JP2020143626A - Water supply device - Google Patents

Abstract

To provide a water supply device capable of surely performing a back-up operation in failure of a pressure detector.SOLUTION: A water supply device 1 includes an invertor 51 for driving pump devices 11, a plurality of first flow detectors 19 detecting secondary-side flow rates of the plurality of pump devices 11, a first pressure detector 20 disposed at a secondary side of the plurality of pump devices 11, a storage portion 52 for storing a stop flow rate, a maximum operation frequency of the invertor 51, and a rated flow, and a control portion 53 for storing or updating an operation frequency at stop of the inverter 51 in the stop flow rate in the storage portion 52, and controlling the inverter 51 on the basis of a relationship between the flow rates detected by the first flow rate detectors 19 and the operation frequency of the invertor 51, derived from the operation frequency at stop and the maximum operation frequency stored in the storage portion 52, and the operation frequency calculated from the flow rates detected by the first flow rate detectors 19.SELECTED DRAWING: Figure 1

Description

The present invention relates to a water supply device that performs backup operation.

As a water supply device that supplies water to an apartment house or the like, a device that controls the operating frequency of an inverter and controls the drive of the pump device based on the detection value of a pressure detector provided on the secondary side of the pump device is known. ing. Further, for the purpose of energy saving operation, discharge pressure, the rated set pressure P ₁ becomes at the rated flow rate, so that the estimated end pressure P ₂ that defines lower than the rated pressure in stopping the flow, estimated to control the operating frequency of the inverter A water supply device that employs a constant end pressure control method is also known.

Further, as such a water supply device, when the pressure detector fails, a device that shifts to a backup operation in which the pump device is started at a preset time interval is also known.

As a water supply device that performs backup operation when the pressure detector fails, in order to prevent the generation of high pressure and wasteful power consumption during backup operation, the operating frequency of the inverter during backup operation is not set to the maximum frequency, and it is detected during normal operation. Those that operate at the lowest frequency or a frequency obtained by adding a predetermined value to the lowest frequency are known.

Further, as a water supply device that performs a backup operation when a pressure detector fails, a water supply device that continues the operation at a fixed rotation speed without stopping the pump during the backup operation is also known (see, for example, Patent Document 1).

In addition, as a water supply device that performs backup operation when the pressure detector fails, it has a flow sensor that is installed downstream of the pump and transmits a signal when a predetermined flow rate is detected. When the pressure detector fails, the flow sensor A direct water supply device that controls the start of the pump based on the detection result of is also known (see, for example, Patent Document 2). Such a direct water supply device utilizes the fact that the pressure on the suction side of the pump becomes positive due to the pressure in the water pipe even when the pump is stopped, and detects the ON state of the flow sensor while the pump is stopped. , Start the pump as if water supply had occurred.

JP-A-2017-106363 Japanese Unexamined Patent Publication No. 2016-50524

However, when the above-mentioned water supply device is operated with the operating frequency of the pump device fixed at a predetermined value, there is a risk that the pressure will be insufficient in the flow rate region where the amount of water supplied is large.

In the technique of Patent Document 1, if the operation is continued without stopping the pump device during the backup operation when the pressure detector fails, the pump device is operated even in a state where water supply is not generated.

Further, in the technique of Patent Document 2, the above-mentioned direct water supply device does not meet the condition that the pressure on the suction side of the pump is positive and the pressure at the water supply destination is lower than the pressure on the suction side of the pump. , It was not applicable because no water flow was generated.

Therefore, an object of the present invention is to provide a water supply device capable of reliably performing a backup operation when a pressure detector fails.

The water supply device according to the embodiment of the present invention detects a plurality of pump devices having a pump and a motor for driving the pump, an inverter for driving the motor, and a flow rate on the secondary side of each of the plurality of pump devices. a plurality of first flow detector to stop flow rate _{Q 0,} the stop flow rate _Q stop operating frequency _{f 0} of the inverter _0:00, the maximum operating frequency _{f max} of the inverter, and, at the maximum operating frequency _{f max} wherein a storage unit in which the first flow rate detector stores the rated flow Q ₁ which detects the highest of the inverter of the pause time of the operating frequency f ₀ and the rated flow rate to Q ₁ the inverter o'clock the stop flow Q ₀ The target operation is set to the operating frequency based on the relationship between the flow rate detected by the first flow rate detector and the operating frequency of the inverter, which is derived using the operating frequency f _max , and the flow rate detected by the first flow rate detector. calculated as the frequency f _t, and a control unit for controlling the operation frequency of the inverter to the calculated the target operating frequency f _t, the.

According to the present invention, it is possible to provide a water supply device capable of reliably performing a backup operation when a pressure detector fails.

The front view which shows the structure of the water supply device which concerns on one Embodiment of this invention. A side view showing a partial cross-sectional view of the configuration of the water supply device. A side view showing a part of the structure of the water supply device in a partial cross section. It is a modification of the water supply device, and is a front view showing the configuration of the water supply device.

