JPS59188096A - Supplying device using variable-speed pump - Google Patents

Abstract

PURPOSE:To aim at the promotion of reduction in a pressure variation in time of increase or decrease in pump units available, by adopting a microcomputer into a device and thereby performing its digital control. CONSTITUTION:The desired pressure prestored in a microcomputer mucon is compared with the measured pressure inside a feed water pipe 9, while an operating speed in a variable speed pump is altered so as to cause the measured pressure to accord with the desired pressure and thereby increase or decrease in plural units of constant-speed pumps takes pace. Simultaneously with this adjustment, a signal out of a pressure sensor 10 is inputted into the microcomputer mucon, performing an operation process by the program required and sending a speed change command to a variable-speed controller INV. And, a digital signal being outputted from an I/O port OutA of the microcomputer mucon is converted into an analog signal with a D/A converter F2 and outputted to the controller INV. The increase or decrease of pumps is accurately carried out with a pump increase or decrease command device CTL by the variable-speed pump operated by output from the I/O port OutB and an interface G between solenoid contactors M1 and M2 of plural units of pumps.

Description

Detailed Description of the Invention Field of Application of the Invention The present invention relates to an operation and control device for a pump device driven in a variable speed mode. [Background of the invention] The invention discloses an operation control device suitable for minimizing pressure fluctuations during whitening and calendaring] Conventionally, a variable speed mode has been used to control the water supply pipe (and pressure sensor) of a pump device driven by a variable speed mode. By setting the discharge a:','L thousand force and constantly comparing both pressures so that the discharge pressure is maintained at the target discharge pressure, a control signal of a magnitude corresponding to the deviation is generated. There is a method in which the whitened pump is taken out, whitened based on this, the amount of water used is reduced by half, and the whitened pump is mounted on a stand.

This method will be explained below using FIGS. 1 to 4.

FIG. 1 is a block diagram of the pump device, in which 1 is a water tank, 2-1. '
22 are suction pipes, 31. '32゜82.81 is the gate valve, ai, A2 are the No. 1 pump and No. 2 pump, respectively, 6+, '62 are the 1 that drives the No. 1 pump A1, respectively.
The No. 2 mode that drives the No. 2 model and the No. 2 pump A2, 71.72 are the reverse 1st valve, 9 is the water supply pipe, 10
is a pressure sensor installed in the water supply pipe 9. This pressure sensor 10 detects the pressure of fluid flowing through the water supply pipe,
In response to this, six currents of drowsiness IP (peep current or voltage) are emitted. Figure 2 shows the pump 41°A2 of the pumping device.
This is a diagram showing the operating characteristics when operating at 7# speed or at constant speed.
The water quantity Q is shown on the two axes, and the pressure H is shown on the vertical axis. Curve e shows the Q-H performance when either pump 41 or 42 is operating at maximum speed + 100%) N positive The Q, -H performance for the case is shown. In addition, curve a indicates that the variable speed pump (41 or 42) operates at the maximum speed Nmax,
It shows the combined Q-H performance when operating in parallel with the constant speed pump (A2 or 41), and similarly, curve d shows the case where the variable speed pump is operating at the minimum speed Nm1n and is operating in parallel with the constant speed pump. The synthesized Q-H performance is shown below. The operating speed of the variable speed pump is continuously variable, but for convenience, the pump's Q at any intermediate stage N, 1N2,
-H performance is curved, c, L g.

FIG. 3 is a block diagram 1 showing the signal flow of the control device, in which the error amplifier OF is used instead of the proportional integrator P.

It consists of a target pressure setting volume Vr, a proportional circuit P, an integral circuit, and an addition circuit A. The engineering NV is a variable speed control device in a variable speed mode, and in this example, a variable frequency inverter device is used, but other systems such as primary voltage control are also applicable. Further, OH8 is a switching control device that performs operation order switching, whitening, and mounting table commands, and CTL is a proportional integrator PID that controls target pressure setting volume Vr and pressure sensor 10.
The deviation Ks (J) - Fi, ) due to the signal from ), and also controls the switching control device C1H3 to change the operation order and command the pump to increase or decrease.

In Figures 1 to 3, for convenience, variable pumps are grouped together, and when the amount of water used is Q and H, the speed is N.
It is assumed that mi+ is operating on a Q-H curve.

In this state, when the amount of water used increases from Q, H to QEK, the operating speed increases from N# to N, N2, etc. while keeping the discharge pressure Ho constant. The speed increases to Nrrax, the pump Q, -He line changes from h to g, f, e, and the operating point moves from H, 6 to G, F, E, points.

Furthermore, when the amount of water used increases from Q, e to Qd, the idle pumps start, running in parallel, and the operating speed decreases to N.
From max to N miq, the pump Q-Hgj3 line changes to e7) and d, the operating point moves from E to D, and below, depending on the amount of water used, while keeping the discharge pressure constant,
Continue variable speed operation, pump whitening, and platform operation.

However, in the above prior art, when the variable speed pump reaches the maximum speed and the constant speed pump or the variable speed pump is whitened, or when the variable speed pump reaches the maximum speed and the constant speed pump or the variable speed pump When the pumps are mounted in parallel operation, extremely large pressure fluctuations occur, which has an adverse effect on the equipment used. This pressure fluctuation will be explained in detail with reference to FIG. Figure 4 shows the results obtained by the inventors by measuring the stability of the operating speed before and after the time when the above-mentioned pressure fluctuation occurs, and the state of pressure change in the water supply pipe.The horizontal axis is time t, and the vertical axis is the operating speed. and the pressure inside the water supply pipe is increased.

