US20160341440A1 - Method for controlling number of pumps, device for controlling number of pumps, pump system, heat source system, and program - Google Patents

Method for controlling number of pumps, device for controlling number of pumps, pump system, heat source system, and program Download PDF

Info

Publication number
US20160341440A1
US20160341440A1 US15/111,025 US201415111025A US2016341440A1 US 20160341440 A1 US20160341440 A1 US 20160341440A1 US 201415111025 A US201415111025 A US 201415111025A US 2016341440 A1 US2016341440 A1 US 2016341440A1
Authority
US
United States
Prior art keywords
pumps
pump
flow rate
operating
threshold value
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US15/111,025
Other languages
English (en)
Inventor
Toshiaki Ouchi
Satoshi Nikaido
Minoru Matsuo
Koki Tateishi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Thermal Systems Ltd
Original Assignee
Mitsubishi Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Assigned to MITSUBISHI HEAVY INDUSTRIES, LTD. reassignment MITSUBISHI HEAVY INDUSTRIES, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MATSUO, MINORU, NIKAIDO, Satoshi, OUCHI, TOSHIAKI, TATEISHI, Koki
Publication of US20160341440A1 publication Critical patent/US20160341440A1/en
Assigned to MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD. reassignment MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MITSUBISHI HEAVY INDUSTRIES, LTD.
Abandoned legal-status Critical Current

Links

Images

Classifications

    • F24F11/06—
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
    • F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
    • F24F11/85—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers using variable-flow pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B41/00—Pumping installations or systems specially adapted for elastic fluids
    • F04B41/06—Combinations of two or more pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/02—Stopping, starting, unloading or idling control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/06—Control using electricity
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/06—Control using electricity
    • F04B49/065—Control using electricity and making use of computers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
    • F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B25/00—Machines, plants or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00
    • F25B25/005—Machines, plants or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00 using primary and secondary systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2207/00—External parameters
    • F04B2207/04—Settings
    • F04B2207/041—Settings of flow
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/13—Pump speed control
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Definitions