Hereinafter, the water supply device 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 3.
FIG. 1 is a front view showing the configuration of the water supply device 1, FIG. 2 is a side view showing the configuration of the water supply device 1 in a partial cross section, and FIG. 3 is a part of the configuration of the water supply device 1. It is a side view which shows the discharge pipe 12, the check valve 13, and the 1st flow rate detector 19 in a partial cross section.

As shown in FIGS. 1 and 2, the water supply device 1 is provided in each of the plurality of pump devices 11, the plurality of discharge pipes 12 connected to the secondary side of the plurality of pump devices 11, and each discharge pipe 12. A plurality of check valves 13, a plurality of on-off valves 14 provided in each discharge pipe 12, a connecting pipe 15 for connecting the plurality of discharge pipes 12, a connecting pipe 16 provided in the connecting pipe 15, and a connecting pipe 16. A pressure accumulator 17 provided, a relief pipe 18 connected to a plurality of pump devices 11, a plurality of first flow rate detectors 19 for detecting the flow rate on the secondary side of each pump device 11, and a connecting pipe 15 It includes a first pressure detector 20 for detecting pressure, a second flow rate detector 21 for detecting the flow rate flowing from the accumulator device 17 to the connecting pipe 15, and a control panel 22 for controlling the operation of each pump device 11. The water supply device 1 pumps the water from the water source by the pump device 11 and supplies the water to the water supply destination via the discharge pipe 12 and the connecting pipe 15.

As shown in FIGS. 1 and 2, the pump device 11 includes a motor 31 and a pump 32. The primary side of the pump device 11 is connected to the water source. Here, the water source is, for example, a water receiving tank. The pump device 11 is, for example, a so-called vertical multi-stage turbine pump in which a rotating shaft is extended along the direction of gravity and a motor 31 is arranged above the pump 32. For example, three pump devices 11 are provided.

The motor 31 is connected to the pump 32 via a rotating shaft. The motor 31 is electrically connected to the control panel 22.

The pump 32 is driven by the motor 31. The pump 32 has, for example, a suction port 32a and a discharge port 32b on the lower end side. In the pump 32, the suction port 32a is connected to the water receiving tank, and the discharge port 32b is connected to the discharge pipe 12.

As shown in FIG. 2, one end of the discharge pipe 12 is connected to the discharge port 32b of each pump 32, and the other end is connected to the connecting pipe 15. The discharge pipe 12 is extended along the direction of gravity.

As shown in FIGS. 2 and 3, the check valve 13 is provided on the secondary side of the pump 32 and on the primary side of the connecting pipe 15, for example, in each discharge pipe 12. The check valve 13 prevents backflow of water toward the pump 32 in the discharge pipe 12.

As shown in FIG. 2, the on-off valve 14 is provided on the secondary side of the pump 32 and on the primary side of the connecting pipe 15, for example, in each discharge pipe 12. The on-off valve 14 is provided, for example, at a position adjacent to the connecting portion between the discharge pipe 12 and the connecting pipe 15. The on-off valve 14 opens or closes a flow path continuous from the discharge pipe 12 to the connecting pipe 15.

As shown in FIGS. 1 and 2, the connecting pipe 15 connects the other ends of the plurality of discharge pipes 12. Further, the connecting pipe 15 has two open ends on the secondary side of the plurality of connected discharge pipes 12, a closing flange is connected to one end, and a pipe communicating with the water supply destination is connected to the other end. The connecting pipe 15 merges the water that has passed through each discharge pipe 12 and forms a flow path to the secondary side that communicates with the connected pipe.

As shown in FIGS. 1 and 2, the connecting pipe 16 is provided in the connecting pipe 15 and is arranged on the secondary side of the position where the discharge pipe 12 is connected. Further, the connecting pipe 16 is provided with a plurality of pressure accumulators 17. The connecting pipe 16 fluidly connects the plurality of accumulators 17 and the connecting pipe 15.

As shown in FIGS. 1 and 2, a plurality of accumulators 17 are provided in the connecting pipe 16. In this embodiment, two accumulators 17 are provided. The accumulator 17 is fluidly continuous with the connecting pipe 15 via the connecting pipe 16.

As shown in FIGS. 1 and 2, the relief pipe 18 fluidly connects the secondary sides of the plurality of pumps 32 to the water receiving tank. The relief pipe 18 releases a part of the increased pressure in the pump 32 to the water receiving tank to prevent the temperature in each pump 32 from rising.