From the same figure, the following can be determined. That is, when the amount of water used increases from Q, e to Q4, the operating speed of the variable speed pump decreases from the maximum speed N max, and the constant speed pump starts further, so the amount of water used Q, (l On the other hand, at time 1, the Q-H performance curve of the pump is a, so the supply amount greatly exceeds the water supply, the pressure in the water supply pipe fluctuates, and the proportional integrator PID described above It works to update the operating speed from the high speed Nmx to the lowest speed Nm, but due to the relationship between the integration time and gain from P, a control delay of △t actually occurs, which is extremely larger than the target pressure. Pressure fluctuation IHmaxon, or)
(m(+21) is generated.Also, the amount of water used changes from Qd to Q,
When the operating speed of the variable speed pump is reduced to e, the operating speed of the variable speed pump increases from the state where it has reached the minimum speed Nm, and the constant speed pump stops at the same time. is h, the amount of water supplied is smaller than the amount of water used, the pressure inside the water supply pipe fluctuates, and the proportional integrator P'■D sets the operating speed of the variable speed pump to the minimum speed Nmm.
It works to update the maximum speed to Nmax, but in reality, the control delay of △t2 is overwhelming, and the pressure fluctuation Hwinoff, Hmaxoff is much larger than the target pressure.
This results in the following.

"Object of the invention" The object of the invention is to perform variable speed operation, whitening, and mounting plate connection using a plurality of variable speed pumps or constant speed pumps,
An object of the present invention is to provide a pump device that continuously maintains the discharge pressure of the pump at a constant level, and is capable of suppressing pressure fluctuations to a small level when introducing parallel operation of a plurality of pumps or when parallel operation is canceled. .

[Summary of the Invention] In the conventional pump device of this type, extremely large pressure fluctuations occurred due to the control delay from the proportional integrator P, as explained in the prior art. This is because the amount of water supplied by the pump device suddenly becomes excessive or insufficient with respect to the amount of water used, causing a change in the flow velocity in the water supply pipe. Therefore, when introducing parallel operation and canceling parallel operation, the amount of water supplied relative to the amount of water used is suddenly increased, and the other pumps are increased in volume, and the operating speed of the variable speed pump is reduced from the maximum speed to the minimum speed, and when parallel operation is canceled, the operating speed of the variable speed pump is increased. It was discovered that if the other white pumps were stopped and the operating speed of the variable speed pump was increased from the lowest speed to the highest speed, pressure fluctuations would not occur.

[Embodiments of the Invention] Hereinafter, embodiments of the present invention will be described in Section 1. Fifth. 6th. 7th, 8th
This will be explained step by step. FIG. 5 shows a control circuit of a control device according to an embodiment of the present invention, in which MOB is a breaker for the main circuit;
MCo-MC4 is a magnetic contactor coil, MOoa-MC
4a is the contact point, and NV is a variable frequency inverter device for changing the operating speed of the variable speed mode (in this embodiment, an inverter device is used, but the primary snow 11: control, Swirling joints and other speed change control 'A fabrics may also be used.) TH, TH2 are model M
1゜M2 thermal relay for overload prevention, μCon is a central processing unit CPU (hereinafter abbreviated as CPU),
The microcomputer, Fl, which is made up of the memory M-, e-pcs terminal E1 capo-) engineering NA, output boat 0UTA, 0UTB, converts the analog signal sent from the pressure sensor company into a digital signal, A/D for reading the microcomputer μcon K
Conversion 2sho, F2 is a D/A converter that converts the speed command signal (digital signal) sent from the microcomputer μcon from a digital signal to an analog signal, and sends it to the variable frequency inverter NV. It shows an interface connected to the output port ()OUTA of the computer μcan, and transistors Tr,) to Tr4.
．． Consists of relay 10-X4 + resistor R6-R4゜,
For example, from the above-mentioned output port) OUTA, the signal O section 9, 6.
When outputted, transistor Tr4 passes through four times, relay X4 is energized, and electromagnetic contactor Me4 is energized. Further, X is an operation circuit section consisting of a transformer T1, a source unit z1 start and stop switch SS, a coil section of the above-mentioned electromagnetic contactor MCo-MC4, etc. In addition, the moder MI9M2 requests that the electromagnetic contactors MO, Me4 be turned on.
is directly connected to the power supplies R, S, and T to perform constant speed operation, and when the electromagnetic contact 5MC7 or MC is turned on,
Through the variable frequency inverter equipment NV, the moder M,
Alternatively, M2 performs variable speed operation. In the figure, when the switch SS is turned on, stable power is supplied to the microcomputer μco via the transformer T1 power supply unit 2.
The signal is sent to the power supply terminal E of No.n, and operation preparation is completed.

The same reference numerals as in FIG. 2 are the same. In the figure, Hl is the whitening command pressure of the pump, H2 is the pump head command pressure, and curve ik is the Q and -H performance at low speed N1 when operating with one variable speed pump. , curve e is the composite performance when the variable speed pump is running in parallel with the constant speed pump at the operating speed N.

In addition, the curve f is the Q-H @ formation performance when the lowest speed pump is running in parallel with the constant speed pump at the lowest speed Nrm. This curve is set so that it intersects with Q when the variable speed pump is operating at a high speed Nm, and with F which satisfies the target pressure Ho on the monthly performance curve f. That is, when the variable speed pump reaches the maximum speed and the pressure in the water supply pipe 9 reaches the whitening pressure H1 described above as the amount of water used increases, the constant speed pump is started and the variable speed pump is started. Driving type level N
max to lyl ws, and from this state, as the amount of water used decreases and the pressure in the water supply pipe 9 reaches the above-mentioned table pressure H2, the constant speed pump is stopped,
The variable speed pump has a maximum speed of 19ma from the minimum speed NM.
x.

FIG. 7.8 is a flowchart showing the control procedure of FIG. 5. To explain in more detail with reference to these drawings, a program is installed in the microcomputer μCon so that the operation of the pump device can proceed according to the flowcharts shown in Figs. 7 and 8. Do it like this.

A cheater with initial velocity N in to memory M, memo I
Transfer the delta of N and J speed to J y2, transfer the data of the lowest speed Nm1g to memory M, transfer the data of maximum speed N+X to memory M4, transfer the data of speed change control width ΔN to memory M, and memo IJM. , the data of brightening pressure H1 to
Data of target pressure H6 is transferred to memory M7, data of table pressure H2 is transferred to memory M8, and data of magnetic contactor M is transferred to memory M9.
Co+ M O20N data to memory MIO to magnetic contactor MCo, MC2, MO4ON
data to the memory M ) H of the magnetic contactor M O6, M C3ON
data to memory M-, 2 through electromagnetic contact IYC. , +vc3. Mc
.

