JP2011242057A - Water supply control system and control method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water supply control system that transfers the heat by a necessary minimum pump discharge pressure, and to provide a control method of the system.SOLUTION: The water supply control system includes: a primary-side pump 7 that circulates primary-side cold/warm water between a heat source 1 and a plurality of heat exchangers 2A, 2B; an inverter 7a controlling the number of rotation of the pump; a plurality of primary-side flow regulating valves V1, V2 regulating flow rates of the primary-side cold/warm water; pressure sensors 10, 11 detecting input and output pressures; a control device 8 that controls opening degrees of the plurality of primary-side flow regulating valves; a plurality of secondary-side pumps 12, 13; a plurality of flow rate sensors F1, F2 for secondary-side cold/warm water; and a plurality of temperature sensors T1 to T4 for measuring temperature. The control device calculates an appropriate flow amount of the primary-side cold/warm water in each heat exchanger based on the heat exchange quantity, calculates an optimal pressure difference of each heat exchanger, identifies a heat exchanger that most requires circulation pumping based on a difference between the optimal pressure difference and an actual pressure difference, and controls the number of revolutions of the pump through the inverter.

Description

  The present invention relates to a water supply control system that controls the flow rate of a pump that supplies cold / hot water generated by a heat source device to a plurality of load devices, and a water supply control method, and in particular, can supply water to a plurality of load devices with minimum power. The present invention relates to a water supply control system and a control method thereof.

  In a water supply control system that transports cold / hot water using a conventional district heating / cooling system, etc., a method for reducing the transport power according to the heat load is to use multiple pumps so that the discharge pressure of the forward header is constant. A method of controlling the number of operating units and the number of pump revolutions with an inverter, a piping route that requires the most circulating head, and estimating the water supply pressure required by that route from the flow rate, adopting estimated terminal pressure control, etc. There is a way.

  In the method of controlling the number of pumps operated and the number of pump rotations so that the discharge pressure of the forward header becomes constant, it is difficult to grasp the maximum head required by the piping path as needed. Therefore, it is necessary to set the discharge pressure of the forward header so as to avoid a shortage of heat exchange due to a shortage of head and a decrease in flow rate. As a result, depending on the magnitude of the heat demand of the load equipment, water may be fed at a pressure higher than the head required by the piping path. In addition, since the estimated terminal pressure control depends on the reduction effect of the conveyance power on the estimation accuracy, complicated system tuning is required to increase the estimation accuracy in order to obtain a greater reduction effect. Become.

  Conventionally, as this type of water supply pressure control system, there are a pump for supplying water to which the pressure is added to the return water from the load device, a pump for supplying the return water, and a pump for outputting the water supply. A bypass valve provided in the bypass connecting to the output side of the power supply, a sensor for measuring the pressure of the water supplied to the load device at the end, and the water supplied from the pump based on the pressure measured by the sensor It is possible to reduce the energy required for the pump head, and as a result, further energy saving can be realized (see, for example, Patent Document 1).

  In addition, another water supply pressure control system includes a heat source device that generates cold / hot water, a plurality of load devices provided between the outlet and return water pipelines of the cold / hot water from the heat source device, and these load devices. A control device that controls the supply pressure of the cold / hot water from the heat source device to each of the load devices, and each load device has a flow rate measuring means for measuring the flow rate of the cold / warm water flowing to the load device as a load device flow rate, Differential pressure measuring means for measuring the differential pressure between the inlet side and outlet side of the valve for adjusting the flow rate of the cold / hot water flowing to the load equipment as the valve differential pressure, and the control device is provided with a flow rate measuring means for each load equipment. Load equipment differential pressure estimation that estimates the differential pressure applied between the input side and output side of the load equipment as the load equipment differential pressure from the load equipment flow rate measured by the valve and the valve differential pressure measured by the differential pressure measuring means Means and load device differential pressure estimating means Therefore, it is provided with a water supply pressure setting means for setting the water supply pressure of the cold / hot water from the heat source device to the load device based on the estimated minimum value in the load device differential pressure for each load device. There is no need to search, and the supply pressure of cold / hot water from the heat source unit to the load device can be adjusted according to the situation without installing a dedicated differential pressure sensor to measure the end differential pressure at the load device located at the end. Thus, energy saving can be achieved (for example, see Patent Document 2).

JP 2005-299980 A JP 2009-121722 A

  By the way, in a normal water supply control system, when transporting the heat produced in one place to a plurality of heat demand destinations, the pump and the water supply pressure are matched to the route leading to the load equipment with the largest required pressure. Is set. However, there are cases where it is difficult to identify the route with the highest required pressure at the design stage, and there are cases where the route with the highest required pressure changes due to repair work after completion.

  In the water supply control device and method described in Patent Document 1, the heat exchanger at the physical end is a heat exchanger that controls the pump head. However, if there is a heat exchanger with a large heat demand on the way, it is not considered that the heat exchanger can be a heat exchanger that dominates the pump head, so a heat exchanger that dominates the pump head Things that cannot be accurately identified can occur.

