JP2009030821A - Water supply control system and water supply control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform end differential pressure control for performing pressure control by an invertor pump on the basis of end differential pressure even if a pipe end cannot be specified. <P>SOLUTION: This water supply control system comprises differential pressure measuring means mounted to valves 6-1 to 6-3 disposed at inlets of a plurality of load apparatuses 5-1 to 5-3 and measuring differential pressure between supply water at the inlet of each of the plurality of load apparatuses 5-1 to 5-3 and return water at the outlet of each of the plurality of load apparatuses 5-1 to 5-3, and the water supply control device 12 comparing the plurality of differential pressure measured by the differential pressure measuring means, specifying the end differential pressure of the pipe end, and controlling rotational speeds of pumps 9-1, 9-2 and an opening of a bypass valve 10 based on the end differentioal pressure. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a water supply control system and a water supply control method for controlling a pump or the like that sends cold / hot water generated by a heat source device to a load device.

  Conventionally, in air-conditioning control systems, etc., when energy saving is achieved by an inverter of a pump that conveys a heat medium such as cold water or hot water, a pressure transmitter is installed at the end of the pipe, and the water supply pressure is set based on the differential pressure at the end And the inverter rotation speed of the pump and the opening degree of the bypass valve were controlled based on the set water supply pressure (see, for example, Patent Document 1). FIG. 9 is a block diagram showing a configuration of a conventional air conditioning control system disclosed in Patent Document 1. In FIG.

  The air conditioning control system in FIG. 9 includes heat source devices 21-1 to 21-3 that generate a heat medium such as cold water and hot water, and primary pumps 22-1 to 22-1 as auxiliary devices of the heat source devices 21-1 to 21-3. 22-3, forward headers 23-1, 23-2 for mixing the heat medium from the plurality of heat source devices 21-1 to 21-3, water supply conduit 24, and load devices such as a fan coil unit and an air conditioner 25-1 to 25-3, a differential pressure sensor 26 for measuring the terminal differential pressure P2, a return water pipe 27, and heat exchange in the load devices 25-1 to 25-3 and sent via the return water pipe 27. Return path header 28 to which the incoming heat medium is returned, secondary pumps 29-1 to 29-3 provided between forward headers 23-1 and 23-2, and forward headers 23-1 and 23-2 A bypass valve 30 provided therebetween, a pressure sensor 31 for measuring the water supply pressure P1, Composed of water control device 32 for controlling the pump 29-1～29-3 like for delivering medium to the load device 25-1 to 25-3. The secondary pumps 29-1 and 29-2 include inverters 29-1a and 29-2a, respectively.

  Heat medium (water supply) such as cold water or hot water pressure-fed by the primary pumps 22-1 to 22-3 and heated by the heat source devices 21-1 to 21-3 is sent to the forward header 23-1, Pumped by the pumps 29-1 to 29-3, supplied to the water supply pipe 24 through the forward header 23-2, passed through the load devices 25-1 to 25-3, and returned as return water by the return water pipe 27. It reaches the header 28 and is again pumped by the pumps 22-1 to 22-3. Thus, the heat medium circulates through the above path.

  In the air conditioning control system as shown in FIG. 9, the pressure sensor 31 measures the water supply pressure P1. The differential pressure sensor 26 supplies water to the load device 25-3 and the load device 25-, which are provided at the end of the pipe, that is, the extreme end on the side where the water is output from the water supply pipe 24 (load device side). The terminal differential pressure P2 which is a pressure difference with the return water output from 3 is measured. And the water supply control apparatus 32 sets water supply pressure based on the terminal differential pressure P2, and based on this water supply pressure setting value, the inverter rotational speed of the secondary pumps 9-1 and 9-2 and the opening degree of the bypass valve 30 Was controlling.

JP 2005-299980 A

According to the system shown in FIG. 9, the energy required for the pump head can be reduced, and energy saving can be realized.
However, when the system shown in FIG. 9 is introduced, it is necessary to specify the end of the pipe and install a differential pressure sensor at this end, but it is difficult to specify the end of the pipe. Since the installation of the differential pressure sensor is difficult, there is a problem that the introduction of the system is often abandoned.