ON data, Well, store it in each memory.

The microcomputer μcon has the following 3 to 6 steps, 6 magnetic contactors (in this example, 4 contacts for the pump)
Output port ○
When sent from UTA to interface O, the initial and speed N is the operating speed of the variable speed pump.
ir+ command from output port 0UTB D/A
It is sent to the variable frequency inverter device NV1 via converter F2. It's scary, so it's a variable speed pump! ” starts operation at the initial speed Nin. In the unproductive example, data of speed 141 is entered as the initial speed Nin.

Next, steps 8, 9. The IQ compares the pre-stored target pressure H8 with the signal sent from the pressure sensor 8, and as a result, the amount of water used in iφ decreases, and the signal sent from the pressure sensor is higher than the target pressure H6. If it is large, 11
Proceed to step, execute the deceleration process, store the -P degree as the new initial speed Nin in the memory M, and
Return to step 3, and repeat this until the force detected by the pressure sensor matches the pressure detected by the pressure sensor. If both are equal, do not shift and return to step (3). If the pressure calibrated by the pressure sensor is lower than the target pressure H8, the process proceeds to the 12-1A step, where the current normal rotation speed is compared with the lifting height N2X, and the maximum speed N2 is determined. If X has not been reached, increase the speed in 15 steps and set the speed to the new initial speed Wi.
Store it in memory M1 as n, return to ■, target pressure and 1
Check the pressure sensor. Repeat this until the measured pressures match. Once the maximum speed N rnax is reached,
Proceed to the next steps 16 to 18, compare the brightening command pressure H1 with the pressure detected by the pressure sensor, and if the pressure detected by the pressure sensor is not specified in H1, return to step 1.4, but the amount of water used will be If the pressure increases by more than Qp and reaches less than H2, the electromagnetic contactors MCo, MO, MC! Output the 4'ON data from output port (OUTA) and use A2 as a constant speed pump.
At the same time, a signal is output from the output boat 0UTB to reduce the operating speed of the variable speed pump 41 from the maximum speed Nmax to the minimum speed 14mln.

As a result, if the swimsuit used is QF without any change, there will be no excess or deficiency in the amount of water supplied as described in the conventional technology.
The operating point of the pump is on point F. Next, in step 23, after setting the waiting time necessary for shifting, 2A to 2
In 6 steps, the target pressure Ho and the pressure detected by the pressure sensor are compared, and if the two are equal, no gear shifting is performed (c
Return to rr, and if the pressure output by the pressure sensor is lower than the target pressure H8, in steps 28 to 29, determine whether the full operating speed has reached the maximum speed + i, N max K, and record the maximum speed history. If the speed has reached N2X, do not shift and return to @, and if the maximum speed Nmax has not been reached, increase the speed in 30 steps and store that speed in the memory M as the new initial speed Nin. Then, return to @ and repeat this until the target pressure H8 and the pressure detected by the pressure sensor become equal.

As a result of the determination, if the pressure detected by the pressure sensor is higher than the target pressure H8, it is determined in steps 61 to 53 whether the full operating speed has reached the decreasing speed Nmu, and if not, in step 54, The deceleration process is executed and the speed is stored in the memory M as a new initial speed N1n, and this process is repeated until it returns to 0 and the target pressure H8 becomes equal to the pressure detected by the pressure sensor. In addition, when the minimum speed Nmm has been reached, in steps 65 to 37, the table command pressure H2 is compared with the pressure detected by the pressure sensor, and if the pressure detected by the pressure sensor is lower than the table command pressure H2. Return to step 33, and if the amount of water used decreases to more than Qe and the pressure detected by the pressure sensor reaches H7 or more, proceed to steps 39 to 41 to close the magnetic contactor M.
OOe Only MC2 outputs ON data) OUT
Output from A, constant speed key 2 pump! At the same time, the operating speed of variable speed pump ÷ 1 is changed from the minimum speed Nm1n to the maximum speed IJ.
A signal to increase the speed to max is output from the output capo (OUTB). As a result, there is no excess or deficiency in the amount of water supplied as described in the prior art, and if the amount of water used remains unchanged and Qe, the operating point is E.

In this way, according to this embodiment, multiple pumps can be whitened and
Since there is no extreme imbalance between the amount of water supplied and the amount of water used, there is an effect of suppressing pressure fluctuations.

In the above example, as the amount of water used increases, the variable speed pump that was operated first reaches its maximum speed, and the pumps are operated every time the pressure reaches the platform command pressure of multiple pumps, which is slightly lower than the target pressure. While sequentially starting the other pumps that have not been operated, the operating speed of the variable speed pump that was operated first is set so that the above-mentioned table command pressure point intersects with the parallel composite performance curve of the variable speed pump and the constant speed pump. and the variable speed pump reaches the minimum speed as the amount of water used decreases from the operating state of the variable speed pump and the plurality of pumps,
Every time the pressure reaches the platform command pressure of multiple pumps, which is slightly higher than the target pressure, the operating pumps are stopped one after another, and the operating speed of the variable speed pump is changed from the minimum speed to the maximum speed. Because it can suppress large pressure fluctuations when the number of units increases or decreases, it has the effect of providing a stable water supply without adversely affecting the equipment or piping used.

Next, another embodiment of the present invention will be described. In other words, in this embodiment, when water is supplied by changing the operating speed of a pump depending on the amount of water used, a variable speed control device that controls the speed of a modele that drives the pump and a water supply pipe are used. a pressure sensor provided therein; a microcomputer that inputs a signal generated by the pressure sensor, performs processing, and instructs a speed change control signal to the variable speed controller; and a microcomputer connected to an interrupt terminal of an input port of the microcomputer; When the variable speed control device trips, the variable speed mode is disconnected from the variable speed control device, connected directly to the commercial power supply, and the pump is powered off. This is a water supply device that uses a variable speed pump that is characterized by intermittent operation.