  In addition, the water pressure control system described in Patent Document 2 adds the differential pressure of the control valve attached to the load device and the assumed differential pressure of the load device, and according to the smallest differential pressure of the load device, Control the pumping water pressure. With this method, the load equipment that requires the most circulating head cannot be uniquely determined. That is, if the control valve is throttled even if the differential pressure of the control valve + the differential pressure of the load device is the same value, the differential pressure of the valve is “large”, the differential pressure of the load device is “small”, and the control valve is When open, the differential pressure of the valve can be “small” and the differential pressure of the load device can be “large”. Therefore, in this technique, although the control valve of the load device located at the end can be further opened and the discharge pressure of the pump can be reduced, there is a possibility that the valve remains in a steady state while being throttled.

  The present invention has been made in view of such problems, and the object of the present invention is to set a differential pressure that has been set in advance to the one that requires the most circulating head from among a plurality of heat exchangers. (Optimal differential pressure) and the measured differential pressure of the valve + heat exchanger are searched for and specified, and the number of revolutions of the pump is controlled by the inverter according to the heat exchanger. It is providing the water-feeding control system which can convey heat with the pump discharge pressure of.

  In order to achieve the above object, a water supply control system according to the present invention supplies primary side cold / warm water generated by a heat source device to a plurality of heat exchangers, and the primary side cold / warm water passes through the heat exchanger. A water supply control system for transferring thermal energy to secondary side cold / hot water and supplying it to a plurality of heat utilization devices, wherein the primary side cold / hot water is circulated between a heat source device and a plurality of heat exchangers. A pump, an inverter for controlling the rotational speed of the primary pump, and a plurality of primary flow rate adjusting valves for adjusting the flow rate of pipes for supplying the primary side cold / hot water to each of the plurality of heat exchangers; A pressure sensor for detecting the inlet / outlet pressure of the primary side cold / hot water in the inlet and outlet pipes of the plurality of heat exchangers, and the opening degree of the plurality of primary side flow control valves based on the pressure data of the pressure sensor And a control device for adjusting, between the plurality of heat exchangers and the plurality of heat utilization devices. A plurality of secondary pumps for feeding the side cold / hot water, a plurality of flow sensors for measuring the flow rate of the secondary cold / hot water, and the temperature of the secondary cold / warm water flowing into the plurality of heat exchangers 2 A plurality of temperature sensors for measuring the temperature of the secondary side cold / hot water, and the control device identifies a heat consumer most requiring a circulation head from the output of each flow sensor and the data of each temperature sensor; The rotation speed of the primary pump is controlled by an inverter based on the data of the specified heat consumer.

  The water supply control system of the present invention configured as described above specifies the heat consumer most requiring the circulation head from the output of each flow sensor and the data of each temperature sensor, and the data of the specified heat consumer Since the rotation speed of the primary side pump is controlled by the inverter based on the above, the primary side cold / hot water can be sent to a plurality of heat consumers with the minimum necessary power according to the heat demand.

  Moreover, as a preferable specific aspect of the water supply control system according to the present invention, the control device calculates a heat demand amount of each heat utilization device on the secondary side of each heat exchanger, and calculates the calculated heat demand. The flow rate of primary cold / hot water appropriate for each heat exchanger is calculated from the amount, and the appropriate differential pressure (hereinafter referred to as “optimal difference” for each heat exchanger when the valve opening is fully open based on the flow rate. And the heat consumer most requiring the circulation head is identified from the difference between the optimum differential pressure and the actual differential pressure.

  According to this configuration, the flow of secondary cold / hot water of each heat consumer, the temperature of cold / warm water flowing into each heat exchanger, and the temperature of cold / warm water flowing out of each heat exchanger, Calculate the required heat energy (heat demand), calculate the appropriate primary-side cold / hot water flow rate for each heat exchanger from this heat demand amount, and optimize the appropriate heat exchanger based on the flow rate Calculates the differential pressure, identifies the consumer who requires the most circulation head from the difference between the optimum differential pressure and the actual differential pressure, and controls the rotation speed of the primary pump with an inverter. The water can be sent with the minimum necessary power.

  Furthermore, as another preferable specific aspect of the water supply control system according to the present invention, the control device compares the difference between the optimum differential pressure and the actual differential pressure of the plurality of heat consumers, and When a heat consumer having a heat exchanger with the smallest difference between the differential pressure and the optimum differential pressure is identified as a heat consumer requiring the most circulation head, and the differential pressure in the heat exchanger is greater than or equal to the optimum differential pressure, the primary It is characterized in that the rotation speed of the side pump is reduced by an inverter. According to this configuration, the difference between the optimum differential pressure and the actual differential pressure of the heat consumer identified as requiring the most circulating head is compared, and when the actual differential pressure is greater than or equal to the optimum differential pressure, the primary side By reducing the number of rotations of the pump and increasing the number of rotations of the primary pump when the actual differential pressure is less than the optimum differential pressure, it is possible to perform pump control suitable for the circulation head required by the heat consumer. .

  Moreover, in the water supply control system of this invention, it is preferable that a control apparatus calculates optimal differential pressure | voltage from a map based on the flow volume of primary side cold / warm water appropriate for each calculated heat exchanger. With this configuration, the optimum differential pressure can be easily calculated, and control tuning can be easily performed by changing the map.

