JP2010002158A - Control method of air conditioner and air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control method of an air conditioner capable of returning cold water (or hot water) to a heat source machine while the temperature difference of the cold water (or hot water) is sufficiently secured, and thus, to achieve reduction in pump carrying power and improvement of efficiency-performance coefficient COP of the heat source machine. <P>SOLUTION: In the control method of the air conditioner, changing characteristics of a flow ratio and an air conditioning load factor of heat exchangers approximate to a linear function. The heat exchangers are constituted to form multiple stages, and by operating all the heat exchangers, the full load time flow rate of cold water (or hot water) of the heat exchangers during full load can be secured. By stopping the cold water (or hot water) made to flow in any one of the multistage heat exchangers accompanying reduction in the air conditioning load, the operation of the one heat exchanger is stopped. A control valve is controlled so that the flow rate of the operated heat exchangers other than the stopped heat exchanger becomes a state of the maximum flow ratio of these heat exchangers. After any one of the heat exchangers is stopped, the control is performed so that the indoor temperature becomes set temperature by increasing/reducing the flow rate of the operated heat exchangers. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an air conditioner control method and an air conditioner suitable for use in air conditioning equipment such as a water-type central heat source system.

  Prior art document information relating to this type of air conditioning equipment includes the following (Patent Document 1, Patent Document 2).

  Conventionally, as shown in FIG. 8, a heat exchanger (cold water coil or hot water coil or cold / hot water coil) 56 is built in the air conditioner 53, and the heat exchanger 56 is cold water (or hot water) from a water-type central heat source system. The outgoing pipe 62 and the return pipe 63 are connected. Indoor air and outside air are supplied to the heat exchanger 56 by the blower fan 81, and the air 96 that has passed through the heat exchanger 56 is supplied with heat to the room as cold air (or warm air).

  The heat exchanger 56 of this type of air conditioner 53 is a single stage without being divided, and only one control valve 86 is provided. The air conditioner 53 performs flow rate increase / decrease control of the control valve 86 for cold water (or hot water) according to the indoor temperature detected by the indoor temperature detection sensor 73 or the supply air temperature detected by the supply air temperature detection sensor 74 or the request for dehumidification. ing.

  Therefore, for example, when the air conditioner is in the cooling operation, the control valve 86 is opened simultaneously with the operation, and the chilled water is circulated and supplied to the heat exchanger 56, and the temperature difference between the set temperature and the room temperature or the set temperature. The control valve 86 is controlled to open and close according to a temperature difference between the air supply temperature and the supply air temperature.

  And if room temperature falls below preset temperature by cold air blowing, the temperature will be detected, cooling capacity will be made small by reducing the amount of cold water to the heat exchanger 56, and room temperature will be maintained at preset temperature.

JP 2004-125316 A JP 2008-20168 A

However, in the above control method, for example, in the case of cooling, since there is a sufficient cooling load on the air side during the daytime in the summer, a sufficient temperature difference between the return temperature and the return temperature of the cold water is ensured. In the intermediate and winter seasons (in the region where the air conditioning load factor is 75% or less in the “air conditioning load factor vs. heat exchanger flow ratio characteristics” in FIG. 2), the cooling load on the air side is reduced. Although the temperature of the incoming air 96 decreases or the supply air temperature after passing through the heat exchanger increases, the chilled water circulating through the heat exchanger is reduced by the control valve 86 (broken line (ii) in FIG. 2). (Refer to the flow ratio in (b)), the temperature difference between the going temperature and the return temperature is not sufficiently secured, and the temperature is returned to the heat source unit of the water type central heat source system. As a result, the flow rate of the cold water (or hot water) cannot be sufficiently reduced with respect to the reduction of the cooling load, and the conveyance power of the cold water (or hot water) pump that circulates the cold water (or hot water) to the heat exchanger 56 is increased. As a result, the efficiency of the heat source equipment and the coefficient of performance COP are reduced. As a result, in the air conditioner using the conventional heat exchanger, as shown by the broken line in FIG. 2, there is a tendency that the flow rate ratio of the heat exchanger does not sufficiently decrease even when the air conditioning load factor decreases.
Since the apparatus of Patent Document 1 has a single heat exchanger and only opens and closes the corresponding control valve when the return water temperature is lowered, there is a problem similar to that of the above-described conventional technique (refer to “Document 1”, “0020”). "Column). When the cooling load decreases in the intermediate period and the winter period, the apparatus of Patent Document 2 bypasses the low temperature outside air without passing through the heat exchanger, so that the temperature difference between the forward temperature and the return temperature in the heat exchanger is reduced. However, since the heat exchanger is independent, there is a problem similar to the above-described conventional one.

  The present invention has been made in view of the above-described conventional situation, and provides an air conditioner that can return water to a heat source unit while sufficiently ensuring a temperature difference between cold water (or hot water) and a method for controlling the air conditioner. The purpose is to reduce the conveyance power of the pump and improve the efficiency and coefficient of performance COP of the heat source machine.

In order to achieve the above object, the present invention
First, the heat exchanger in the air conditioner is divided into two (6, 7), and cold water (or hot water) is recirculated and supplied to the two divided heat exchangers (6, 7). A control method of an air conditioner for exchanging heat by passing a mixed air (46, 47) of indoor air and outside air through an exchanger (6, 7), wherein the divided heat exchanger (6, 7) A control valve (36, 37) is installed in each return pipe or outgoing pipe, and the heat exchanger (6, 7) is provided for each heat exchanger (6, 7) by the control valve (36, 37). The amount of cold water (or hot water) that passes through is configured to be able to increase / decrease or stop completely, and the indoor temperature or supply air temperature is detected so that the indoor temperature or supply air temperature becomes the set temperature, and cold water (or hot water) Each heat exchanger is opened and closed by opening and closing each control valve (36, 37) of the heat exchanger (6, 7). 6, 7) Increase or decrease control of the cold water (or hot water) passing through to control the room temperature or the supply air temperature constant, and further the temperature of the cold water (or hot water) going to each of the heat exchangers (6, 7) (T11), the return temperature (T12), and the amount of heat detected based on the flow rate (Q) passing through each heat exchanger (6, 7), and the amount of heat determined by the number of divisions for the full load In this case, one of the control valves (36, 37) installed in the divided heat exchanger (6, 7) (for example, 37) is fully closed, and the other control valves (36) By increasing the flow rate so that the flow rate is lower than the total flow rate of the two heat exchangers, control is performed so as to ensure a temperature difference between the forward temperature and the return temperature, while any one of the control valves (37) is controlled. After closing, the indoor air and the outside air after heat exchange input to the air conditioner are connected to the control valve (37 In the heat exchanger (6) in which the circulation of cold water (or hot water) is stopped, the heat is not exchanged in the heat exchanger (7), and in the heat exchanger (6) in which the cold water (or hot water) is recirculated. Heat is exchanged air, the two air are mixed and air is supplied to the room, and in this state, the cold water (or hot water) is circulated so that the room temperature or the supply air temperature becomes the set temperature. The control valve (36) of the exchanger (6) is used to control the increase or decrease of cold water (or hot water).

  The amount of heat processed by the air conditioner can be obtained by calculation based on, for example, the equation (1) (heat amount Q [kW] = flow rate M [L / h] × (T12−T11) [° C.] × specific heat). 21). Full load means that all of the divided heat exchangers are operating at the maximum heat amount that can be processed (air conditioning load factor 100%, heat exchanger flow rate ratio 100%). The set value in which the amount of heat is determined by the number of divisions for the full load is when, for example, the heat amount is reduced to ½ or less with respect to the full load. Can be set as a set value. The flow rate of the other control valve (36) is increased to a flow rate lower than the total flow rate of the two heat exchangers. Is closed, and the heat exchanger (6) corresponding to the non-closed control valve is operated at the maximum flow rate ratio.