  • the present invention relates to a method for controlling number of pumps, a device for controlling number of pumps, a pump system, a heat source system, and a program.
  • a heat source system that supplies a heat medium such as cold water or hot water (hereinafter, “cold/hot water”) from a heat source machine to a load device such as an air conditioner
  • a plurality of secondary pumps that are connected in parallel between the heat source machine and the air conditioner are often installed to forcibly feed the heat medium to the air conditioner apart from the heat source machine again in addition to a primary pump that forcibly feeds the cold/hot water to the heat source machine.
  • a technique of deciding the number of secondary pumps that are operated so that a discharge flow rate to the load device is satisfied is used.
  • a threshold value serving as a reference for increasing or decreasing the number of pumps is set, and control is often performed such that an additional pump is started when the flow rate of the heat medium measured by measuring equipment installed in the middle of a supply path exceeds the threshold value thereof, whereas when the measured flow rate of the heat medium is the threshold value or less, a pump is stopped.
  • the number of operating pumps is increased or decreased based on only the measured flow rate, it is likely for an additional pump to be started even when there is still room in the capability of the pumps, that is, the frequency of the pumps is enough compared to the rated frequency.
  • Patent Literature 1 by changing the number of operating pumps using a flow rate as a threshold value which is decided at a crossing point between a curved line indicating a relation of a pump discharge pressure and a pump discharge flow rate which are decided for each of the number of operating secondary pumps and a control line indicating a correlation of a flow rate of a heat medium to be supplied to a load device and a pump discharge pressure necessary for it, the threshold value of the flow rate at which discharge pressure can be maintained even after the number of pumps is changed is set.
  • the pressure drop of the pipe refers to loss of pump discharge pressure caused by friction occurring when a heat medium flows in a pipe, a curved pipe, resistance by a valve, or the like, and the pressure drop characteristic is a change characteristic of the pressure drop to the flow rate of the heat medium.
  • the load device is an air conditioner
  • a pressure drop of a system is changed by a control valve with which the air conditioner is equipped, and thus a threshold value used for control of the number of operating pumps undergoes deviation unless a change in the control line is additionally considered. If the number of operating pumps is not changed at an appropriate timing, for example, the flow rate or the pressure of the heat medium changes due to the unnecessary change in the number of pumps, and it is hard to operate the heat source system stably.
  • the present invention provides a method for controlling number of pumps, a device for controlling number of pumps, a pump system, a heat source system, and a program.
  • a method for controlling number of pumps includes a process of increasing or decreasing a number of operating pumps based on a flow rate of a heat medium that is forcibly fed to a load by a plurality of pumps connected in parallel or a heat load required by the load and a frequency command value commanded to each pump in operation among the plurality of pumps.
  • the method for controlling number of pumps according to the first aspect further includes a process of acquiring a number-of-pumps determination flow rate value indicating the flow rate of the heat medium forcibly fed to the load from a measurement value of a discharge flow rate by the pumps in operation among the plurality of pumps, wherein, in the process of increasing or decreasing the number of operating pumps, the number of operating pumps is increased when the number-of-pumps determination flow rate value is equal to or larger than a predetermined threshold value G ⁇ , and the frequency command value commanded to each pump is equal to or larger than a predetermined threshold value F ⁇ , and the number of operating pumps is decreased when the number-of-pumps determination flow rate value is equal to or smaller than a predetermined threshold value G ⁇ , and the frequency command value commanded to each pump is equal to or smaller than a predetermined threshold value F ⁇ .
  • the method for controlling number of pumps according to the first aspect further includes a process of calculating the heat load required by the load, wherein, in the process of increasing or decreasing the number of operating pumps, the number of operating pumps is increased when the heat load is equal to or larger than a predetermined threshold value L ⁇ , and the frequency command value commanded to each pump is equal to or larger than a predetermined threshold value F ⁇ , and the number of operating pumps is decreased when the heat load is equal to or smaller than a predetermined threshold value L ⁇ , and the frequency command value commanded to each pump is equal to or smaller than a predetermined threshold value F ⁇ .
  • a pump head of the pump in the process of increasing or decreasing the number of operating pumps, is further compared with an increase permission pump head serving as a threshold value for increasing the number of pumps or a decrease permission pump head serving as a threshold value for decreasing the number of pumps, the number of operating pumps is increased only when the increase permission pump head is smaller than the pump head, and the number of operating pumps is decreased only when the decrease permission pump head is larger than the pump head.
  • the method for controlling number of pumps according to the fourth aspect further includes a process of obtaining the increase permission pump head by calculating the pump head when a frequency of the pump is operated at the predetermined threshold value F ⁇ from the pump head calculated based on the discharge flow rate of the pump after the number of operating pumps is increased and a predetermined correlation of the pump head for the discharge flow rate of the pump and obtaining the decrease permission pump head by calculating the pump head when the frequency of the pump is operated at the predetermined threshold value F ⁇ from the pump head calculated based on the discharge flow rate of the pump after the number of operating pumps is decreased and the predetermined correlation.
  • the method for controlling number of pumps according to the second or third aspect further includes a process of acquiring a frequency command value after the number of operating pumps is increased and a frequency command value after the number of operating pumps is decreased based on a predetermined correlation between the pump head and the discharge flow rate of the pump at a predetermined frequency of the pump in operation under a condition that the pump head after the number of operating pumps is increased or decreased to be equal to a current pump head, wherein, in the process of increasing or decreasing the number of operating pumps, the number of operating pumps is further increased only when the frequency command value after the number of operating pumps is increased is larger than the threshold value F ⁇ , and the number of operating pumps is decreased only when the frequency command value after the number of operating pumps is decreased is smaller than the threshold value F ⁇ .
  • the method for controlling number of pumps according to any one of the second to sixth aspect further includes a process of acquiring a pump efficiency after the number of operating pumps is increased, a pump efficiency after the number of operating pumps is decreased, and a current pump efficiency based on a predetermined correlation between the discharge flow rate and the pump efficiency at the predetermined frequency of the pump in operation, wherein, in the process of increasing or decreasing the number of operating pumps, the number of operating pumps is further increased only when the pump efficiency after the number of operating pumps is increased is equal to or larger than the current pump efficiency, and the number of operating pumps is decreased only when the pump efficiency after the number of operating pumps is decreased is equal to or larger than the current pump efficiency.
  • a device for controlling number of pumps includes a number-of-pumps control unit configured to increase or decrease the number of operating pumps that are connected in parallel to forcibly feed a heat medium to a load based on a flow rate of the heat medium forcibly fed to the load or a heat load required by the load and a frequency command value commanded to each pump in operation among the plurality of pumps.
  • a pump system includes a plurality of pumps connected in parallel and the device for controlling number of pumps according to the eighth aspect, wherein the number of operating pumps is changed so that the pump head per pump and the flow rate measurement value are not changed.