  The water supply control system of the present invention further includes a temperature sensor and a valve control device for measuring a return temperature of each primary side cold / warm water to the heat source unit, and the valve control device uses the return temperature of the temperature sensor and a set value. In comparison, when the return temperature is higher than a set value during cold water conveyance, the opening of the flow rate adjustment valve is increased, and when the return temperature is lower than the set value, the opening of the flow rate adjustment valve is decreased. The reverse control is performed at the time of conveyance. According to this configuration, while performing pump control according to the heat consumer identified as requiring the most circulating head, other customers can ensure the temperature difference between the inlet and outlet of the cold / hot water of the heat exchanger. And energy saving can be achieved.

  The water supply control system according to the present invention further includes a temperature sensor and a valve control device for measuring a forward temperature entering the heat exchanger of each primary side cold / hot water and a return temperature coming out of the heat exchanger, and the valve control device includes: It is preferable to compare the return temperature difference between the return temperature and the return temperature of the temperature sensor with the set value, and to control to increase the opening of the flow rate adjusting valve when the return temperature difference is equal to or greater than the set value. . According to this structure, it can develop into the control system which can respond even when the going temperature which enters into the heat exchanger of primary side cold / hot water deviates from assumption.

  The control method of the water supply control system according to the present invention is such that the primary side cold / warm water generated by the heat source unit is fed to a plurality of heat exchangers by a pump capable of controlling the number of revolutions, and the primary side cold / warm water is passed through the heat exchanger. A control method of a water supply control system that transmits thermal energy of water to secondary side cold / hot water and supplies it to a plurality of heat utilization devices, wherein the inflow temperature of secondary side cold / warm water on the secondary side of the heat exchanger, Calculate the heat demand (required heat energy) of each heat consumer from the outflow temperature and flow rate, and calculate the primary cold / hot water flow rate required for the primary heat exchanger from the calculated heat demand. The optimal primary side differential pressure for each heat exchanger is calculated from the calculated primary side cold / hot water flow, and the primary side differential pressure flowing into and out of the primary side of the plurality of heat exchangers is measured. Based on the measured primary side differential pressure and primary side optimum differential pressure of each heat exchanger, the most required circulating head Specify a large heat consumer, fully open the flow rate adjustment valve that adjusts the flow rate of the primary side cold / hot water of the identified heat consumer, or open the valve opening to a predetermined value and then change the pump speed to 1 It is characterized by changing the rotation speed of the secondary pump.

  The step of calculating the optimum primary side differential pressure optimum for each heat exchanger is preferably performed using a map, and when the primary side cold / hot water differential pressure of the heat exchanger is equal to or greater than the primary side optimum differential pressure. It is preferable to reduce the rotational speed of the pump. Furthermore, the control method of the water supply control system is a process for a heat consumer other than the heat consumer identified as having the greatest demand for the circulation head, when the return temperature of the primary side cold / hot water is equal to or higher than a set value. Control is performed such that the opening degree of the flow rate adjusting valve is increased and the opening degree of the flow rate adjusting valve is decreased when it is less than the set value. In addition, when the return temperature difference of the primary side cold / hot water of each heat exchanger is greater than or equal to the set value, the opening degree of the flow adjustment valve that adjusts the flow rate of the primary side cold / warm water is increased, and the return temperature difference becomes the set value. When it is less than the range, the flow rate adjustment valve may be controlled to decrease the opening.

  According to the control method configured as described above, the circulation head required by each heat consumer is grasped, and the pump discharge pressure of the primary side cold / hot water is adjusted in accordance with the heat consumer most requiring the circulation head from among them. In order to adjust, primary side cold / hot water can be sent with the minimum necessary power according to the circulation head which a consumer demands.

  The water supply control system and the control method thereof according to the present invention can efficiently deliver heat to a plurality of heat exchangers with the minimum necessary power when transporting the heat produced in one place (heat production plant). . Further, complicated tuning for increasing the accuracy of the terminal pressure control of the piping system becomes unnecessary, and energy saving can be easily achieved. Furthermore, it is possible to prevent the control system from becoming unstable even when the heat exchange amount changes suddenly between the primary side and the secondary side of the heat exchanger.

The block diagram which shows the principal part structure of one Embodiment of the water supply control system which concerns on this invention. The flowchart at the time of the cold water conveyance which shows the operation | movement which controls the flow rate adjustment valve which controls the pump which supplies the cold / hot water of the water supply control system of FIG. The flowchart at the time of the hot water conveyance which shows the operation | movement which controls the flow rate adjustment valve which controls the pump which supplies the cold / hot water of the water supply control system of FIG. The block diagram which shows the principal part structure of other embodiment of the water supply control system which concerns on this invention. The flowchart which shows the operation | movement which controls the flow rate adjustment valve which adjusts the flow volume of cold / hot water while controlling the pump which supplies cold / hot water of the water supply control system of FIG.

