage to the water supply pipe 333 can be prevented.

Next, a pump flow rate control method according to the third embodiment will be described. FIG. 13 is a flowchart of the flow control of the pump in the third embodiment.

  Since steps S301 to S306 in the third embodiment are the same as steps S101 to S106 in the first embodiment, description thereof will be omitted.

  After step S306, the valve control unit 214 determines whether a pump emergency stop command due to a pump trip has been received (step S307). When it is determined that the pump emergency stop command has been received (step S307, Yes), the valve control unit 214 controls the opening / closing of the discharge valve 334 based on the third valve opening / closing speed pattern (step S308).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 is fully closed (step S309). When it is determined that the discharge valve 334 is not fully closed (No at Step S309), the valve control unit 214 returns to Step S308 and performs opening / closing control of the discharge valve 334 based on the third valve opening / closing speed pattern.

  On the other hand, when it is determined that the discharge valve 334 is fully closed (step S309, Yes), the valve control unit 214 regards that the emergency stop motion has ended and ends the process.

  In step S307, if it determines with the valve control part 214 not having received the pump emergency stop command (step S307, No), it will determine whether the pump stop command was received (step S310). If it judges with valve control part 214 having received a pump stop command (Step S310, Yes), it will control opening and closing of discharge valve 334 based on the 2nd valve opening and closing speed pattern (Step S311).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 is fully closed (step S312). When it is determined that the discharge valve 334 is not fully closed (No at Step S312), the valve control unit 214 returns to Step S311 and performs opening / closing control of the discharge valve 334 based on the second valve opening / closing speed pattern.

  On the other hand, if the valve control unit 214 determines that the discharge valve 334 is fully closed (step S312, Yes), the valve control unit 214 regards that the stop motion has ended and ends the process.

  In step S310, if it is determined that the pump emergency stop command has not been received (step S310, No), the valve control unit 214 determines whether a valve opening degree or target flow rate command has been received (step S313). . When it is determined that the command for the valve opening or the target flow rate has been received (step S313, Yes), the valve control unit 214 controls the opening / closing of the discharge valve 334 based on the first valve opening / closing speed pattern (step S314).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 has reached the target opening, or whether or not the discharge flow rate of the pump 330 (discharge flow rate of the discharge valve 334) has reached the target flow rate (step S315). ).

  When it is determined that the discharge valve 334 has not reached the target opening and the discharge flow rate of the pump 330 has not reached the target flow rate (No in step S315), the valve control unit 214 returns to step S314, The opening / closing control of the discharge valve 334 based on the one valve opening / closing speed pattern is performed.

  On the other hand, if the valve control unit 214 determines that the discharge valve 334 has reached the target opening degree or the discharge flow rate of the pump 330 has reached the target flow rate (step S315, Yes), the valve control unit 214 returns to step S307 to return to the next command. Wait for.

  In step S313, if the valve control unit 214 determines that the command for the valve opening or the target flow rate has not been received (step S313, No), the valve control unit 214 regards that the starting operation is being performed, and the second valve opening / closing speed. Based on the pattern, the opening / closing of the discharge valve 334 is controlled (step S316).

  Subsequently, the valve control unit 214 determines whether or not the discharge valve 334 is fully opened (step S317). If the valve control unit 214 determines that the discharge valve 334 is not fully opened (No at Step S317), the valve control unit 214 returns to Step S316 and performs opening / closing control of the discharge valve 334 based on the second valve opening / closing speed pattern.

  On the other hand, if it is determined that the discharge valve 334 is fully opened (step S317, Yes), it is considered that the starting operation has been completed, and the process returns to step S307 to wait for the next command.

  According to the present embodiment, even when a water hammer effect is generated by a pump trip and a pressure rise occurs in the water supply pipe 333, the discharge valve 334 is gently closed in the vicinity of the fully closed state, and the pressure is sucked in. Since it can escape to the side, it is possible to suppress the pressure rise in the water supply pipe 333 and prevent the water supply pipe 333 from being damaged. Moreover, by using a control mechanism that can be arbitrarily set at a variable speed as in this embodiment, it is more reliable by simulation compared to conventional equipment that is difficult to set the opening and closing speed such as a hydraulically-closed check valve. Measures (open / close timing) can be incorporated into the equipment specifications, and safe and reliable equipment can be constructed. In addition, according to the present embodiment, the opening / closing speed of the discharge valve 334 can be reset, so that resetting (opening / closing timing) suitable for the simulation is possible even when there is a change in the amount of water delivered due to additional pumps, increased volume, etc. Thus, a safe and reliable facility can be constructed.