  • a heat source system includes a load, a plurality of heat source machines configured to forcibly feed a heat medium and connected in parallel, a secondary pump configured to further forcibly feed the heat medium forcibly fed from the plurality of heat source machines connected in parallel to the load, and the device for controlling number of pumps according to the eighth aspect.
  • a program causes a computer of a device for controlling number of pumps to function as a unit configured to increase or decrease the number of operating pumps based on a flow rate of a heat medium that is forcibly fed to a load by a plurality of pumps connected in parallel or a heat load required by the load and a frequency command value commanded to each pump in operation among the plurality of pumps.
  • the device for controlling number of pumps the pump system, the heat source system, and the program described above, it is possible to appropriately control the number of operating pumps at an appropriate timing without knowing characteristics of facilities such as the pressure drop characteristics.
  • FIG. 1 is a schematic diagram showing a heat source system according to a first embodiment of the present invention.
  • FIG. 2 is a functional block diagram showing a device for controlling number of pumps according to the first embodiment of the present invention.
  • FIG. 3 is a diagram showing a process flow of the device for controlling number of pumps according to the first embodiment of the present invention.
  • FIG. 4 is a schematic diagram showing a heat source system according to a modified example of the first embodiment of the present invention.
  • FIG. 5 is a functional block diagram showing a device for controlling number of pumps according to the modified example of the first embodiment of the present invention.
  • FIG. 6 is a functional block diagram showing a device for controlling number of pumps according to a second embodiment of the present invention.
  • FIG. 7 is a diagram showing an example of Q-H characteristics indicating characteristics of a pump.
  • FIG. 8A is a diagram showing a change when the number of operating secondary pumps is increased from 1 to 2.
  • FIG. 8B is a diagram showing a change when the number of operating secondary pumps is increased from 1 to 2.
  • FIG. 9 is a diagram showing a process flow of the device for controlling number of pumps according to the second embodiment of the present invention.
  • FIG. 10 is a functional block diagram showing a device for controlling number of pumps according to a third embodiment of the present invention.
  • FIG. 11 is a diagram showing a process flow of the device for controlling number of pumps according to the third embodiment of the present invention.
  • FIG. 12 is a functional block diagram showing a device for controlling number of pumps according to the fourth embodiment of the present invention.
  • FIG. 13 is a diagram showing an example of a correlation between a pump discharge flow rate and pump efficiency.
  • FIG. 14 is a diagram showing a process flow of the device for controlling number of pumps according to the fourth embodiment of the present invention.
  • FIGS. 1 to 3 a heat source system according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3 .
  • FIG. 1 is a schematic diagram showing the heat source system according to the first embodiment of the present invention.
  • the heat source system of the present embodiment includes heat source machines 30 , primary pumps 10 , secondary pumps 20 , a load 40 , a flowmeter 21 , and a device for controlling number of pumps 50 .
  • the heat source machines 30 are devices that supply a heat medium for cooling or heating such as water to the load.
  • the primary pumps 10 forcibly feed the heat medium to the heat source machines 30 .
  • the heat source machines 30 are devices that supply a heat medium for cooling or heating such as water to a load.
  • a plurality of combinations of the heat source machines 30 and the primary pumps 10 may be installed in parallel.
  • FIG. 1 shows a state in which the plurality of primary pumps 10 are installed in parallel.
  • the secondary pumps 20 forcibly feed the heat medium fed from the heat source machines 30 to the load 40 .
  • the secondary pumps 20 are installed to be connected to each other in parallel, and control the flow rate of the heat medium to be supplied to the load 40 according to a request from the load 40 .
  • the flowmeter 21 is a flowmeter that measures a flow rate per unit time of the heat medium forcibly fed from the pumps.
  • the load 40 is, for example, an air conditioner.
  • the load 40 performs heat dissipation or heat absorption on the heat medium, and causes the resulting heat medium to flow back to the heat source machine 30 .
  • the device for controlling number of pumps 50 is a device having a function of increasing or decreasing the number of operating secondary pumps 20 according to a requested load required by the load 40 .
  • the two heat source machines 30 , the two primary pumps 10 , and the two secondary pumps 20 are installed, but the number of heat source machines 30 , the number of primary pumps 10 , and the number of secondary pumps 20 are not limited thereto.
  • the number of heat source machines 30 , the number of primary pumps 10 , and the number of secondary pumps 20 are not limited thereto.
  • six heat source machines 30 , six primary pumps 10 , and nine secondary pumps 20 may be installed.
  • a device that controls the number of operating heat source machines 30 such that a supply amount of the heat medium is adjusted according to the requested load of the load 40 may be installed.
  • FIG. 2 is a functional block diagram showing the device for controlling number of pumps according to the first embodiment of the present invention.
  • the device for controlling number of pumps 50 according to the present embodiment will be described with reference to FIG. 2 .
  • the device for controlling number of pumps 50 includes a number-of-pumps determination flow rate value acquiring unit 101 , a number-of-pumps determination frequency value acquiring unit 102 , a pump frequency setting unit 103 , a flow rate acquiring unit 104 , a number-of-pumps control unit 105 , and a storage unit 200 as shown in FIG. 2 .
  • the number-of-pumps determination flow rate value acquiring unit 101 reads and acquires a flow rate increase threshold value G ⁇ or a flow rate decrease threshold value G ⁇ serving as a threshold value used when increasing or decreasing the number of operating secondary pumps 20 according to the flow rate from the storage unit 200 .
  • the number-of-pumps determination flow rate value acquiring unit 101 calculates the number-of-pumps determination flow rate value, for example, according to the following Formula (1).
  • Gload is a measurement value of the flow rate of the heat medium such as water forcibly fed from all the secondary pumps 20 which are in operation.
  • G 0 i is a rated flow rate of the secondary pumps which are currently in operation.
  • the number-of-pumps determination flow rate value is a ratio of the measurement values of the discharge flow rates by all the pumps in operation with respect to a sum of the rated flow rates of the secondary pumps in operation.
  • the number-of-pumps determination frequency value acquiring unit 102 reads and acquires a frequency increase threshold value F ⁇ or a frequency decrease threshold value F ⁇ used when increasing or decreasing the number of operating secondary pumps 20 according to a frequency from the storage unit 200 .
  • the number-of-pumps determination frequency value acquiring unit 102 acquires a frequency command value that is output from the pump frequency setting unit 103 to the secondary pumps 20 from the pump frequency setting unit 103 , and uses the acquired frequency command value as a number-of-pumps determination frequency value.
  • the pump frequency setting unit 103 gives a command indicating the frequency for operating the pumps to the secondary pump 20 .
  • the frequency is a frequency of electric power for rotating a motor for driving the secondary pump 20
  • the pump frequency setting unit 103 controls an output of the pumps by designating the frequency and changing the number of revolutions of the pumps.
  • the pump frequency setting unit 103 is assumed to output the same frequency command value to the plurality of secondary pumps 20 in the operation state.
  • the flow rate acquiring unit 104 acquires the flow rate of the heat medium measured by the flowmeter 21 .
  • the number-of-pumps control unit 105 increases the number of operating pumps when the flow rate of the heat medium forcibly fed by the pump or the frequency of the pump satisfies a predetermined condition. In the present embodiment, the number of operating pumps is increased when the following two conditions are satisfied.
  • the number-of-pumps determination frequency value is the same value as a frequency command value Fset that is output from the pump frequency setting unit 103 to the secondary pump 20 .
  • F ⁇ is a threshold value acquired by the number-of-pumps determination frequency value acquiring unit 102 .
  • the number-of-pumps control unit 105 increases the number of operating secondary pumps 20 .
  • the number-of-pumps control unit 105 decreases the number of operating pumps when the flow rate of the heat medium forcibly fed by the pump or the frequency of the pump satisfies a predetermined condition. In the present embodiment, when the following two conditions are satisfied, the number of operating pumps is decreased.
