JP2012112363A - Water supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water supply device capable of stabilizing a water supply pressure when renewing a target pressure of terminal pressure constant control (or discharge pressure constant control).SOLUTION: In the water supply device including a pump connected to a water supply pipe to supply water, an inverter driving the pump at a variable speed, a pressure detection means detecting a pressure at a discharge side of the pump, a target pressure setting means for setting a target pressure at the discharge side of the pump, and a control unit controlling the inverter so that the pressure detected by the pressure detection means becomes the target pressure. When a set time has elapsed while the pressure detected by the pressure detection means reaches the target pressure, the target pressure is renewed by the target pressure setting means.

Description

  The present invention relates to a water supply apparatus.

As a background art in this technical field, there is JP 2009-47125 A (Patent Document 1). This publication states that “Necessary for pump operation control and constant terminal pressure control at one point of water supply unit requirement specifications (water quantity Q0, total head H0) in a water supply apparatus using a plurality of pumps driven by a plurality of variable speed drive means. The present invention provides a water supply apparatus using a variable speed pump suitable for automatically generating various parameters and arithmetic expressions, a plurality of variable speed pumps and water supply pipes 1 driven by variable speed drive means, and a water supply pipe 1 In a water supply apparatus comprising pressure detection means, means for setting a desired pressure target value of the water supply system, and means for variable speed operation so that the pump has a predetermined relationship according to the pressure target value, Based on the unit requirement specification data, it has means for automatically generating an arithmetic expression for constant terminal pressure control and means for storing the generated arithmetic expression. Based on data, is described a means for automatically generating a parameter required for constant end pressure control, it means for storing the generated parameters to have. "(See abstract).

JP 2009-47125 A

  Patent Document 1 describes a water supply device that performs constant terminal pressure control. However, Patent Document 1 does not disclose that the feed water pressure is stabilized so that hunting does not occur when the target pressure of terminal pressure constant control (or discharge pressure constant control) is updated.

  Therefore, the present invention provides a water supply apparatus that can stabilize the water supply pressure when the target pressure of the terminal pressure constant control (or the discharge pressure constant control) is updated.

In order to solve the above problems, for example, the configuration described in the claims is adopted.
The present application includes a plurality of means for solving the above-mentioned problems. For example, a pump connected to a water supply pipe for supplying water, an inverter for driving the pump at a variable speed, and a pressure on the discharge side of the pump. Water supply provided with pressure detection means for detecting the target pressure, target pressure setting means for setting the target pressure on the discharge side of the pump, and a control unit for controlling the inverter so that the pressure detected by the pressure detection means becomes the target pressure In the apparatus, when the set time elapses with the pressure detected by the pressure detection means reaching the target pressure, the target pressure setting means updates the target pressure.

  ADVANTAGE OF THE INVENTION According to this invention, when the target pressure of terminal pressure constant control (or discharge pressure constant control) is updated, the water supply apparatus which can stabilize water supply pressure can be provided. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

It is an operation characteristic figure which illustrated the case where three pumps are operated in parallel. It is the piping system diagram and control circuit diagram of a water supply apparatus. It is a flowchart for demonstrating the action | operation and control procedure of a water supply apparatus. It is a flowchart for demonstrating the action | operation and control procedure of a water supply apparatus. It is a flowchart for performing the calculation type | formula automatic update of the periodic target pressure of a water supply apparatus. It is a figure explaining the operation | movement which converges the target pressure of terminal pressure constant control on a resistance curve. It is a figure for demonstrating a memory map. It is a figure which shows the parameter regarding the computing equation of terminal pressure constant control. It is a figure explaining each step of the process in the key operation part 10 of the setting means CONS4, and its process. It is a figure explaining each step of the process in the key operation part 10 of the setting means CONS4, and its process. It is a flowchart which shows the setting and preservation | save procedure of the performance specific parameter of a specific model.

  Hereinafter, examples will be described with reference to the drawings.

Hereinafter, Example 1 will be described with reference to the drawings.
FIG. 1 is an operation characteristic diagram exemplifying a case where three pumps are operated in parallel. The vertical axis represents the water supply pressure head H (m), and the horizontal axis represents the amount of water used Q (m3 / min). . In the range where the amount of water used is smaller than Q2, one pump is operated, in the range exceeding this and smaller than Q3, two pumps are operated in parallel, and in the range of used water more than this, three pumps are operated in parallel. Curves A, B, C, D, E, and F have, for example, inverter frequencies fb (minimum frequency when one unit is operating), fa (maximum frequency when one unit is operating), fc (minimum frequency when operating two units), fa2 (2 units are in parallel operation at maximum frequency fa), fd (minimum frequency when 3 units are operating), and fa3 (3 units are in parallel operation at maximum frequency fa). If it changes during this time, the pump QH performance curve will change corresponding to these frequencies.