202 Uninterruptible power supply 210 Power distribution / operation control panel 214 Valve control unit (control unit)
300 Pump equipment 320 Suction water tank 330 Pump 331 Water absorption pipe 332 Electric motor 333 Water supply pipe 334 Discharge valve 336 Motor (driver)
350 Discharge valve unit 1000 Pump system

Claims (6)

A discharge valve unit provided on the discharge side of a pump for pumping and discharging liquid,
A valve provided on the discharge side of the pump;
A driver for opening and closing the valve at a variable speed;
A controller that controls the flow rate of the liquid discharged from the pump by controlling the opening and closing of the valve via the driver, and
The control unit sets the unit valve opening / closing speed of the valve for each opening of the valve so that the rate of change in the flow rate of the liquid per unit valve opening / closing speed of the valve is within a preset range. Controlling the opening and closing of the valve according to a first valve opening and closing speed pattern;
Further, the control unit determines whether the pump is in a normal operation, whether the pump is in a start operation according to a start signal, or whether the pump is in a stop operation according to a stop signal. ,
If it is determined that the pump is in normal operation, the opening and closing of the valve is controlled according to the first valve opening and closing speed pattern,
When it is determined that the pump is performing a start operation or a stop operation, a valve opening / closing speed within the first range is set for the first valve opening range, and the first valve opening range is set based on the first valve opening range. According to a second valve opening / closing speed pattern in which a valve opening / closing speed within a second range smaller than a valve opening / closing speed within the first range is set with respect to a large second valve opening range, the opening / closing of the valve is performed. To control the
A discharge valve unit characterized by that. The discharge valve unit of claim 1 ,
When it is determined that the pump is performing a start operation or a stop operation, the control unit determines that the opening degree of the valve is a first valve opening range that is less than a predetermined opening degree of 20 ° to 40 °. A valve opening / closing speed within a first range is set, and a valve opening / closing speed within a second range smaller than the valve opening / closing speed within the first range with respect to the second valve opening degree region greater than the predetermined opening degree is set. To control the opening and closing of the valve according to the second valve opening and closing speed pattern set by
A discharge valve unit characterized by that. A discharge valve unit provided on the discharge side of a pump for pumping and discharging liquid,
A valve provided on the discharge side of the pump;
A driver for opening and closing the valve at a variable speed;
A controller that controls the flow rate of the liquid discharged from the pump by controlling the opening and closing of the valve via the driver, and
The control unit sets the unit valve opening / closing speed of the valve for each opening of the valve so that the rate of change in the flow rate of the liquid per unit valve opening / closing speed of the valve is within a preset range. Controlling the opening and closing of the valve according to a first valve opening and closing speed pattern;
The discharge valve unit further includes a battery power supply for supplying power to the control unit during a power failure,
The control unit determines whether the pump is in a normal operation or whether the pump is in an emergency stop operation in response to an emergency stop signal due to a power failure,
If it is determined that the pump is in normal operation, the opening and closing of the valve is controlled according to the first valve opening and closing speed pattern,
When it is determined that the pump is in an emergency stop operation, a valve opening / closing speed within a third range is set with respect to the third valve opening range, and a larger value than the third valve opening range is set. The battery power supply is used in accordance with a third valve opening / closing speed pattern in which a valve opening / closing speed in a fourth range larger than a valve opening / closing speed in the third range is set for a valve opening range of 4 Closing control of the valve, causing the valve to function as a check valve;
A discharge valve unit characterized by that. The discharge valve unit according to claim 3 ,
When it is determined that the pump is in an emergency stop operation, and the opening degree of the valve is in the fourth valve opening degree region, the control unit determines the valve opening / closing speed within the fourth range. When the valve opening is closed to the third valve opening region, the valve closing control is performed for a predetermined time with the opening when the valve is closed to the third valve opening region. The valve is controlled to close by the valve opening / closing speed within the third range after a predetermined time has elapsed,
A discharge valve unit characterized by that. A discharge valve unit provided on the discharge side of a pump for pumping and discharging liquid,
A valve provided on the discharge side of the pump;
A driver for opening and closing the valve at a variable speed;
A controller that controls the flow rate of the liquid discharged from the pump by controlling the opening and closing of the valve via the driver, and
The control unit sets the unit valve opening / closing speed of the valve for each opening of the valve so that the rate of change in the flow rate of the liquid per unit valve opening / closing speed of the valve is within a preset range. Controlling the opening and closing of the valve according to a first valve opening and closing speed pattern;
The discharge valve unit further includes a battery power supply for supplying power to the control unit during a power failure,
The control unit is configured to determine whether the pump is in a normal operation, whether the pump is in a start operation in response to a start signal, whether the pump is in a stop operation in response to a stop signal, or the pump is out of power. According to the emergency stop signal from
If it is determined that the pump is in normal operation, the opening and closing of the valve is controlled according to the first valve opening and closing speed pattern,
If it is determined that the pump is a starting operation or stopping operation, the valve speed in first range with respect to the first valve opening range is set, than the first valve opening area According to a second valve opening / closing speed pattern in which a valve opening / closing speed within a second range smaller than a valve opening / closing speed within the first range is set with respect to a large second valve opening range, the opening / closing of the valve is performed. Control
If the pump is determined to be an emergency stop operation is set for the third valve opening region third valve speed in a range of a large second than the third valve opening area The battery power supply is used in accordance with a third valve opening / closing speed pattern in which a valve opening / closing speed in a fourth range larger than a valve opening / closing speed in the third range is set for a valve opening range of 4 Closing control of the valve, causing the valve to function as a check valve;
A discharge valve unit characterized by that. A liquid tank for storing liquid;
A pump for pumping and draining the liquid stored in the liquid tank;
A drive for driving the pump;
The discharge valve unit according to any one of claims 1 to 5 , provided on the discharge side of the pump;
A pump system comprising:

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