  • G ⁇ is a threshold value acquired by the number-of-pumps determination flow rate value acquiring unit 101 .
  • FP is a threshold value acquired by the number-of-pumps determination frequency value acquiring unit 102 .
  • the number-of-pumps determination frequency value is, for example, a frequency command value which is designated to the secondary pumps 20 by the pump frequency setting unit 103 .
  • G ⁇ the threshold value
  • F ⁇ the threshold value
  • the storage unit 200 holds the threshold values G ⁇ and F ⁇ used for determining whether or not the number of pumps is increased or decreased, information indicating characteristics of the secondary pumps 20 , or the like.
  • the characteristic information is, for example, Q-H characteristics, a graph indicating a correlation between the discharge flow rate of the pumps and the pump efficiency, or the like.
  • FIG. 3 is a diagram showing a process flow of the device for controlling number of pumps according to the present embodiment.
  • a process of increasing or decreasing the number of operating secondary pumps 20 through the device for controlling number of pumps 50 will be described with reference to the process flow of FIG. 3 .
  • the heat source system shown in FIG. 1 is operating, for example, the load 40 is the air conditioner, and when the user increases or decreases a temperature setting, the requested load is increased or decreased, and the device for controlling number of pumps 50 controls the number of operating secondary pumps 20 accordingly. Further, it is assumed that the sum of the flow rates of the secondary pumps 20 directly after the number of pumps is increased or decreased does not change from that before the number of pumps is increased or decreased, and the pump head (head of the pumps) per secondary pump 20 does not change.
  • the flow rate acquiring unit 104 acquires a flow rate per unit time measured by the flowmeter 21 (step S 1 ).
  • the flow rate measured by the flowmeter 21 is a total flow rate of the heat medium forcibly fed by the one or more secondary pumps 20 .
  • the measurement value is a value obtained by actually measuring the flow rate flowing through the pipe and thus can be considered to be a value in which the pressure drop characteristics of the pipe are reflected.
  • the number-of-pumps determination flow rate value acquiring unit 101 reads and acquires the threshold values G ⁇ and G ⁇ stored in the storage unit 200 .
  • the number-of-pumps determination flow rate value acquiring unit 101 calculates the number-of-pumps determination flow rate value using Formula (1) (step S 2 ).
  • the number-of-pumps determination flow rate value acquiring unit 101 outputs the values to the number-of-pumps control unit 105 .
  • the number-of-pumps determination frequency value acquiring unit 102 reads and acquires the threshold values F ⁇ and F ⁇ stored in the storage unit 200 .
  • the number-of-pumps determination frequency value acquiring unit 102 acquires the pump frequency command value that is commanded from the pump frequency setting unit 103 to the secondary pump 20 as the number-of-pumps determination frequency value (step S 3 ).
  • the number-of-pumps determination frequency value acquiring unit 102 outputs the values to the number-of-pumps control unit 105 .
  • the number-of-pumps control unit 105 evaluates Formula (2) and Formula (3), and performs determination of the “increase condition 1” and the “increase condition 2” (step S 4 ). Then, when both of the conditions are satisfied (Yes in step S 4 ), the number-of-pumps control unit 105 increases the number of secondary pumps 20 by starting up one of the secondary pumps 20 that are currently in the stop state (step S 5 ).
  • step S 4 When it is determined through comparison that none of the “increase condition 1” and the “increase condition 2” is satisfied (No in step S 4 ), the process proceeds to step S 6 .
  • the number-of-pumps control unit 105 evaluates Formula (4) and Formula (5), and performs determination of the “decrease condition 1” and the “decrease condition 2” (step S 6 ). Then, when both of the conditions are satisfied (Yes in step S 6 ), the number-of-pumps control unit 105 decreases the number of secondary pumps 20 by stopping one of the secondary pumps 20 which are currently in operation (step S 7 ).
  • step S 6 When it is determined through comparison that none of the “decrease condition 1” and the “decrease condition 2” is satisfied (No in step S 6 ), the process proceeds to step S 8 .
  • the device for controlling number of pumps 50 determines whether or not the heat source system has been stopped, for example, by an operation of the user according to a predetermined method.
  • the present process flow ends.
  • the process starting from step S 1 is repeated.
  • the pressure drop is large, and thus if the measurement value of the discharge flow rate is 100 m 3 /h although the secondary pump 20 is operating at a frequency of a value close to a maximum, control of increasing the number of operating secondary pumps 20 to 2 according to the threshold value that is set in advance is considered to be appropriate.
  • the pressure drop is small, and thus, for example, the secondary pump 20 is operated at a frequency that is about half a maximum frequency, and the flow rate of 100 m 3 /h is obtained.
  • the number of operating secondary pumps 20 it is not necessarily appropriate to increase the number of operating secondary pumps 20 , and there is also a possibility that the flow rate required by the load device can be supplied by increasing the frequency of the secondary pump 20 that is currently in operation.
  • the number of secondary pumps is increased. The increase in the number of pumps significantly changes the pressure and the flow rate of the heat medium flowing in the system.
  • the determination is performed based on the frequency command value in addition to the actual measurement value of the flow rate including the pressure drop information of the system, and thus it is possible to increase or decrease the number of secondary pumps 20 without knowing the details of facilities such as the pressure drop. Further, it is determined whether or not the number of pumps is increased or decreased using the pump frequency command value, and thus it is possible to increase or decrease the number of secondary pumps 20 in view of an available capacity of the pump, and, for example, control of increasing the number of pumps although there is a room in capability of the pump can be prevented. Thus, an increase or decrease in the number of pumps does not occur often, and the heat source system can be operated more stably than in the technique of the related art. Similarly, even when the number of pumps is decreased, the number of pumps can be prevented from being decreased although the capability of the pump can be decreased by decreasing the frequency.
  • a heat load required by the load 40 can be used instead of the flow rate of the heat medium.
  • the modified example will be described below with reference to FIGS. 4 and 5 .
  • FIG. 4 is a schematic diagram showing a heat source system according to the modified example of the present embodiment.
  • the heat source system of the modified example includes a thermometer 22 and a thermometer 23 .
  • the remaining configuration is the same as in the first embodiment.
  • the thermometer 22 is installed nearby an inlet of the load 40 .
  • the thermometer 22 measures the temperature of the heat medium to be supplied to the load 40 .
  • the thermometer 23 is installed nearby an outlet of the load 40 .
  • the thermometer 23 measures the temperature of the heat medium to flow from the load 40 back to the heat source machine 30 .
  • FIG. 5 is a functional block diagram showing the device for controlling number of pumps according to the modified example of the present embodiment.
  • the device for controlling number of pumps 50 of the modified example differs from that of the first embodiment in that the device for controlling number of pumps includes a temperature acquiring unit 110 , and includes a number-of-pumps determination heat load acquiring unit 111 instead of the number-of-pumps determination flow rate value acquiring unit 101 .
  • the remaining configuration of the present embodiment is the same as in the first embodiment.
  • the temperature acquiring unit 110 acquires the temperatures of the heat medium measured by the thermometer 22 and the thermometer 23 .
  • the number-of-pumps determination heat load acquiring unit 111 reads a heat load increase threshold value La and a heat load decrease threshold value L ⁇ serving as a predetermined threshold value from the storage unit 200 .
  • the number-of-pumps determination heat load acquiring unit 111 acquires the flow rate of the heat medium from the flow rate acquiring unit 104 , acquires the temperatures of the heat medium measured by the thermometer 22 and the thermometer 23 from the temperature acquiring unit 110 , and calculates a load (a heat load) required by the load 40 .
  • the heat load may be calculated using, for example, the following formula:
  • heat load flow rate of heat medium ⁇ (
  • the “flow rate of the heat medium” is a value that is measured by the flowmeter 21 and acquired from the flow rate acquiring unit 104 by the number-of-pumps determination heat load acquiring unit 111 .