As shown in FIGS. 2 and 3, the first flow rate detector 19 is provided in each discharge pipe 12. The first flow rate detector 19 is provided, for example, on the secondary side of the pump 32 and on the primary side of the check valve 13 provided in the discharge pipe 12. That is, the first flow rate detector 19 is configured to be able to detect the flow rate on the secondary side of each pump 32. The first flow rate detector 19 is a flow meter that outputs a signal corresponding to the flow rate. The first flow rate detector 19 transmits a signal to the control panel 22. The first flow rate detector 19 is an impeller type flow meter including, for example, a rotating shaft 41, an impeller 42, and a detection unit 43 for detecting the rotation of the impeller 42.

The rotating shaft 41 is arranged in the discharge pipe 12 in a direction in which the axial direction is orthogonal to the water flow direction.

The impeller 42 is fixed to the rotating shaft 41. The impeller 42 rotates the rotating shaft 41 by receiving a water flow passing through the discharge pipe 12.

The detection unit 43 includes, for example, a magnet provided on the rotation shaft 41, a sensor for detecting the rotation of the magnet, and a detection board electrically connected to the sensor. As a specific example, the sensor is a police box detection type Hall IC which is a magnetic detection element. The detection unit 43 converts the rotation of the magnet accompanying the rotation of the rotation shaft 41 into a pulse signal. The detection unit 43 is electrically connected to the control panel 22 via a signal line or the like. The detection unit 43 transmits a pulse signal to the control panel 22.

As shown in FIG. 1, the first pressure detector 20 is provided in the connecting pipe 15. The first pressure detector 20 is configured to be able to detect the pressure in the connecting pipe 15. The first pressure detector 20 is electrically connected to the control panel 22 via a signal line or the like. The first pressure detector 20 is, for example, a pressure gauge that outputs a signal corresponding to the pressure. The first pressure detector 20 converts the detected pressure into a signal and transmits the signal to the control panel 22.

As shown in FIG. 2, the second flow rate detector 21 is provided in the connecting pipe 16 and is arranged between the connecting portion of the connecting pipe 16 and the connecting pipe 15 and the accumulator device 17. That is, the second flow rate detector 21 is configured to be able to detect the flow rate of water flowing from the accumulator 17 to the connecting pipe 15. The second flow rate detector 21 is a flow meter capable of detecting a minute flow rate caused by water supply such as pipe leakage. The second flow rate detector 21 is a flow meter that outputs a signal corresponding to the flow rate. The second flow rate detector 21 transmits a signal to the control panel 22. The second flow rate detector 21 is, for example, an impeller type flow meter including a rotating shaft 41, an impeller 42, and a detection unit 43 for detecting the rotation of the impeller 42, similarly to the first flow detector 19. Is.

As shown in FIG. 1, the control panel 22 includes an inverter 51, a storage unit 52, and a control unit 53.

The inverter 51 is electrically connected to the motor 31 and the control unit 53 via a signal line. For example, the same number of inverters 51 as the motors 31 are provided. In this embodiment, three inverters 51 are provided. The inverter 51 changes the rotation speed of the motor 31 by changing the operating frequency.

In the storage unit 52, the stop flow rate Q ₀ , the maximum operating frequency f _max of the inverter 51, the operating frequency of the inverter 51 is the maximum operating frequency f _max , and the discharge pressure of the pump device 11 is the rated set pressure P. the rated flow rate to Q ₁ when it is _1, stores. The storage unit 52, while the pump device 11 is running, the control unit 53 first flow rate detector 19 from the stop flow Q ₀ the operating frequency and is stopped when the operation frequency f of the inverter 51 when the detected Memorize ₀ .

The stop flow rate Q ₀ is a flow rate at which the pump device 11 is stopped. The stop flow rate Q ₀ is replaced with, for example, the number of pulses n ₀ of the pulse signal output by the first flow rate detector 19 when the flow rate passing through the installation location of the first flow rate detector 19 is the stop flow rate Q ₀ . It is stored in the storage unit 52. Hereinafter, the number of pulses _{n 0,} and stops the flow when the number of pulses _{n 0.}

The rated flow rate Q ₁ is the flow rate of the pump device 11 when the operating frequency of the inverter 51 is the maximum operating frequency f _max and the discharge pressure of the pump device 11 is the rated set pressure P ₁ . The rated flow rate Q ₁ is replaced with, for example, the number of pulses n ₁ of the pulse signal output by the first flow rate detector 19 when the flow rate passing through the installation location of the first flow rate detector 19 is the rated flow rate Q ₁ . It is stored in the storage unit 52. Hereinafter, the number of pulses _{n 1,} and the rated flow rate when the number of pulses _{n 1.}

The control unit 53 detects the number n of pulses of the pulse signal received from the first flow rate detector 19 and the second flow rate detector 21 as the flow rate detection values by the first flow rate detector 19 and the second flow rate detector 21, respectively. To do. Further, the control unit 53 converts the signal received from the first pressure detector 20 into a pressure value as the pressure detected value by the first pressure detector 20. The control unit 53 sets each inverter 51 based on the flow rate and pressure detection values of the first flow rate detector 19, the first pressure detector 20, and the second flow rate detector 21, and the information stored in the storage unit 52. Control the operating frequency of the inverter. Further, the control unit 53 has a first function of determining whether the first pressure detector 20 is out of order or normal, and a second function of performing a normal operation or a backup operation. Hereinafter, the first function and the second function of the control unit 53 will be specifically described.