  Curve G is the resistance curve of the water supply pipe determined according to the building that is the target of water supply. When the amount of water used varies from 0 to 100%, the pressure on the discharge side of the pump (the position where the pressure sensor 8 is attached) Change the inverter frequency so that it is on the resistance curve, and increase or decrease the number of pumps. This is generally called the terminal pressure constant control method, and the resistance curve G is generated at the left end SB (generated at the intersection with the pump performance curve A at the amount of water used 0), and at the intermediate point SA (pump performance curve at the amount of water used Q2). B, C)), intermediate point SC (generated at intersections with pump performance curves D, E at water usage Q3), right end SD (generated at intersection with pump performance curves F at usage water Q4) This is a line segment, and is shown by an example of linear approximation for convenience of explanation.

  Actually, in the range where the amount of water used is less than Q2, one pump operates at variable speed, and in the range where Q3 is less than Q3, the following pump becomes variable speed operation, and the preceding machine becomes fixed speed operation of MAX. In the range of water usage, the pump that follows in the same manner is variable speed operation, and the two preceding machines are in MAX fixed speed operation. The calculation formula of the terminal pressure constant control is applied to the unit operating at the variable speed.

  FIG. 2 shows a piping system diagram and a control circuit diagram of the water supply apparatus of this embodiment. 1-1, 1-2 and 1-3 are suction pipes, 2-1 to 2-6 are gate valves, 3-1, 3-2 and 3-3 are motors 4-1, 4-2 and 4- 3, pumps for supplying water on the suction side to the demand side through the suction pipes 1-1, 1-2, 1-3, 5-1, 5-2, 5-3 are check valves, 6 Is a water supply pipe, 7 is a pressure tank, 8 is a pressure sensor provided in the water supply pipe 6 for detecting the pressure therein and generating a pressure signal in response thereto. PW is a power source, and ELB1, ELB2, and ELB3 are earth leakage breakers of Unit 1, Unit 2, and Unit 3, respectively, and perform leakage protection for the subsequent systems. INV1, INV2, and INV3 are inverters that drive the motors 4-1, 4-2, and 4-3, respectively, and have predetermined frequencies and voltages according to speed command signals f1, f2, and f3 from the control unit CU described later. give. Further, f10, f20, and f30 are returned to the control unit CU as the current frequency of the inverter with respect to these designated frequencies. Furthermore, consoles CONS1, CONS2, and CONS3 that display current, frequency, operation, and failure status or that include key input switches and the like are provided. Also, the operation is started when the operation command signals RUN1, RUN2, and RUN3 are turned on, and stopped when the operation command signals are turned off. R and S are control power supplies, TR is a transformer, and its secondary side is connected to the power supply terminal of the control unit CU. The control unit CU includes a console CONS4 that displays operation and failure states or includes a key input switch and the like. The current frequency f10, f20, f30 of the inverter and the signal SW of the pressure sensor 8 are input, the operation switch SS is provided with an input terminal, the speed command signals f1, f2, f3 to the inverter, and the operation signals RUN1, RUN2 , And an output terminal for outputting RUN3 to the relay. For simplicity, the current frequencies f10, f20, and f30 of the inverter may be replaced with the command frequencies f1, f2, and f3. Further, the above-described control unit CU includes a microcomputer CPU and a storage unit M, and can input a plurality of set value (parameter) data and a set value (command) of CONS4.