  • the “temperature of the heat medium to flow back” is a temperature measured by the thermometer 23 and a value acquired from the temperature acquiring unit 110 by the number-of-pumps determination heat load acquiring unit 111 .
  • the “temperature of the heat medium to be supplied” is a temperature measured by the thermometer 22 and a value acquired from the temperature acquiring unit 110 by the number-of-pumps determination heat load acquiring unit 111 .
  • the specific heat of the heat medium and the specific gravity of the heat medium are recorded in the storage unit 200 in advance, and the number-of-pumps determination heat load acquiring unit 111 reads the values from the storage unit 200 .
  • the number-of-pumps control unit 105 increases the number of operating pumps when the heat load calculated by the number-of-pumps determination heat load acquiring unit 111 or the frequency of the pump acquired by the number-of-pumps determination frequency value acquiring unit 102 satisfies a predetermined condition. Specifically, the number of operating pumps is increased when the following two conditions are satisfied.
  • the number-of-pumps control unit 105 decreases the number of operating pumps when the heat load or the frequency of the pump satisfies a predetermined condition. Specifically, the number of operating pumps is decreased when the following two conditions are satisfied.
  • the increase condition 1-1 and the decrease condition 1-1 differ from those in the first embodiment.
  • the increase condition 2 and the decrease condition 2 are the same as those in the first embodiment.
  • step S 1 of FIG. 3 the flow rate acquiring unit 104 acquires the flow rate measured by the flowmeter 21 , and the temperature acquiring unit 110 further acquires the temperatures of the heat medium measured by the thermometer 22 and the thermometer 23 .
  • step S 2 the number-of-pumps determination heat load acquiring unit 111 reads the threshold values
  • the number-of-pumps determination heat load acquiring unit 111 acquires the flow rate of the heat medium from the flow rate acquiring unit 104 , and acquires the temperature of the heat medium to be supplied from the temperature acquiring unit 110 to the load 40 and the temperature of the heat medium to flow from the load 40 back to the heat source machine 30 . Then, the number-of-pumps determination heat load acquiring unit 111 calculates the heat load using Formula (6).
  • step S 4 the number-of-pumps control unit 105 performs determination of the “increase condition 1-1” and the “increase condition 2.”
  • step S 6 the number-of-pumps control unit 105 performs determination of the “decrease condition 1-1” and the “decrease condition 2.”
  • the threshold values G ⁇ , G ⁇ , F ⁇ , F ⁇ , L ⁇ , and L ⁇ used in the present embodiment and the modified example are values that are decided in advance through experimentation, simulation, or the like.
  • a heat source system according to a second embodiment of the present invention will be described below with reference to FIGS. 6 to 9 .
  • the second embodiment relates to an example in which repetition of an increase or a decrease in the number of pumps is prevented so that the operation of the pumps is more stably performed in addition to the first embodiment.
  • FIG. 6 is a functional block diagram showing the device for controlling number of pumps according to the present embodiment.
  • the device for controlling number of pumps 50 of the present embodiment differs from that of the first embodiment in that the device for controlling number of pumps includes a pump head acquiring unit 107 .
  • the remaining configuration of the present embodiment is the same as in the first embodiment.
  • the pump head acquiring unit 107 acquires the pump head of the secondary pumps 20 that are currently in operation among the secondary pumps 20 or the pump head after the number of secondary pumps is increased or decreased based on the Q-H characteristics stored in the storage unit 200 .
  • the pump head refers to a head of the pumps.
  • the Q-H characteristics refer to a performance curve of the pumps indicating a relation between the discharge flow rate and the pump head when the pumps are operated at a maximum frequency.
  • FIG. 7 shows an example of the Q-H characteristics.
  • the discharge flow rate (Q) and the pump head (H) of the pumps have a relation in which the pump head decreases as the discharge flow rate increases, and the Q-H characteristics draw a different trajectory according to a type of pump.
  • the Q-H characteristics indicating the Q-H correlation of the secondary pumps 20 used in the heat source system are stored in the storage unit 200 , and the pump head acquiring unit 107 acquires the pump head corresponding to the discharge flow rate of secondary pumps per secondary pump 20 before and after the number of pumps is increased or decreased using the Q-H characteristics.
  • FIGS. 8A and 8B are diagrams showing a change when the number of operating secondary pumps 20 is increased from 1 to 2.
  • a secondary pump 20 in the operation state from the beginning is referred to as a “pump 20 - 1 ,” and a second secondary pump 20 to be added is referred to as a “pump 20 - 2 .”
  • FIG. 8A is a diagram showing that one pump is in the operation state.
  • the flow rate per unit time which is forcibly fed by one pump 20 - 1 is indicated by GA, and the total flow rate per unit time which is forcibly fed by all pumps 20 - 1 is indicated by GinA.
  • GA The flow rate per unit time which is forcibly fed by one pump 20 - 1
  • GinA the total flow rate per unit time which is forcibly fed by all pumps 20 - 1
  • the frequency of the pump 20 - 1 is indicated by fA
  • a head of the pump 20 - 1 is indicated by HA.
  • FIG. 8B is a diagram showing that two pumps are in the operation state.
  • a flow rate per unit time which is forcibly fed by each of the pump 20 - 1 and the pump 20 - 2 is indicated by GB
  • a total flow rate per unit time which is forcibly fed by the two pumps, that is, the pump 20 - 1 and the pump 20 - 2 is indicated by GinB.
  • a frequency of the pump 20 - 1 and the pump 20 - 2 is indicated by fB
  • a head of the pump 20 - 1 and the pump 20 - 2 is indicated by HB.
  • the device for controlling number of pumps 50 performs control such that each of the secondary pumps 20 in the operation state has the same frequency regardless of the number of operating pumps. Further, the device for controlling number of pumps 50 performs control such that the total flow rate (GinA) and the pump head (HA) do not change before and after the number of secondary pumps 20 is increased or decreased when the number of secondary pumps 20 is increased or decreased. These conditions are prerequisites common to the first to fourth embodiments.
  • the secondary pumps 20 are assumed to operate at a frequency 1, and a discharge flow rate 1 is assumed to be obtained.
  • the discharge flow rate when the pumps operate at the maximum frequency can be obtained by multiplying the discharge flow rate 1 by a value obtained by dividing the maximum frequency by the frequency 1.
  • the Q-H characteristics are read using the obtained discharge flow rate of the maximum frequency, and the pump head corresponding to the discharge flow rate when the pumps operate at the maximum frequency is obtained.
  • the obtained pump head is multiplied by the square of the ratio of the current frequency 1 to the pump maximum frequency. A value obtained as a result is the pump head.
  • an increase permission pump head (HB′) is obtained using the following Formula (11).
  • the first term F(x) on the right side indicates a function for obtaining the pump head based on the discharge flow rate indicated by the Q-H characteristics.
  • F ⁇ is the frequency decrease threshold value described in the first embodiment.
  • fmax is the maximum frequency (the pump maximum frequency) of each secondary pump 20 .
  • the pump head obtained using the frequency decrease threshold value F ⁇ indicates the pump head (the increase permission pump head) when the number of secondary pumps 20 is decreased by 1 from a state in which the number of secondary pumps 20 is increased by 1.
  • the pump head acquiring unit 107 similarly obtains the pump head (HB) in the state after the number of pumps is increased using the following Formula (12).
  • the frequency or the flow rate before the increase is used because the number of secondary pumps 20 is increased so that the pump head does not change, and thus the pump head after the increase is equal to the current pump head (before the increase).
  • H B F ( G A ⁇ f max f A ) ⁇ ( f A f max ) 2 ( 12 )
  • the number-of-pumps control unit 105 performs determination of the following condition using the values in addition to the two increase conditions in the first embodiment.
  • the number-of-pumps control unit 105 increases the number of operating secondary pumps 20 when it is equal to or larger than the increase permission pump head in addition to the “increase condition 1” and the “increase condition 2.”