  The present invention has been made to solve the above-described problem, and even when the end of the pipe cannot be specified when the differential pressure sensor is installed, the end differential pressure control in which the pressure control by the inverter pump is performed based on the end differential pressure can be realized. An object is to provide a water supply control system and a water supply control method capable of realizing energy saving.

In the water supply control system of the present invention, a pump for sending water supplied with pressure to return water from a plurality of load devices to the load device, an input side of the pump to which the return water is input, and the water supply are output. A bypass valve provided in a bypass connecting the output side of the pump and a valve disposed at an inlet of the plurality of load devices, and the water supply at the inlet of the load device and the load device By comparing the plurality of first differential pressure measuring means for measuring the differential pressure with the return water at the outlet and the plurality of differential pressures measured by the first differential pressure measuring means, the terminal differential pressure at the end of the pipe And a control means for controlling the rotational speed of the pump and the opening of the bypass valve based on the terminal differential pressure.
Moreover, one structural example of the water supply control system of this invention is further provided with the water supply pressure measurement means which measures the pressure of the said water supply in the exit of the said pump, The said control means of the said pump based on the said terminal differential pressure | voltage The water supply pressure at the outlet is set, and the rotational speed of the pump and the opening of the bypass valve are controlled based on the set value and the water supply pressure measured by the water supply pressure measuring means.
Further, one configuration example of the water supply control system of the present invention further includes second differential pressure measuring means for measuring a differential pressure between the water supply at the outlet of the pump and the return water at the inlet of the pump, The control means sets a differential pressure between the water supply at the outlet of the pump and the return water at the inlet of the pump based on the terminal differential pressure, and is measured by the set value and the second differential pressure measuring means. The rotational speed of the pump and the opening of the bypass valve are controlled based on the differential pressure.

  The present invention also relates to a heat source device that generates cold / hot water, a pump that supplies water to which pressure is added to return water from a plurality of load devices, and an input to the pump to which the return water is input. In the water supply control system comprising a bypass valve provided in a bypass that connects the output side of the pump to which the water supply is output, the water supply that sends the cold / hot water generated by the heat source device to the load device A control method, comprising: a differential pressure measuring procedure for measuring a differential pressure between the water supply at the inlet of the load device and the return water at the outlet of the load device in a valve provided in each of the plurality of load devices; , Comparing a plurality of differential pressures measured in this differential pressure measurement procedure, specifying a terminal differential pressure at the end of the pipe, and based on the terminal differential pressure, the pump rotation speed and the Vipa In which a control procedure for controlling the opening of the valve.

  According to the present invention, each of the valves provided in the plurality of load devices is provided with a plurality of first differential pressure measuring means for measuring a differential pressure between water supply at the inlet of the load device and return water at the outlet of the load device. Since the terminal differential pressure is specified by comparing the plurality of differential pressures measured by the first differential pressure measuring means, the inverter pump and the pump can be specified even when the pipe terminal cannot be specified when the differential pressure measuring means is installed. It is possible to realize the terminal differential pressure control in which the pressure control by the bypass valve is performed based on the terminal differential pressure, and energy saving can be realized.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an air conditioning control system according to the first embodiment of the present invention. In the present embodiment, a dual pump system is used as a water supply system to load equipment.