An example of a method for obtaining a set value (parameter), a variable value that is a current frequency, and an arithmetic expression in pressure control in the water supply apparatus of the present embodiment will be described. An arithmetic expression for controlling the constant terminal pressure will be described with reference to FIG. That is, when the function of the curve G is between 0 and Q2, the target pressure head (on the resistance curve) SV can be expressed by the following formula from fx that is the current frequency of the pump. Equation (1) is a case of linear approximation, and Equation (2) is a case of quadratic curve approximation.
SV = (SA-SB) / (fa-fb) * (fx-fb) + SB ------------- (1)
SV = (SA−SB) / (fa−fb) ² × (fx−fb) ² + SB −−−−−−−−−−− (2)
Further, the function of the curve G can be expressed by the following equation from the amount fx, which is the current frequency of the pump, of the target pressure head (on the resistance curve) SV between the water amounts Q2 to Q3. Equation (3) is a case of linear approximation, and Equation (4) is a case of quadratic curve approximation.
SV = (SC-SA) / (fa-fc) * (fx-fc) + SB ------------- (3)
SV = (SC-SA) / (fa-fc) ² × (fx-fc) ² + SB --------- (4)
Further, the function of the curve G can be expressed by the following equation from the amount fx that is the current frequency of the pump, with the target pressure head (on the resistance curve) SV between the water amounts Q3 to Q4. Equation (5) is a case of linear approximation, and Equation (6) is a case of quadratic curve approximation.
SV = (SD-SC) / (fa-fd) * (fx-fd) + SC ------------- (5)
SV = (SD−SC) / (fa−fd) ² × (fx−fd) ² + SC ---------- (6)
Here, the following set values (parameters) are known (constants) and are used as generation values of the above arithmetic expressions or determination values for pump operation control. SB is a starting pressure head of a pump that is operated first from a state where the pump is completely stopped, and is a lower limit target pressure head when the water amount is zero. However, the starting pressure head and the lower limit target pressure head need not be the same. SB is obtained as (actual head + required end pressure head).
SC is a stop pressure head that stops at the end of the pump (stops by increasing the frequency to fst), and is an upper limit target pressure head when the amount of water is Q3.
SA is an intermediate target pressure head (m) at the time of water quantity Q2.
SB is a pump cutoff pressure head (when the frequency is Nm) (m).
Hton is the second parallel introduction pressure.
Htoff is a second parallel release pressure head.
Hton ′ is a third parallel introduction pressure head.
Htoff ′ is a third parallel release pressure head.
fa is the maximum pump frequency when one unit is operating.
fb is the lowest pump frequency when operating one unit.
fa2 is the pump maximum frequency when operating two units in parallel.
fc is the pump minimum frequency during the second unit operation when the amount of water used is Q2.
fa × 3 is the maximum pump frequency when three units are operating in parallel.
fd is the lowest pump frequency during operation of the third unit at the amount of water used Q3.
fa and SS are set values (parameters) for specifying the pump performance, which are the maximum frequency and the deadline pressure head at this time, and these are fixed values.

  fst is a frequency when the first pump is stopped. In FIG. 1, when the amount of water used is small and the pump may be stopped (the amount of water used is Q1), the inverter frequency is increased from fb to fst and stopped. This means filling the pressure tank with water. Further, fx is a current frequency and is a variable. By substituting this value into the equations (1), (3), (5) or (2), (4), (6), a target pressure head at the current frequency is generated. If the timing for updating the calculation formula for the target pressure is the time when the target pressure and the feed water pressure coincide with each other, hunting may occur when the amount of water used varies, and the feed water pressure may vary.

  As shown in the above-described target pressure calculation formulas (1) to (6), in order to generate this, it is necessary that the set value (parameter) is 5 quantities and the variable value is 1 quantity. It may be said that this is a problem, and it is difficult for the contractor to understand and is troublesome. Many types of such water supply systems are in series, and if setting values (parameters) are set for each model, the control system cannot be shared and shared, and adjustment and handling at the time of shipment from the factory are not possible. There is a troublesome problem.

  3 and 4 are flow charts for explaining the operation and control procedure of this embodiment. This flowchart is preinstalled in the above-described memory M of the CU as a program. FIG. 7 is a memory map. In FIG. 3, an interrupt prohibition process D1 is executed in 300 steps in preparation for the initial process in the next 301 steps, for example. In the initial process, various processes such as register, interrupt vector, memory, and stack pointer are executed to prepare for startup. In step 302, SA, which is a parameter necessary for setting (changing) the target pressure shown in FIG. 7, is stored in the EEPROM memory M0, SC is set in M1, SD is set in M2, SD is set in M3, and Hoff and SA are set in the same manner. The difference x is set to M10, the difference Y between SA and Hton is set to M11, the maximum frequency fa for specifying the performance of the model A is set to M13, the pressure head SS is set to M14, and the maximum frequency fa for specifying the performance of the model B is set to M15. The deadline pressure head SS is stored in M16, the highest frequency fa that specifies the performance of the model C is stored in M17, the deadline pressure head SS is stored in M18, and the highest frequency fa that specifies the performance of the model D is stored in M19. In addition, the model selection address pointer is stored in M30 and M31.