  • the increase permission pump head is a value that is obtained using the frequency decrease threshold value and used as a reference for decreasing the number of operating pumps after the number of operating pumps is increased. Since there is a possibility that the number of pumps will be decreased again if the pump head after the increase falls below the value even after the number of operating pumps is increased, the above condition is added in the present embodiment to eliminate such waste.
  • the decrease permission pump head is a value used as a reference for increasing the pump after the number of operating pumps is decreased.
  • the decrease permission pump head may be obtained using the following Formula (14).
  • the pump head acquiring unit 107 obtains the pump head (HB) in the state after the number of pumps is decreased using the following Formula (12).
  • the pump head after the decrease does not differ from the pump head before the number of pumps is decreased and thus can be obtained using Formula (12).
  • the number-of-pumps control unit 105 performs determination of the following condition using the values in addition to the two decrease conditions in the first embodiment.
  • the number-of-pumps control unit 105 decreases the number of operating secondary pumps 20 when it is equal to or less than the decrease permission pump head in addition to the “decrease condition 1” and the “decrease condition 2.”
  • This condition is a condition in consideration of the fact that there is a possibility that the number of pumps will be increased again after the number of operating pumps is decreased, similarly to the case of the increase.
  • FIG. 9 is a diagram showing a process flow of the device for controlling number of pumps according to the present embodiment.
  • a process of increasing or decreasing the number of operating secondary pumps 20 through the device for controlling number of pumps 50 will be described with reference to a process flow of FIG. 9 .
  • the same processes as those in FIG. 3 are denoted by the same reference numerals.
  • steps S 1 to S 3 are the same as those in the first embodiment.
  • the flow rate acquiring unit 104 acquires the flow rate measured by the flowmeter 21
  • the number-of-pumps determination flow rate value acquiring unit 101 acquires the threshold values G ⁇ and G ⁇ and the number-of-pumps determination flow rate value
  • the number-of-pumps determination frequency value acquiring unit 102 acquires the threshold values F ⁇ and F ⁇ and the number-of-pumps determination frequency value.
  • the pump head acquiring unit 107 obtains the pump head after the number of pumps is increased or decreased using Formula (12), obtains the increase permission pump head using Formula (11), and obtains the decrease permission pump head using Formula (14) (step S 10 ).
  • the number-of-pumps control unit 105 performs determination of the “increase condition 1,” the “increase condition 2,” and the “increase condition 3” (step S 11 ). Then, when all the three conditions are satisfied (Yes in step S 11 ), the number-of-pumps control unit 105 increases the number of operating secondary pumps 20 by 1 (step S 5 ).
  • step S 11 When it is determined through comparison that any of the “increase condition 1,” the “increase condition 2,” and the “increase condition 3” is not satisfied (No in step S 11 ), the process proceeds to step S 12 .
  • the number-of-pumps control unit 105 performs determination of the “decrease condition 1,” the “decrease condition 2,” and the “decrease condition 3” (step S 12 ). Then, when all the three conditions are satisfied (Yes in step S 12 ), the number-of-pumps control unit 105 decreases the number of operating secondary pumps 20 by 1 (step S 7 ).
  • step S 8 When it is determined through comparison that any of the “decrease condition 1,” the “decrease condition 2,” and the “decrease condition 3” is not satisfied (No in step S 12 ), the process proceeds to step S 8 .
  • the process of step S 8 is the same as that in FIG. 3 . In other words, the process starting from step S 1 is repeated until the heat source system is stopped.
  • the determination criterion as to whether or not the number of secondary pumps 20 is increased or decreased using the measured flow rate and the pump frequency has been described.
  • the determination as to whether or not the number of pumps is increased or decreased is performed again, and there is a possibility that the increase and the decrease will be repeated.
  • the number of pumps when the determination as to whether or not the number of pumps is increased or decreased is performed, the number of pumps is increased or decreased by performing a comparison of the pump operation state after the increase (decrease) with the pump head of the decrease (increase) threshold value estimated from the Q-H characteristics in addition to the flow rate measurement value and the pump frequency after the increase or the decrease, and thus the repetition of the increase and the decrease can be prevented.
  • the present embodiment may be combined with the modified example of the first embodiment.
  • the third embodiment relates to an example in which repetition of an increase or a decrease in the number of pumps is prevented so that the operation of the pump is more stably performed in addition to the first embodiment, similarly to the second embodiment.
  • FIG. 10 is a functional block diagram showing a device for controlling number of pumps 50 according to the present embodiment.
  • the device for controlling number of pumps 50 of the present embodiment differs from that of the first embodiment in that the device for controlling number of pumps 50 includes a pump frequency estimation value acquiring unit 108 .
  • the remaining configuration of the present embodiment is the same as in the first embodiment.
  • the pump frequency estimation value acquiring unit 108 acquires a pump frequency estimation value after the increase and a pump frequency estimation value after the decrease serving as an estimation value of a frequency after the number of secondary pumps 20 is increased or decreased.
  • the pump head after the increase may be obtained using Formula (16).
  • H B F ( n n + m ⁇ G A ⁇ f max f B ) ⁇ ( f B f max ) 2 ( 16 )
  • the necessary discharge flow rate ((n/n+m) ⁇ GA) per pump after the increase at the pump frequency (fB) after the increase is obtained, and the pump head (HB) after the increase is obtained by multiplying the pump head acquired from the Q-H characteristics by the square of the ratio of the pump frequency (fB) after the increase to the pump maximum frequency (fmax) based on the discharge flow rate at the pump maximum frequency in this case.
  • the pump frequency estimation value acquiring unit 108 derives the frequency fB at which HB is HA using this relation from a map or an inverse function indicating a correlation between a frequency and a pump head which is prepared in advance, and uses fB as the pump frequency estimation value after the increase.
  • the number-of-pumps control unit 105 performs increase permission determination (an “increase condition 4”) based on the frequency that prevents the decrease condition from being triggered again after the increase in addition to the “increase condition 1” and the “increase condition 2.”
  • fB is the pump frequency estimation value after the increase acquired by the pump frequency estimation value acquiring unit 108
  • F ⁇ is the frequency decrease threshold value described in the first embodiment.
  • the determination after the decrease is similarly performed.
  • the pump frequency estimation value acquiring unit 108 substitutes the flow rate or the pump maximum frequency per pump after the decrease into Formula (18), and acquires the pump frequency estimation value fB after the decrease from a map or an inverse function using the fact that the value of Formula (18) is equal to HA.
  • H B F ( n n - m ⁇ G A ⁇ f max f B ) ⁇ ( f B f max ) 2 ( 18 )
  • the number-of-pumps control unit 105 performs decrease permission determination (the “decrease condition 4”) based on the frequency that prevents the increase condition from being triggered again after the decrease in addition to the “decrease condition 1” and the “decrease condition 2.”
  • fB is the pump frequency estimation value after the decrease acquired by the pump frequency estimation value acquiring unit 108
  • F ⁇ is the frequency increase threshold value described in the first embodiment.
  • FIG. 11 is a diagram showing a process flow of the device for controlling number of pumps according to the present embodiment.
  • a process of increasing or decreasing the number of operating secondary pumps 20 through the device for controlling number of pumps 50 will be described with reference to a process flow of FIG. 11 .
  • the same processes as those in FIG. 3 are denoted by the same reference numerals.
  • steps S 1 to S 3 are the same as those in the first embodiment.
  • the pump frequency estimation value acquiring unit 108 acquires an estimation value fB of the pump frequency after the number of pumps is increased or decreased according to the map or the inverse function (step S 13 ).
  • the number-of-pumps control unit 105 performs determination of the “increase condition 1,” the “increase condition 2,” and the “increase condition 4” (step S 14 ). Then, when all the three conditions are satisfied (Yes in step S 14 ), the number-of-pumps control unit 105 increases the number of operating secondary pumps 20 by 1 (step S 5 ).