  Hereinafter, an embodiment of a water supply control system and a control method thereof according to the present invention will be described in detail with reference to the drawings. The block diagram of FIG. 1 shows a schematic configuration of a water supply control system according to the present embodiment, and the flowchart of FIG. 2 performs control to increase or decrease the rotation speed of a pump that supplies cold / hot water of the water supply control system of FIG. In addition, control for adjusting the flow rate of the primary side cold / hot water by opening and closing the flow rate adjustment valve is shown.

  In FIG. 1, the water supply control system of the present embodiment is a water supply control system that is optimal for water supply of cold / hot water that conveys heat by a district cooling / heating device or the like, and a plurality of primary-side cold / hot water generated by the heat source device 1 Are sent to the heat exchangers 2A, 2B, ..., which are the load devices of the heat consumers A, B ..., and the heat energy of the primary side cold / warm water is transmitted to the secondary side cold / hot water via the heat exchanger, and a plurality of heat It is a water supply control system supplied to utilization apparatus 3A, 3B .... The heat utilization device is, for example, an air conditioner. When heat energy is sent to a plurality of heat utilization devices, a forward header (not shown) is connected to the end of the forward conduit 5a, and the return conduit 5b is connected to the end of the return conduit 5b. It is preferable to connect the return path header (not shown) and distribute cold / hot water. The primary side cold / warm water is often set to about 7 ° C. for cooling and about 50 ° C. for heating.

  The primary-side cold / hot water is sent from the heat source unit 1 through the conduit 4 to the heat exchangers 2A, 2B... Of each heat consumer and returned to the heat source unit 1. Flow control valves V1, V2 are installed in the forward path 4a of the conduit 4 and the branched forward path 4c to adjust the flow rate of the primary side cold / hot water to the heat exchangers 2A, 2B. The heat exchangers 2A, 2B,... Transmit the heat energy of the primary side cold / warm water to the secondary side cold / warm water.

  The secondary cold / hot water circulates through a plurality of heat exchangers 2A, 2B... For each heat consumer and a plurality of heat utilization devices 3A, 3B. . The primary side conduit 4 includes an outward route 4a and a branched outward route 4c, and a return route 4b and a branched return route 4d. The secondary side conduit 5 of the heat exchanger 2A is also connected to the outward route 5a and the return route 5b. The secondary side conduit 6 of the heat exchanger 2B also includes an outward path 6a and a return path 6b.

  The water supply control system of the present embodiment includes a heat source unit 1, a pump 7 that conveys primary cold / hot water generated by the heat source unit, an inverter 7a that controls the rotational speed of the pump 7, and an inverter that controls the inverter. The control device 8 constitutes a common heat plant, and the plurality of heat consumers are defined as downstream of the flow rate adjusting valves V1, V2 of the conduit 4, and between the heat plant and the plurality of heat consumers A, B. It is configured by connecting with a conduit 4 comprising an outward path and a return path.

  Further, the control device 8 of this embodiment includes an inverter control device 8a and a valve control device 8b. The inverter control device 8a controls the rotation of the pump by changing the frequency to the inverter 7a of the pump 7 based on data input from various sensors, and the valve control device 8b is similarly based on the data from various sensors. Thus, the opening degree of the flow rate adjusting valves V1, V2 is adjusted.

  Since the conduit configuration for each heat consumer is basically the same, the first heat consumer A will be described in detail. A primary pump 7 is installed in the forward path 4 a of the primary side conduit 4. The pump 7 is provided with an inverter 7a, and has a configuration in which the rotation speed can be changed by changing the frequency by a signal from the inverter control device 8, and the water supply capacity of the pump can be changed. Between the pump 7 and the heat exchanger 2A, a flow rate adjustment valve V1 for adjusting the flow rate of the cold water on the primary side is installed. Then, the inverter control device 8a calculates the optimum differential pressure (differential pressure between the valve inlet and the heat exchanger outlet when the valve opening is fully opened) according to the heat exchange amount.

  A differential pressure sensor 10 is installed between the forward path 4a and the return path 4b of the primary side conduit 4. The differential pressure sensor 10 measures a differential pressure ΔP12 between the pressure P1 of the forward path 4a and the pressure P2 of the return path 4b, and data of the differential pressure sensor is input to the control device 8. By comparing the actual measurement value measured by the differential pressure sensor 10 with the optimum differential pressure calculated by the inverter control device 8a, the heat exchanger that most requires the circulation head is specified. That is, the optimum differential pressure and the measured differential pressure are compared for each of the heat exchangers 2A, 2B..., And the heat exchanger having the smallest difference between the optimum differential pressure and the measured differential pressure is the heat exchanger that requires the most circulating head. Judge that there is. In addition, a temperature sensor Ta is installed in the return path 4b, and this temperature sensor measures the temperature of the primary side cold / warm water flowing out of the heat exchanger 2A. The output of the temperature sensor Ta is input to the control device 8. The valve control device 8b is configured to adjust the opening degree of the flow rate adjusting valve V1 based on the output of the temperature sensor Ta.

