JPH0819915B2 - Variable speed pump operating device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water supply device using a variable speed pump, and more particularly to detecting a use state of a water supply device and automatically changing a target pressure. The present invention relates to a suitable controller for the water supply device.

[Background of the Invention]

Conventionally, as a control system for a water supply device using a variable speed pump, water is supplied while keeping the pressure on the discharge side of the pump constant, and the pressure on the discharge side of the pump is controlled by the resistance of the water supply line. There is a constant end pressure control method in which water is supplied by controlling along a curve. The former is generally adopted because the control system is simple and the equipment cost can be reduced. The latter requires a complicated control system and high equipment costs, but it is used for such an application in order to further enhance the energy-saving effect because the speed change range becomes wider if the piping loss is relatively large relative to the actual head. . In these control methods, since the target pressure is based on the total head, it is fixed or constant in any usage condition, and it is used, that is, divided into low, middle, and high rise zones of the building, and water supply equipment. It has not been recognized that the target pressure is appropriately changed and controlled depending on the type. This will be described in more detail. Fig. 5 shows the system diagram of the water supply system, 1 is a water receiving tank, 2 is a water absorption pipe, 3-1 and 3-
2 is a gate valve, 4 is a pump, 5 is a check valve, 6 is a water supply pipe,
Reference numeral 7 is a pressure sensor, and 8 is a flow sensor, which is used in the case of a constant end pressure control system. 9a to 9c are water faucets at the ends.
In other words, water is supplied from the receiving tank by the pump 4 at the end faucet.
Sent to 9a-9c. At this time, there are the above-mentioned two operation modes of the pump, which are controlled by a control system (not shown). FIG. 6 is an operation characteristic diagram in the case of the constant discharge pressure control system, in which the horizontal axis represents water amount Q and the vertical axis represents pressure H.
Curve A shows the QH performance when the pump is operating at the maximum speed N _MAX . Similarly, curves B, C and D show the pump operating speeds N, N and minimum speed N _{MIN, respectively.} Q-H when
Show performance. Ho is the target pressure (corresponds to the total head).
Actual lift (actual height up to the highest faucet based on the water absorption surface) H
a, the required terminal pressure (the desired pressure at the highest water faucet) Hp, and the loss H of the piping to the highest water faucet, etc., respectively. And in this method, for example,
When it fluctuates from Q _MAX , → Q a → Q b, the operating speed of the pump is controlled to N _MAX , → N a → N b → N _MIN, and the pressure on the discharge side of the pump is kept constant at Ho. Keep on. FIG. 7 is an operating characteristic diagram in the case of the constant end pressure control system, and the same reference numerals as those in FIG. 6 have the same meaning. In the figure, F is a resistance curve of a pipeline or the like, H is a pipeline resistance H _{T, and} the total head. Further, the target pressure is set in advance in an arithmetic unit (not shown) so that it is determined by the relationship of Ho = (Q) based on the resistance curve F when the flow rate Q is given. In this method, for example, demand for water is considered a case in which the change in Q _MAX, → Q c. At this time, this is detected by the flow rate sensor 8 shown in FIG. 5, and this signal is sent to the above-mentioned calculator (not shown), which is preset and is determined by the O ₂ point on the resistance curve F such as the pipeline. Set the target pressure. Next, this set pressure is compared with the pressure in the water supply pipe 6 (pump discharge pressure) detected by the pressure sensor 7, and the operating speed of the pump is controlled to be equal. In this case, the operating speed is N ha. As described above, water is supplied by controlling the operating speed of the pump so that the pressure on the pump discharge side follows the resistance curve F of the pipeline according to the fluctuation of the demanded water amount. However, according to the conventional technology, even if the water is supplied only to the low and middle zone, the actual pump head H
a, the required end pressure Hp was constant. If the equipment to be supplied with water is 9c or 9b in FIG. 5, the actual lift may be Hb, Hc, and the target value that was conventionally constant can be lowered by this amount, so the gear shift range is widened. Also, the required pressure of the faucet at the end is, for example, about 0.7 kg for the flush valve and shower.
/ Cm ² in general faucet 0.3 kg / cm ^2, 0.4 to the water heater
0.5kg / cm ² and going on is to look at safety in general, 1kg
It is about / cm ² . By setting the terminal pressure required for this depending on the water supply target, the target pressure, which was conventionally constant, can be lowered, and the gear shift range can be similarly widened. Energy saving is further achieved by widening the shift range, but this has not been recognized in the past.