  For example, for model A, M14 is written and stored in M30 and M13 is stored in M31. The lower limit pressure head SB, which is a data parameter, is set to M100, and similarly, the first start pressure head PON is set to M101 (PON = SB or not), and the first stop pressure head Poff is set to M102 (POff = SA may or may not be), the second start pressure head Hton is M103, the second stop pressure head Htoff is M104, the third start pressure head Hton 'is M105, the third stop pressure The head Htoff 'is M106, the maximum frequency fa that specifies the performance of the model is M107, the deadline pressure head SS is M108, fb is M109, fc is M110, fd is M111, and the current speed fx is M112. Hereinafter, the storage locations of the command frequency data f1, f2, f3, the arrival frequency data f10, f11, f12, etc. are stored in the memory RA. It is defined as reserved and variable.

  Here, the process of writing data to the memory EEPROM can be performed in advance by another process. In the next 303 steps, the current frequency fx is set to 0 and the initial target pressure head is set to SV = SB by using the arithmetic expression for the terminal pressure constant control, that is, the expressions (1) to (6) described in paragraph 0016. Here, for simplicity, linear approximation formulas (1), (3), and (5) are used, and quadratic function formulas (2), (4), and (6) are used for accurate implementation.

  In step 304, the initial processing, parameter setting processing, and arithmetic expression control parameter initialization processing are completed, and therefore interrupt permission processing EI is executed. Subsequently, in step 305, timer processing Δt is executed and an interrupt is waited for. Naturally, an interrupt occurs, and the processing after step 400 in FIG. 4 is executed.

  In the INT0 interrupt processing after 400 steps, as shown in FIG. 4, it is determined in step 401 whether the key switch 10 in FIG. 2 has been pressed. As a result of the determination, if not pressed, the process proceeds to step 402, for example, the pressure determined by the initial value is displayed, and in step 409, the process returns from the interrupt process to the pre-interrupt process RET0. If the key switch 10 is pressed in the determination result in step 401, the process proceeds to step 403, and it is determined whether the pressed key switch 10 is a parameter change key. If it is a parameter change key, the process proceeds to step 405, and in the subsequent processing, the parameter setting (indicating that it can be changed) process and the storage process to the memory are executed in the same manner as described in step 302. In this way, parameter settings can be changed even during operation.

  In the INT1 interrupt processing after 410 steps, as shown in FIG. 4, failure check and monitoring are performed at 411 steps. In step 412, the pressure sensor signal is detected, and the data of the analog register AN 0 is stored in the memory M 110. In step 413, the current frequency of the inverter is detected and stored in the memories M107 and 108. In step 414, the process returns from the interrupt process to the process before the interrupt.

  In this way, in step 306 in FIG. 3, the determination is made until the value detected by the pressure sensor becomes equal to or less than the starting pressure head PON (described as PON = SB in this embodiment). If it is less than or equal to Pon, the process proceeds to step 307, the first pump is commanded to start, and in step 308, the target pressure head is set as the initial value and H0 = SB. This is the value processed in step 303 and stored in the register. Next, in step 309, the target pressure head H0 (H0 = SB) is compared with the pressure data H detected by the pressure sensor. As a result, if H0 + 2m <H, it indicates that the feed water pressure is higher than the target pressure head H0, and the deceleration process after 310 steps is executed.

  If H0-2m> H in step 309, it indicates that the feed water pressure is lower than the target pressure head H0, and the speed increasing process after step 316 is executed. If H0 + 2m = H in step 309, it indicates that the target pressure head H0 is equal to the feed water pressure, and the process proceeds to step 311 where it is determined whether a predetermined time has elapsed. If it has elapsed, the target pressure head update process is executed by the calculation formula in 312 steps. In this case, as described above, the arithmetic expression is automatically generated using the data stored in the memory according to the arithmetic expression (1) or (2). Then, the target inverter is updated by substituting the current inverter frequency into fx in this arithmetic expression, and jumps to step 309. You may leave the process here. Thereafter, the processing is continued by comparing with the updated target pressure head and the value detected by the pressure sensor, and the subsequent processing is continued.