  Secondly, in the control method for an air conditioner according to the first aspect, the amount of heat is detected based on the temperature of the cold water (or hot water) sent to each heat exchanger, the return temperature, and the flow rate passing through each heat exchanger. When the amount of heat reaches the set value determined by the number of divisions for the full load, instead of the control for fully closing any one of the control valves installed in the divided heat exchanger, the indoor air When the temperature difference (t1-t2) is measured by detecting the mixed air temperature and the supply air temperature of the outside air and the temperature difference becomes the set value determined by the number of divisions for all loads, The control method of the air conditioner is characterized by performing control to fully close any one of the control valves installed in the divided heat exchanger.

  The temperature difference between the mixed air and the supply air can be obtained by calculation based on, for example, the equation (2) (temperature difference Δt [° C.] = T 1 -t 2 [° C.]), and can be calculated by the controller (21), for example. . Full load refers to a state where all of the divided heat exchangers are operating at the maximum temperature difference that can be processed (air conditioning load factor 100%, heat exchanger flow rate ratio 100%). The set value in which the temperature difference is determined by the number of divided stages with respect to the full load is, for example, a state such as an intermediate period in which the temperature difference is reduced to 1/2 or less with respect to the full load. When the temperature difference is ½ or less, the set value can be set.

  Thirdly, the heat exchanger in the air conditioner is divided into two or more n stages (n is an integer of 2 or more), and cold water (or hot water) is circulated and supplied to the divided n stages of heat exchangers. A control method for an air conditioner that exchanges heat by passing room air and outside air through these heat exchangers, wherein the heat exchanger is divided into n stages, and a return pipe or an outgoing pipe for each divided heat exchanger Each control valve is provided with a control valve, and the amount of cold water (or hot water) passing through the heat exchanger for each heat exchanger can be increased, decreased, or completely stopped by these control valves, and the room temperature or the supply air temperature Chilled water that passes through each heat exchanger by detecting the room temperature or the supply air temperature so that the temperature becomes the set temperature and opening and closing each control valve of the heat exchanger in which the chilled water (or hot water) is circulated ( (Or hot water) is controlled to increase or decrease the room temperature, and further to the heat exchanger. The amount of heat is detected from the degree, return temperature, and flow meter, and every time the amount of heat reaches the set value determined by the number of divisions for all loads, one of the above control valves is fully closed and the other The flow rate of the control valve is increased to reduce the flow rate corresponding to 1 / n with respect to the total flow rate at full load, thereby controlling the temperature difference between the return temperature and the return temperature. On the other hand, after fully closing any one of the control valves, the heat exchanger in which the indoor air and the outside air after heat exchange input to the air conditioner are stopped from circulating cold water (or hot water) by the control valve. In this state, the air is not heat-exchanged in the air, and the air is heat-exchanged in the heat exchanger in which the cold water (or hot water) is circulated. Cool water (or hot water) is circulated so that the room temperature or the supply air temperature becomes the set temperature. Constituted by the control method of the air conditioner, characterized in that the to and the heat exchanger of the control valve to increase or decrease control of cold water (or hot water).

  The n stage is an integer of 2 or more, preferably an integer of 2 or more and 8 or less. When the amount of heat becomes a set value determined by the number of stages of division, for example, when the amount of heat decreases to 1 / n or less with respect to the full load (the maximum heat amount that can be processed by the air conditioner), that is, divided for the entire load. When the heat load divided by the number of heat exchangers (n) is reduced, for example, when divided into three stages, when the amount of heat treated is 2/3 of the maximum heat amount that can be treated, and Each of the cases where the amount of heat processed becomes 1/3 of the maximum heat amount that can be processed. The state in which the flow rate corresponding to 1 / n is reduced with respect to the flow rate at the full load (flow rate ratio 100%) is the heat exchange during operation by the non-closed control valve after closing any control valve. The state where the flow rate ratio of the heat exchanger is maximized, and the state where the flow rate is reduced from the total flow rate of the n-stage heat exchanger. For example, in the case where the heat exchanger is divided into three stages, when the processing heat amount becomes 2/3 of the maximum heat amount that can be processed, the flow rate corresponding to 1/3 is reduced, and as a result, the total flow rate is 2 / 3, and when the heat of treatment becomes 1/3 of the maximum heat that can be processed, the flow corresponding to 1/3 is further reduced, resulting in a flow of 1/3 of the total flow. I do.

  In this air conditioner control method, the heat exchange heat quantity is detected by the cold water (or hot water) temperature and flow rate of the outgoing pipe and return pipe. For example, in the case of two divisions, the heat exchanger that divides the heat quantity that can be processed by this air conditioner When the value is equal to or less than the value divided by the number 2, the chilled water in the heat exchanger that stopped circulation (or Heat exchange between hot water and air stops. As a result, the flow rate of cold water (or hot water) is ½ or less, but heat exchange of a necessary amount of heat is concentrated and performed only with a heat exchanger in which a control valve that is not fully closed is installed. The heat exchange with the indoor air or the outside air can be sufficiently performed, the required proper heat exchange is ensured, and a sufficient temperature difference between the outgoing pipe and the return pipe is always secured. As a result, the amount of cold water (or the amount of hot water) is controlled to a small amount of water, and the pumping power of the pump can be reduced, the efficiency of the heat source machine, and the coefficient of performance COP can be improved.

  Fourthly, in the control method for an air conditioner described in the third aspect, the amount of heat is detected from the temperature going back to the heat exchanger, the return temperature and the flow meter, and the amount of heat is determined by the number of divisions for the full load. Instead of the control to fully close any one of the control valves every time the set value is reached, the temperature difference is measured by detecting the mixed air temperature and the supply air temperature of the indoor air and the outside air, and the full load Each time the temperature difference becomes a set value determined by the number of divisions, control is performed to fully close any one of the control valves.

  When the temperature difference becomes a set value determined by the number of divisions, for example, when the temperature difference decreases to 1 / n or less with respect to the full load (the maximum temperature difference that can be processed by the air conditioner), that is, to the full load. The degree to which the heat load divided by the number of divided heat exchangers (n) is reduced. For example, when divided into three stages, the temperature difference becomes 2/3 of the maximum processable temperature difference. , And when the processing temperature difference is 1/3 of the maximum temperature difference that can be processed.

  In this air conditioner control method, the temperature difference is detected from the mixed air temperature and the supply air temperature. For example, in the case of two divisions, the temperature difference that can be processed by this air conditioner is equal to or less than the value divided by the number of divided heat exchangers. Then, by completely closing any one of the control valves attached to the divided heat exchangers, heat exchange between cold water (or hot water) and air in the heat exchanger that stopped circulation Stops. As a result, the flow rate of cold water (or hot water) is ½ or less, but heat exchange of a necessary temperature difference is concentrated and performed only by a heat exchanger provided with a control valve that is not fully closed. Therefore, heat can be sufficiently exchanged with room air or outside air, the required proper heat exchange is ensured, and a sufficient temperature difference between the outgoing pipe and the return pipe is always secured. As a result, the amount of cold water (or the amount of hot water) is controlled to a small amount of water, and the pumping power of the pump can be reduced, the efficiency of the heat source machine, and the coefficient of performance COP can be improved.