The first function is a function that the control unit 53 determines that the first pressure detector 20 is out of order when the signal received from the first pressure detector 20 is out of the predetermined signal level range. is there.

As a specific example, a threshold value is stored in the storage unit 52 in advance, and when the pressure detection value by the first pressure detector 20 exceeds the threshold value stored in the storage unit 52 in advance, the control unit 53 detects the first pressure. It is determined that the vessel 20 is out of order. Here, the threshold value can be arbitrarily set, and is, for example, the maximum value and the minimum value of the pressure detection values that can be detected by the normal first pressure detector 20 when the water supply device 1 is in operation.

In the second function, when the control unit 53 determines that the first pressure detector 20 is normal by the first function, the normal operation is performed, and the first pressure detector 20 fails due to the first function. It is a function to perform backup operation when it is determined that there is.

As an operation of the control unit 53 during normal operation, the control unit 53 controls each inverter 51 so that the value detected by the first pressure detector 20 becomes the target pressure. As a specific example, in the control unit 53, each inverter is set so that the target pressure is set by the constant discharge pressure control or the estimated terminal pressure constant control, and the value detected by the first pressure detector 20 becomes the target pressure. 51 is controlled.

Further, when the control unit 53 detects the stop flow rate Q ₀ by the first flow rate detector 19 while executing the normal operation, that is, when the first flow rate detector 19 detects the number of pulses n ₀ at the stop flow rate, It stops the pump device 11, the storage unit 52 the operating frequency of the inverter 51 at this time as a stop during operation frequency f _0. Here, when the storage unit 52 has already stored the stop operation frequency f ₀ , the control unit 53 updates the stop operation frequency f ₀ stored in the storage unit 52.

Further, when the control unit 53 determines that the first pressure detector 20 has failed due to the first function during the normal operation, the control unit 53 shifts to the backup operation.

In this way, the control unit 53 controls each inverter 51 so that the value detected by the first pressure detector 20 becomes the target pressure as an operation during normal operation, and when the stop flow rate is detected, the inverter 51 at that time is controlled. Memorize the operating frequency of. Then, the control unit 53 determines that the first pressure detector 20 has failed, and shifts to the backup operation.

As an operation of the control unit 53 during the backup operation, the control unit 53 starts each pump device 11 at a preset time interval. Specifically, when the pump device 11 is started, the control unit 53 continues the operation of the pump device 11 for the first predetermined time, and after the first predetermined time has elapsed from the start of the pump device 11, When the stop flow rate is detected by the first flow rate detector 19, the pump device 11 is stopped. Here, the first predetermined time is, for example, 10 seconds. Further, when the pump device 11 is stopped, the control unit 53 continues to stop the pump device 11 for a second predetermined time, and after a second predetermined time has elapsed from the stop of the pump device 11, the pump device again. Start 11 Here, the second predetermined time is, for example, 60 seconds. The first predetermined time for continuing the operation of the pump device 11 and the second predetermined time for continuing the stop of the pump device 11 are stored in the storage unit 52 in advance, for example.

Further, the control unit 53 controls the operating frequency of each inverter 51 corresponding to each pump device 11 as described below during the operation of each pump device 11.

First, the control unit 53 uses the stop flow rate Q ₀ stored in the storage unit 52, the maximum operating frequency f _max and the rated flow rate Q ₁ , and the stop operation frequency f ₀ by the first flow rate detector 19. The relationship between the detected flow rate and the operating frequency of the inverter 51 is derived.

Then, the control unit 53, based on the relationship between the operating frequency of the flow rate and the inverter 51 detected by the first flow rate detector 19 derived, the target operating frequency f _t of the flow rate detected by the first flow rate detector 19 inverter 51 Is calculated. Control unit 53, the operating frequency of the inverter 51 is controlled to the calculated target operation frequency f _t.

As a specific example, first, the control unit 53 stops the storage unit 52 stores the flow rate when the number of pulses n _0, maximum operating frequency f _max and rated flow when the number of pulses n _1, and, the stop operation frequency f ₀ The operating frequency of the inverter 51 corresponding to the number n of pulses detected by the first flow detector 19 between the number of pulses n ₀ at the stopped flow rate and the number of pulses n ₁ at the rated flow rate is determined by linear interpolation. Here, the operating frequency of the inverter 51 corresponding to the number of pulses n is such that the operating frequency of the inverter 51 when the first flow detector 19 detects the number of pulses n ₀ at the stopped flow rate is the operating frequency f ₀ at the time of stopping. 1 The operating frequency of the inverter 51 when the flow detector 19 detects the number of pulses n ₁ at the rated flow rate is defined as the maximum operating frequency f _max . Control unit 53, the operating frequency of the inverter 51 corresponding to the pulse number n and the target operating frequency f _t. That is, the control unit 53, a target operating frequency f _t of the inverter 51, as a linear function of the number of pulses n detected by the first flow rate detector 19 is obtained as the target operation frequency f _t1 shown in the following equation (1).