  Returning to the explanation, after executing 310 steps and 313 steps of the deceleration process, it is determined whether the command frequency from the CU to the inverter matches the inverter arrival frequency (answer back from the inverter to the CU). If they match, the target pressure is updated in the same manner as described above in step 314. In step 315, although not shown in FIG. 1, it is determined whether the flow switch is operating. The flow switch is a flow rate switch. When the flow rate of the flow switch is, for example, 10 l (liter) / min or less and is turned on, and 15 l / min or more, the flow switch is turned on. A pump stop command is issued here. Then, in step 317, an alternate switching process (rotary operation process is performed when there are three or more pumps) is executed, and the process jumps to step 305. The alternate switching process is a process of switching the pointer so that, for example, if the pump that is currently operating is No. 1, the next pump to be operated is No. 2. Similarly, the rotary operation process is a process of switching the pointer so that the operation order becomes No. 1 → No. 2 → No. 3 → No.

  After executing 318 steps and 319 steps of the speed increasing process, it is determined whether the command frequency from the CU to the inverter matches the inverter arrival frequency (answer back from the inverter to the CU). If they match, the target pressure is updated in 320 steps in the same manner as described above. In step 321, it is determined whether the current frequency has reached the maximum frequency fmax (here, fmax = fa). When the maximum frequency fmax is reached, no further capability can be obtained, so the parallel introduction pressure head Hton stored in the memory is read and compared with the pressure data detected by the pressure sensor in the next 322 step. If the pressure data detected by the pressure sensor is lower than the pressure head Hton, the process proceeds to step 324, where a second parallel operator command is transmitted. Since it is clear from the above description, the description of the process of increasing or decreasing the number of third or more pumps will be omitted.

  As described above, in this embodiment, the target pressure calculation formula is automatically updated in steps 312, 314, and 320 in FIG. 3, but this calculation formula automatic update is performed by processing any one of them independently. Others may be masked, may be processed in combination, or all three may be processed. Further, the periodic automatic calculation of the target pressure as shown in FIG. 5 may be executed in combination with the above-described steps of FIG. As a result, when the target pressure calculation formula is automatically updated, it is possible to prevent hunting from occurring and pressure fluctuation from occurring.

  In FIG. 1, SA is the first pressure set value (upper limit side), SB is the second pressure set value (lower limit side), the first frequency set value for specifying the pump performance is fa, and SS is the first pressure set value. Fb, a second frequency set value that satisfies the third pressure set value at the pump cutoff operation when operating at the frequency set value fa of 1, and the second pressure set value (lower limit side) SB at the pump cutoff operation. When the first variable which is the speed command signal commanded by the speed command means is fx, the current speed command signal is fDATA, the feed water pressure detected by the pressure sensor is SDATA, and the target value of the terminal pressure constant control is SV. The calculation formula for the constant terminal pressure control may be given by the above-described formula (1) obtained by linear approximation, and the following procedure may be added to steps 303, 312, 314, and 320 in FIG.

Step 1 Process in 303 steps
fb = fa * √ (SB / SS)
Step 2 Process in step 303
SV = (SA−SB) * (fx−fb) / (fa−fb) + SB (1)
Step 3 Process in 311, 314, 320 steps
When the target pressure is reached, a certain time elapses, or when the command speed stops changing, or when the frequency reaches, or a combination thereof, or the current speed is periodically set in the variable fx of the equation (1). The command signal fDATA is substituted. (SB and fb obtained in step 1 and step 2 are substituted into equation (1).) In the above, linear approximation is shown as an example, but in the case of quadratic curve approximation, the above step 2 is described above. As shown in Equation (2), the following equation is used.
S0 = (SA−SB) * (fx−fb) ² / (fa−fb) ² + SB (2)
FIG. 5 can be executed by, for example, 100 msec timer interruption processing. In the figure, in steps 501 to 504, changes in the current water supply pressure and the water supply pressure in the previous time are detected in a predetermined time, and in steps 505 to 508, changes in the command frequency to the inverter and the previous command frequency are determined in advance. Detected by time, detects whether the command frequency to the inverter and the inverter arrival frequency match at steps 509 to 510 at a predetermined time, and if these are true, automatically calculates the target pressure calculation formula at step 511 It is a thing. Since the update method procedure is clear as described above, a description thereof will be omitted. In this way, it is possible to prevent the amount of water used from fluctuating and causing inverter frequency fluctuations, target pressure hunting, and pressure fluctuations when the target pressure is updated.