  Fifth, the heat exchanger in the air conditioner is divided into two or more n stages (n is an integer of 2 or more), and a control valve is installed in each return pipe or outgoing pipe for each divided heat exchanger, The cooling water (or hot water) is recirculated and supplied to the heat exchanger of the air conditioner, and the indoor air and the outside air are passed through the heat exchanger, so that heat is exchanged between the cold water (or hot water) and the air. In addition, an outgoing pipe temperature sensor is installed in the outgoing pipe common to the heat exchangers, a return pipe temperature sensor and a flow meter are installed in the return pipe common to the heat exchangers, and Is provided with a supply air temperature sensor or a room temperature sensor, and further detects the detection temperature of the supply air temperature sensor or the room temperature sensor, the detection temperature of the forward pipe temperature sensor and the return pipe temperature sensor, the detection flow rate of the flow meter, Controller capable of opening / closing each control valve The controller recognizes the detected temperature of the supply air temperature sensor or the indoor temperature sensor, and controls the opening and closing of the control valve so that the detected temperature becomes a set value, and the forward pipe The calorific value calculating means for calculating the calorific value based on the detected temperature of the temperature sensor, the detected temperature of the return pipe temperature sensor, and the detected flow rate, and that the calorific value of the calorific value calculating means has become 1 / n or less at full load. Control valve closing means for completely closing any one of the operating control valves each time it is detected and stopping the circulation of the cold water (or hot water) of the corresponding heat exchanger, And a flow rate control means for controlling opening and closing of the operating control valve so that the flow rate of the operating heat exchanger is reduced by 1 / n with respect to the flow rate at the time of full load together with the control valve being fully closed. The air conditioner is characterized by It is.

  In this air conditioner, the amount of heat consumed by the air conditioner is detected by a temperature sensor that detects the cold water (or hot water) temperature of the outgoing pipe and the return pipe, and a flow meter that detects the flow rate of the outgoing pipe (or the outgoing pipe). Thus, the heat exchangers divided into two or more multi-stages were divided into multi-stages by increasing or decreasing the amount of cold water (or hot water) by the control valve installed for each heat exchanger or total stop control Some of the heat exchangers are passed through without heat exchange with room air and outside air. On the other hand, in a heat exchanger different from a fully-closed heat exchanger, sufficient heat exchange is performed, and the cooling (or heating) capacity of the chilled water (or hot water) to be circulated is fully extracted, so It is controlled so as to ensure a sufficient temperature difference between the temperature and the return temperature.

  Sixth, the heat exchanger in the air conditioner is divided into two or more n stages (n is an integer of 2 or more), and a control valve is installed in each return pipe or outgoing pipe for each divided heat exchanger, The cooling water (or hot water) is recirculated and supplied to the heat exchanger of the air conditioner, and the indoor air and the outside air are passed through the heat exchanger, so that heat is exchanged between the cold water (or hot water) and the air. A mixture air temperature sensor for indoor air and outside air is provided on the inlet side of the heat exchanger, and a supply air temperature sensor or an indoor temperature sensor is provided in a room to be supplied, and the mixed air temperature sensor and the supply air A controller capable of recognizing the temperature detected by the temperature sensor or the indoor temperature sensor and controlling the opening and closing of each control valve is provided, the controller recognizes the temperature detected by the air supply temperature sensor or the room temperature sensor, and detects the detected temperature. An indoor temperature setting means for controlling the opening and closing of the control valve so as to be a set value; and a temperature difference calculating means for calculating a temperature difference between the detected temperatures of the two sensors based on the detected temperatures of the mixed air temperature sensor and the supply air temperature sensor And every time it detects that the temperature difference of the temperature difference calculation means has decreased by 1 / n with respect to the temperature difference at the time of full load, it fully closes one of the operating control valves. With the control valve closing means for stopping the circulation of cold water (or hot water) in the corresponding heat exchanger and the full closing of any one control valve, the flow rate of the operating heat exchanger becomes the flow rate at full load On the other hand, it comprises an air conditioner characterized by comprising flow rate control means for controlling opening and closing of a control valve that is operating so as to decrease by 1 / n.

  This air conditioner is divided into two or more multi-stages by detecting the temperature difference that is lowered (or raised) by the air conditioner by the temperature sensor that detects the mixed air temperature of the room air and the outside air and the supply air temperature. Each of the heat exchangers is designed to increase or decrease the amount of cold water (or hot water) using a control valve installed for each heat exchanger, or to stop all of the heat exchangers. Pass through air and outside air without heat exchange. On the other hand, in a heat exchanger different from a fully-closed heat exchanger, sufficient heat exchange is performed, and the cooling (or heating) capacity of the chilled water (or hot water) to be circulated is fully extracted, so It is controlled so as to ensure a sufficient temperature difference between the temperature and the return temperature.

  Seventhly, after the indoor temperature setting means has closed any of the control valves, the control valve corresponding to the operating heat exchanger is controlled to open and close to maintain the room temperature constant. 8. The air conditioner according to the sixth or seventh feature.

  Eighth, by using an air conditioner whose change characteristics of the flow rate ratio and the air conditioning load factor of the heat exchanger approximate to a linear function, the heat exchanger is controlled to open and close by controlling the opening and closing of the control valve of the heat exchanger. Is a control method of an air conditioner that controls the supply air temperature or the room temperature to be a set temperature by increasing or decreasing the flow rate of cold water (or hot water) flowing through the heat exchanger. By configuring the heat exchanger to ensure a full load flow rate of chilled water (or hot water) of the heat exchanger at full load, the chilled water flowing in any one of the multi-stage heat exchangers (or When the air conditioning load decreases, the operation of the heat exchanger is stopped and the flow rate of the heat exchangers other than the stopped heat exchanger is equal to the maximum flow rate ratio of those heat exchangers. After controlling the control valve to be in a state and stopping any of the above heat exchangers, Constituted by the control method of the air conditioner and the controller controls so that the supply air temperature or the indoor temperature reaches the set temperature by increasing or decreasing the flow rate of the heat exchanger Sakuchu.

  According to the control method of an air conditioner and the air conditioner according to the present invention, the indoor temperature or the supply air temperature is detected, and the amount of cold water (or hot water) passing through the heat exchanger is controlled to increase or decrease, while the forward temperature and the return temperature And by calculating the amount of heat treated by detecting the flow rate and fully closing any of the control valves installed for each heat exchanger, it is divided into a heat exchanger that exchanges heat with air and a heat exchanger that does not exchange heat, By reducing the flow rate of the entire air conditioner, the heat exchanger that exchanges heat can sufficiently exchange heat, and as a result, a sufficient temperature difference between the outgoing pipe and the return pipe can be secured. As a result, the pump power can be reduced and the efficiency and coefficient of performance COP of the heat source machine can be improved.

  In addition, according to the control method and the air conditioner of the air conditioner according to the present invention, the processing temperature difference is calculated by detecting the mixed air temperature and the supply air temperature of the indoor air and the outside air, and the control installed for each heat exchanger By fully closing any of the valves, heat exchangers that exchange heat with air are divided into heat exchangers that do not exchange heat, and heat exchangers that exchange heat by reducing the flow rate of the entire air conditioner are sufficient. As a result, a sufficient temperature difference between the outgoing pipe and the return pipe can be secured. As a result, the pump power can be reduced and the efficiency and coefficient of performance COP of the heat source machine can be improved.

  Hereinafter, preferred embodiments of an air conditioner control method and an air conditioner according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a configuration diagram showing an outline of an air conditioner (a multistage heat exchanger / cold water (or hot water) return temperature difference securing air conditioner) using an embodiment of the present invention.

  The air conditioner 3 according to the present embodiment includes a heat exchanger divided into two or more multistages. FIG. 1 shows a case of a two-stage system divided into two, and chilled water (or hot water) is circulated and supplied to the heat exchanger 6 and the heat exchanger 7, and the heat exchanger 6 and the heat exchanger 7 are almost equally distributed. By passing the room air (return air RA) and the outside air (OA), the cold water (or hot water) is exchanged with the room air and the outside air. In addition, these heat exchangers 6 and 7 are comprised by the cold water coil, the hot water coil, or the cold / hot water coil.

  The heat exchanger 6 and the heat exchanger 7 are connected to a cold water (or hot water) forward pipe 12 and a cold water (or hot water) return pipe 13 from a water-type central air conditioning system (heat source equipment such as a refrigerator and a boiler). . The air conditioner 3 has a built-in blower fan 31, which sucks indoor air and outside air, passes the heat through the heat exchanger 6 and the heat exchanger 7, exchanges heat, and cool air (or hot air). Blow out the air. Further, the blower fan 31 can be variably controlled in the amount of blown air, for example, by an inverter controller 32 or the like.