[Object of the Invention]

In the conventional system, the actual head and the required terminal pressure are fixed regardless of the water supply location and the water supply target, but water is not always supplied to the high-rise zone, but water may be supplied only to the low-rise zone or the middle-rise zone. Also, the water supply equipment used in the water supply system has various desired pressures. The present invention has been made in view of such a point, and an object of the present invention is to change the conventionally fixed actual head and required terminal pressure according to a water supply point (height of a building, etc.), and to provide a variable speed pump. It is an object of the present invention to provide an operation control device for the variable speed pump, which is capable of widening the speed change range and further saving energy.

[Outline of Invention]

The present invention relates to a variable speed pump, a control device for controlling the speed of the variable speed pump, a water supply pipe arranged on the discharge side of the variable speed pump, and a faucet provided at the end of the water supply pipe. A pressure sensor provided on the water supply pipe for detecting the water pressure of the water supply pipe and outputting the water pressure to the control device, so that the pressure detected by the pressure sensor becomes a pre-stored target pressure on the discharge side of the pump. In a variable speed pump operating device for performing speed control of the variable speed pump, a signal corresponding to a predetermined installation zone is detected in accordance with the installation height of the faucet in the building by detecting the open state of the faucet. And a storage unit for storing a plurality of target pressures changed according to the installation zone and a signal corresponding to the installation zone from the detection unit and stored in the storage unit. Was done Means for selecting a target pressure based on a received zone-corresponding signal received from a number of target pressures, and the controller is configured to speed control the pump according to the selected target pressure. It is characterized by that.

[Action]

When the faucet provided at the end of the water supply pipe is opened, the detecting means detects the opened state, and the detecting means emits a signal corresponding to the installation zone. The control device which has received the installation zone corresponding signal selects a target pressure on the discharge side of the pump from a plurality of target pressures stored in advance according to the installation zone, and the pump according to the selected target pressure. Control the speed. As a result, the operating speed of the pump can be reduced according to the installation height of the faucet in use.