  Next, how the target pressure of the terminal pressure constant control described above converges on the resistance curve will be described with reference to FIG. In order to make the explanation simple and easy to understand, the explanation will be made excluding the dead zone 2m of the target pressure. In FIG. 6, it is assumed that the operation is performed at the intersection Oi between the resistance curve E and the pump performance curve at the inverter frequency Ni and the target pressure H0i. Here, the target pressure H0i is obtained as a result of substituting the frequency Ni for the current frequency fx, which is a variable, in the aforementioned arithmetic expressions (1) to (6). Consider a case where the amount of water used increases from Qi to Qi1 in this state. Naturally, the feed water pressure decreases and the operating point becomes O1.

  The pressure sensor detects this reduced pressure, compares it with the target pressure H0i, and executes a process of increasing the inverter frequency to Ni1. As a result, the operating point moves to the point O2, but is not equal to the target pressure H0i, so the above-described speed increasing process is executed until they become equal. As a result, the inverter frequency is Ni2, the operating point is O3, and the target pressure H0i matches the feed water pressure detected by the pressure sensor. Here, as described above, the update condition of the target pressure is that when the target pressure is reached and a certain time elapses, or when the command speed stops changing, or when the frequency reaches, or a combination thereof, Update. That is, the target pressure H01 is obtained by substituting the inverter frequency Ni2 for the variable fx of the arithmetic expression. The virtual operating point at this time is O4. However, the amount of water used is Qi1, the water supply pressure is H0i, and the actual operating point is O3. The water supply pressure is still lower than the target pressure H01. Although not shown, the target pressure converges on the resistance curve E as a result of repeating the above processing procedure.

  Although the above description has shown the case where the amount of water used increases, it can be similarly estimated when the amount of water used decreases. That is, the feed water pressure once rises and the target pressure and the feed water pressure converge on the resistance curve. By the way, if the target pressure setting update condition described above is not satisfied, the discharge pressure is constantly controlled by the previous target pressure, and the predetermined pressure on the resistance curve cannot be set as the target pressure, resulting in a pressure drop or a pressure high. It is expected to happen. Therefore, as a countermeasure against this, before executing the acceleration process or the deceleration process, the time when the target pressure is not updated and the increase / decrease of the speed change are measured, and the target pressure is updated when the predetermined time elapses. Then, the inverter frequency to be substituted into the arithmetic expression at the time of updating is the average of the increase / decrease of the measured speed change, and this is the value added to the frequency before updating. Specifically, it may be executed by the 318 step acceleration process, the 310 step deceleration process, and the 312 step target pressure update process of FIG. 3 in the flowchart.

  Note that when the target pressure is not updated within the second set time longer than the set time, and the third set time elapses without the pressure detected by the pressure detection means changing, the target The pressure setting means may update the target pressure.

  Example 2 will be described with reference to the drawings. In this embodiment, required set values and variable values required for the water supply device are set such that when the number of pumps is one, the pressure set value is three, the frequency set value is two, the frequency variable is one, and the number of pumps is When there are 2 units, the pressure setting value is 4 amounts, the frequency setting value is 3 amounts, the frequency variable value is 1 amount, and when 3 pumps are operated, the pressure setting value is 5 amounts, the frequency setting value is 4 amounts, and the frequency variable 1 quantity,. . . . When n pumps are operated, the pressure set value is defined as 2 + n, the frequency set value is defined as 1 + n, and the frequency variable value is defined as 1 according to the number of pumps operated.

  For example, when the number of pumps operated is one, the required pressure setting values are SB, SA, SS shown in FIG. 1, the frequency setting values are fa, fb, and the frequency variable value is fx as in the first embodiment. is there. As shown in FIG. 8, the total number of parameters, the number of parameters necessary for generating the constant pressure control formula, the number of parameters required for the pump operation stop command, and the parameters necessary for changing the target pressure of the feed water pressure. The software program is created by organizing and storing the number of parameters that can be hidden and the number of parameters that can be hidden.

  In this embodiment, among the setting parameters shown in FIG. 1, the SA, SC, SD, and H0 stored in the memories M0, M1, M2, and M3 in FIG. It is intended to be displayed. These setting parameters must be set by the equipment supplier when installing the water supply device. By displaying these setting parameters and making others hidden, only the parameters that need to be set are displayed. Since it can be confirmed, the equipment supplier can easily set parameters.