  A control valve 36 is attached to the return pipe of the heat exchanger 6, and a control valve 37 is attached to the return pipe of the heat exchanger 7, and the heat exchangers 6 and 7 connected to the heat exchanger 6 and the heat exchanger 7 are common. The outgoing pipe temperature sensor 26 is attached to the outgoing pipe 12, and the return pipe temperature sensor 27 and the flow meter 33 are attached to the return pipe 13 common to the heat exchangers 6 and 7. 27 and the detection signal from the flow meter 33, the controller 21 detects the amount of heat to be exchanged between the heat exchanger 6 and the heat exchanger 7.

  The control valve 36 and the control valve 37 can be controlled steplessly. That is, the control valve 36 and the control valve 37 pass through the heat exchanger 6 and the heat exchanger 7 so that the room temperature (the room temperature sensor 25) or the supply air temperature (the supply air temperature sensor 24) becomes the set temperature. The amount of cold water (or hot water) to be controlled is increased or decreased. Further, in the case of a two-stage heat exchanger divided into two, for example, the air conditioner 3 is detected by the outgoing pipe temperature sensor 26, the return pipe temperature sensor 27, and the flow meter 33, and the amount of heat is calculated by the controller 21. When the maximum heat quantity that can be processed becomes less than 1/2, or the temperature is detected by the temperature sensor 23 and the supply air temperature sensor 24 of the mixed air of the outside air (OA) and the return air (RA), the mixed air and the supply air temperature When the temperature difference between the control valve 36 and the control valve 37 reaches a predetermined value, either the control valve 36 or the control valve 37 is fully closed, and the circulation of cold water (or hot water) in the corresponding heat exchanger is stopped. And the circulation amount of cold water (or hot water) is controlled only by the other control valve so that the room temperature or the supply air temperature becomes the set temperature.

  The control based on the heat quantity and the control based on the temperature difference are performed by selecting either one.

  The control valve 36 and the control valve 37 perform control so that the temperature detected from the indoor temperature sensor 25 or the supply air temperature sensor 24 is maintained at the set temperature. This control is realized by inputting detection signals from the mixed air temperature sensor 23, the indoor temperature sensor 25, the supply air temperature sensor 24, the outgoing pipe temperature sensor 26, the return pipe temperature sensor 27, and the flow meter 33 to the controller 21. .

  Therefore, in the heat exchanger 6 and the heat exchanger 7, when the total air volume passes, heat exchange of the maximum heat quantity that can be processed is performed, and the rated forward temperature, return temperature, and temperature difference are secured.

  In the air conditioner 3, indoor air (returned air RA) and outside air (OA) are passed through the heat exchanger 6 and the heat exchanger 7 almost evenly through a two-stage heat exchanger divided into two. Therefore, the air that has passed through the heat exchanger 6 and the air that has passed through the heat exchanger 7 out of the air sucked into the air conditioner 3 are mixed and then supplied to the room via the blower fan 31.

  At this time, when either the control valve 36 or the control valve 37 is fully closed, the heat-exchanged air and the non-heat-exchanged air are mixed and supplied to the room. An indoor temperature sensor 25 is provided in the room. An air supply temperature sensor 24 for detecting the air supply temperature is provided in the vicinity of the air outlet of the air conditioner 3.

  In the heat exchanger in which the indoor air and the outside air are divided into two or more in the multi-stage heat exchanger air conditioner 3, a method of mixing heat exchanged air and air that does not exchange heat is used in the general air conditioner 53. Thus, the cooling and dehumidifying capacity is higher than the method of passing through the heat exchanger 56 that uniformly heat-exchanges all the air, and this method has an effect of reducing reheating.

Next, the operation of the air conditioner 3 having such a configuration will be described.
FIG. 2 is a change characteristic of the flow ratio of the heat exchanger and the air conditioning load factor, and a linear function indicated by a thin solid line shows an ideal flow ratio change characteristic with the highest efficiency. The present invention realizes an air conditioner having a change characteristic approximating this linear function by providing a heat exchanger having two or more stages. In the characteristic diagram of FIG. 2, the flow rate is the difference between the most efficient forward temperature and return temperature of the refrigerator and the flow rate with respect to the maximum cooling heat amount at the maximum cooling load in the summer cooling. The flow rate is 100% of the "heat exchanger flow rate ratio" (maximum flow rate ratio). The maximum cooling load at that time is set to 100% of the “air conditioning load factor”. Similarly, in the case of heating in winter, when the temperature difference and flow rate between the most efficient forward temperature and return temperature of the refrigerator are compared to the maximum heat amount at the maximum load in heating, the flow rate is referred to as the heat exchanger flow rate. The flow rate is 100% of the “ratio”, and the maximum load at that time is 100% of the “air conditioning load factor”.

  Further, the case where the air conditioning load factor is 100% and the flow rate is 100% (point a in FIG. 2) is referred to as “maximum flow rate ratio”. In addition, when the “maximum flow rate ratio” is captured for each heat exchanger, when the heat exchanger is divided into multiple stages, for example, when the heat exchanger is divided into two stages, the maximum flow rate ratio for each heat exchanger is 50% each (point b in FIG. 2), when divided into three stages, the maximum flow rate ratio of each heat exchanger is 33% (points b ′ and c ′ in FIG. 6), and each heat exchanger It is assumed that a maximum flow rate ratio of 100% for the entire air conditioner is secured.

  Among the heat exchangers divided into two or more multistages according to the present invention (see FIG. 2), as an assumed value in the case of a two-stage heat exchanger divided into two, at low load or partial load The flow rate ratio of cold water (or hot water) flowing through the heat exchanger 6 provided with the control valve 36 that is not fully closed is “one-dot chain line”, and the heat exchanger 7 provided with a control valve that is fully closed when the load is low. The flow rate ratio of the flowing cold water (or hot water) is “two-dot chain line”, the total flow rate ratio of the heat exchanger 6 and the heat exchanger 7 is “thick solid line”, and further flows through the heat exchanger 56 of the general air conditioner. The flow rate ratio of cold water (or hot water) is indicated by “broken line”.

  Here, although the two-stage heat exchanger of the present invention and the heat exchanger of the general air conditioner have a sufficient temperature difference between the return temperature and the return temperature at an air conditioning load factor of 100%, the heat exchange is divided into two parts. Assuming that the minimum required flow ratio of one heat exchanger of the heat exchanger is 30% (1/2 of the minimum required flow ratio of one conventional heat exchanger 56), at the flow ratio of 30%, the forward temperature and the return temperature are It is assumed that only 50% of the temperature difference is secured.

  Therefore, the flow rate ratio of the heat exchanger 56 of the general air conditioner is as follows. The flow rate ratio is 100% (maximum flow rate ratio) when the air conditioning load factor is 100%, the flow rate ratio is 70% when the air conditioning load factor is 50%, and the flow rate ratio when the air conditioning load factor is 30%. 60% (see broken line in FIG. 2).

  On the other hand, in the case of a two-stage heat exchanger, when the air conditioning load factor is 100%, a total of 100% of the flow ratio 50% (maximum flow ratio) of the heat exchanger 6 and the flow ratio 50% (maximum flow ratio) of the heat exchanger 7 is 100. %, And the air conditioning load factor 50%, the flow rate ratio 35% of the heat exchanger 6 and the flow rate ratio 35% of the heat exchanger 7 total 70%, which is assumed to be simultaneous with the general air conditioner.