In addition, in systems that supply water by changing the operating speed of the pump depending on the amount of water used, the operating speed of the variable speed pump, which matches the natural frequency of the pump device's casing, base, piping, etc., is not output. This is a water supply device that uses a variable speed pump.

Further, the variable speed control device and the variable speed pump mode are connected to an electric and magnetic contactor that connects the variable speed control device and the variable speed pump mode to the speed control device, and the electromagnetic contactor that connects the pump mode directly to a commercial power source, and the variable speed control device is provided with speed change control. A microcomputer that commands a signal, a pressure sensor installed in the water supply pipe, an A/D converter that A/D converts the signal generated by the pressure sensor and sends it to the large port of the microcomputer, and the output of the microcomputer. An interface in which the electromagnetic contactor opens and closes in response to a signal, and a D/A converter that D/A converts the speed change command signal output from the output boat and sends it to the input terminal of the variable speed control device. This is a water supply system that uses a variable speed pump that was developed quickly.

Hereinafter, such an embodiment will be explained in detail with reference to FIG. 1 and FIGS. 9 to 15. FIG. 1 shows a configuration diagram of a Posip device according to an embodiment, in which a pressure tank 11 is added to the one already described. FIG. 9 shows a control circuit of the speed control device of the present invention, which is almost the same as the control circuit already explained in FIG. 5, with the following new additions in this embodiment. K is the contact N V Ta that trips the variable frequency inverter due to a malfunction, and the pull-up resistor R1! This is a first interface consisting of NOT, and its signal line is connected to the interrupt input terminal of the input port NB of the microcomputer μcon. Figure 10 shows the change in Q-H performance when the operating speed of a variable-speed pump changes.
An example of a single pump is shown below. Figure 11 shows the Q-H characteristic curve of the pump when the variable frequency inverter equipment NV trips and the modele is connected directly to the power supply without going through it, and two Voleps are operated. The horizontal axis shows the pressure H, and the vertical axis shows the pressure H. Curve a is Q, -H of one pump
The performance curve - curve is a combined Q-H performance curve obtained by parallel operation of two pumps with the same characteristics, where pressure H1 is the starting pressure of the leading pump, H2 is the stopping pressure, and similarly pressure H5 is the starting pressure of the follower pump. H4 is the stopping pressure. Note that H3 is set to be higher than H6. Or Q.

~Q4 is the pump discharge amount corresponding to these pressures. FIG. 12 shows a memory map when the microcomputer μcon performs interrupt processing.

That is, when the variable frequency inverter device NV trips, when this signal is sent to the interrupt terminal of the input capacitor NB of the microcomputer μcon, this signal is processed preferentially and the interrupt vector FFFF (16)
, the memory ML stored in FFFE (16), 1
, 11) (Jump to and perform the subsequent processing. Figures 13 and 14 are flowcharts of the program showing this process, and Figure 15 shows that the fundamental frequency of the pump matches the natural vibration of the pump base, piping, etc. 2 is a flowchart showing programs for preventing this from happening.These programs are stored in memory in advance.

In Figs. 9 and 10, the pump 41 (modele 61) is now producing water volume Q. Assume that the pump is operating at point C of the pump characteristic curve. At this time, if the amount of water used changes to Q4, the pressure inside the water supply pipe 9 increases to Hl. At this time, the pressure sensor 10 detects this pressure and issues an electric signal. The microcomputer μcon compares this measured pressure H with the target pressure stored in the microcomputer μcon, and uses a signal that decreases the measured pressure by 10Δ, which is higher than the target pressure H8, as the measured pressure. Output repeatedly until a match is found. That is, the operating speed of the pump is decreased by ΔN, and the operating point is Q, Pass 020, -1
) Oゝ was moved blindly, and the pressure was H2+N2-? The target pressure is reached from H3 to H0. Similarly, when the amount of water used increases, the target pressure is kept constant by performing the opposite operation.

Although not shown in Figure 10, if the amount of water used increases and cannot be covered by one pump, another pump is added, reducing the amount of water used and making the water supply less than the demand. If the capacity is exceeded, one pump is mounted on the stand. In this way, water is supplied while keeping the water supply pressure constant by increasing or decreasing the number of pumps depending on the amount of water used. However, if the pump trips due to a problem with the variable frequency inverter, the pump will stop, causing a water outage and disrupting daily life. Therefore, a non-inventive embodiment that takes measures against this problem and improves it will be specifically described. 90 In FIGS. 12 to 14, as mentioned above, when the variable frequency inverter @ installation NV trips, the interrupt vector is selected preferentially, and the F
F'FF (16) and FFFF1 (16) are the memory addresses ML that are being stored.

Executes instructions after MH. For convenience, the starting addresses of one step shown in FIG. 13 are assumed to be ML and MHl. That is, initial settings are performed in one step.

Its contents are as follows.

The data corresponding to the starting pressure H7 of the preceding pump is stored in the memory MA, the data corresponding to the following pump pressure H7 is stored in the memory MB, and the starting pressure H of the following pump is stored in the memo IJMO.
The data corresponding to 3 is stored in the memory MD, and the de-ON data corresponding to the stop pressure H4 of the following pump is stored in the memo IJMF.
Electromagnetic contactor Meo.

Transfer MO and ON data to memories M and G using electromagnetic contactor MC.
j6. Stores data of Mc, sM'a, and ON.

However, the starting pressure H3 of the follow-up pump is set to be higher than the target pressure H6.