Example of Invention

An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a detailed view of the water supply pipe shown in FIG. 5, and in the case of the present embodiment, for example, sensors Sa to Sc are provided in or near the water supply equipment 9a to 9c for detecting the usage state of the water supply equipment. . The required terminal pressures of the water supply devices 9a to 9c are Hpa, Hpb, and Hpc, respectively. FIG. 2 shows a block diagram for performing the operation control of the present embodiment. Pw is a power source, MCB is a circuit breaker for wiring, INV is an inverter, IM is a variable speed pump 4 although not shown in FIG. The driving motor, X, is a receiver, which detects the usage state of the water supply equipment by the sensors Sa, Sb, Sc and receives a signal (for example, a wireless signal) emitted in response to this signal. For example, when the water supply device 9a is used, the sensor Sa emits a signal. Receiver X
When receiving this signal, the actual head is Haa and the required terminal pressure is Hpa. Water supply equipment 9a is not used 9b or 9b and 9c
Sensor Sb or sensor Sb
According to the signal from Sc, the actual head is Hab, the required terminal pressure is Hpb, and when only the water supply device 9c is used, the signal from the sensor Sc gives the signal corresponding to the actual head Hac and the required terminal pressure Hpc by the receiver X. It has a calculation unit which is issued to the control device CTL. This arithmetic unit can be composed of, for example, a microcomputer or an electronic circuit. Further, PS and FS respectively represent the signal oscillating parts of the pressure sensor 7 and the flow sensor 8 shown in FIG.
It should be noted that this embodiment will be described in detail below with reference to examples of respective control methods. FIG. 3 shows an operation characteristic diagram in the case of the constant discharge pressure control system according to the first embodiment, and the same reference numerals as those in FIG. 6 have the same meaning. In addition, the arithmetic circuit section of the receiving section X shown in FIG. 2 is preset so as to instruct the control section CTL as a target value in the next step during this control. Sensor Sa gives a signal → Actual head Haa → Required end pressure Hpa → Line resistance Ha → Target pressure Hoa, Sensor Sb gives a signal → Actual head Hab → Required end pressure Hpb → Line resistance Hb → Target pressure Hob, Sensor Sc emits a signal → Actual head Hac → Required end pressure → Hpc → Pipe line resistance Hc → Target pressure Hoc When comparing the pressure in the figure with the relationship in Fig. 1, Hoa uses water supply equipment 9a Target pressure (total head) when operating, actual head Haa, required end pressure Hpa, resistance H of pipe line, etc.
It consists of a. Then, for example, the load water amount is the maximum value Q _MAX.
If the point of O _o on Q-H curve A, is driven at a driving speed N _MAX. Of these water supply equipment, 9a is used up to the end, and when the demand water volume fluctuates, the sensor SA emits a signal as described above, so the target pressure Hoa is constant and the line from O _o point to O _s point In the meantime, the operating speed is also changed from N _MAX to N _MIN and water supply is continued. When the water supply device 9a is not used and 9b is used to the end and the demand amount changes, the signal from the sensor Sb is emitted, so the target pressure is Hob (the breakdown is the actual head H
ab, required end pressure Hpb, resistance Hb of the pipeline, etc., is constant and the operating speed is N'on this straight line between points O _l ′ and O _s ′.
To N _MIN ′ and continue to supply water. Even when only the water supply device 9c is used, the signal from the sensor Sc is similarly emitted, so that the target pressure is Hoc (the breakdown is the actual head Hac and the required end pressure).
The resistance Hc of the Hpc, the conduit, etc. is constant. On this straight line, this device is opened and closed according to the change in demand, and the O ₂ ″ point to O _s ″.
During the period, change the operating speed from N ”to N _MIN ” and continue water supply. As described above, it is remarkable that the shift range becomes wider than that in FIG. 6 showing the conventional example. FIG. 4 shows an operation characteristic diagram in the case of the constant terminal pressure control system according to the second embodiment, and the same reference numerals as those in FIG. 7 have the same meaning. In addition, the arithmetic circuit section of the receiving section X shown in FIG. 2 is preliminarily set to command the control section CTL as a target value in the next step in combination with the signal of the flow rate sensor FS during this control. It is what Sensor Sa gives a signal → Actual head Haa → Required end pressure Hpa → Total head HT
a → Pipe resistance curve Fa (target value), sensor Sb gives a signal → Actual head Hab → Required end pressure Hpb → Total head HTb → Pipe resistance curve Fb (target value), sensor Sc gives a signal → Actual Head Hac → Required end pressure Hpc → Total head HTc (target value)) The figure shows the actual head, the required end pressure, and the line resistance, etc. corresponding to each water supply device in FIG. For example, in the case of this embodiment, when the load water amount is the maximum value Q _MAX , that is, when the water supply device 9a is used, the sensor Sa emits a signal, so that the arithmetic circuit unit of the receiving unit X is preliminarily set. When the prescribed water amount is 0, the pressure is Haa + Hpa, and the water amount is Q _MAX .
A curve Fa connecting HTa is sent to the control unit CTL as a target value signal. Then, if 9a of these water supply equipment is used up to the end and the demand water volume fluctuates, the sensor Sa
, The target value is obtained by giving the flow rate signal detected by the flow rate sensor 8 to the curve Fa and the function Ho = (Q) determined by this, and on this curve Fa between the points O _o and O _s. Then, change the operating speed from N _MAX to N _MIN and continue _supplying water. When the water supply device 9a is not used and 9b is used and the demand amount changes, the signal from the sensor Sb is emitted, so that the arithmetic circuit unit of the receiving unit X causes the pressure Hab + Hpb and the water amount at the predetermined water amount O to be predetermined. The curve Fb connecting the pressure HTb at the time of 2 / 3Q _MAX is sent again to the control unit CTL as a target value signal. Then, when the demand water volume fluctuates, on this curve, from the O _l ′ point to the O _s ′, as described above.
Between the points, the operating speed is also changed between N'and N _MIN 'to continue water supply. Even when the water supply device is only 9c, the signal from the sensor Sc is similarly emitted, and the arithmetic circuit unit of the receiving unit X predetermines the pressure when the water amount is 0 Hac + Hpc and the water amount is Q _MAX / 3. The curve Fc connecting the pressure HTc of 1 is sent again to the control unit CTL as a signal of the target value. In this case as well, if the demanded water volume fluctuates in the same manner as above, water supply is continued by changing this curve between the O ₂ ″ and O _s ″ points and the operating speed between N ″ and N _MIN ″ as described above. . In this embodiment, the flow rate sensor can be omitted by preliminarily setting the relationship between the resistance curve and the operating speed of the pump in the arithmetic circuit section of the receiving section X. As described above, it is remarkable that the shift range becomes wider than that in FIG. 7 showing the conventional example.