  However, for example, when the air conditioning load factor is 49%, the flow rate ratio of 49% of the heat exchanger 6 and the flow rate ratio of the heat exchanger 7 is 49%, and when the air conditioning load factor is 30%, the flow rate ratio of the heat exchanger 6 is 40%. A total of 40% of the flow rate ratio 0% of the heat exchanger 7 is obtained, and a sufficient flow rate difference can be secured by reducing the flow rate by a small amount of water (20% reduction) compared to 60% of the general air conditioner. Furthermore, since the minimum required flow rate is halved, control is possible up to a minimum flow rate ratio of 30% and an air conditioning load factor of 15%.

  The multi-stage heat exchange air conditioner shown in FIG. 2 shows the flow rate ratio of the two-stage heat exchanger for simplification of explanation, and the number of stages increases as the number of stages increases to three-stage and four-stage. Ensuring the temperature difference between the temperature and the return temperature is even more reliable.

  The controller 21 is actually a control means including a CPU. The CPU controls the opening and closing of the control valves 36 and 37 according to the operation procedure shown in FIGS. 4 to 6, and the function thereof is shown in FIG. It is shown as a functional block diagram. The room temperature setting means 21a in the controller 21 receives temperature detection signals from the mixed air temperature sensor 23, the supply air temperature sensor 24 or the room temperature sensor 25, and compares these detection signals with a set value (set temperature). If the detected temperature is higher (or lower) than the set temperature as a result of the comparison, the control valve 36 and the control valve 37 are opened to increase the flow rate of cold water (or hot water) and pass through the heat exchangers 6 and 7. When the detected temperature is lower (or higher) than the set temperature, the control valve 36 and the control valve 37 are squeezed to cool water (or hot water). The flow rate of the air is reduced, and the temperature of the air 46 and 47 passing through the heat exchangers 6 and 7 is controlled to increase (or decrease) to maintain the room temperature constant. In addition, after the control valve 37 is fully closed, the room temperature setting means 21a performs an operation of controlling the room temperature to be constant by performing opening / closing control of only the control valve 36.

  The calorific value calculation means 21b receives the temperature detection signal T11 of the outgoing pipe temperature sensor 26, the temperature detection signal T12 of the return pipe temperature sensor 27, and the flow rate detection signal from the flow meter 33, and calculates the processing heat quantity Q by the following equation. Perform the operation.

Heat quantity Q [kW] = flow rate M [L / h] × (T12−T11) [° C.] × specific heat (1)
Then, it is determined whether or not the heat quantity Q is ½ or less of the maximum heat quantity Qmax that can be processed by the air conditioner 3 (air conditioning load factor 100%), and the heat quantity calculation means 21b determines the maximum heat quantity Qmax that can be processed. When it is detected that the ratio has become ½ or less, the control valve closing means 21c performs an operation of fully closing the control valve 37. Further, when the calorific value calculating means 21b detects that the processing heat quantity becomes 1/2 of the maximum heat quantity Qmax that can be processed, the flow rate control means 21d increases the flow rate of the control valve 36 at the same time, thereby increasing the maximum heat exchanger 6 capacity. The capacity operation state (maximum flow rate ratio state) is assumed.

When the control is performed based on the temperature difference instead of the heat amount, the heat amount calculation unit 21b functions as a temperature difference calculation unit and performs the following control. The temperature difference calculating means 21b receives the temperature detection signal t1 of the mixed air temperature sensor 23 of the indoor air and the outside air and the temperature detection signal t2 of the supply air temperature sensor 24, and calculates the processing temperature difference Δt by the following equation. .
Temperature difference Δt [° C.] = T 1 −t 2 [° C.] (2)
The temperature difference Δt becomes 1/2 (Δt = 7.5 ° C. to 8 ° C.) of the maximum temperature difference Δtmax that can be processed by the air conditioner 3 (air conditioning load factor 100%, for example, Δt = 15 ° C. to 16 ° C.). When the temperature difference calculating means 21b detects that the processing temperature difference is ½ or less of the maximum processable temperature difference Δt, the control valve closing means 21c controls the control valve 37 to be fully closed. Is to do. When the temperature difference calculating means 21b detects that the processing temperature difference is ½ of the maximum processable temperature difference Δtmax, the flow rate control means 21d simultaneously increases the flow rate of the control valve 36, and the heat exchanger 6 is the maximum capacity operation state (maximum flow rate state).

  In either case of controlling by the amount of heat and controlling by the temperature difference, the indoor temperature setting means 21a thereafter controls the control valve 36 based on the detection signal from the supply air temperature sensor 24 or the indoor temperature sensor 25. Only the opening / closing control is performed to control the room temperature to be constant.

  Next, the operation of the air conditioner according to the present invention will be specifically described based on the flowcharts of FIGS.

  Between the air conditioning load factors of 100% to 50% (region (C) in FIG. 2), the control valves 36 and 37 are both open and controlled to be opened and closed by the controller 21 (indoor temperature setting means 21a). That is, the controller 21 (room temperature setting means 21a) detects the room temperature sensor 25 and the supply air temperature sensor 24, and determines whether the room temperature is at the set value or whether the supply air temperature is at the set value. (P1 and P2 in FIG. 4), if not in the set value, the control valve 36 and the control valve 37 are controlled to open and close to control the flow rates of the heat exchanger 6 and the heat exchanger 7 (FIG. 4P3). The temperature of the air passing through the heat exchangers 6 and 7 is lowered or raised, and the room temperature is controlled to be a set value (constant).

  For example, assuming that the mixing temperature of the return air 46 and the outside air 47 is 30 ° C. and the cold water temperature of the outgoing pipe 12 is 7 ° C. at the maximum load such as midsummer, the return air 46 and the outside air 47 are the heat exchangers 6 and 7. It is cooled to 15 ° C. to 16 ° C. and supplied to the room by the blower fan 31. The temperature of the air supplied to the room rises due to the sensible heat load in the room, and is controlled to a set temperature of 26 ° C. At this time, the cold water rises to 12 ° C. to 17 ° C. in the return pipe 13, and is cooled again to 7 ° C. by a water-type central air conditioning system (not shown) and flows to the outgoing pipe 12.

  The controller 21 (heat quantity calculating means 21b) detects the temperature T11 of the outgoing pipe temperature sensor 26, the temperature T12 of the return pipe temperature sensor 27, and the flow rate M of the flowmeter 33 (FIGS. 4P4, P5, P6), and ( 1) Calculate the heat of treatment according to the equation (P7 in FIG. 4).

  Then, the controller 21 (heat quantity calculation means 21b) determines whether or not the heat quantity Q has become 1/2 or less of the maximum heat quantity that can be processed by the air conditioner 3 (P8 in FIG. 4). When the heat quantity Q is greater than 1/2 of the maximum heat quantity that can be processed (air conditioning load factor 50%), the controller 21 (heat quantity calculation means 21b) returns to step P1, and the room temperature setting means 21a controls the control valve. By controlling both 36 and 37, the heat exchange by the two heat exchangers 6 and 7 is performed and the operation of maintaining the room temperature at the set value is continued (FIGS. 4P1 to P3). That is, from the air conditioning load factor 100% to 50% (region (c) in FIG. 2), the heat exchange operation is performed using the two heat exchangers 6 and 7 in this way. When the air-conditioning load factor is 80%, the flow rate ratio of the heat exchangers 6 and 7 is about 90% (see the thick solid line in FIG. 2), and the same characteristics as the conventional one using the single heat exchanger 56 (see the broken line in FIG. 2). )

  Next, when the heat quantity becomes ½ of the maximum heat quantity to be processed (air-conditioning load factor is 50%) at night in the summer or in the middle and winter seasons ((b) in FIG. 2), the following operation is performed. . That is, when the controller 21 (heat quantity calculation means 21b) detects that the heat quantity is ½ of the maximum heat quantity that can be processed (the air conditioning load factor is 50%) by the calculation of the equation (1), the controller 21 (Control valve closing means 21c) fully closes the control valve 37, sets the flow rate of the corresponding heat exchanger 7 to 0 (see (d) to (e) in FIG. 2, FIG. 6P1), and controls the controller 21 (Flow control means 21b) opens the control valve 36 to increase the flow rate so that the flow rate ratio of the heat exchanger 6 is 35% to 50% (see (d) to (f) in FIG. 2), The maximum capacity operation state of the heat exchanger 6 is set (FIG. 6P2).