  On the secondary side of the heat exchanger 2A, a conduit 5 having an outward path 5a and a return path 5b is connected, and a heat utilization device 3A is connected to the ends of the outward path 5a and the return path 5b. A secondary pump 12 is installed in the middle of the forward path 5a, and the secondary cold / hot water is circulated between the heat exchanger 2A and the heat utilization device 3A by this pump. A regulating valve V3 is installed between the forward conduit 5a and the return conduit 5b, and a regulating valve V4 is installed in the return channel between the regulating valve V3 and the heat exchanger 2A.

  Further, a flow rate sensor F1 is installed downstream of the secondary side pump 12 of the forward conduit, and the temperature sensors are respectively provided on the side flowing out from the heat exchanger 2A of the secondary side cold / hot water and the side flowing into the heat exchanger 2A. T1 and T2 are installed. The temperature sensor T1 measures the temperature of the secondary side cold / hot water exiting from the heat exchanger 2A, and the temperature sensor T2 measures the temperature of the secondary side cold / warm water entering the heat exchanger 2A. The outputs of the flow sensor F1 and the temperature sensors T1 and T2 are input to the control device 8. With this configuration, the control device 8 calculates the frequency to be supplied to the inverter 7a of the pump 7 based on the outputs of the differential pressure sensor 10, the temperature sensor Ta, the temperature sensors T1 and T2, and the flow rate sensor F1, and the inverter control device 8a is 1. Control is performed to increase / decrease the number of rotations of the pump 7 of the secondary side cold / hot water, and the capacity of the pump 7 of the primary side cold / hot water is controlled.

  The second heat consumer B has basically the same structure as the first heat consumer A, and the branched forward path 4 c and return path 4 d are connected to the heat exchanger 2 B, and the forward path of the conduit 4. A differential pressure sensor 11 is installed between 4c and the return path 4d. The differential pressure sensor 11 measures a differential pressure ΔP12 between the pressure P1 of the forward path 4c and the pressure P2 of the return path 4d, and the output of the differential pressure sensor is input to the inverter control device 8. Further, a temperature sensor Tb is installed in the return path 4d, and this temperature sensor measures the temperature of the primary side cold / hot water flowing out from the heat exchanger 2B. The output of the temperature sensor Tb is input to the control device 8. The valve control device 8b is configured to adjust the opening of the flow rate adjustment valve V2 based on the output of the temperature sensor Tb.

  On the secondary side of the heat exchanger 2B of the second heat consumer B, a conduit 6 having an outward path 6a and a return path 6b is connected, and heat terminals such as an air conditioner are used at the ends of the outward path 6a and the return path 6b. Device 3B is connected. A secondary pump 13 is installed in the middle of the forward path 6a, and the secondary cold / hot water is circulated between the heat exchanger 2B and the heat utilization device 3B by this pump. A regulating valve V5 is installed between the forward conduit 6a and the return conduit 6b, and a regulating valve V6 is installed in the return channel between the regulating valve V5 and the heat exchanger 2B.

  Further, a flow rate sensor F2 is installed downstream of the secondary side pump 13 of the forward conduit, and the temperature sensors are respectively provided on the side flowing out from the heat exchanger 2B of the secondary side cold / hot water and the side flowing into the heat exchanger 2B. T3 and T4 are installed. The temperature sensor T3 measures the temperature of the secondary side cold / hot water exiting from the heat exchanger 2B, and the temperature sensor T4 measures the temperature of the secondary side cold / warm water entering the heat exchanger 2B. Outputs from the flow sensor F2 and the temperature sensors T3 and T4 are input to the control device 8. With this configuration, the control device 8 calculates the frequency to be supplied to the inverter 7a of the pump 7 based on the outputs of the differential pressure sensor 11, the temperature sensor Tb, the temperature sensors T3 and T4, and the flow rate sensor F2, and the inverter control device 8a is 1. Control is performed to increase / decrease the rotation speed of the pump 7 of the secondary side cold / hot water, and the pressure of the pump 7 of the primary side cold / hot water is controlled.

  A control method of the water supply control system of the present embodiment configured as described above will be described with reference to the flowchart of FIG. The control device 8 calculates the amount of heat demand on the receiving secondary side of each thermal heat consumer in step S1. That is, the flow rate of the secondary side cold / hot water on the secondary side of the heat exchanger 2A is measured with a flow meter, the outlet temperature from the secondary side cold / warm water heat exchanger is measured with a temperature sensor, and the secondary side cold / hot water is measured. The temperature at the entrance to the heat exchanger is measured with a temperature sensor, and the heat demand of each heat consumer is calculated based on the temperature difference and flow rate of the two temperature sensors.

  Thereafter, based on the heat demand of each heat consumer calculated in step S1, an appropriate primary side cold / hot water flow rate (Fs) of each heat exchanger is calculated in step S2. In step S3, an appropriate primary differential pressure (optimal differential pressure ΔPs) of each heat exchanger is calculated from the flow rate of the primary cold / hot water calculated in step S2 using the map M. Calculation can be easily performed by using the map M, and control tuning can be easily performed by correcting the map. Moreover, by using the map, it is possible to prevent the control system from becoming unstable when a transient change in the heat exchange amount occurs.