  • step S 14 When it is determined through comparison that any of the “increase condition 1,” the “increase condition 2,” and the “increase condition 4” is not satisfied (No in step S 14 ), the process proceeds to step S 15 .
  • the number-of-pumps control unit 105 performs determination of the “decrease condition 1,” the “decrease condition 2,” and the “decrease condition 4” (step S 15 ). Then, when all the three conditions are satisfied (Yes in step S 15 ), the number-of-pumps control unit 105 decreases the number of operating secondary pumps 20 by 1 (step S 7 ).
  • step S 8 When it is determined through comparison that any of the “decrease condition 1,” the “decrease condition 2,” and the “decrease condition 3” is not satisfied (No in step S 12 ), the process proceeds to step S 8 .
  • the process of step S 8 is the same as that in FIG. 3 . In other words, the process starting from step S 1 is repeated until the heat source system is stopped.
  • the pump frequency after the increase (decrease) is estimated, and the value is compared with the frequency decrease (increase) threshold value. Then, in addition to the two conditions described in the first embodiment, when the pump frequency estimation value after the increase exceeds the frequency decrease threshold value, the number of secondary pumps 20 is increased. Similarly, in addition to the two conditions described in the first embodiment, when the pump frequency estimation value after the decrease falls below the frequency increase threshold value, the number of secondary pumps 20 is decreased. Since the frequency after the number of secondary pumps 20 is increased or decreased is considered, the repetition of the increase and the decrease can be prevented.
  • the present embodiment may be combined with the modified example of the first embodiment.
  • a heat source system according to a fourth embodiment of the present invention will be described below with reference to FIGS. 12 to 14 .
  • the fourth embodiment relates to an example in which the number of operating pumps is changed in view of the pump efficiency in addition to the first to third embodiments.
  • FIG. 12 is a functional block diagram showing a device for controlling number of pumps according to the present embodiment.
  • the device for controlling number of pumps 50 of the present embodiment differs from that of the first embodiment in that the device for controlling number of pumps 50 includes a pump frequency estimation value acquiring unit 108 and a pump efficiency acquiring unit 109 .
  • the remaining configuration of the present embodiment is the same as in the first embodiment.
  • the pump frequency estimation value acquiring unit 108 acquires the pump frequency estimation value after the increase and the pump frequency estimation value after the decrease using the map or the inverse function as described above in the third embodiment.
  • the pump efficiency acquiring unit 109 acquires the estimation value of the pump efficiency after the number of secondary pumps 20 is increased or decreased, for example, using a graph indicating a correlation between the discharge flow rate and the pump efficiency of the pump stored in the storage unit 200 .
  • FIG. 13 shows an example of the correlation between the discharge flow rate and the pump efficiency when the pump is operated at the maximum frequency.
  • FIG. 13 shows that the pump efficiency changes according to the discharge flow rate of the pump.
  • a current pump efficiency ⁇ A per pump in the state before the increase is obtained using the following Formula (20).
  • ⁇ (x) is a function indicating a relation between the discharge flow rate and the pump efficiency of the pump.
  • f B is the pump frequency estimation value after the increase calculated by the pump frequency estimation value acquiring unit 108 .
  • the number-of-pumps control unit 105 performs increase permission determination (the “increase condition 5”) based on the pump efficiency in addition to the “increase condition 1” and the “increase condition 2.”
  • the number-of-pumps control unit 105 does not increase the number of pumps unless the pump efficiency after the increase is equal to or larger than the pump efficiency before the increase in addition to the “increase condition 1” and the “increase condition 2.”
  • the pump efficiency acquiring unit 109 obtains the pump efficiency per pump after the decrease using the following Formula (23).
  • the number-of-pumps control unit 105 performs decrease permission determination (the “decrease condition 5”) based on the pump efficiency in addition to the “decrease condition 1” and the “decrease condition 2.”
  • the number-of-pumps control unit 105 does not decrease the number of pumps unless the pump efficiency after the decrease is equal to or larger than the pump efficiency before the decrease in addition to the “decrease condition 1” and the “decrease condition 2.”
  • the pump efficiency is considered, it is possible to increase or decrease the number of pumps while suppressing power consumption.
  • FIG. 14 is a diagram showing a process flow of the device for controlling number of pumps according to the present embodiment.
  • a process of increasing or decreasing the number of operating secondary pumps 20 through the device for controlling number of pumps 50 will be described with reference to a process flow of FIG. 14 .
  • the same processes as those in FIG. 11 are denoted by the same reference numerals.
  • Steps S 1 to S 3 are the same as those in the first to third embodiments.
  • Step S 13 is the same as in the third embodiment ( FIG. 11 ).
  • the pump efficiency acquiring unit 109 acquires the pump efficiencies before and after the number of pumps is increased or decreased (step S 17 ).
  • the number-of-pumps control unit 105 performs determination of the “increase condition 1,” the “increase condition 2,” and the “increase condition 5” (step S 18 ). Then, when all the three conditions are satisfied (Yes in step S 18 ), the number-of-pumps control unit 105 increases the number of operating secondary pumps 20 by 1 (step S 5 ).
  • step S 18 When it is determined through comparison that any of the “increase condition 1,” the “increase condition 2,” and the “increase condition 5” is not satisfied (No in step S 18 ), the process proceeds to step S 18 .
  • the number-of-pumps control unit 105 performs determination of the “decrease condition 1,” the “decrease condition 2,” and the “decrease condition 5” (step S 18 ). Then, when all the three conditions are satisfied (Yes in step S 18 ), the number-of-pumps control unit 105 decreases the number of operating secondary pumps 20 by 1 (step S 7 ).
  • step S 8 When it is determined through comparison that any of the “decrease condition 1,” the “decrease condition 2,” and the “decrease condition 5” is not satisfied (No in step S 18 ), the process proceeds to step S 8 .
  • the process of step S 8 is the same as in FIG. 3 . In other words, the process starting from step S 1 is repeated until the heat source system is stopped.
  • the present embodiment may be combined with the second or third embodiment as well as the first embodiment and the modified example of the first embodiment.
  • it is possible to prevent the repetition of the increase and the decrease in the number of secondary pumps 20 and decide the number of operating pumps so that the flow rate measurement value to the load is satisfied while searching for a good operation point at which the pump efficiency is good, and thus an energy saving effect can be expected.
  • the device for controlling number of pumps includes an internal computer.
  • the steps of each process of the device for controlling number of pumps is stored in a computer readable recording medium in the form of a program, and the above process is performed by reading the program through the computer.
  • the computer readable recording medium refers to a magnetic disk, a magneto-optical disc, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like.
  • the computer program may be delivered to the computer via a communication line, and the computer that has received the computer program may execute the program.
  • the program may be configured to implement some of the above-described functions.
  • the program may be configured to implement the above-described functions in combination with a program previously recorded in a computer system, that is, may be a differential file (a differential program).
  • the device for controlling number of pumps the device for controlling number of pumps, the pump system, the heat source system, and the program, it is possible to appropriately control the number of operating pumps at an appropriate timing without knowing characteristics of facilities such as the pressure drop characteristics.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Air Conditioning Control Device (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
US15/111,025 2014-01-31 2014-06-18 Method for controlling number of pumps, device for controlling number of pumps, pump system, heat source system, and program Abandoned US20160341440A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2014017187A JP6210219B2 (ja) 2014-01-31 2014-01-31 ポンプ台数制御方法、ポンプ台数制御装置、ポンプシステム、熱源システム及びプログラム
JP2014-017187 2014-01-31
PCT/JP2014/066141 WO2015114847A1 (ja) 2014-01-31 2014-06-18 ポンプ台数制御方法、ポンプ台数制御装置、ポンプシステム、熱源システム及びプログラム