Subsequently, the control unit 53 calculates the target operating frequency _ft1 of the inverter 51 from the number of pulses n of the pulse signal received from the first flow rate detector 19 by using the mathematical formula (1). The control unit 53 controls the operating frequency of the inverter 51 to the calculated target operating frequency _ft1 .

Then, after the first predetermined time has elapsed from the start of the pump device 11, the control unit 53 detects that the number of pulses n detected by the first flow rate detector 19 is n ₀ or less at the stop flow rate. Then, the pump device 11 is stopped. Further, the control unit 53 restarts the pump device 11 when a second predetermined time elapses from the stop of the pump device 11.

Further, the control unit 53 starts the pump device 11 when the flow rate detected by the second flow rate detector 21 is equal to or higher than a predetermined value when the pump device 11 is stopped. Specifically, the storage unit 52 stores a predetermined number of pulses as a predetermined value in advance, and the control unit 53 determines that the number of pulses of the pulse signal received from the second flow rate detector 21 is equal to or greater than the predetermined value. When it is detected, the pump device 11 is started. Here, the predetermined value is, for example, the number of pulses detected by the second flow rate detector 21 when the flow rate is a minute flow rate caused by water leakage from a pipe or the like, and the value is 1 p / sec as an example.

According to the water supply device 1 configured in this way, the relationship between the flow rate detected by the first flow rate detector 19 and the operating frequency of the inverter 51 is derived during the backup operation, and the operating frequency of the inverter 51 is detected by the first flow rate detector. By controlling the operating frequency corresponding to the flow rate detected by the device 19, it is possible to prevent the pressure required for water supply from becoming insufficient while suppressing the generation of high pressure unnecessary for water supply.

Further, in the water supply device 1, as in the above example, the first flow rate detector 19 is used as an impeller type flow rate sensor, and the operating frequency of the inverter 51 during the backup operation is the flow rate detected by the first flow rate detector 19. The operating frequency calculated as a linear function. As a result, the water supply device 1 can control the operating frequency of the inverter 51 during the backup operation so as to approximate the operating frequency of the inverter 51 during the normal operation.

Further, in the water supply device 1, the second flow rate detector 21 is provided in the connection pipe 16 to which the accumulator 17 is connected, so that water flows out from the accumulator 17 even when the pump device 11 is stopped. Can be detected as a state in which water is supplied, and the pump device 11 can be appropriately started. That is, the water supply device 1 can detect the occurrence of water supply and start the pump device 11 to supply water even when the pump device 11 is stopped during the backup operation.

Here, the water supply device 1 is set so that the control unit 53 starts the pump device 11 when the number of pulses of the pulse signal acquired from the second flow rate detector 21 is 1 p / sec or more, as in the above-mentioned example. By doing so, it is possible to detect the flow rate of the water flowing out from the accumulator device 17 for supplying a minute flow rate of water such as pipe leakage and start the pump device 11. That is, the water supply device 1 can start the pump device 11 in response to the occurrence of a minute flow rate of water supply such as pipe leakage while the pump device 11 is stopped during the backup operation.

As described above, according to the water supply device 1 according to the embodiment of the present invention, it is possible to reliably perform the backup operation when the pressure detector fails.

The present invention is not limited to the above embodiment. For example, in the above example, the control unit 53, a target operating frequency f _t of the backup operation time of the inverter 51, an example has been described of calculating as a linear function of the flow rate detected by the first flow rate detector 19, to Not limited.

For example, the control unit 53, a target operating frequency f _t of the backup operation time of the inverter 51, may be calculated as a quadratic function of the flow rate detected by the first flow rate detector 19.

Specifically, during the backup operation, the control unit 53 has the number of pulses at stop flow rate n ₀ , the maximum operating frequency f _{max, the} number of pulses at rated flow rate n ₁ stored by the storage unit 52, and the operation frequency at stop. using f _0, the target operating frequency f _t of the inverter 51 may be configured to calculate as a quadratic function of the number of pulses n detected by the first flow rate detector 19. That is, the control unit 53, a target operating frequency f _t, it may be configured to calculate a target driving frequency f _t2 shown in the following equation (2). Here, the target operating frequency _ft2 of the inverter 51 is such that the operating frequency of the inverter 51 when detecting the number of pulses n ₀ at the stopped flow rate by the first flow rate detector 19 is set to the stopped operating frequency f _0, and the first flow rate is detected. The operating frequency of the inverter 51 when detecting the number of pulses n ₁ at the rated flow rate by the device 19 is defined as the maximum operating frequency f _max .