  When the control is performed not by the amount of heat but by the temperature difference, the following control is performed (FIG. 5). Note that steps P11 and P12 in FIG. 5 are the same control as steps P1 and P2. The controller 21 (temperature difference calculation means 21b) detects the temperature t1 of the mixed air temperature sensor 23 of the indoor air and the outside air and the temperature t2 of the supply air temperature sensor 24 (FIG. 5P14, P15), and from the above equation (2) The temperature difference is calculated (P16 in FIG. 5).

  Then, the controller 21 (temperature difference calculation means 21b) determines whether or not the thermal temperature difference Δt is equal to or less than 1/2 (for example, 7.5 ° C.) of the maximum processable temperature difference (for example, 15 ° C.) of the air conditioner 3. Is determined (FIG. 5P17). If the temperature difference Δt is larger than half of the maximum processable temperature difference, the controller 21 (temperature difference calculating means 21b) returns to step P11, and the indoor temperature setting means 21a controls the control valves 36 and 37. By controlling both, heat exchange is performed by the two heat exchangers 6 and 7, and the operation of maintaining the room temperature at the set value is continued (P11 to P13 in FIG. 5). That is, from the air conditioning load factor 100% to 50% (region (c) in FIG. 2), the heat exchange operation is performed using the two heat exchangers 6 and 7 in this way. When the air-conditioning load factor is 80%, the flow rate ratio of the heat exchangers 6 and 7 is about 90% (see the thick solid line in FIG. 2), and the same characteristics as the conventional one using the single heat exchanger 56 (see the dotted line in FIG. 2). )

  Next, when the temperature difference becomes 1/2 of the maximum processing temperature difference (15 ° C) (7.5 ° C, air conditioning load factor is equivalent to 50%) at night or in the middle and winter in summer ( The following operations are performed as shown in FIG. That is, when the controller 21 (temperature difference calculation means 21b) detects that the temperature difference is ½ of the maximum processable temperature difference (the air conditioning load factor is 50%) by the calculation of the equation (2), The controller 21 (control valve closing means 21c) fully closes the control valve 37, sets the flow rate of the corresponding heat exchanger 7 to 0 (see (D) to (E) in FIG. 2, FIG. 6P1), The controller 21 (flow rate control means 21d) opens the control valve 36 and increases the flow rate so that the flow rate ratio of the heat exchanger 6 is 35% to 50% (from (D) to (F) in FIG. 2). (See Fig. 6P2).

  In either case of the heat amount control or temperature difference control, after the flow rate of the heat exchanger 7 is set to 0, the following control is performed.

  When the operation of the heat exchanger 7 is stopped, the operation is switched to the maximum capacity operation (a state where the maximum flow rate ratio is 50%) of only the heat exchanger 6 (see (a) to (f) in FIG. 2). In the range of the load factor of 50% or less of the air conditioning load factor (region (G) in FIG. 2), the air conditioner 3 is operated with only the heat exchanger 6 operating as described above.

  At this time, the indoor air (return air RA) and the outside air (OA) after heat exchange input to the air conditioner 3 are transferred to the heat exchanger 7 in which the circulation of cold water (or hot water) is stopped by the control valve 37. It becomes air that has not been heat-exchanged, and air that has been heat-exchanged in the heat exchanger 6 in which cold water (or hot water) is circulated, and the two airs are mixed by the blower fan 31 and supplied to the room, In this state, the controller 21 (room temperature setting means 21a) is configured to control the control valve of the heat exchanger 6 in which cold water (or hot water) is circulated so that the room temperature or the supply air temperature becomes the set temperature. The flow rate of cold water (or hot water) is increased or decreased by 36. That is, about half of the total amount of the return air 46 and the outside air 47 passes through the heat exchanger 6 that is operating, and about half of the total amount passes through the heat exchanger 7 that is stopped.

  For example, assuming that the temperature of the air-fuel mixture 46, 47 of indoor air (return air RA: 26 ° C.) and outside air OA (28 ° C.) after heat exchange is 27 ° C., the room temperature is controlled to 26 ° C. The control valve 36 is controlled so that the air that has passed through the heat exchanger 6 drops to, for example, 15 ° C., and the air that has passed through the stopped heat exchanger 7 remains at 27 ° C. without heat exchange. And air at 15 ° C. and air at 27 ° C. are mixed by the blower 31, and as a result, the air is supplied to the room as air at about 21 ° C.

  In the region (G) where the air conditioning load factor is 50% or less, the controller 21 (indoor temperature setting means 21a) similarly sets the temperature of the indoor temperature sensor 25 or the supply air temperature sensor 24 to the set temperature (for example, indoors). Whether the temperature is 26 ° C. or the supply air temperature 21 ° C.) (P3 and P4 in FIG. 6) and the supply air temperature or the room temperature is higher than the set temperature, or the supply air temperature or the room temperature is the set temperature. If it is lower, only the control valve 36 is controlled to open and close to control the flow rate of the heat exchanger 6 (FIG. 6P5), and control is performed so that the room temperature and the supply air temperature maintain the set temperatures ((( G) area).

  Here, when the flow rate ratio of 50% or less of the air-conditioning load factor (thick solid line in FIG. 2) is compared with the characteristic of one conventional heat exchanger 56 (broken line in FIG. 2), the overall flow rate ratio is reduced by about 20%. Thus, it can be seen that operation with a smaller flow rate is possible in the region (g) where the air conditioning load factor is 50% or less. For example, the flow rate ratio at an air conditioning load factor of 30% requires a flow rate ratio of 60% in the case of one heat exchanger 56, but in the present invention, it can be seen that operation is possible at a flow rate ratio of 40%. . Therefore, it is possible to sufficiently exchange heat with a small flow rate in the heat exchanger (heat exchanger 6 in the case of the present embodiment) to exchange heat, and as a result, a sufficient temperature difference between the outgoing pipe 12 and the return pipe 13 is secured. become able to. As a result, it is possible to realize a reduction in pump power for circulating cold water (or hot water) to the outgoing pipe 12 and the return pipe 13, thereby improving the efficiency of the heat source unit and the performance count COP, and in the two-pump system, Significant reduction of bypass flow rate is possible.

  Further, in the region where the air-conditioning load factor is 50% or less as described above ((G) in FIG. 2), for example, if the condensation temperature of air is 18 ° C. or less, the air temperature in the heat exchanger 6 is as described above. When the temperature is decreased to 15 ° C., dew condensation occurs in the heat exchanger 6, so that the air that has passed through the heat exchanger 6 can be dehumidified. In an intermediate period where the air conditioning load factor is 50% or less, if the room temperature is set to 26 ° C. in one conventional heat exchanger 56, the air is lowered to 21 ° C. in the heat exchanger 56. In this case, the air temperature cannot be lowered to the dew condensation temperature, and it becomes difficult to dehumidify the air passing through the heat exchanger 56. Thus, in addition to the above-described effect of reducing the flow rate, the present invention can also exhibit an effect that the dehumidifying ability is high in an intermediate period or the like.

  The above explanation has been made mainly on the case where the heat exchanger is divided into two stages. For example, the air-conditioning load factor-flow rate characteristic when the heat exchanger is divided into three stages is schematically shown by a thick broken line in FIG. . In this case, in the area (li), the three heat exchangers are operated and the corresponding three control valves are controlled to keep the room temperature constant, and the conventional one heat exchanger is used. The control is equivalent to that of the case. The maximum flow rate ratio of each heat exchanger is 33% (FIG. 7b ', point c'), and the total of the three stages of heat exchangers is 100% (FIG. 7a 'point).