  The air conditioning control system of the present embodiment generates a heat medium such as cold water and hot water, and heat source devices 1-1 to 1-3 such as a cold / hot water generator, a heat pump, a refrigerator, and a boiler, and the heat source device 1- Primary pumps 2-1 to 2-3 as auxiliary machines 1-1 to 1-3, forward headers 3-1 and 3-2 for mixing the heat medium from the plurality of heat source apparatuses 1-1 to 1-3, Water supply conduit 4, load devices 5-1 to 5-3 such as a fan coil unit and an air conditioner, and valves 6-1 to control the flow rate of the heat medium supplied to the load devices 5-1 to 5-3 6-3, return water pipe 7, return path header 8 to which heat medium exchanged in the load devices 5-1 to 5-3 and sent via the return water pipe 7 is returned, and forward path header 3- Secondary pumps 9-1 to 9-3 provided between 1 and 3-2 and bypass valves provided between forward headers 3-1 and 3-2 0, a pressure sensor (water supply pressure measuring means) 11 for measuring the water supply pressure P1, a water supply control device for controlling the pumps 9-1 to 9-3 for sending the heat medium to the load devices 5-1 to 5-3, etc. 12 and a load device control device 13 that controls the supply amount of the heat medium to the load devices 5-1 to 5-3 by adjusting the opening degree of the valves 6-1 to 6-3. The secondary pumps 9-1 and 9-2 include inverters 9-1a and 9-2a, respectively.

  Among these air conditioning control systems, heat source devices 1-1 to 1-3, primary pumps 2-1 to 2-3, forward headers 3-1 and 3-2, water supply pipeline 4, return water pipeline 7 and return header 8, the secondary pumps 9-1 to 9-3, the bypass valve 10, the pressure sensor 11, and the water supply control device 12 constitute a water supply control system.

  A heat medium (water supply) such as cold water or hot water pressure-fed by the primary pumps 2-1 to 2-3 and heated by the heat source units 1-1 to 1-3 is sent to the forward header 3-1, Pumped by the pumps 9-1 to 9-3, supplied to the water supply pipe 4 through the forward header 3-2, passed through the load devices 5-1 to 5-3, and returned as return water by the return water pipe 7. It reaches the header 8 and is again pumped by the pumps 2-1 to 2-3. Thus, the heat medium circulates through the above path.

The water supply pressure P1 means the pressure of water supplied by the secondary pumps 9-1 to 9-3 or the like and sent to the water supply pipeline 4.
Moreover, the terminal differential pressure P2 is the load provided at the end of the building where the air conditioning control system of FIG. 1 is provided, that is, the extreme end on the side where the water supply is output from the water supply conduit 4 (load device side). It means the pressure difference between the water input to the device and the return water output from this load device. Here, the pipe end means a portion having the largest pipe resistance as viewed from the pump, but it is difficult to specify the actual pipe end for the following reason.

  Although it is possible to specify the end of the pipe from the theory (on the drawing), the maximum pipe resistance value after actual pipe construction may not necessarily be the longest pipe length, and manual Since there are some uncertain factors such as the location that is throttled by the valve, it is difficult to accurately identify the actual pipe end. In general, since a plurality of pipes start from the header, the capacity of all the air conditioners cannot be guaranteed unless at least the part having the largest pipe resistance is specified for each system.

  Therefore, in the present embodiment, in order to perform the control safely (that is, to prevent the air conditioner from being insufficient in capacity), a plurality of valves 6-1 installed at locations assumed to be the end of the pipe. ˜6-3 was provided with a differential pressure sensor (differential pressure measuring means) for measuring the pressure difference between the water supply and the return water. In this manner, by installing the differential pressure sensor in the valves 6-1 to 6-3, it is not necessary to install the differential pressure sensor at the end of the pipe.

  FIG. 2 is a block diagram illustrating a configuration example of the water supply control device 12. The water supply control device 12 performs load device control on the water pressure receiving unit 120 that receives the value of the water pressure P1 measured by the pressure sensor 11 and the value of the differential pressure measured by the differential pressure sensors of the valves 6-1 to 6-3. The differential pressure receiving unit 121 received via the device 13, the setting unit 122 that sets the terminal differential pressure setting value P2set by the user's operation input, etc., and a plurality of differential pressures received by the differential pressure receiving unit 121 are compared. The terminal differential pressure specifying unit 123 that specifies the terminal differential pressure P2, the water supply pressure P1 received by the water supply pressure receiving unit 120, the terminal differential pressure P2 specified by the terminal differential pressure specifying unit 123, and the terminal difference set by the setting unit 122 Based on the pressure set value P2set, a calculation unit 124 that calculates the inverter rotation speed of the secondary pumps 9-1 and 9-2 and the opening of the bypass valve 10, and inverters 9-1a and 9 based on the calculation result of the calculation unit 124 -2a A pump control unit 125 that controls the rotation speed of the secondary pumps 9-1 and 9-2 (hereinafter referred to as inverter rotation speed), and a bypass that controls the opening degree of the bypass valve 10 based on the calculation result of the calculation unit 124. And a valve control unit 126.

