JP2006070780A - Pump driving method in pump plant, pump driving device and pump plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump driving method in a pump site and a pump driving device, capable of suppressing surging even when a gate is used instead of a discharge valve and an axial-flow pump is used as a pump. <P>SOLUTION: In this pump driving method in the pump plant, a lower end opening of a pump installation hole is communicated with a water channel communicated with a pump suction water tank, and the pump is installed on the pump installation hole. The pump is normally started until the rotational speed of the pump reaches a predetermined rotational speed D preventing a water level of the pump suction water tank from becoming below an emergency pump stop setting water level. Then, the rotational speed is increased to rated speed E at a speed increasing rate which prevents a problem of surging, as indicated in A; is increased at an optimum speed increasing rate per rotational speed preset to prevent the problem of surging in accordance with water channel properties, as indicated in B; or is increased by predetermined amount, kept until a transient phenomenon is stopped and increased again by predetermined amount after the transient phenomenon is stopped, as indicated in C that these steps are repeated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pump operation method, a pump operation device, and a pump station in which a lower end opening of a pump installation hole communicates with a closed section water channel communicating with a pump suction water tank, and a pump is installed in the pump installation hole. It is.

  FIG. 1 is a diagram showing a configuration example of this type of pump station. As shown in the figure, a pump suction water tank 2 is provided in communication with the suction water channel 1, a closed cross-section water channel 3 is provided in communication with the pump suction water tank 2, and a pump installation hole 4 is provided in communication with the closed cross-section water channel 3. It has been. A pump (vertical shaft pump) 5 is installed in the pump installation hole 4, and the pump 5 is driven via a speed reducer 7 by a gas turbine 6 that is a drive machine. A screen 8 is arranged at the boundary between the suction water channel 1 and the pump suction water tank 2. Reference numeral 9 denotes a water level meter that detects the water level in the pump suction water tank 2.

  When the drive unit 6 is activated and the pump 5 is driven via the speed reducer 7 in the pump station having the above-described configuration, the water sucked from the pump suction port 5a is discharged through the discharge valve 10.

JP 2003-293999 A

  In the pump station having the above-described configuration, a high speed flow of the suction water passage has been advanced, and a gas turbine having a short start / stop time has been increasingly adopted for the drive unit 6. As a result, the problem of surging is likely to occur even in a suction channel and a pump suction tank that were not a problem in a conventional pump station. When surging occurs, for example, at the time of start-up, the water level 101 of the pump suction water tank 2 suddenly drops below the emergency stop set water level 102 or less as shown in FIG. 2, and the water level gauge 9 installed in the pump suction water tank 9 However, there is a problem that the water level 103 is detected, and the pump 5 is brought to an emergency stop and cannot be started.

  In order to solve the above problem, there is a method of slowly opening and closing the discharge valve 10, but in a large pump station, a gate may be used instead of the discharge valve 10, and the gate is operated at an intermediate opening for a long time. It is not preferable. Further, when an axial pump is used as the pump 5, the pump cannot be closed, so the pump 5 is started with the valve fully open. If the flow rate cannot be controlled by the valve, the pump discharge amount increases rapidly and surging occurs.

  The present invention has been made in view of the above-described points. A pump operation method for a pump station, a pump operation device, and a pump operation apparatus that can suppress surging even when a gate is used instead of a discharge valve or an axial pump is used as a pump. The purpose is to provide a pump station.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a pump operation method for a pump station having a configuration in which a lower end opening of a pump installation hole is communicated with a water channel communicating with a pump suction water tank, and a pump is installed in the pump installation hole. The pump is normally started up to a predetermined rotational speed at which the water level of the pump suction tank does not fall below the emergency pump stop set water level, and then the speed is increased at a speed increase rate within a range where no surging problem occurs up to the rated rotational speed. It is characterized by doing.

  The invention according to claim 2 is the pump operation method of the pump station where the lower end opening of the pump installation hole is communicated with the water channel communicating with the pump suction water tank, and the pump is installed in the pump installation hole. The pump suction tank is normally started up to a predetermined rotational speed at which the water level does not fall below the emergency pump stop set water level, and then optimized for each preset rotational speed that does not cause surging problems according to the channel characteristics up to the rated rotational speed. The speed is increased at a speed increasing rate.