Next, in two steps, the pressure signal detected by the pressure sensor 8 is converted into a digital signal by the A/D converter F1, and the signal is input from the input port NA of the microcomputer μcon and loaded into the A register. In 6 steps, the data in memory MA (data on the starting pressure H1 of the preceding pump) is transferred to the B register, in 1 step index register X is cleared to 0, and in 5 steps the contents of the A register and B register are compared. As a result, if the A register is larger and has not reached the starting pressure of the preceding pump, repeat this step again until the starting pressure is reached; if the A register is smaller and has reached the starting pressure of the preceding pump H8 or lower, then , proceed to step 6, where the LSD (bo bit) of index register
Determine whether or not is 0. If it is 0, load the contents of the memory ME containing the data of No. 1 pump ON, that is, MOo, MO, ON, into the A register, and if it is 0, load the data of No. 2 pump ON, Meo, into the A register in 8 steps. M
Load the contents of memo IJMF containing e4. For the sake of explanation, I will now say A.? It is assumed that the data of the memory ME is loaded into the star. Then, in 9 steps, the data in the A register is output.
) When output from OUTA, transistors Tro and T
r, becomes conductive, relay xo,x, is energized, and electromagnetic contactor M (:! o, Mc.

is energized. For this reason, these contacts are closed.

MO, PL are closed, moder M1 is variable frequency inno (-
Direct power supply R9S without going through Yusou NV NV,
At the 010 step to start operation, the index register X is incremented. At the 11th step, the necessary waiting time t is executed so that the pressure sensor does not take in the pressure pulsation at the time of startup. At the 12th step, the index register X is incremented. , the ID number detected by the pressure sensor 8 is manually input from the input port ENA, loaded into the A register, and 1! Is the stopping pressure of the preceding pump H at step I? Load the contents of memory MB containing data into the B register.

Then, in step 1A, it is determined whether the pressure -ix detected by the pressure sensor B has reached the stop pressure H7 or higher. As a result, if the pressure detected by the pressure sensor 8 has reached the stop pressure TIW7 or higher, in this case, the process jumps to step 17, and after executing the waiting time of a certain period t, which is sufficient to suppress the starting frequency, i6. Execute the is step and stop the No. 1 pump A1 that is running at t7,
Jump 5 steps and execute the process again.
Ru. However, since the index register is incremented every time the 10 steps are executed, the LSD (bo bit) of the index register E in the step becomes [1, 1] alternately, and the No. 1 pump and No. 2 pump are operated alternately. will be carried out.

As a result of the judgment in step 1A, if the pressure detected by the pressure sensor 10 is lower than the stop pressure H2, then in step 1B, 1'9.20, the pressure in the water supply pipe 9 starts the follow-up pump. Judgment is made as to whether the pressure has reached H3 or lower, and if the result is that it has not reached 12
Jump to the step and re-execute the following process, and if the starting pressure has reached H, 15, or below, 21.2.
Memory MG (parallel operation MO8, MC,
, MO4ON) is output from the output port) OUTA. As a result, the transistor T r o+ T r
1+ T r4 conducts, relay X. , X, ,
+ Close MC4a. Therefore, moder M, tM
z is connected directly to the electric currents R and S without going through the inverter NV.
, TK connection, and the No. 2 pump (if the No. 2 pump takes the lead, the No. 1 pump follows), resulting in parallel operation. After this, in step 23, after waiting for a certain period of time for the same reason as mentioned above, steps 24 and onwards are executed.In steps 2A and 25. A judgment is made as to whether or not the above limit has been reached. If not, step 27 is executed, the process returns to step 24, and subsequent instructions are executed. If step 297 has been reached, step 27 is executed. Determine whether the bo bit of index register X is O at the step. If it is 0, leave the No. 1 pump at 30°32 steps and stop the No. 2 pump. If it is 1, leave the No. 2 pump at 3L 32 steps. , and stop the No. 1 pump. After executing these instructions, the program returns to step 9 and repeats the above operations until the interrupt is released (until the trip of the inverter device NV is released).

Next, another embodiment will be described. When the fundamental frequency of the pump's pressure pulsations matches the common frequency of the pump casing, pace, piping, etc., they resonate and generate vibration noise. That is, the pump generates pressure pulsations every time the trailing edge of the impeller blade passes the winding start portion of the porute casing, and noise is generated due to interference between the impeller and the casing.

The fundamental frequency of this pressure pulsation is f −−, −, ,,,...
... becomes ■.

Here, 2 = number of blades of the impeller n: rotational speed (rpm).

In addition, in general, the natural frequency f of photography is the following formula % formula % Here, k: Spring constant W: Weight g: Acceleration of gravity.

In order for the pump to operate stably without causing vibration noise, it is sufficient to prevent this fundamental frequency from coinciding with the characteristic frequency of the pump casing, base, piping, etc.

In FIGS. 9 and 15, initial settings are performed in one step as follows.

Memory M stores data on target pressure H6, memory M2 stores data on initial speed Nin, IJM stores data on minimum speed NMA, IJM4 stores data on maximum speed N.
The data of max is stored in the memory M, the data of the speed change control width ΔN is stored in the memory M6, the data of the electromagnetic contactor MCo and MO2ON is stored in the memory M7, and the natural frequency f of the pump casing is stored in the memory M7.

The data of the natural frequency f2 of the pump pace is stored in the memory M8, and the data of the natural vibration frequency f3 of the piping is stored in the memo IJM'. In addition, these specific number of images are based on the above-mentioned ■
It is determined by a formula, but if the calculation is difficult due to a complex shape, it can also be determined by measurement using a percussion method or the like. In the next two steps, set the target pressure H to the A register.
8 is stored in the memory M1, and in 3 steps the pressure in the water supply pipe 9 is detected by the pressure sensor 10 from the input port NA and inputted, and in 5 steps the target pressure H8 and the pressure sensor 10 are detected. As a result, the pressure detected by the pressure sensor 10 is compared with the target pressure H.
If the value is higher than 8, the process jumps to the 1 step, waits for t seconds, returns to the 3 step, and continues the process from this point onwards. If the pressure detected by the pressure sensor 10 has decreased below the target pressure H8, the data of the initial speed Nin is output in step 6.7.
output to make the variable speed pump ready to start at the initial speed. In the next step 8.9, pump 41 is used, but pump ≦, mo) #4; # of course may also be used. ) is output from output port 0UTA. Therefore, the variable speed pump starts operating at the initial speed. In 10 steps, the waiting time required for the pressure to stabilize after startup (
time delay) is executed, and in step 11, the pressure in the water supply pipe 9 is detected again by the pressure sensor 10, inputted from the input port INA, and loaded into the A register.
In step, the target pressure H8 and the pressure detected by the pressure sensor 10 are compared. As a result of the determination, if the pressure detected by the pressure sensor 10 is higher than the target pressure H8, 13
Jump to the step, load the initial speed data into the A register, compare the initial speed Nin and the minimum speed N= in 1A step, and if they are equal, do not change the speed, and if the initial speed data is greater 15. In 16 steps, the data on the shift control width ΔN is subtracted from the initial speed and 1fNin data, and in 17 steps, the data in the memory "?+M8+M9" containing each natural frequency data is bit-inverted, and in 18 steps Memory M with bits reversed by ?+
M8. M, data (■ here because it is inverted.