The calculation unit 124, the pump control unit 125, and the bypass valve control unit 126 constitute a control unit.
The pump control unit 125 performs operation control related to ON / OFF of the secondary pump 9-3 based on the operation input by the user via the setting unit 122 or the calculation result of the calculation unit 124. In addition, the pump control unit 125 transmits information related to the operation status of the secondary pumps 9-1 to 9-3 to the calculation unit 124.

  Next, the operation of the present embodiment will be described with reference to FIGS. FIG. 3 is a flowchart showing the operation of the water supply control device 12, FIG. 4 is a diagram for explaining the relationship between the water supply pressure and the terminal differential pressure, and FIG. 5 is for explaining the relationship between the inverter rotational speed and the bypass valve opening and the water supply pressure. FIG.

  First, the operation of the load device control device 13 will be described by taking the case where the load devices 5-1 to 5-3 are air conditioners as an example. The load devices 5-1 to 5-3 receive the supply of the heat medium from the heat source devices 1-1 to 1-3, and cool the mixture of the air (return air) returning from the room serving as the air conditioning control area and the outside air. Alternatively, the heated and cooled or heated supply air is sent into the room by a blower. The load device control device 13 calculates an operation amount by, for example, PID calculation so that the temperature of the supply air sent from the load devices 5-1 to 5-3 matches the set temperature, and the calculated operation amount is set to the valve. Output to 6-1 to 6-3 to control the opening degree of the valves 6-1 to 6-3.

Thus, while the air conditioning control as described above is performed on the load device side, the following water supply control is performed on the heat source device side.
First, the differential pressure sensor built in the valve 6-1 measures the differential pressure between the water sent to the load device 5-1 and the return water from the load device 5-1. Similarly, the differential pressure sensor built in the valves 6-2 and 6-3 is a difference between the water sent to the load devices 5-1 and 5-2 and the return water from the load devices 5-1 and 5-2. Measure the pressure.

  A differential pressure signal indicating the differential pressure measured by these differential pressure sensors is sent to the load device control device 13. The load device control device 13 and the water supply control device 12 are connected by a communication line such as wired or wireless. The load device control device 13 transmits the differential pressure signal to the water supply control device 12 via the communication line.

The differential pressure receiving unit 121 of the water supply control device 12 receives the differential pressure signal transmitted from the load device control device 13 (step S1 in FIG. 3).
On the other hand, the water supply pressure receiving unit 120 receives a water supply pressure signal indicating the value of the water supply pressure P1 measured by the pressure sensor 11 (step S2).

  The terminal differential pressure specifying unit 123 compares a plurality of differential pressure values indicated by the differential pressure signal received by the differential pressure receiving unit 121, and sets the worst value of these differential pressures as the terminal differential pressure P2 (step S3). . Here, the minimum value among the plurality of differential pressures is defined as the worst value.

  Next, as shown in FIG. 4, the calculation unit 124 sets the water supply pressure by PID control based on the terminal differential pressure setting value P2set preset by the user or the like (step S4). When the terminal differential pressure P2 specified by the terminal differential pressure specifying unit 123 is smaller than the terminal differential pressure set value P2set, the calculation unit 124 sets the water supply pressure to be large by the P operation (proportional operation). Further, when the terminal differential pressure P2 is larger than the terminal differential pressure set value P2set, the calculation unit 124 sets the water supply pressure to be small by the P operation.