Even if the target operating frequency _ft is calculated in this way, it is possible to control the operating frequency of the inverter 51 that is close to the operating frequency during normal operation, as in the above-mentioned example.

The control unit 53 includes a target driving frequency f _t1 calculated by Equation (1), a configuration in which the target driving frequency f _t2 and the target operating frequency f _t of the average value of the calculated by Equation (2) May be good. That is, the control unit 53, a target operating frequency f _t, it may be configured to calculate a target driving frequency f _t3 shown in Equation (3) below.

The control unit 53 configured in this way can also control the operating frequency of the inverter 51 that is close to the operating frequency during normal operation, as in the above-described example.

Note that equation (1), Equation (2) and Equation (3) was calculated by the target driving frequency f _t corresponding to a certain flow rate, typically the operating frequency during operation corresponding to the flow rate, the actual respectively As a result of comparison, the calculated value of the target operating frequency _ft3 by the mathematical formula (3) was the closest to the operating frequency during normal operation. Accordingly, the control unit 53, by using the target driving frequency _{f t3} calculated by Equation (3), when using the target operation frequency _{f t1} or target operation frequency _{f t2} is calculated by Equation (1) or formula (2) It can be said that the operating frequency of the inverter 51 can be controlled most closely to the operating frequency during normal operation.

Further, in the above-described example, an example in which the water source to which the primary side of the pump device 11 is connected is a water receiving tank has been described, but the present invention is not limited to this. The water source to which the primary side of the pump device 11 is connected may be a water pipe. That is, the water supply device 1 may be a so-called direct connection water supply device.

In the case of such a direct water supply device, the water supply device 1 is configured to be able to correct the operating frequency of the inverter 51 during the backup operation in consideration of the fluctuation of the suction pressure of the pump device 11. Specifically, as shown in FIG. 4, the water supply device 1 further includes a second pressure detector 23 provided on the primary side of the plurality of pump devices 11 in addition to the above-described configuration.

The second pressure detector 23 is configured to be able to detect the suction pressure of the pump device 11. The second pressure detector 23 is electrically connected to the control panel 22 via a signal line or the like. The second pressure detector 23 is, for example, a pressure gauge that outputs a signal corresponding to the pressure. The second pressure detector 23 converts the detected pressure into a signal and transmits the signal to the control panel 22.

The control unit 53 of such a water supply device 1 performs an estimated terminal pressure constant control during normal operation. When the control unit 53 detects the number of pulses n ₀ at the stopped flow rate by the first flow rate detector 19 during normal operation, the control unit 53 further stores the pressure P ₀ detected by the second pressure detector 23 in the storage unit 52. ..

The control unit 53 further performs the following operations during the backup operation. The control unit 53 uses the target pressure H corresponding to the flow rate, which is generally determined to perform the estimated terminal pressure constant control. During the backup operation, the control unit 53 subtracts the pressure P detected by the second pressure detector 23 from the target pressure H corresponding to the flow rate detected by the first flow rate detector 19. Further, the control unit 53 subtracts the pressure P ₀ stored by the storage unit 52 from the target pressure H. As shown in the following mathematical formula (4), the control unit 53 calculates the square root of the ratio of these calculation results as the correction coefficient α.

Then, the control unit 53, as shown in the following formula (5), a target operating frequency f _t, which is calculated by one of Equation (1) to (3), further multiplied by the correction coefficient alpha, the corrected target driving Calculate the frequency f _ct . The control unit 53 controls the operating frequency of the inverter 51 to the calculated correction target operating frequency _ftc .

According to the water supply device 1 configured in this way, even if the suction pressure of the pump device 11 fluctuates, the target operating frequency of the inverter 51 during the backup operation can be corrected according to the fluctuation amount of the suction pressure. .. That is, the water supply device 1 can control the operating frequency of the inverter 51 in consideration of the fluctuation of the suction pressure of the pump device 11 even under the installation condition in which the suction pressure of the pump device 11 fluctuates.

The present invention is not limited to the above embodiment, and can be variously modified at the implementation stage without departing from the gist thereof. In addition, each embodiment may be carried out in combination as appropriate, in which case the combined effect can be obtained. Further, the above-described embodiment includes various inventions, and various inventions can be extracted by a combination selected from a plurality of disclosed constituent requirements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the problem can be solved and the effect is obtained, the configuration in which the constituent requirements are deleted can be extracted as an invention.