Mg, M (expressed as , ) and the data of the A register (contains data obtained by subtracting the shift control width ΔN from the initial speed Nin) are ANDed and loaded into the A register, and the above-mentioned The operating speed that matches the natural frequency is masked. In step 19, the operating speed thus obtained (loaded into the A register) is stored in the memory υM2 as new initial speed Q) data.
Output this new driving speed data in 20 steps.
) output from OUTB and decelerate. Then, in step 29, a waiting time is executed for the time necessary for the pressure to stabilize after the gear shift, and the process returns to step 11. From here, the process continues until the pressure detected by the pressure sensor 1o becomes lower than the target pressure H8. Repeat the loop described in ■. 12
If the judgments in the steps are equal, the process proceeds to the 29th step without changing gears, and if the pressure detected by the pressure sensor 1o becomes lower than the target pressure H6 as a result of the judgment in the 12th step, the process jumps to the 21st step. The same process as in the loop described above is executed, but in this loop ■, the initial speed N1n
Kf speed control width ΔN is added, and the speed increase process is repeatedly performed until the target pressure and the pressure detected by the pressure sensor match.

As described above, according to this embodiment, when the variable frequency impark device trips, the interrupt function of the microcomputer, which was originally used for speed control of the variable speed mode, operation order control, and other purposes, is utilized. The pump is connected directly to the power supply without going through this, and the pump continues to operate.
Not only will there be no water outage, but you can also use the same cost-effective microcomputer as mentioned above. In addition, the operating speed is masked to match the natural frequency of the pump casing, base, piping, etc., so that no output is produced, so there is no resonance, and no abnormal vibrations or whispering noises occur. .

Note that in the embodiments already described, the vibration conditions of the pump and piping system are stored in advance in the storage device, and then the pump operation is controlled. By installing the pump and operating the pump for the first time or at regular intervals, the speed range where vibration is likely to occur can be detected and memorized. It can also be configured to speed up and slow down.

Other embodiments shown in FIGS. 16 to 22 will now be described. First, explanation will be given with reference to FIGS. 16 to 19. Figure 16 is a configuration diagram of the liquid supply device. 1 is the water tank 2 is the suction pipe, 31.3
2 is a gate valve, l is a pump, 6 is a mode that drives the pump 4, 8 is a check valve, 11 is a pressure tank that holds liquid when the pump is stopped, 10 is installed in the water supply pipe 9, and A pressure sensor calibrates the pressure and generates an electric signal in accordance with the pressure, and 12 is a flow sensor. Fig. 17 shows the control circuit of the control device of the embodiment, where MOB is the breaker for the main circuit, MO is the coil of the electromagnetic contactor, MCa is the contact point, and N'V changes the rotation speed of the variable speed mode. variable frequency inverter device (in this example, a variable frequency inverter installation is used, but primary voltage control, eddy current coupling, and other variable speed control installations can also be used as means to change the operating speed of the moder. It is not something that will be done.

) TH is a thermal relay for overload prevention, μCon is,
Central processing unit (hereinafter abbreviated as CPU) memory M,
A microcomputer consisting of power terminal E, input port NA, NB, output port) OUTA and 0UTB, F is an analog signal or digital signal ((converted, and the signal is converted and sent to the input port 1- I
The A/D converter sent to NA, and the D/A converter F2 converts the speed command signal (digital signal) output from the microcomputer μcon into an analog signal and sends it to the input terminal of the variable frequency inverter device INV. It is a vessel.

Furthermore, X is a transformer T1 power supply unit z, fAm, stop switch SS, magnetic contactor coil Mc, ) run sister positive, relay X2. This is an operation circuit section consisting of a resistor R1. In this embodiment, the pace of the transistor Tr is connected to the bO bit of the output port 0UTA, so when the data of 0X (16) is output from the output port OUTA, the transistor Tr becomes conductive and the relay ,
And the electromagnetic contactor MO is energized. Furthermore, the input port NB connects the contact F'E+ of the flow rate sensor 9 to the resistor R
When this contact P8 closes, the connection bit of the input capacitor NB becomes 0, and this signal is read into μcon. Alternatively, the flow rate sensor is not a contact output type, but an electrical signal (current or voltage).
An output type may be used, an A/D converter may be provided, and this signal may be read from the input port NB. It is not limited to these. Also, insert a breaker MOB,
When the switch SS is closed, the power from the power supply unit z is transferred to the microcomputer μCo via the transformer T.
n, and preparation for operation is completed. 18th Ho
is the target pressure, Hl is the maximum rising pressure when pump 4 is stopped and the holding pressure of tank 11, F2 is the pressure when restarting the pump,
Curve a shows the Q-H performance of the pump when the pump operating speed is the maximum speed Nmax, and similarly, each curve shows the pump operating speed N1. Curve C shows the operating speed N29, curve Nd shows the minimum speed 1 qmm, curve e shows the stopping speed N39, curve f shows the Q, -H performance of the pump at restart speed N4, and the water volume Q
N is the pump stop command water volume, and the flow rate sensor 12
is set to this value. In addition, the minimum speed NM is set to a speed that satisfies that the pump 4 stop command flow rate Q= and the curve d intersect at point A, and similarly, the speed at stop N3 is determined when the pump stop command flow rate Q#I and the curve e The speed N4 at restart is set to a speed that satisfies the intersection at point A', and the pump stop command flow rate Q
The speed is set to satisfy that m and curve af intersect at point A'', and pressure HI+H2JTO is determined to satisfy, for example, the following relational condition.