Publications (1)

Publication Number Publication Date
US20160341440A1 true US20160341440A1 (en) 2016-11-24

Family

ID=53756451

Family Applications (1)

Application Number Title Priority Date Filing Date
US15/111,025 Abandoned US20160341440A1 (en) 2014-01-31 2014-06-18 Method for controlling number of pumps, device for controlling number of pumps, pump system, heat source system, and program

Country Status (5)

Country Link
US (1) US20160341440A1 (ja)
JP (1) JP6210219B2 (ja)
KR (1) KR101802105B1 (ja)
CN (1) CN105899886B (ja)
WO (1) WO2015114847A1 (ja)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2684152C1 (ru) * 2018-05-29 2019-04-04 Анатолий Александрович Рыбаков Способ подачи воздуха во внешнюю камеру сгорания двухтактного двигателя с внешней камерой сгорания из нескольких надпоршневых полостей компрессора
US10533781B2 (en) * 2015-05-13 2020-01-14 Mitsubishi Heavy Industries Thermal Systems, Ltd. Machine quantity controlling device, energy supplying system, machine quantity controlling method, and program
CN112432307A (zh) * 2020-11-17 2021-03-02 珠海格力电器股份有限公司 水泵评价方法、装置、空调系统、存储介质及电子设备

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7061923B2 (ja) * 2018-05-01 2022-05-02 東芝キヤリア株式会社 制御装置、熱源システム
JP7260770B2 (ja) * 2019-04-26 2023-04-19 ダイキン工業株式会社 ポンプ台数制御装置、ポンプ台数制御方法、ポンプ台数制御プログラム
KR102153313B1 (ko) * 2020-01-23 2020-09-08 (주)한국펌프앤시스템즈 부스터 펌프 시스템에서 펌프 운전 전환시 학습을 바탕으로 한 펌프 교대 방법
CN112780539B (zh) * 2020-12-31 2022-10-21 上海市政工程设计研究总院（集团）有限公司 一种同型号调速泵泵站节能运行的优化方法
CN113679988B (zh) * 2021-08-27 2023-02-28 广东瑞霖特种设备制造有限公司 压缩空气泡沫灭火系统的小流量分段控制机械传动泵组装置
CN114413360A (zh) * 2021-12-31 2022-04-29 威乐(中国)水泵系统有限公司 一种水力模块
WO2024100832A1 (ja) * 2022-11-10 2024-05-16 三菱電機株式会社 熱源システム

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5279581A (en) 1990-05-09 1994-01-18 Firth John R Disposable self-shielding hypodermic syringe
JPH0694946B2 (ja) * 1990-11-29 1994-11-24 東邦瓦斯株式会社 空調システム用流量検出装置
JP2006009805A (ja) 1996-01-31 2006-01-12 Hitachi Industrial Equipment Systems Co Ltd ターボ機械駆動装置及びその制御方法
JP3630283B2 (ja) 1999-02-08 2005-03-16 東光電気株式会社 冷温水ポンプの台数制御装置
JP3354891B2 (ja) 1999-03-09 2002-12-09 ダイダン株式会社 熱源台数制御装置
JP2004257707A (ja) 2003-02-27 2004-09-16 Hitachi Plant Eng & Constr Co Ltd 熱源機器の適正容量制御方法及び装置
JP2006153324A (ja) * 2004-11-26 2006-06-15 Yamatake Corp 運転台数制御方法および装置
JP5261153B2 (ja) * 2008-11-28 2013-08-14 株式会社大気社 熱源システム
US8939196B2 (en) * 2009-02-13 2015-01-27 Toshiba Carrier Corporation Secondary pump type heat source and secondary pump type heat source control method
JP5246118B2 (ja) * 2009-09-18 2013-07-24 日立電線株式会社 冷水循環システム
JP5399948B2 (ja) * 2010-03-01 2014-01-29 株式会社Ｎｔｔファシリティーズ 冷水循環システム
CN101832622B (zh) * 2010-05-25 2011-12-07 西安工程大学 用蒸发式冷水机组实现一次泵变流量系统连续调节的方法
CN102094801A (zh) * 2010-12-27 2011-06-15 贵州汇通华城楼宇科技有限公司 基于输送能耗最低的泵组优选方法
JP5558400B2 (ja) * 2011-03-30 2014-07-23 三菱重工業株式会社 熱源システム及び熱源システムの台数制御方法
JP6198398B2 (ja) * 2013-01-28 2017-09-20 新日本空調株式会社 ２ポンプ方式熱源設備におけるポンプ運転台数決定制御方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10533781B2 (en) * 2015-05-13 2020-01-14 Mitsubishi Heavy Industries Thermal Systems, Ltd. Machine quantity controlling device, energy supplying system, machine quantity controlling method, and program
RU2684152C1 (ru) * 2018-05-29 2019-04-04 Анатолий Александрович Рыбаков Способ подачи воздуха во внешнюю камеру сгорания двухтактного двигателя с внешней камерой сгорания из нескольких надпоршневых полостей компрессора
CN112432307A (zh) * 2020-11-17 2021-03-02 珠海格力电器股份有限公司 水泵评价方法、装置、空调系统、存储介质及电子设备

Also Published As

Publication number Publication date
KR101802105B1 (ko) 2017-11-27
JP2015143591A (ja) 2015-08-06
CN105899886A (zh) 2016-08-24
KR20160093722A (ko) 2016-08-08
WO2015114847A1 (ja) 2015-08-06
JP6210219B2 (ja) 2017-10-11
CN105899886B (zh) 2018-11-13

Similar Documents

Publication Publication Date Title
US20160341440A1 (en) Method for controlling number of pumps, device for controlling number of pumps, pump system, heat source system, and program
US9957970B2 (en) Device and method of controlling cooling towers, and heat source system
US11060741B2 (en) Heat source system and control method therefor
KR101618487B1 (ko) 열원 시스템의 대수 제어장치 및 그 방법 및 열원 시스템
US10197301B2 (en) Heat source system, and control device and control method therefor
US10352293B2 (en) Fluid system
KR101445992B1 (ko) 열매체 유량 추정 장치, 열원기 및 열매체 유량 추정 방법
US10655868B2 (en) Device for controlling number of operating heat source devices, heat source system, control method, and program
JP2007240131A (ja) 熱源機廻りの最適化制御
JP5201183B2 (ja) 空調装置および冷凍機の運転方法
JP4981530B2 (ja) 熱源システムの流量制御装置および熱源システムの流量制御方法
JP2016006355A (ja) 集中式熱源システムの制御方法及び制御装置
JP5492713B2 (ja) 送水温度制御装置および方法
JP6456261B2 (ja) 燃料電池スタック冷却装置
JP6029363B2 (ja) 熱源システム
JP4563891B2 (ja) 運転台数制御装置および方法
JP2020012564A (ja) 台数制御装置及びプログラム
US20230150352A1 (en) Oil Temperature Control Method, Controller, Powertrain, and Electric Vehicle
JP2010127564A (ja) 熱源システム
US10907542B2 (en) Compressed air energy storage power generation device
JP6301784B2 (ja) 熱源システムに使用される制御装置、および該制御装置を備えた熱源システム
JP6832732B2 (ja) 冷凍システム
JP2009243718A (ja) 熱媒体の搬送システム
CN109790990B (zh) 热源系统、控制装置及方法和计算机可读取的记录介质
KR101560511B1 (ko) 온수 가열 시스템 및 제어 장치 및 제어 방법

Legal Events

Date Code Title Description
AS Assignment

Owner name: MITSUBISHI HEAVY INDUSTRIES, LTD., JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OUCHI, TOSHIAKI;NIKAIDO, SATOSHI;MATSUO, MINORU;AND OTHERS;REEL/FRAME:039142/0133

Effective date: 20160701

AS Assignment

Owner name: MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD., JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MITSUBISHI HEAVY INDUSTRIES, LTD.;REEL/FRAME:043042/0757

Effective date: 20170629

Owner name: MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD.,

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MITSUBISHI HEAVY INDUSTRIES, LTD.;REEL/FRAME:043042/0757

Effective date: 20170629

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: NOTICE OF ALLOWANCE MAILED -- APPLICATION RECEIVED IN OFFICE OF PUBLICATIONS

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO PAY ISSUE FEE