  For example, in FIG. 4, when the terminal differential pressure P2 is the terminal differential pressure P2a smaller than the terminal differential pressure set value P2set, the terminal differential pressure P2a increases as the water supply pressure increases. The water supply pressure a is set higher than the water supply pressure x corresponding to the differential pressure set value P2set. In FIG. 4, when the terminal differential pressure P2 is the terminal differential pressure P2a larger than the terminal differential pressure set value P2set, the terminal differential pressure P2a increases as the water supply pressure increases. A water supply pressure b smaller than the water supply pressure x corresponding to the differential pressure set value P2set is set.

  Further, since the deviation is eliminated by the I operation (integration operation), when the current terminal differential pressure P2 is smaller than the terminal differential pressure set value P2set, the water supply pressure set value P1set is further increased, and the current terminal differential pressure P2 becomes the terminal differential. When it is larger than the pressure set value P2set, the water supply pressure set value P1set is further reduced.

  Subsequently, the calculation unit 124 determines the inverter rotational speed of the secondary pumps 9-1 and 9-2 and the opening degree of the bypass valve 10 based on the water supply pressure set value P1set set in step S4 (step S5). . The calculation unit 124 increases the inverter rotation speed when the water supply pressure P1 measured by the pressure sensor 11 is smaller than the water supply pressure set value P1set, and the inverter rotation speed when the water supply pressure P1 is larger than the water supply pressure set value P1set. Make it smaller. Thus, the inverter rotational speed is determined so that the water supply pressure P1 matches the water supply pressure set value P1set. In addition, the calculation unit 124, when the water supply pressure P1 is considerably larger than the water supply pressure set value P1set and the water supply pressure P1 cannot be matched with the water supply pressure set value P1set even if the inverter rotation speed is set to the lower limit value, The opening degree is determined so that the bypass valve 10 is opened according to the level of the water supply pressure P1.

  In FIG. 5, I1 and I2 are characteristics indicating the relationship between the inverter rotational speed and the water supply pressure, and B is a characteristic indicating the relationship between the bypass valve opening and the water supply pressure. The relationship between the inverter rotational speed and the water supply pressure is as follows: when the pump is operated alone by the pump with the inverter (secondary pumps 9-1 and 9-2 in this embodiment), and when the pump with the inverter is not connected to the inverter. The lower limit value of the inverter rotation speed is switched, which is different in the pump parallel operation in which the installed pump (secondary pump 9-3 in the present embodiment) is operating simultaneously. I1 is a characteristic at the time of pump independent operation, and I2 is a characteristic at the time of pump parallel operation.

  For example, in FIG. 5, when the water supply pressure P1 measured by the pressure sensor 11 is a water supply pressure P1a smaller than the water supply pressure set value P1set, the water supply pressure increases as the inverter rotational speed is increased. The inverter speed a is set higher than the water supply pressure y corresponding to the set value P1set. Further, in FIG. 5, when the water supply pressure P1 is a water supply pressure P1b larger than the water supply pressure set value P1set, the water supply pressure becomes smaller if the inverter rotation speed is lowered. Therefore, the water supply pressure corresponding to the water supply pressure set value P1set is reduced. The inverter speed b is set lower than the pressure y. Furthermore, in FIG. 5, when the water supply pressure P1 is a water supply pressure P1c that is larger than the water supply pressure set value P1set, the inverter rotational speed has already reached the lower limit value. Lower. Therefore, the opening degree of the bypass valve 10 is set to the opening degree c as shown in FIG.

  As described above, the lower limit value of the inverter rotational speed is switched depending on the operation status of the secondary pumps 9-1 to 9-3. The lower limit value is switched by the calculation unit 124 based on the operation status of the secondary pump 9-3 without an inverter.

The pump control unit 125 controls the inverter rotation speed of the secondary pumps 9-1 and 9-2 via the inverters 9-1a and 9-2a based on the determination of the calculation unit 124. In addition, when the secondary pump 9-3 without an inverter operates, the water supply pressure of the pump 9-3 is always set to the rated value (maximum value).
The bypass valve control unit 126 controls the opening degree of the bypass valve 10 based on the determination of the calculation unit 124.