1 ... Water supply device, 11 ... Pump device, 12 ... Discharge pipe, 13 ... Check valve, 14 ... On / off valve, 15 ... Connecting pipe, 16 ... Connecting pipe, 17 ... Accumulation device, 18 ... Relief pipe, 19 ... First Flow rate detector, 20 ... 1st pressure detector, 21 ... 2nd flow rate detector, 22 ... Control panel, 23 ... 2nd pressure detector, 31 ... Motor, 32 ... Pump, 32a ... Suction port, 32b ... Discharge port , 41 ... rotary shaft, 42 ... impeller, 43 ... detection unit, 51 ... inverter, 52 ... storage unit, 53 ... control unit.

The water supply device according to an embodiment of the present invention detects a pump, a plurality of pump devices having a motor for driving the pump, an inverter for driving the motor, and a flow rate on the secondary side of each of the plurality of pump devices. The plurality of first flow detectors, the first pressure detector provided on the secondary side of the plurality of pump devices, the stop flow rate Q0, the maximum operating frequency fmax of the inverter, and the operating frequency of the inverter are the same. A storage unit that stores the rated flow rate Q1 when the maximum operating frequency is fmax and the discharge pressure of the pump device is the rated set pressure P1, and the first flow rate detection during the normal operation of the pump device. The operating frequency of the inverter when the stop flow rate Q0 is detected by the pump is set as the stopped operating frequency f0 and stored in the storage unit, or the stopped operating frequency f0 stored in the storage unit is updated. When a failure of the first pressure detector is detected, the normal operation is shifted to the backup operation, and the first flow rate is used by using the stopped operation frequency f0 and the maximum operating frequency fmax stored in the storage unit. The relationship between the flow rate detected by the detector and the operating frequency of the inverter was derived, and the operating frequency was calculated and calculated as the target operating frequency ft from the derived relationship and the flow rate detected by the first flow rate detector. A control unit that controls the operating frequency of the inverter to the target operating frequency ft, a connecting pipe that joins the secondary sides of the plurality of pump devices, a connecting pipe provided in the connecting pipe, and a connecting pipe provided in the connecting pipe. The pump device is stopped when the flow rate detected by the second flow rate detector is equal to or higher than a predetermined value , and includes a pressure accumulator device and a second flow rate detector provided in the connection pipe. Is activated, and the predetermined value is a minute flow rate .

The present invention is not limited to the above embodiment, and can be variously modified at the implementation stage without departing from the gist thereof. In addition, each embodiment may be carried out in combination as appropriate, in which case the combined effect can be obtained. Further, the above-described embodiment includes various inventions, and various inventions can be extracted by a combination selected from a plurality of disclosed constituent requirements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the problem can be solved and the effect is obtained, the configuration in which the constituent requirements are deleted can be extracted as an invention.
The following is a description equivalent to the invention described in the claims of the original application of the present application.
[1] A pump and a plurality of pump devices having a motor for driving the pump, and
The inverter that drives the motor and
A plurality of first flow rate detectors for detecting the flow rate on the secondary side of each of the plurality of pump devices, and a first pressure detector provided on the secondary side of the plurality of pump devices.
The rated flow rate Q1 when the stop flow rate Q0, the maximum operating frequency fmax of the inverter, and the operating frequency of the inverter are the maximum operating frequency fmax, and the discharge pressure of the pump device is the rated set pressure P1. A memory unit that memorizes
During the normal operation of the pump device, the operating frequency of the inverter when the stop flow rate Q0 is detected by the first flow rate detector is stored in the storage unit as the stop operation frequency f0, or the storage unit. When the stopped operation frequency f0 stored in is updated and a failure of the first pressure detector is detected, the normal operation is shifted to the backup operation, and the stopped operation frequency f0 stored in the storage unit is performed. Using the maximum operating frequency fmax, the relationship between the flow rate detected by the first flow rate detector and the operating frequency of the inverter is derived, and the derived relationship and the flow rate detected by the first flow rate detector are used. A control unit that calculates the operating frequency as the target operating frequency ft and controls the operating frequency of the inverter to the calculated target operating frequency ft.
Water supply device equipped with.
[2] The first flow rate detector is an impeller type flow rate sensor that transmits a pulse signal.
The control unit receives the pulse signal from the first flow rate detector, sets the number of pulses of the pulse signal detected by the first flow rate detector at n0 at the stop flow rate Q0, and sets the number of pulses of the pulse signal at the rated flow rate Q1. 1 The number of pulses of the pulse signal detected by the flow detector is n1, and the number of pulses n detected by the first flow detector is used to set the target operating frequency ft.
ft1 = (fmax-f0) / (n1-n0) x (n-n0) + f0 or
ft2 = (fmax-f0) / (n1-n0) ^ 2 × (n-n0) ^ 2 + f0 or ft3 = (ft1 + ft2) / 2 Water supply device.
[3] A connecting pipe that joins the secondary sides of the plurality of pump devices,
The connecting pipe provided in the connecting pipe and
The accumulator provided in the connecting pipe and
The second flow rate detector provided in the connecting pipe and
With more
The water supply device according to [1] or [2], wherein the control unit starts the stopped pump device when the flow rate detected by the second flow rate detector is equal to or higher than a predetermined value.
[4] The second flow rate detector is an impeller type flow rate sensor that transmits a pulse signal.
The control unit receives the pulse signal from the second flow rate detector, and when the number of pulses detected by the second flow rate detector is 1 p / sec or more, the control unit starts the stopped pump device [3]. ] The water supply device described in.
[5] The control unit performs estimated terminal pressure constant control during the normal operation of the pump device, and when it detects a failure of the first pressure detector, shifts from the normal operation to the backup operation [1]. The water supply device described in.
[6] The primary sides of the plurality of pump devices are connected to the water pipe,
A second pressure detector provided on the primary side of the plurality of pump devices is further provided.
The storage unit further stores the pressure P0 detected by the second pressure detector at the stop flow rate Q0.
The control unit transfers the pressure obtained by subtracting the pressure P detected by the second pressure detector from the target pressure H corresponding to the flow rate detected by the first flow rate detector and the target pressure H to the storage unit. The water supply device according to [1], wherein the square root of the ratio of the stored pressure obtained by subtracting the pressure P0 is further multiplied by the target operating frequency ft.