〔The invention's effect〕

As described above, the present invention stores in advance a plurality of target zones on the discharge side of the pump corresponding to the installation zones of the set height in the building of the water supply apparatus, and the water supply apparatus in which the faucet is in the open state. Detecting the installation zone corresponding to, the target pressure on the discharge side of the pump is selected from a plurality of target values stored in advance based on the detected installation zone, and the target pressure is selected according to the selected target pressure. It controls the speed of the pump, which allows the pressure of the faucet in use to be reduced to match the installation zone,
The operating speed of the pump can be reduced. Since the required power of the pump is almost proportional to the cube of the operating speed, the present invention has an effect of saving a large amount of energy.

[Brief description of drawings]

FIG. 1 is a detailed view showing a sensor of a water supply pipe showing an embodiment of the present invention, FIG. 2 is a block diagram of control of the present embodiment, and FIG. 3 is a constant discharge pressure control of the first embodiment. Fig. 4 is an operating characteristic diagram of the system, and Fig. 4 is an operating characteristic diagram of the terminal pressure constant control showing the second embodiment. FIG. 5 is a system diagram of a conventional water supply device, FIG. 6 is an operation characteristic diagram of a constant discharge pressure control system,
FIG. 7 is an operating characteristic diagram of the constant end pressure control method. 4 ... Variable speed pump 6 ... Water supply pipe 7 ... Pressure sensor 8 ... Flow rate sensor 9a, 9b, 9c ... Water supply equipment Sa, Sb, Sc ... Sensor CTL ... Control device

Claims (1)

[Claims] 1. A variable speed pump, a control device for controlling the speed of the variable speed pump, a water supply pipe arranged on the discharge side of the variable speed pump, and a faucet provided at the end of the water supply pipe. And a pressure sensor provided on the water supply pipe to detect the water pressure of the water supply pipe and output the water pressure to the control device, and the pressure detected by the pressure sensor becomes a target pressure on the discharge side of the pump stored in advance. In the operating device of the variable speed pump, which controls the speed of the variable speed pump, the open state of the water faucet is detected and a predetermined installation zone corresponding to the installation height of the water faucet in the building is corresponded. A detection means for emitting a signal, the control device, a storage means for storing a plurality of target pressure changed according to the installation zone, and a signal corresponding to the installation zone from the detection means to the storage means. Memory A plurality of target pressures selected based on the received zone-corresponding signal received, the control device is configured to control the speed of the pump according to the selected target pressures. A variable speed pump operating device characterized in that