  When the processing heat quantity Q decreases by an amount corresponding to 1/3 of the maximum heat quantity that can be processed (air conditioning load factor 100%) ((N) in FIG. 7), one of the three control valves is fully closed and fully closed. The control valve is not opened and the flow rate is increased to obtain the maximum flow rate ratio (2/3 of the 100% flow rate ratio) of the remaining two heat exchangers ((l) in FIG. 7). Hereinafter, in the region (e), the opening / closing control of the control valves corresponding to the two heat exchangers in operation is performed to control the room temperature to be constant. In this state, the flow rate ratio is about 10% lower than the flow rate of the general heat exchanger 56 (broken line in FIG. 7), and the operation can be performed with a smaller flow rate.

  Further, when the heat quantity Q decreases by an amount corresponding to 1/3 of the maximum heat quantity that can be processed (air conditioning load factor 100%) ((W) in FIG. 7), one of the two control valves in operation is fully closed. Then, the control valve that is not fully closed is opened to increase the flow rate, and the maximum flow rate ratio of one heat exchanger (1/3 of the 100% flow rate ratio) is obtained ((f) in FIG. 7). And in area | region (Y), the opening / closing control of the control valve corresponding to one heat exchanger in operation is performed, and room temperature is controlled uniformly. In this region (Y), even when compared with the case of a two-stage heat exchanger (thick solid line in FIG. 7), operation can be performed with a smaller flow rate, and the minimum flow rate ratio can be reduced to 15%. More efficient operation is possible.

  In this way, by performing the same control by increasing the number of stages in the heat exchanger, the flow rate ratio of the heat exchanger and the change characteristics of the air conditioning load factor are the most efficient ideal flow ratio characteristics indicated by the thin solid line You can get closer to.

  As described above, the heat exchanger is divided into n stages, and a control valve is installed in each return pipe or outgoing pipe for each divided heat exchanger, and a heat exchanger is provided for each heat exchanger by these control valves. It is configured so that the amount of passing cold water (or hot water) can be increased, decreased, or stopped, and the indoor temperature or supply air temperature is detected so that the indoor temperature or supply air temperature becomes the set temperature, and cold water (or hot water) is detected. Open and close the control valves of the circulating heat exchanger to increase / decrease the chilled water (or hot water) passing through each heat exchanger to control the room temperature to a constant level. The temperature difference is detected from the mixed air temperature and the supply air temperature, and each time the temperature difference becomes a set value determined by the number of divisions for all loads (for example, the processing temperature difference is 1 / n of the maximum temperature difference that can be processed). Every time it falls to the above), or the return temperature, return temperature and flow meter to the heat exchanger Whenever the amount of heat reaches a set value determined by the number of divisions for all loads (for example, every time the amount of processed heat decreases by 1 / n of the maximum amount of heat that can be processed), the control valve Either one is fully closed and the flow rate of the other control valve is increased to reduce the flow rate corresponding to 1 / n with respect to the total flow rate at full load. After the valve is fully closed, the control valve corresponding to the operating heat exchanger is controlled to open and close to control the room temperature to be constant.

  In place of the heat exchange heat amount, a control valve for increasing or decreasing the flow rate is installed at the position of the flow meter 33, and the control valves 36 and 37 can be controlled to be ON / OFF controlled according to the valve opening degree of the control valve. .

  As described above in detail, according to the multistage heat exchanger divided into two or more of the air conditioners and the control method according to the present invention, the indoor temperature or the supply air temperature is detected and passed through the heat exchanger. While the amount of cold water (or hot water) is controlled to increase / decrease, processing temperature difference is detected by detecting the mixed air temperature and supply air temperature of indoor air and outside air, or processing heat amount by detecting the return temperature, return temperature and flow rate Heat exchange to exchange heat by dividing the heat exchanger that exchanges heat with air and the heat exchanger that does not exchange heat by fully closing any of the control valves installed for each heat exchanger. The vessel can sufficiently exchange heat, and as a result, a sufficient temperature difference between the outgoing pipe and the return pipe can be secured. As a result, the pump power can be reduced, the efficiency of the heat source unit can be improved, and the coefficient of performance COP can be improved. In the two-pump system, the bypass flow rate can be greatly reduced.

  Furthermore, in the two-pump system in which the cold water primary pump and the cold water secondary pump are installed, the flow rate in the bypass pipe can be greatly reduced.

  In the above-described embodiment, as a reference for detecting that the air conditioning load factor of the air conditioner has reached 50% in the intermediate period or the like, the embodiment by the calculation of the heat amount and the embodiment by the calculation of the temperature difference are shown. It may be selected according to the installation status of the air conditioner. For example, it is preferable to perform control based on the amount of heat when only a machine is operating and no one is present in a factory or the like, and when there is a person and it is important to introduce not only return air but also outside air, it is preferable to perform control based on a temperature difference. .

  According to the air conditioner control method and the air conditioner according to the present invention, an efficient air conditioner control method and an air conditioner are realized in the water-type central heat source system, so that buildings, hotels, research facilities, factories, etc. It can be widely used as an air conditioning system.

It is a block diagram showing the outline of the air conditioner which uses the control method of the air conditioner which concerns on this invention. It is operation | movement explanatory drawing which represented the control method which concerns on this invention with the flow rate ratio of the air-conditioning load factor and the heat exchanger. It is a functional block diagram of the controller of the air conditioner concerning the present invention. It is a flowchart which shows the operation | movement procedure of the controller of an air conditioner same as the above. It is a flowchart which shows the operation | movement procedure of the controller of an air conditioner same as the above. It is a flowchart which shows the operation | movement procedure of the controller of an air conditioner same as the above. It is operation | movement explanatory drawing which represented the control method which concerns on this invention with the flow rate ratio of the air-conditioning load factor and the heat exchanger. It is a block diagram showing the outline of the conventional air conditioner.

Explanation of symbols

3 Air Conditioner 6 Heat Exchanger 7 Heat Exchanger 12 Outward Pipe 13 Return Pipe 21 Controller 21a Room Temperature Setting Means 21b Calorific Value Calculation Means (Temperature Difference Calculation Means)
21c Control valve closing means 21d Flow rate control means 23 Mixed air temperature sensor 24 Supply air temperature sensor 25 Indoor temperature sensor 26 Outgoing pipe temperature sensor 27 Return pipe temperature sensor 33 Flow meter 36 Control valve 37 Control valve

Claims (8)