  On the other hand, on the primary side of the heat exchanger, the actual primary side return pressure (ΔP12) of each heat exchanger is acquired. That is, in step S4, an actual differential pressure (ΔP12) is obtained from the inlet pressure P1 of the primary side cold / hot water flowing into the heat exchanger and the outlet pressure P2 of the primary side cold / warm water flowing out of the heat exchanger. In step S5, the heat consumer requiring the most circulation head is specified from the difference between the optimum differential pressure ΔPs calculated in step S3 and the primary-side return differential pressure ΔP12 acquired in step S4. That is, among the plurality of heat consumers, a consumer having a small difference between the optimum differential pressure ΔPs and the primary side return differential pressure ΔP12 is specified as the customer requiring the most circulation head.

  And with respect to the specified heat consumer, the opening degree of a flow regulating valve is opened to a predetermined value at Step S6, or the opening degree is fully opened. In this process, opening the flow rate adjustment valve to a predetermined value means opening only a preset step, and by fully opening it, the power consumption of the pump can be minimized, but a rapid change In order to prevent the instability of the control due to, it has been selected to open in stages. Thereafter, in step S7, it is determined whether each heat exchanger primary-side return differential pressure ΔP12 is equal to or higher than the optimum differential pressure ΔPs, which is a target value. If so, the frequency of the pump inverter is decreased in step S8 to start the operation. Return. On the other hand, when each heat exchanger primary-side return differential pressure ΔP12 is less than the target value optimum differential pressure ΔPs, the frequency of the pump inverter is increased in step S9, and the process returns to the start.

  In this way, among the plurality of heat consumers, the consumer that most requires the circulation head is identified from the difference between the optimum differential pressure ΔPs and the primary side return differential pressure ΔP12, and the primary side cold temperature is matched to this consumer. Since the head of the pump that transports the water is controlled by the inverter, the primary side cold / warm water can be transported efficiently with the minimum necessary power.

  Moreover, about the other heat consumers which are not the heat consumers specified by step S5, the return temperature of each heat exchanger primary side cold water is compared with a setting value by step S10. The set value of cold water is usually set to about 5 to 10 ° C. If the return temperature of the primary side chilled water is equal to or higher than the set value, in step S11, control is performed to increase the opening of the flow rate adjustment valve in a preset step, and the flow rate of the primary side chilled water is increased to start. Return. When the return temperature of the primary side chilled water is lower than the set value, control is performed to reduce the opening of the flow rate adjusting valve in a step set in advance in step S12, and the flow rate of the primary side chilled water is decreased. Return to start. The control of increasing or decreasing the opening degree of the flow rate adjusting valve in steps S11 and S12 is performed step by step, and the size of the step is adjusted by the length of the piping path and the amount of water held by the piping path.

  Next, a control method during hot water transfer of the water supply control system of the present embodiment will be described with reference to the flowchart of FIG. The description of the same steps S1 to S9 as the description of the flowchart of FIG. In the case of warm water, the flow rate adjustment valve is operated in reverse to the cold water in steps S15 to S17. That is, in step S5, the return temperature of each heat exchanger primary-side hot water is compared with the set value in step S15 for heat consumers other than those specified as heat consumers requiring the most circulating head. In general, the set value of hot water is often set to about 50 ° C.

  When the return temperature of the primary side hot water is equal to or higher than the set value, in step S16, control is performed to decrease the opening of the flow rate adjustment valve in a preset step, and the flow rate of the primary side hot water is reduced to start. Return. When the return temperature of the primary-side hot water is lower than the set value, control is performed to increase the opening of the flow rate adjustment valve in a step set in advance in step S17, and the flow rate of the primary-side hot water is increased. Return to start. Control for increasing or decreasing the opening degree of the flow rate adjusting valve is also performed stepwise, and the magnitude of the step is adjusted by the length of the piping path and the amount of water held by the piping path. While controlling the flow rate of cold water and hot water by increasing and decreasing the opening of the flow rate adjustment valve in this way, while performing pump control according to the heat customer identified as requiring the most circulating head, other customers It is possible to ensure the temperature difference between the inlet and outlet of the cold water and hot water of the heat exchanger. As a result, energy saving can be achieved.

  In the above embodiment, an example is shown in which the differential pressure between the inlet pressure and the outlet pressure of the primary side cold / hot water is directly measured using a differential pressure sensor. However, a pressure sensor for measuring the inlet pressure is installed in the forward path 4a. Alternatively, a pressure sensor that measures the outlet pressure may be installed in the return path 4b, and the controller may be configured to calculate the differential pressure from the outputs of both pressure sensors.

  Next, another embodiment of the water supply control system and the control method thereof according to the present invention will be described in detail with reference to FIGS. The block diagram of FIG. 4 shows a schematic configuration of the water supply control system according to the present embodiment, and the flowchart of FIG. 5 performs control to increase or decrease the rotational speed of the pump that supplies the cold / hot water of the water supply control system of FIG. In addition, control for adjusting the flow rate of the primary side cold / hot water by opening and closing the flow rate adjustment valve is shown. This embodiment is characterized in that, compared to the above-described embodiment, it is configured to measure the outgoing temperature of the primary side cold / hot water entering the heat exchanger and the return temperature coming out of the heat exchanger. In addition, about the structure substantially equivalent to embodiment mentioned above, the same referential mark is attached | subjected and detailed description is abbreviate | omitted.