Claims (6)

A pump and a plurality of pump devices having a motor for driving the pump,
The inverter that drives the motor and
A plurality of first flow rate detectors for detecting the flow rate on the secondary side of each of the plurality of pump devices, and
A first pressure detector provided on the secondary side of the plurality of pump devices,
Stop flow Q _0, the maximum operating frequency f _max of the _inverter, and the operating frequency of the inverter is a the maximum operating frequency f _max, and, when discharge pressure of the pump device is rated set pressure P ₁ a storage unit for storing the rated flow to Q _1,
During normal operation of the pump device, as a stop during operation frequency f ₀ to the operation frequency of the inverter when detecting the stop flow Q ₀ by the first flow rate detector, or stored in the storage unit, or the When the stopped operation frequency f ₀ stored in the storage unit is updated and a failure of the first pressure detector is detected, the normal operation is shifted to the backup operation, and the stopped operation frequency f ₀ stored in the storage unit is changed. Using the operating frequency f ₀ and the maximum operating frequency f _max , the relationship between the flow rate detected by the first flow rate detector and the operating frequency of the inverter is derived, and the derived relationship is detected by the first flow rate detector. from the flow rate and a control unit that the operation frequency is calculated as the target operating frequency f _t, for controlling the operation frequency of the inverter to the calculated the target operating frequency f _t,
Water supply device equipped with. The first flow rate detector is an impeller type flow rate sensor that transmits a pulse signal.
The control unit receives the pulse signal from the first flow rate detector, sets the number of pulses of the pulse signal detected by the first flow rate detector at the stop flow rate Q ₀ to n ₀ , and sets the rated flow rate Q ₁ sometimes the number of pulses of the pulse signal detected by the first flow rate detector and n _1, using the number of pulses n detected by the first flow rate detector, the target operating frequency f _t,
f _t1 = (f _max −f ₀ ) / (n ₁ −n ₀ ) × (n −n ₀ ) + f ₀ or
f _t2 = (f _max −f ₀ ) / (n ₁ −n ₀ ) ^ 2 × (n−n ₀ ) ^ 2 + f ₀ or
The water supply device according to claim 1, wherein the water supply device is calculated by using any of the formulas represented by f _t3 = (f _t1 + f _t2 ) / 2. A connecting pipe that joins the secondary sides of the plurality of pump devices,
The connecting pipe provided in the connecting pipe and
The accumulator provided in the connecting pipe and
The second flow rate detector provided in the connecting pipe and
With more
The water supply device according to claim 1 or 2, wherein the control unit starts the stopped pump device when the flow rate detected by the second flow rate detector is equal to or higher than a predetermined value. The second flow rate detector is an impeller type flow rate sensor that transmits a pulse signal.
A claim that the control unit receives the pulse signal from the second flow rate detector and starts the stopped pump device when the number of pulses detected by the second flow rate detector is 1 p / sec or more. The water supply device according to 3. The first aspect of claim 1, wherein the control unit performs an estimated terminal pressure constant control during the normal operation of the pump device, and when a failure of the first pressure detector is detected, shifts from the normal operation to the backup operation. Water supply device. The primary side of the plurality of pump devices is connected to the water pipe,
A second pressure detector provided on the primary side of the plurality of pump devices is further provided.
The storage unit further stores the pressure P ₀ detected by the second pressure detector at the stop flow rate Q ₀ .
The control unit transfers the pressure obtained by subtracting the pressure P detected by the second pressure detector from the target pressure H corresponding to the flow rate detected by the first flow rate detector and the target pressure H to the storage unit. water supply apparatus according to claim 1 in which the pressure of the pressure P ₀ which is stored by subtracting the square root of the ratio of further multiplying the target driving frequency f _t.