Here, Cap: When the amount of water used is Qmq, the time required for the restart pressure to decrease from H2 to the target pressure H6 ■o: The air volume in the tank when the target pressure is H8 ■2: The tank when the restart pressure is H2 Internal air volume H: Initial pressure of the tank (expressed in absolute pressure) ■ = Desired air volume inside the tank when the initial pressure is H Approximately 10 to 5017 m in water volume) H2゛: Restart pressure (11b, shown in relative pressure) Hl
: Retained pressure () ■, : Air volume in the tank when the retained pressure is H8 t2: When the amount of water used is QI==1, from the retained pressure H0,
This is the time until the restart pressure decreases to H2.

That is, the pump 4 is stopped and restarted by the restart pressure H2, but it takes several seconds of acceleration time to reach the speed N4. Therefore, in order to prevent the mold 5 from being burnt out due to pressure return during this period, a sufficient stopping time t is ensured using the 0.0 formula, and the holding pressure H1 is determined. However, if the amount of water held in the pressure tank is sufficient to cover the amount of liquid demanded during the few seconds when the capacity of the pressure tank accelerates, there is no problem even if the restart pressure H2 is set to H8. By the way, as the amount of water used changes, the pump 4 supplies water to the water faucet 13 at the end while continuously changing the operating speed from Nris to Nmax while keeping the pressure in the water supply pipe 9 constant at H8. It is something we will do. The point to 40 points is the operating point at that time.

FIG. 19 is a flowchart showing the control flow of the control device of this embodiment, and the control flow is not particularly limited to this embodiment. Furthermore, a program is stored in the microcomputer to be executed according to the flow of this flowchart. Now, a detailed explanation will be given using these drawings. In Fig. 19, initial value settings are omitted, but target pressure H8, minimum speed pm, maximum speed Nm
x.

Initial speed Nin, speed change control width ΔN, speed when pump is stopped N
3. Speed at restart N2. It is assumed that data such as the restart pressure H2 and the pump stop command flow rate Qm have already been set. 5. 6. In step 7, the target pressure H0 is compared with the pressure detected by the pressure sensor 10, and the pressure detected by the pressure sensor 1 is
2 if the detected pressure of 0 is smaller than the target pressure H8.
The commands after step 0 are executed, but if the amount of water used is small, such as at night, and as a result of the above judgment, the pressure detected by the pressure sensor 10 is higher, 8. 9;1
At step 0, determine whether the speed of full operation has reached the minimum speed NN. If not, execute steps 16 to 19 and continue full operation until the target pressure and the pressure detected by the pressure sensor match. Shift control width Δ
Decrease by N and return to step 4, repeat this loop, and if the minimum speed Nll is reached, move on to the next step.
Proceed to step 1, and here it is determined whether the flow rate sensor 12 has detected the stop flow rate Qm of the pump 4. If it has not detected it, return to step 10, and from here on, a time delay is executed again. , the pump 4 continues to operate at the minimum speed Ntm, and then outputs the output for the time necessary to accelerate the operating speed N at the time of stop in 13° 11.15 steps, stops the pump, and proceeds to step 2. Return. At this time, if the amount of water used does not change according to QMs, the pressure in the pressure tank 11 and water supply pipe 9 will increase to H3.
Therefore, during this period, the liquid is supplied using the amount of liquid held in the tank, and then in two steps the pressure in the pressure tank 7 and water supply pipe 9 is detected by the pressure sensor 10, and this is the pump restart pressure
It is determined whether the pressure has reached 2 or less, and if it has not reached it, the determination is executed until it is reached. As a result, if the pressure inside the pressure tank decreases due to the outflow from the pressure tank 11 and reaches the restart pressure H2 or less, then outputs speed N4 in 3 steps and restarts the pump. Thereafter, when the amount of water used is small, such as at night, the above-mentioned operation can be repeated. or,
As the amount of water used increases, the judgment result at step 7 is that the pressure detected by the pressure sensor 10 becomes lower than the target pressure H8. If the high speed has not been reached, the speed is sequentially increased by the shift control width ΔN from the full operating speed until the target pressure and the pressure detected by the pressure sensor match. As described above, according to this embodiment, for example, when the pump is stopped, the maximum speed is output and the pump is not stopped, so it is possible not only to suppress pressure fluctuations in the water supply pipe, but also to downsize the pressure tank. Therefore, the equipment cost of the liquid supply device can be reduced. In addition, when the amount of water used is low, such as at night, the pump stops, and when it starts, it starts at an appropriate speed, so the starting current can be suppressed, reducing operating power costs.

Next, another embodiment will be described with reference to FIGS. 16, 17, and 20. The operating characteristic diagram in FIG. 20 is obtained by adding intermediate operating speeds N, , N, and Q-H performance g and i at this time between the speeds Nm and N8 in FIG. 18. still,
In this example, the intermediate driving speed "5 + N 6" is set to 2.
Although it is divided into stages, it is not limited to this and may be implemented in as many stages as necessary.

When the pump stops, instead of outputting the stop speed N3 all at once and stopping the pump 4, it outputs the operating speeds N, N, in the middle and gradually increases the operating speed. , the pressure inside the pressure tank is raised and stopped.For example, steps 10 to 15 and steps 1 to 2 in Figure 19 can be realized by changing the microcomputer program as shown in the flowchart in Figure 22. can. That is, in the same figure, when the flow rate sensor 12 detects the pump stop command water amount Q= in step 11,
Execute the time delay for t2 hours in 2 steps,
After continuing to operate at the minimum speed IJ++m, at step C,
Output the speed N6, execute the waiting time t longer than the acceleration time of the pump in the D step, and judge again in the E step whether the flow rate sensor 12 is detecting the stop command water amount Qmm, and if it is detected, is the next F.