Dividing the heat exchanger in the air conditioner into two parts, circulating and supplying cold water (or hot water) to the two divided heat exchangers, and passing the mixed air of indoor air and outside air through these heat exchangers A method of controlling an air conditioner that exchanges heat by
A control valve is installed in each return pipe or outgoing pipe of the divided heat exchanger, and the amount of cold water (or hot water) passing through the heat exchanger for each heat exchanger is increased or decreased by these control valves. Configured to be able to stop all,
Each heat exchange is performed by detecting the room temperature or the supply air temperature so that the room temperature or the supply air temperature becomes the set temperature, and opening and closing each control valve of the heat exchanger in which the cold water (or hot water) is circulated. Increase or decrease control of cold water (or hot water) passing through the vessel to control the room temperature or the supply air temperature to be constant,
Furthermore, the amount of heat is detected based on the temperature of the cold water (or hot water) sent to each heat exchanger, the return temperature, and the flow rate passing through each heat exchanger, and the amount of heat is determined by the number of divisions for all loads. When it becomes a value, while fully closing any one of the control valves installed in the divided heat exchanger,
By controlling the flow rate of the other control valves to be lower than the total flow rate of the two heat exchangers, control is performed to ensure a temperature difference between the forward temperature and the return temperature,
On the other hand, after fully closing any one of the control valves, the indoor air and the outside air after heat exchange input to the air conditioner are exchanged in a heat exchanger in which the circulation of cold water (or hot water) is stopped by the control valve. It becomes air that has not been heat-exchanged, and air that has been heat-exchanged in a heat exchanger in which cold water (or hot water) is circulated, and the two airs are mixed and supplied to the room. An air conditioner characterized in that cold water (or hot water) is controlled to increase or decrease by the control valve of the heat exchanger in which cold water (or hot water) is circulated so that the temperature or the supply air temperature becomes a set temperature. Control method. In the control method of the air conditioner according to claim 1,
Detects the amount of heat based on the cold water (or hot water) temperature and return temperature to each heat exchanger, and the flow rate passing through each heat exchanger. In this case, instead of the control of fully closing any one of the control valves installed in the divided heat exchanger,
By detecting the mixed air temperature and the supply air temperature of the indoor air and the outside air, the temperature difference between them is measured, and when the temperature difference becomes a set value determined by the number of divisions for all loads, it is divided. A control method for an air conditioner, wherein control is performed to fully close any one of the control valves installed in the heat exchanger. The heat exchanger in the air conditioner is divided into two or more n stages (n is an integer of 2 or more), and cold water (or hot water) is recirculated and supplied to the divided n stage heat exchangers. A control method for an air conditioner that exchanges heat by allowing room air and outside air to pass through the chamber,
The heat exchanger is divided into n stages, and control valves are respectively installed in the return pipe or the outgoing pipe for each divided heat exchanger, and cold water (or passed through the heat exchanger for each heat exchanger by these control valves (or Configured to increase or decrease the amount of hot water)
Each heat exchange is performed by detecting the room temperature or the supply air temperature so that the room temperature or the supply air temperature becomes the set temperature, and opening and closing each control valve of the heat exchanger in which the cold water (or hot water) is circulated. Increase or decrease the control of cold water (or hot water) passing through the vessel to control the room temperature to a constant level,
Further, when the amount of heat is detected from the temperature going back to the heat exchanger, the return temperature and the flow meter, and the amount of heat reaches a set value determined by the number of divisions for all loads, one of the control valves is selected. Is fully closed,
By increasing the flow rate of the other control valves and reducing the flow rate corresponding to 1 / n with respect to the total flow rate at full load, a temperature difference between the going temperature and the return temperature is secured. Control to
On the other hand, after any control valve is fully closed, the indoor air and the outside air after heat exchange input to the air conditioner are cooled in a heat exchanger in which the circulation of cold water (or hot water) is stopped by the control valve. It becomes air that has not been heat-exchanged, and air that has been heat-exchanged in a heat exchanger in which cold water (or hot water) is circulated, and these air are mixed and supplied to the room. An air conditioner characterized in that cold water (or hot water) is controlled to increase or decrease by the control valve of the heat exchanger in which cold water (or hot water) is circulated so that the temperature or the supply air temperature becomes a set temperature. Control method. In the control method of the air conditioner according to claim 3,
When the amount of heat is detected from the temperature going back to the heat exchanger, the return temperature and the flow meter, and when the amount of heat reaches the set value determined by the number of divisions for the full load, any one of the control valves is Instead of a fully closed control,
The temperature difference is measured by detecting the mixed air temperature and the supply air temperature of the indoor air and the outside air, and each time the temperature difference becomes a set value determined by the number of divisions for the full load, the control valve A control method for an air conditioner, characterized by performing control to fully close any one of them. The heat exchanger in the air conditioner is divided into two or more n stages (n is an integer of 2 or more), and a control valve is installed in each return pipe or outgoing pipe of each divided heat exchanger. While circulating and supplying cold water (or hot water) to the heat exchanger, the indoor air and the outside air are passed through the heat exchanger, so that the cold water (or hot water) and the air are configured to exchange heat.
A forward pipe temperature sensor is installed in the common forward pipe of each heat exchanger, a return pipe temperature sensor and a flow meter are installed in the common return pipe of each of the heat exchangers, and the supply air is supplied to the air supply target room. Air temperature sensor or indoor temperature sensor is provided,
In addition, a controller is provided that can recognize the detected temperature of the supply air temperature sensor or indoor temperature sensor, the detected temperature of the outgoing pipe temperature sensor and the return pipe temperature sensor, the detected flow rate of the flowmeter, and control the opening and closing of the control valves. ,
The controller recognizes the detected temperature of the supply air temperature sensor or the indoor temperature sensor, and indoor temperature setting means for controlling the opening and closing of the control valve so that the detected temperature becomes a set value;
A calorific value calculating means for calculating a calorific value based on the detected temperature of the outgoing pipe temperature sensor, the detected temperature of the return pipe temperature sensor, and the detected flow rate;
Every time it detects that the heat quantity of the heat quantity calculation means has become 1 / n or less of the full load, any one of the control valves in operation is fully closed, and the cold water ( Or a control valve closing means for stopping the circulation of hot water),
A flow rate control means for controlling opening and closing of the operating control valve so that the flow rate of the heat exchanger in operation is reduced by 1 / n with respect to the flow rate at the time of full load together with the full closing of any one control valve; The air conditioner characterized by comprising. The heat exchanger in the air conditioner is divided into two or more n stages (n is an integer of 2 or more), and a control valve is installed in each return pipe or outgoing pipe of each divided heat exchanger. While circulating and supplying cold water (or hot water) to the heat exchanger, the indoor air and the outside air are passed through the heat exchanger, so that the cold water (or hot water) and the air are configured to exchange heat.
In addition to providing a mixed air temperature sensor of indoor air and outside air on the inlet side of the heat exchanger, a supply air temperature sensor or an indoor temperature sensor is provided in a room to be supplied,
Furthermore, a controller capable of recognizing the detected temperature of the mixed air temperature sensor, the supply air temperature sensor or the indoor temperature sensor and controlling the opening and closing of the control valves is provided.
The controller recognizes the detected temperature of the supply air temperature sensor or the indoor temperature sensor, and indoor temperature setting means for controlling the opening and closing of the control valve so that the detected temperature becomes a set value;
A temperature difference calculating means for calculating a temperature difference between the detected temperatures of both the sensors based on the detected temperature of the mixed air temperature sensor and the supply air temperature sensor;
Whenever the temperature difference of the temperature difference calculating means detects that the temperature difference has decreased by 1 / n with respect to the temperature difference at full load, one of the operating control valves is fully closed. A control valve closing means for stopping circulation of cold water (or hot water) in the heat exchanger;
A flow rate control means for controlling opening and closing of the operating control valve so that the flow rate of the heat exchanger in operation is reduced by 1 / n with respect to the flow rate at the time of full load together with the full closing of any one control valve; The air conditioner characterized by comprising.   The indoor temperature setting means is characterized in that after closing any one of the control valves, the control valve corresponding to the heat exchanger in operation is controlled to open and close to maintain the room temperature constant. Item 6. The air conditioner according to item 6 or 7. Cooling water flowing through the heat exchanger by controlling the opening and closing of the control valve of the heat exchanger using an air conditioner whose change characteristic of the flow ratio of the heat exchanger and the air conditioning load factor approximates a linear function ( Or a control method of an air conditioner that controls the supply air temperature or the room temperature to become a set temperature by increasing or decreasing the flow rate of hot water),
The heat exchanger is configured in multiple stages, and is configured so that the flow rate at the full load of the cold water (or hot water) of the heat exchanger at the full load can be secured by operating all the heat exchangers,
While stopping the cold water (or hot water) flowing in any one of the multi-stage heat exchangers as the air conditioning load decreases, the operation of the heat exchangers is stopped.
Control the control valve so that the flow rate of the heat exchangers in operation other than the stopped heat exchanger is in the state of the maximum flow rate ratio of those heat exchangers,
After stopping any of the above heat exchangers, the air conditioner control is characterized in that the supply air temperature or the room temperature is controlled to become the set temperature by increasing or decreasing the flow rate of the operating heat exchanger. Method.

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