  In FIG. 4, temperature sensors Ta1 and Tb1 are installed in the forward paths 4a and 4c for circulating the primary side cold / hot water to the heat exchangers 2A, 2B, and temperature sensors Ta2 and Tb2 are installed in the return paths 4b and 4d. ing. The outgoing temperature sensor measures the outgoing temperature of the primary cold / hot water entering the heat exchanger, and the return temperature sensor measures the return temperature of the primary cold / hot water coming out of the heat exchanger. . The measurement data of these four temperature sensors are input to the control device 8 and used for control of the inverter 7a and control of the flow rate adjusting valves V1, V2. Other configurations are substantially the same as those of the above-described embodiment.

  The operation of the present embodiment configured as described above will be described below with reference to FIG. The flow from step S1 to step S9 is the same as that of the above-described embodiment, and the description is omitted. In step S20, for example, in heat consumer A, for example, in heat customer A, the temperature sensor Ta1 installed in the outward path 4a and the return path 4b are compared with the heat consumer other than that specified as the heat consumer requiring the most circulating head in step 5. Using the measurement data with the temperature sensor Ta2 installed in the vehicle, a return temperature difference, which is a return temperature difference, is calculated, and the return temperature difference is compared with a preset set value. Thereafter, when the return temperature difference is greater than or equal to the set value, the valve opening is increased in step S21, and the primary cold / hot water flow rate is increased. When the difference is less than the set value, the valve opening is decreased in step S22. Reduce the flow rate of the side cold / hot water. Thus, the return temperature difference in each heat exchanger is calculated, the return temperature difference of each heat exchanger is compared with the set value, and when the return temperature difference is equal to or larger than the set value, the flow rate adjusting valves V1, V2 are set in step S21. When the opening degree is increased and the return temperature difference is less than the set value, the opening degree of the flow rate adjusting valves V1, V2 is decreased in step S22 to adjust the flow rate of the primary side cold / hot water.

  In this embodiment configured as described above, the outgoing temperature of the primary side cold / warm water entering the heat exchanger is normally set to be constant, but the temperature of the cold / warm water supplied from the heat source unit 1 is normal. Even if it is different from the temperature range of the heat exchanger, the controller calculates the optimum differential pressure using the map according to the heat demand of the measured heat exchanger and the heat demand prepared in advance. Stable control is possible without being affected by the temperature of the primary cold / hot water entering.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed. For example, although the example of one heat source machine was shown as a heat source machine, you may comprise using a plurality of heat source machines.

  Moreover, although the example of two heat consumers was shown as an example of a some heat consumer, of course, it can apply also in the case of three or more heat consumers. Furthermore, this invention is applicable also to the example which conveys the cold / hot water produced | generated from one heat-source equipment to the heat consumer for every floor in a building, for example in one building. Although the example of cold / hot water was shown as a heat medium which conveys heat energy, another medium can also be used. Furthermore, in calculating the heat demand of the heat exchanger, an example of calculating based on the measurement result on the secondary side has been described, but using the value measured on the primary side instead of the measurement on the secondary side Similarly, the heat demand amount of the heat exchanger may be calculated.

  As an example of use of the present invention, this water supply control system can be used to carry cold / hot water on the primary side of the heat exchanger with the minimum necessary power, and cold / hot water as a heat medium for a district cooling / heating device or a cooling / heating device in a building. It can also be applied to the purpose of transport.

  1: Heat source machine, 2A, 2B ...: Heat exchanger (load equipment), 3A, 3B ...: Heat utilization equipment, 4: Primary side conduit, 4a, 4c: Outward path, 4b, 4d: Return path, 5, 6 : Secondary side conduit, 5a, 6a: forward path, 5b, 6b: return path, 7: primary side pump, 7a: inverter, 8: control device, 8a: inverter control device, 8b: valve control device, 10, 11 : Differential pressure sensor, 12, 13: secondary pump, A, B, C ...: heat consumers, V1, V2: flow rate adjusting valve, F1, F2: flow rate sensor, T1, T2, T3, T4: temperature sensor , Ta, Tb, Ta1, Ta2, Tb1, Tb2: Temperature sensor

Claims (11)