  The invention according to claim 3 is a pump operation method of a pump station in which a lower end opening of a pump installation hole is communicated with a water channel communicating with a pump suction water tank, and a pump is installed in the pump installation hole. Start the pump normally until the water level in the pump suction tank does not fall below the emergency pump stop set water level, then increase the rotational speed by a predetermined amount, and wait until the transient is settled at that rotational speed. Then, the rotational speed is increased again by a predetermined amount, and this is repeated until the rated rotational speed is reached.

  According to a fourth aspect of the present invention, there is provided a pump operating device of a pump station having a configuration in which a lower end opening of a pump installation hole is communicated with a water channel communicating with a pump suction water tank, and a pump is installed in the pump installation hole. A control device for controlling the start-up and rotation speed, and the control device normally starts the pump to a predetermined rotation speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level; The present invention is characterized in that it has a function of increasing the speed at a speed increase rate that does not cause a problem of surging up to the speed.

  According to a fifth aspect of the present invention, there is provided a pump operating device of a pump station having a configuration in which a lower end opening of a pump installation hole is communicated with a water channel communicating with a pump suction water tank, and a pump is installed in the pump installation hole. A control device for controlling the start-up and rotation speed, and the control device normally starts the pump to a predetermined rotation speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level; It is characterized by having a function of increasing the speed at an optimum speed increasing rate for each certain rotation speed that does not cause a surging problem in accordance with the channel characteristics up to the speed.

  According to a sixth aspect of the present invention, there is provided a pump operating device of a pump station having a configuration in which a lower end opening of a pump installation hole is communicated with a water channel communicating with a pump suction water tank, and a pump is installed in the pump installation hole. A control device for controlling the start-up and rotation speed, and the control device normally starts the pump to a predetermined rotation speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level; It is equipped with a function to increase the rotation speed by a predetermined amount, wait until the transient phenomenon is settled at the rotation speed, and when the transient phenomenon is settled, increase the rotation speed again by a predetermined amount and repeat this until the rated rotation speed is reached. And

  The invention according to claim 7 is a pump station having a configuration in which a plurality of pump installation holes whose lower end openings communicate with a water channel communicating with a pump suction water tank are installed, and a pump is installed in each of the pump installation holes. At least one of the pumps has a different height of the impeller than the other pumps, and the pump operating device according to any one of claims 4 to 6 is used for one or more of the operating devices of each pump. It is characterized by that.

  According to the first and fourth aspects of the present invention, the pump is normally started up to a predetermined rotational speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and then the surging problem does not occur up to the rated rotational speed. Since the speed is increased at a speed increase rate in the range, surging can be suppressed, and problems due to surging, for example, at the time of start-up, the water level of the pump suction water tank suddenly falls below the emergency stop set water level, and the pump stops emergency The problem can be avoided.

  According to the inventions of claims 2 and 5, the pump is normally started up to a predetermined rotation speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and then adjusted to the channel characteristics up to the rated rotation speed, Since the speed is increased at an optimum speed increase rate for each certain rotation speed at which no problem of surging occurs, surging can be suppressed and problems due to surging can be avoided as described above.

  According to the invention described in claims 3 and 6, the pump is normally started up to a predetermined rotational speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and then the rotational speed is increased by a predetermined amount. Wait until the transient is settled at the rotational speed, and when the transient is settled, increase the rotational speed again by a predetermined amount and repeat this until the rated rotational speed is reached. Can be avoided.

  According to the seventh aspect of the present invention, at least one of the pumps has a different height of the impeller than the other pumps, and the operation device of each of the pumps has any one of the fourth to sixth pumps. Since the operation device is used, the pumping start differs depending on the pump, and one or more pumps are operated by any one of the pump operation devices according to claims 4 to 6, so that surging can be suppressed and problems due to surging can be avoided. A pump station that can be avoided can be provided.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, since the structure of the pump station which applies the operating method and operating device of the pump which concerns on this invention is the same as the pump station shown in FIG. 1, the illustration is abbreviate | omitted. In the present embodiment, an example in which the gas turbine 6 is used as the driving machine will be described. FIG. 3 is a diagram showing a control flow at the time of pump start in the pump operating method according to the present invention. This control flow is executed by a control device (not shown). In this pump start control, the interlock operation selection (ST1) in which the rotational speed of the gas turbine is continuously increased until the pump 5 reaches the rated rotational speed (100% rotational speed) and the pump 5 is operated in the gas turbine. There is a management operation selection (ST2) that operates at a self-supporting rotational speed (generally 60% of the rated rotational speed).