  FIG. 9 and FIG. 10 show each step of the process in the key operation unit 10 of the setting means CONS4 and how the result of the process is displayed on the display unit. This process is shown in steps 400 to 409 in FIG. If the key switch is not pressed in step 401, as shown in step 402, only the pressure set in initialization, that is, the above-described SA, SC, SD, and H0 are displayed, and other parameters are not displayed. . Therefore, the equipment contractor can set parameters that require initial setting without making mistakes with other parameters.

  Here, if the up and down keys are both pressed in the operation of 800 steps in FIG. 9, the key switch of 401 steps in FIG. 4 is pressed, resulting in 403 steps. Then, as a result of the determination at step 403 in FIG. 4, the process proceeds to steps 405 to 408, and the processing after step 801 shown in FIG. 9 is executed. That is, in the present embodiment, only the parameters that need to be initially set are displayed first, but other hidden parameters whose settings can be changed can be changed.

  In step 801, the parameter with the smallest number (for example, P00) is displayed, and the display method is, for example, the parameter number at the left end, and the right side A and B are data. In order to select a parameter to be set or changed, an up key or a down key in steps 802 and 803 is pressed and appropriately selected. If the parameter P10 shown in step 804 is the target parameter, the enter key is pressed in step 805. A cursor (for example, a thick underline) is displayed in the data A part. This can be set or changed. That is, the current data is overwritten and set or changed. Moving the cursor to the right is the up key (see step 807), and moving the cursor to the down key (see step 808). When the enter key is pressed again, the data is confirmed and the cursor disappears. When the enter key is pressed while parameters (number and data) are displayed, the cursor is displayed and can be set. When the enter key is pressed again, the cursor disappears and the display is only displayed.

  When the up key and the down key are both pressed for a long time, the mode changes from the parameter setting mode to the display mode. When the setting change of the hidden parameter is completed, it can be set to display only the pressure whose original initial display is determined in this way. If the up key is continuously pressed, for example, parameter P19 can be seen (displayed), but no more can be seen (see step 811). In this display mode, only the pressure for which the original initial display is determined is displayed. However, the hidden parameter is displayed by pressing and holding the up key, down key, and enter key in step 812. Can be seen.

Of the hidden parameters, the first parameter to be displayed is, for example, the parameter P20. Hereinafter, the parameters that can be seen as described above are set or changed. (Steps 813 to 815) Then, when the three keys, the up key, the down key, and the enter key are pressed again, the parameter that was visible becomes the hidden parameter again (see step 816). Here, the parameters P00, P01, P02,. . . . Are memories M0, M1, M2. . . It corresponds to. (See Figure 7)
Further, in this embodiment, a storage unit for storing at least the frequency set value fa and the pressure set value SS shown in FIG. 1 for specifying the performance of the variable speed pump is provided for a plurality of models, and the frequency set value fa and the pressure set value are provided. An address pointer for reading the frequency setting value fa and the pressure setting value SS of a predetermined model is set (written) in the storage unit that stores the SS. As shown in FIG. 7, the fa and SS data for specifying the performances of the models A to E are set in the memories M13 to M22, and the model selection address pointer is set in the memories M30 and M31. The data fa and SS that specify the pump performance read by the address pointer are stored in the memories M107 and M108.

  Specific processing will be described with reference to FIG. Fig. 11 is a flowchart showing the procedure for setting and saving the performance specification parameters for a specific model. Only a specific model is selected from many models in the entire series (selection is an artificial means), and the performance is specified. It is the flowchart explaining the process which reads the setting value (parameter) to perform and preserve | saves to memory (RAM). This flowchart is executed in the process in step 405 of FIG.

  In step 100 of FIG. 11, the address pointers set (saved) in the memories M30 and M31 (for example, M13 and M14 for the model A and M15 and M16 for the model B) are loaded. In step 101, memory data fa (the highest frequency of the model) and SS (the deadline pressure head when operating at the highest frequency fa) indicated by the address pointer are read, and in step 102, these are stored in M107 and M108 of the memory RAM. Keep it. The stored fa and SS data are used to generate a target pressure calculation formula in steps 302, 312, 314, 320, and 323 shown in FIG. In this way, the address pointer that designates the memory in which the performance specification parameter of the pump is set according to the desired model at the time of shipment from the factory is set in advance, so it is necessary to change the software each time. The software can be shared and shared for all models in the entire series. For this reason, it does not take time and trouble, and it is not necessary to increase the number of software and management is easy. Of course, it is obvious that the setting can be changed at the installation site.