The primary side cold / warm water generated by the heat source device is sent to a plurality of heat exchangers, and the heat energy of the primary side cold / warm water is transmitted to the secondary side cold / warm water via the heat exchanger to use a plurality of heats. A water supply control system for supplying equipment,
A primary-side pump that circulates primary-side cold / hot water between the heat source unit and the plurality of heat exchangers, an inverter that controls the rotation speed of the primary-side pump, and primary-side cold / hot water are supplied to the plurality of A plurality of primary-side flow rate adjusting valves that adjust the flow rate of the pipes that supply water to each of the heat exchangers, and the inlet / outlet pressures of the primary-side cold / hot water in the inlet and outlet pipes of the plurality of heat exchangers are detected. A pressure sensor, and a control device that adjusts the opening of the plurality of primary-side flow rate adjustment valves based on pressure data of the pressure sensor,
A plurality of secondary pumps for feeding secondary side cold / hot water between the plurality of heat exchangers and a plurality of heat utilization devices, a plurality of flow sensors for measuring the flow rates of the secondary side cold / warm water, A plurality of temperature sensors for measuring the temperature of the secondary side cold / hot water flowing into the plurality of heat exchangers and the temperature of the secondary side cold / hot water flowing out;
The control device identifies a heat consumer that needs the most circulation head from the output of each flow sensor and the data of each temperature sensor, and based on the identified heat consumer data, A water supply control system characterized in that the rotation speed is controlled by an inverter.   The control device calculates a heat demand of each heat utilization device on the secondary side of each heat exchanger, and calculates an appropriate flow rate of primary side cold / hot water to each heat exchanger from the calculated heat demand. Calculating the optimum differential pressure appropriate for each heat exchanger based on the flow rate, and identifying the heat consumer that most needs the circulation head from the difference between the optimum differential pressure and the actual differential pressure. The water supply control system according to claim 1, wherein   The control device compares a difference between an optimum differential pressure and an actual differential pressure of the plurality of heat consumers, and provides a heat consumer including a heat exchanger having a smallest difference between the differential pressure and the optimum differential pressure. 3. The heat consumer who needs the most circulating head is specified, and when the differential pressure in the heat exchanger is equal to or higher than the optimum differential pressure, the rotation speed of the primary pump is reduced by an inverter. The water supply control system described.   The water supply control system according to claim 2 or 3, wherein the control device calculates the optimum differential pressure from a map based on a flow rate of primary side cold / hot water appropriate for each calculated heat exchanger. . The water supply control system further includes a temperature sensor and a valve control device for measuring a return temperature of each primary side cold / hot water to the heat source unit,
The valve control device compares the return temperature of the temperature sensor with a set value, and increases the opening of the flow rate adjustment valve when the return temperature is equal to or higher than the set value during chilled water conveyance, and the return temperature is less than the set value. 5. The water supply control system according to claim 1, wherein the control is performed so that the opening degree of the flow rate adjusting valve is decreased at the time of the flow, and the reverse control is performed at the time of the hot water transfer. The water supply control system further includes a temperature sensor and a valve control device for measuring a temperature going into the heat exchanger of each primary side cold / hot water and a return temperature coming out of the heat exchanger,
The valve control device compares the return temperature difference between the return temperature and the return temperature of the temperature sensor with a set value, and increases the opening of the flow control valve when the return temperature difference is equal to or greater than the set value. It controls to water supply control system in any one of Claim 1 to 4 characterized by the above-mentioned. The primary side cold / warm water generated by the heat source unit is sent to a plurality of heat exchangers by a pump capable of controlling the rotation speed, and the heat energy of the primary side cold / warm water is transmitted to the secondary side cold / warm water via the heat exchanger. And a control method of a water supply control system that supplies a plurality of heat utilization devices,
On the secondary side of the heat exchanger, the heat demand of each thermal heat consumer is calculated from the inflow temperature, outflow temperature, and flow rate of the secondary side cold / hot water,
From the calculated heat demand, calculate the flow rate of the primary side cold / hot water required for the primary side heat exchanger,
From the calculated flow rate of the primary side cold / hot water, the optimum primary side differential pressure optimum for each heat exchanger is calculated,
Measuring a primary differential pressure flowing into and out of a primary side of the plurality of heat exchangers;
Based on the measured primary-side differential pressure of each heat exchanger and the primary-side optimum differential pressure, the heat consumer with the greatest demand for the circulation head is identified,
The flow rate adjustment valve for adjusting the flow rate of the primary side cold / hot water of the specified heat consumer is fully opened or the valve opening degree is opened to a predetermined value, and then the rotation speed of the primary side pump is changed by changing the rotation speed of the pump. A control method of a water supply control system, characterized by changing.   The method for controlling a water supply control system according to claim 7, wherein the step of calculating the optimum primary differential pressure optimum for each heat exchanger is performed using a map.   The control method of the water supply control system according to claim 7 or 8, wherein the rotational speed of the pump is decreased when the primary-side differential pressure is equal to or greater than the primary-side optimum differential pressure.   The control method of the water supply control system includes the flow rate when the return temperature of the primary side cold / hot water is equal to or higher than a set value as a process for heat consumers other than the heat consumer identified as having the highest demand for the circulation head. The water supply control according to any one of claims 7 to 9, wherein the opening of the regulating valve is increased and the opening of the flow regulating valve is decreased when the return temperature is lower than a set value. How to control the system.   The control method of the water supply control system is a process for a heat consumer other than the heat consumer specified as having the largest demand for the circulating head, when the return temperature difference of the primary side cold / hot water is a set value or more. 10. The control according to claim 7, wherein the opening degree of the flow rate adjusting valve is increased, and the opening degree of the flow rate adjusting valve is controlled to be decreased when the return temperature difference is less than a set value. Control method of water supply control system.

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