The process shown in FIG. 3 as described above is repeated until the system stops operating (YES in step S6 in FIG. 3).
Thus, in the present embodiment, a differential pressure sensor is provided for each of the plurality of valves 6-1 to 6-3 installed at locations assumed to be the ends of the pipes, and a plurality of the differential pressure sensors measured by the differential pressure sensors are provided. Since the terminal differential pressure P2 is specified by comparing the differential pressure, information of the terminal differential pressure P2 can be acquired even when the pipe terminal cannot be specified at the time of installing the differential pressure sensor. Further, in the present embodiment, by incorporating the differential pressure sensor in the valves 6-1 to 6-3, it is not necessary to specify the end of the pipe and install the differential pressure sensor at the end of the pipe.

  In the present embodiment, the water supply pressure is set based on the terminal differential pressure P2, and the inverter rotational speeds of the secondary pumps 9-1 and 9-2 and the opening degree of the bypass valve 10 are set based on the set water supply pressure. By controlling the above, energy saving can be realized. That is, in this embodiment, since the water supply pressure is changed according to the terminal differential pressure P2, the water supply pressure can be reduced when the flow rate is small. Therefore, the energy required for the pump head can be reduced, and as a result, further energy saving can be realized.

  Moreover, in this Embodiment, the load equipment control apparatus 13 is provided in the vicinity of the load equipment 5-1 to 5-3, and the water supply control apparatus 12 is provided in the vicinity of the secondary pumps 9-1 to 9-3. Since the load device control device 13 and the water supply control device 12 are connected by a communication line such as wired or wireless, there is no need for large-scale wiring construction from the end of the pipe to the machine room where the pump power panel is installed. Wiring construction can be facilitated.

  Further, in the present embodiment, the inverter rotational speed of the secondary pumps 9-1 and 9-2 and the opening degree of the bypass valve 10 are set based on the water supply pressure P1, but between the headers (in FIG. 1) The inverter rotation speed and the opening degree of the bypass valve 10 may be set based on the pressure difference between the header 3-1 and the header 3-2.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 6 is a block diagram showing a configuration of an air conditioning control system according to the second embodiment of the present invention, and the same reference numerals are given to the same configurations as those in FIG. In the present embodiment, a single pump system is used as a water supply system to load equipment.

The air conditioning control system of the present embodiment mixes heat source devices 1-1 to 1-3, primary pumps 2-1 to 2-3, and heat media from a plurality of heat source devices 1-1 to 1-3. Outbound header 3, water supply conduit 4, load devices 5-1 to 5-3, valves 6-1 to 6-3, return water conduit 7, return conduit header 8, and heat medium as load device 5 The differential pressure between the water supply control device 12a for controlling the pumps 2-1 to 2-3 to be sent to -1 to 5-3, the load device control device 13, and the forward header 3 and the return header 8 is measured. Differential pressure gauge (differential pressure measuring means) 14 and a bypass valve 15 provided between the forward header 3 and the return header 8.
Among these air conditioning control systems, the heat source devices 1-1 to 1-3, the primary pumps 2-1 to 2-3, the forward header 3, the water supply pipeline 4, the return water pipeline 7, the return route header 8, and the water supply control device 12a. The differential pressure gauge 14 and the bypass valve 15 constitute a water supply control system.

  Heat medium (water supply) such as cold water or hot water pressure-fed by the primary pumps 2-1 to 2-3 and heated by the heat source units 1-1 to 1-3 is supplied to the water supply pipeline 4 via the forward header 3. Then, it passes through the load devices 5-1 to 5-3, reaches the return path header 8 as return water by the return water pipeline 7, and is again pumped by the pumps 2-1 to 2-3. Thus, the heat medium circulates through the above path. Here, the primary pumps 2-1 and 2-2 include inverters 2-1a and 2-2a, respectively.