  First, the discharge valve 10 is fully opened (ST3), and a start command for the gas turbine 6 is issued (ST4). If either the linked operation selection (ST1) or the management operation selection (ST2) is selected, the 60% rotation speed mode is set (ST5), and the pump 5 does not fall below the emergency pump stop set water level. The speed of the gas turbine 6 is increased. When the rotational speed of the gas turbine 6 reaches 60% of the rated rotational speed (ST6), the start of the gas turbine 6 is completed (ST7). Subsequently, if it is the management operation selection (ST2), the start of the pump is completed as it is (ST8). In the case of linked operation selection (ST1), a speed increase command is issued (ST9), the gas turbine 6 is speeded up (step 10), and when it reaches 100% rotation speed, that is, the rated rotation speed (ST11), the start is completed. (ST12).

  The speed increase of the gas turbine in ST10 will be described with reference to FIG. 4, the point D at which the gas turbine 6 has a self-supporting rotational speed (generally 60% of the rated rotational speed), that is, a predetermined rotational speed at which the water level of the pump suction water tank 2 of the pump 5 does not fall below the emergency pump stop set water level. It has started normally. Then, A shows a case where the speed is increased at a speed increase rate in a range where the problem of surging does not occur until the rated rotational speed is reached, and the speed is increased until reaching the 100% rotational speed E, that is, the rated rotational speed. 1). After reaching point D, B increases at 100% rotation speed E, that is, at the optimum acceleration rate for each predetermined rotation speed that does not cause a surging problem in accordance with the channel characteristics until reaching the rear rated rotation speed. The case is shown (the invention according to claim 2). After reaching point D, C increases the rotational speed by a predetermined amount to 100% rotational speed E, that is, the rear rated rotational speed, and waits until the transient is settled at that rotational speed. The case where the speed is increased again by a predetermined amount and this operation is repeated is shown (the invention according to claim 3).

  The turbine acceleration control shown in FIGS. 4A, 4B, and 4C can achieve the functions of the control device (not shown).

  After reaching the self-supporting rotational speed D, until the rated rotational speed E is reached, any of the methods A, B, and C can be used for the speed increase control in FIG. Can be avoided.

  In the above example, the closed section water channel 3 communicating with the pump suction water tank 2 is provided with one pump installation hole 4 whose lower end opening communicates, and a pump (vertical shaft pump) 5 is installed in the pump installation hole 4. Although the pump operation method and the operation device of the pump station have been described, the configuration of the pump station is not limited to this, and a lower end opening is formed in the closed cross-section water channel 3 communicating with the pump suction water tank 2 as shown in FIG. A plurality of (three in the figure) pump installation holes 4-1, 4-2, 4-3 communicating with each other are provided, and pumps 5-1, 5 are provided in the respective pump installation holes 4-1, 4-2, 4-3. -2 and 5-3 may be used.

  In the pump station of the configuration shown in FIG. 5, the impellers (not shown) of the pumps 5-1, 5-2 and 5-3 installed in the respective pump installation holes 4-1, 4-2 and 4-3. The height position is changed stepwise, {in the figure (the impeller height position of the pump 5-1) <(the impeller height position of the pump 5-2) <(the impeller height position of the pump 5-3) )}, The operation method and the operation device of the pump may be employed for the operation of each of the pumps 5-1, 5-2, and 5-3.

  Although the embodiments of the present invention have been described above, 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. Is possible. For example, in the above example, a gas turbine is used as a driving machine. However, the driving machine is not limited to this and may be a diesel engine or an electric motor using an inverter, a liquid resistor, or the like. Further, in a pump station having a discharge water tank at the tip of the discharge pipe, surging that occurs in the discharge water tank may be a problem. Even in such a case, the pump operation method and the pump operation device according to the present invention may be used. The problem of surging during start-up can be avoided.