  As described above, in the present embodiment, the upper limit side first pressure set value and the lower limit side second pressure set value set by the setting means, the first frequency set value for specifying the performance of the variable speed pump, and this A third pressure set value at the time of pump cutoff operation when operating at the first frequency set value, a second frequency set value that satisfies the lower limit side second pressure set value at the pump cutoff operation, and the speed command means The speed command signal is determined based on the first variable, and the second frequency set value is determined based on the second pressure set value, the third pump cutoff pressure set value, and the first frequency set value. And a storage unit for storing values, and automatically generating an arithmetic expression for constant terminal pressure control based on these set values, and the plurality of pumps are operated at a variable speed in accordance with the arithmetic expression for constant terminal pressure control generated automatically. Variable speed control means In the water device, the setting other than the first pressure setting value and the fourth constant setting value is set as a hidden setting value or a hidden variable, and is visualized and set only when a specific process of the setting unit is performed. It was possible.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. In addition, a part of the configuration of a certain embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of a certain embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Each of the above-described configurations, functions, and the like may be realized by software by interpreting and executing a program that realizes each function by the processor. Information such as programs, tables, and files for realizing each function can be stored in a recording device such as a memory, a hard disk, an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.

  Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

  3-1, 3-2, 3-3 ... pump, 4-1, 4-2, 4-3 ... motor, 6 ... water supply pipe, 8 ... pressure sensor, INV1 / INV2 / INV3 ... inverter, CU ... control device .

Claims (9)

A pump connected to a water supply pipe for supplying water;
An inverter for driving the pump at a variable speed;
Pressure detecting means for detecting the pressure on the discharge side of the pump;
Target pressure setting means for setting a target pressure on the discharge side of the pump;
In a water supply apparatus comprising a control unit that controls the inverter so that the pressure detected by the pressure detection means becomes the target pressure,
The water supply apparatus according to claim 1, wherein the target pressure setting means updates the target pressure when a set time elapses in a state where the pressure detected by the pressure detection means reaches the target pressure. A pump connected to a water supply pipe for supplying water;
An inverter for driving the pump at a variable speed;
Pressure detecting means for detecting the pressure on the discharge side of the pump;
Target pressure setting means for setting a target pressure on the discharge side of the pump;
In a water supply apparatus comprising a control unit that controls the inverter so that the pressure detected by the pressure detection means becomes the target pressure,
When the first set time has elapsed with the speed command value sent from the inverter to the pump unchanged, or when the rotation speed of the pump has reached the speed command value, the second set time has elapsed. In this case, the target pressure setting means updates the target pressure. In the water supply apparatus of Claim 1,
When the first set time has elapsed with the speed command value sent from the inverter to the pump unchanged, or when the rotation speed of the pump has reached the speed command value, the second set time has elapsed. In this case, the target pressure setting means updates the target pressure. In the water supply apparatus in any one of Claims 1-3,
The target pressure setting means sets the target pressure from a piping resistance curve determined according to a water supply target. In the water supply apparatus in any one of Claims 1-3,
The target pressure setting means is configured such that the upper limit value of the rotation speed of the pump is fa, the lower limit value of the rotation speed of the pump is fb, and the intersection of the QH curve and the piping resistance curve when the rotation speed of the pump is fa. When the pressure obtained is SA, the pressure obtained from the intersection of the QH performance curve and the pipe resistance curve when the rotational speed of the pump is fb is SB, and the speed command value sent from the inverter to the pump is fx. In addition, the target pressure SV is obtained from the following formula (1) and set.
SV = (SA−SB) * (fx−fb) / (fa−fb) + SB (1)   2. The water supply device according to claim 1, wherein the target pressure setting means updates the target pressure when the target pressure is not updated within a second set time longer than the set time. A water supply device.   The water supply device according to claim 2, wherein the target pressure is updated when the target pressure is not updated within a third set time longer than either the first set time or the second set time. A water supply apparatus, wherein the pressure setting means updates the target pressure.   2. The water supply device according to claim 1, wherein the target pressure is not updated within a second set time longer than the set time, and the pressure detected by the pressure detecting means is not changed. When the set time of 3 has passed, the target pressure setting means updates the target pressure.   3. The water supply device according to claim 2, wherein the target pressure is not updated within a third set time that is longer than either the first set time or the second set time. The water supply apparatus according to claim 1, wherein the target pressure setting means updates the target pressure when a fourth set time elapses in a state where the pressure detected by the detection means does not change.

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