  In the present embodiment, the header differential pressure is set based on the terminal differential pressure P2, and the primary pumps 2-1 and 2-2 are connected via the inverters 2-1a and 2-2a based on the set header differential pressure. The inverter rotation speed and the opening degree of the bypass valve 15 are controlled. Here, the inter-header differential pressure is the differential pressure between the forward header 3 and the return header 8, that is, the water sent from the forward header 3 to the water supply pipeline 4 and the return water pipeline 7 to the return header 8. It means the pressure difference with the returned water being sent out.

  FIG. 7 is a block diagram showing a configuration example of the water supply control device 12a, and the same reference numerals are given to the same configurations as those in FIG. The water supply control device 12 includes a differential pressure receiving unit 121, a setting unit 122, a terminal differential pressure specifying unit 123, a header differential pressure measured by the differential pressure gauge 14, and a terminal differential pressure specifying unit 123 specified by the terminal differential pressure P2. And a calculation unit 124a for calculating the inverter rotational speed of the secondary pumps 9-1 and 9-2 and the opening degree of the bypass valve 10 based on the terminal differential pressure setting value P2set set by the setting unit 122, and the calculation unit 124a A pump control unit 125a that controls the rotation speeds of the primary pumps 2-1 and 2-2 (hereinafter referred to as inverter rotation speeds) via the inverters 2-1a and 2-2a based on the calculation results, and the calculation results of the calculation unit 124a The bypass valve control unit 126a that controls the opening degree of the bypass valve 15 based on the above, and the differential pressure receiving unit 127 that receives the value of the inter-header differential pressure DP measured by the differential pressure gauge 14.

Next, the operation of the present embodiment will be described with reference to FIG. FIG. 8 is a flowchart showing the operation of the water supply control device 12a.
The operations of the load devices 5-1 to 5-3, the valves 6-1 to 6-3, and the load device control device 13 are the same as those in the first embodiment.

The differential pressure receiving unit 121 of the water supply control device 12a receives the differential pressure signal transmitted from the load device control device 13 (step S11 in FIG. 8).
On the other hand, the differential pressure receiving unit 127 receives an inter-header differential pressure signal indicating the value of the inter-header differential pressure DP measured by the differential pressure gauge 14 (step S12).

The terminal differential pressure specifying unit 123 specifies the terminal differential pressure P2 as in the first embodiment (step S13).
Next, the calculation unit 124a sets the inter-header differential pressure by PID control based on the terminal differential pressure setting value P2set preset by the user or the like (step S14). Subsequently, the calculation unit 124a determines the inverter speed of the primary pumps 2-1 and 2-2 and the opening degree of the bypass valve 15 based on the header differential pressure setting value DPset set in step S14 (step S15). ). Thus, the inverter rotational speed and the bypass valve opening are determined so that the inter-header differential pressure DP measured by the differential pressure gauge 14 matches the inter-header differential pressure setting value DPset.

The pump control unit 125a controls the inverter rotation speed of the primary pumps 2-1 and 2-2 via the inverters 2-1a and 2-2a based on the determination of the calculation unit 124a. In addition, when the primary pump 2-3 without an inverter operates, the water supply pressure of the pump 2-3 is always set to a rated value (maximum value).
The bypass valve control unit 126a controls the opening degree of the bypass valve 15 based on the determination of the calculation unit 124a.

The process shown in FIG. 8 as described above is repeated until the system stops operating (YES in step S16 in FIG. 8).
Thus, also in this embodiment, the same effect as that of the first embodiment can be obtained.

  Further, the water supply control devices 12 and 12a and the load device control device 13 described in the first and second embodiments are respectively a computer having a CPU, a storage device and an interface, and a program for controlling these hardware resources. Can be realized. The CPUs of these computers execute the processes described in the first and second embodiments in accordance with programs stored in the storage device.

  The present invention can be applied to a water supply control system that sends cold / hot water generated by a heat source machine to a load device.