It is a figure which shows the structural example of a pump station. It is a figure which shows the case where the water level of the suction tank of a pump station has fallen abnormally. It is a figure which shows the control flow at the time of the pump starting of the pump operation apparatus of the pump station which concerns on this invention. It is a figure which shows the relationship between the pump rotational speed of the pump operating device of the pump station which concerns on this invention, and time. It is a figure which shows the structural example of the pump station which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Suction water channel 2 Pump suction water tank 3 Closed cross-section water channel 4 Pump installation hole 5 Pump 6 Gas turbine 7 Reduction machine 8 Screen 9 Water level meter 10 Discharge valve

Claims (7)

In the pump operation method of the pump station of the configuration in which the lower end opening of the pump installation hole is communicated with the water channel communicating with the pump suction water tank, and the pump is installed in the pump installation hole,
The pump is normally started up to a predetermined rotational speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and then the speed is increased to a rated rotational speed with a speed increase rate within a range where no surging problem occurs. The pump operation method of the pump station characterized by this. In the pump operation method of the pump station of the configuration in which the lower end opening of the pump installation hole is communicated with the water channel communicating with the pump suction water tank, and the pump is installed in the pump installation hole,
The pump is normally started up to a predetermined rotational speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and then a predetermined rotation that does not cause a surging problem according to the channel characteristics up to the rated rotational speed. A pump operation method of a pump station characterized by speeding up at an optimum speed increasing rate for each speed. In the pump operation method of the pump station of the configuration in which the lower end opening of the pump installation hole is communicated with the water channel communicating with the pump suction water tank, and the pump is installed in the pump installation hole,
The pump is normally started up to a predetermined rotational speed at which the water level in the pump suction water tank does not fall below the emergency pump stop set water level, then the rotational speed is increased by a predetermined amount, and waits until the transient phenomenon is settled at that rotational speed, A pump operation method for a pump station, characterized in that when the transient phenomenon has subsided, the rotational speed is increased again by a predetermined amount and this is repeated until the rated rotational speed is reached. In the pump operating device of the pump station of the configuration in which the lower end opening of the pump installation hole is communicated with the water channel communicating with the pump suction water tank, and the pump is installed in the pump installation hole,
A control device for controlling the start-up and rotation speed of the pump;
The control device has a function of normally starting the pump to a predetermined rotational speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and an acceleration rate within a range in which no surging problem occurs up to the rated rotational speed thereafter. The pump operating device of the pump station characterized by having a function to increase the speed at the pump station. In the pump operating device of the pump station of the configuration in which the lower end opening of the pump installation hole is communicated with the water channel communicating with the pump suction water tank, and the pump is installed in the pump installation hole,
A control device for controlling the start-up and rotation speed of the pump;
The control device has a function of starting the pump normally to a predetermined rotational speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and then has a surging problem in accordance with the channel characteristics up to the rated rotational speed. A pump operating device for a pump station, which has a function of increasing the speed at an optimum speed increasing rate for each predetermined rotation speed that does not occur. In the pump operating device of the pump station of the configuration in which the lower end opening of the pump installation hole is communicated with the water channel communicating with the pump suction water tank, and the pump is installed in the pump installation hole,
A control device for controlling the start-up and rotation speed of the pump;
The control device normally starts the pump to a predetermined rotational speed at which the water level of the pump suction water tank does not fall below the emergency pump stop set water level, and then increases the rotational speed by a predetermined amount. A pump operating apparatus of a pump station comprising a function of waiting for a phenomenon to settle, increasing the rotational speed again by a predetermined amount when the transient phenomenon has settled, and repeating this until the rated rotational speed is reached. In the pump station of the configuration in which a plurality of pump installation holes communicating with the lower end opening communicate with a water channel communicating with the pump suction water tank, and a pump is installed in each of the pump installation holes,
At least one of the pumps has a different impeller height than the other pumps,
7. A pump station using one of the pump operating devices according to claim 4 as one or more of the operating devices for each pump.

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