During the waiting time t4 which is longer than the acceleration time at step C, the speed N
6 is output, and in step J it is determined again whether the flow rate sensor 12 is detecting the stopped water amount Q=. (above), the speed Ns is output, and then the pump 4 is stopped and the process returns to step 2. As a result of the judgment in these two steps, if the pressure inside the water supply pipe 9 has dropped to below H2, the intermediate speed N6 is adjusted for t1 time (acceleration time) before outputting the restart speed N4 as described above. output only for a period of time longer than necessary. In addition, in order to keep the pump start/stop frequency sufficiently low, t2+ "!
+t4+t5 can also be determined appropriately.

As described above, in this embodiment, when the pump is stopped or restarted, the speed at intermediate stages is output gradually to suppress the sudden rise in operating speed and pressure, so that It becomes possible to suppress pressure fluctuations to a much lower level, and it becomes possible to suppress the starting current even lower.

Next, another embodiment will be described with reference to FIG. 21.

In the figure, the minimum speed Nm is determined so that the cut-off pressure S of the -H performance curve d is in contact with the target pressure H8,
When the microcomputer μcon outputs the minimum speed Nm, the pump 4 is stopped and the same operation as in the previous two embodiments is performed, and the detailed explanation will be omitted since it overlaps with the above.

According to this, since the flow rate sensor 12 can be omitted, the cost of the liquid supply device can be reduced accordingly.

According to such an embodiment, the speed when the pump is stopped is set to be low within a range that satisfies the frequency of starting and stopping the pump, and the speed when the pump is restarted is set so that the pressure in the water supply pipe and the pressure in the tank are low at the time of restart. Since it is set so that the pressure does not drop below the target pressure during acceleration, pressure fluctuations can be kept small and have the effect of not adversely affecting the equipment used. Further, since the starting current can be kept low, there is an effect that the operating power cost can be reduced. Furthermore, the control device can be simplified by IC and microcomputer control, and the pressure tank can also be downsized, making it possible to obtain an inexpensive liquid supply device.

[Effects of the Invention] As explained above, the present invention is composed of a pump, a water supply pipe provided on the discharge side of the pump, and a pressure sensor provided in the water supply pipe, and the water supply is controlled according to the amount of water used. When carrying out the process, the target pressure stored in advance is compared with the actually measured pressure in the water supply pipe, and the variable speed pump is driven so that the measured pressure matches the target pressure. a variable speed control device that controls the speed of the variable speed mode; a microcomputer that inputs the signal generated by the pressure sensor, processes it according to a pre-stored program, and issues a speed change command to the variable speed control device; According to the present invention, the pump can be operated much more stably than in the past.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a pump device for explaining the configuration of a basic embodiment of the present invention, and FIG. 2 is an operating characteristic diagram when the pump of the pump device is operated at constant speed or variable speed. FIG. 3 is a block diagram for explaining the configuration of a control device of a conventional pump device, FIG. 4 is a diagram for explaining pressure changes during operation of a conventional pump device, and FIG. 5 is a diagram for explaining pressure changes during operation of a conventional pump device. A block diagram showing the control circuit of the control device of the basic embodiment, FIG. 6 is an operating characteristic diagram of the embodiment shown in FIG. 7, and FIGS. 7 and 8 are basic diagrams of the embodiment shown in FIG. 5. Explain the action,
9 is a block diagram showing a control circuit of a control device according to another embodiment of the present invention. FIGS. 10 and 11 are operating characteristic diagrams of the embodiment shown in FIG. 9. 13 and 14 are flowcharts for explaining the operation of the embodiment shown in FIG. 9, and FIG. 15 is a diagram showing a part of the memory map of the embodiment shown in FIG. FIG. 16 is a flowchart for explaining the operation of the example, FIG. 16 is a configuration diagram of a pump device for explaining the configuration of another embodiment, and FIG. 17 is a control circuit of the control device of the embodiment shown in FIG. 16. The block diagram to be explained, FIG. 18 is the operating characteristic diagram of the embodiment shown in FIG. 16, and FIG. 19 is the operating characteristic diagram of the embodiment shown in FIG.
6 is a flowchart for explaining the operation of the embodiment shown in FIG. FIG. 22 is a flowchart illustrating the operation of the control device to realize the operation method shown in FIG. 20. +2 9... Water supply pipe, 10... Pressure sensor, 41. Soil container...Pump, ■NV...Variable speed control device, μCo
n...Microcomputer, "11M2...
Magnetic contactor, 0UTA, 0UTB... Engineering/○ port, F2...D/A conversion? 5, G... Interface 663 1st figure world 2 days 0Hθt Qct6+A -11110 dedicated 3 figure 4 figure H force relationship pressure barley relationship θ -- bud 11 figure O → boiling 13 ward; Q→ 17th Figure Kaya/9 Figure 21 Figure Q"'N Q-

Claims (1)

[Claims] In systems that are composed of multiple pumps, water supply pipes installed on the discharge side of these pumps, and pressure sensors installed in these water supply pipes, and supply water according to the amount of water used, The target pressure stored in advance is compared with the actually measured force in the water supply pipe, and the operating speed of the variable speed pump is changed so that the measured pressure matches the main tank drying force.
In addition, while increasing and decreasing the number of regular pumps, a variable speed control device is installed to control the speed of the variable speed mode that drives the variable speed pump, and a signal emitted by the pressure sensor is input. A microcomputer performs arithmetic processing according to a pre-stored program and instructs the variable speed control device to change speed, and converts the digital signal output from the first 110 port of this microcomputer into an analog signal, It is characterized by being composed of a D/A converter that outputs to the freezing inspection device, a variable speed pump that is operated by the signal output from the second 1/() port, and an interface between the electromagnetic contactors of the multiple pumps. Liquid dosing using a variable speed pump.