It is a block diagram which shows the structure of the air-conditioning control system which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the water supply control apparatus of the air-conditioning control system of FIG. It is a flowchart which shows operation | movement of the water supply control apparatus of FIG. It is a figure explaining the relationship between water supply pressure and terminal differential pressure. It is a figure explaining the relationship between an inverter rotation speed, a bypass valve opening degree, and water supply pressure. It is a block diagram which shows the structure of the air-conditioning control system which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structural example of the water supply control apparatus of the air-conditioning control system of FIG. It is a flowchart which shows operation | movement of the water supply control apparatus of FIG. It is a block diagram which shows the structure of the conventional air conditioning control system.

Explanation of symbols

  1-1 to 1-3 ... heat source machine, 2-1 to 2-3 ... primary pump, 2-1a to 2-2a ... inverter, 3, 3-1, 3-2 ... forward header, 4 ... water supply pipeline 5-1 to 5-3 ... load equipment, 6-1 to 6-3 ... valve, 7 ... return water pipe, 8 ... return path header, 9-1 to 9-3 ... secondary pump, 9-1a, 9-2a ... Inverter 10, 15 ... Bypass valve, 11 ... Pressure sensor, 12, 12a ... Water supply control device, 13 ... Load device control device, 14 ... Differential pressure gauge, 120 ... Water supply pressure receiving unit, 121 ... Differential pressure reception , 122 ... setting unit, 123 ... terminal differential pressure specifying unit, 124, 124a ... calculation unit, 125, 125a ... pump control unit, 126, 126a ... bypass valve control unit, 127 ... differential pressure receiving unit.

Claims (4)

In a water supply control system that sends cold / hot water generated by a heat source machine to load equipment,
A pump for sending water to which the pressure is applied to the return water from a plurality of load devices to the load device;
A bypass valve provided in a bypass connecting the input side of the pump to which the return water is input and the output side of the pump from which the water supply is output;
A plurality of first differential pressures that are provided in each of the valves disposed at the inlets of the plurality of load devices, and that measure a differential pressure between the water supply at the inlet of the load device and the return water at the outlet of the load device. Measuring means;
A terminal differential pressure specifying means for comparing a plurality of differential pressures measured by the first differential pressure measuring means and specifying a terminal differential pressure at a pipe end; and
A water supply control system comprising: control means for controlling the rotational speed of the pump and the opening of the bypass valve based on the terminal differential pressure. In the water supply control system according to claim 1,
Furthermore, it comprises a water supply pressure measuring means for measuring the pressure of the water supply at the outlet of the pump,
The control means sets the water supply pressure at the outlet of the pump based on the terminal differential pressure, and based on the set value and the water supply pressure measured by the water supply pressure measurement means, the rotation speed of the pump and the A water supply control system that controls the opening degree of a bypass valve. In the water supply control system according to claim 1,
And a second differential pressure measuring means for measuring a differential pressure between the water supply at the outlet of the pump and the return water at the inlet of the pump,
The control means sets a differential pressure between the water supply at the outlet of the pump and the return water at the inlet of the pump based on the terminal differential pressure, and is measured by the set value and the second differential pressure measuring means. A water supply control system that controls the rotation speed of the pump and the opening of the bypass valve based on the differential pressure that is generated. A heat source device for generating cold / hot water, a pump for sending water to which the pressure is added to the return water from a plurality of load devices, the input side of the pump to which the return water is input, and the water output is output In a water supply control system comprising a bypass valve provided in a bypass that connects the output side of the pump, a water supply control method for sending cold / warm water generated by the heat source device to the load device,
In a valve provided in each of the plurality of load devices, a differential pressure measurement procedure for measuring a differential pressure between the water supply at the inlet of the load device and the return water at the outlet of the load device;
Comparing a plurality of differential pressures measured in this differential pressure measurement procedure, a terminal differential pressure specifying procedure for specifying the terminal differential pressure at the end of the pipe,
A water supply control method comprising: a control procedure for controlling the rotational speed of the pump and the opening of the bypass valve based on the terminal differential pressure.

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