WO2008088137A2

WO2008088137A2 - Air conditioning system and control method thereof

Info

Publication number: WO2008088137A2
Application number: PCT/KR2007/006869
Authority: WO
Inventors: Dong Jun Yang; Dong Keun Yang; Gi Seop Lee
Original assignee: Lg Electronics Inc.
Priority date: 2007-01-19
Filing date: 2007-12-27
Publication date: 2008-07-24
Also published as: KR100860035B1; WO2008088137A3

Abstract

The present invention discloses an air conditioning system comprising at least one outdoor unit, at least one air handling unit connected with the outdoor unit to cool/heat or ventilate a room, and a control device to recognize an identification number of the air handling unit and give a new address to the air handling unit through communication with the air handling unit.

Description

AIR CONDITIONING SYSTEM AND CONTROL METHOD

THEREOF

Technical Field

[1] The present invention relates to an air conditioning system and a control method thereof, and more particularly, to an air conditioning system and a control method thereof capable of efficiently operating the system. Background Art

[2] In general, an air handling unit (AHU) is a device used to condition air in a room by supplying outdoor air into a room and exhausting or circulating room air. The AHU heats or cools air by use of a cooling source or a heating source, and blows hot or cold air to a space to be air-conditioned through a duct.

[3] As the cooling source and heating source, a combined cold water coil and hot water coil may be used. In a cooling mode, cold water is fed to the coil from a cooler. In a heating mode, steam or hot water is fed to the coil from a boiler. Recently, it is a trend that a heat exchanger forming a refrigeration cycle is used.

[4] In addition, the AHU further has functions of filtration to purify air and humidi- fication and dehumidification according to a room condition, thereby making the room comfortable. In other words, the AHU is constituted so as to purify, cool, dehumidify, heat and humidify air supplied to a room. The air conditioned adequately for a room environment by the AHU is blown to each room by a fan.

[5] The air used in the air conditioning returns to the AHU, and is partially mixed with outdoor air for ventilation, and then is cooled or heated again. Disclosure of Invention Technical Problem

[6] However, the above conventional air conditioning system has the following problems.

[7] First, the conventional air conditioning system keeps the total spaces to be air- conditioned in a cooling condition or in a heating condition. Thus, the conventional air conditioning system cannot cool/heat or ventilate the respective rooms, correspondingly to cooling/heating load of the rooms.

[8] Second, the conventional air conditioning system totally carries out communication between plural indoor units and plural outdoor units. Thus, because the communication between the indoor units and the outdoor units cannot be achieved independently, the conventional air conditioning system cannot operate the indoor units corresponding to cooling/heating load of the respective rooms. Technical Solution

[9] Accordingly, the present invention is directed to an air conditioning system and a control method thereof that substantially obviate one or more problems due to limitations and disadvantages of the related art.

[10] An object of the present invention is to provide an air conditioning system capable of controlling indoor units or air handling units corresponding to required cooling/heating load of respective separate rooms.

[11] Another object of the present invention is to provide an air conditioning system capable of efficiently carrying out communication among outdoor units, indoor units and air handling units, and a control method of the air conditioning system.

[12] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

[13] To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, an air conditioning system comprises: at least one outdoor unit; at least one air handling unit connected with the outdoor unit to cool/heat or ventilate a room; and a control device to recognize an identification number of the air handling unit and give a new address to the air handling unit through communication with the air handling unit.

[14] The air conditioning system may further comprise at least one indoor unit connected with the outdoor unit to cool/heat the room selectively or simultaneously with the air handling unit.

[15] The air conditioning system may further comprise a load sensor to sense cooling/ heating load of the room to control the air handling unit and the indoor unit according to the cooling/heating load of the room.

[16] The air conditioning system may further comprise a refrigerant distribution device to control refrigerant flowing through the outdoor unit, the air handling unit and the indoor unit. The refrigerant distribution device may be controlled by the control device.

[17] The control device may selectively or simultaneously control the air handling unit according to the new address of the air handling unit.

[18] The control device may recognize an identification number of the indoor unit and may give a new address to the indoor unit to control the air handling unit and the indoor unit. [19] The air handling unit may include plural divided heat exchangers which are respectively given with identification numbers so as to be operated individually by the control device according to cooling/heating load of the room. [20] The at least one outdoor unit may include plural outdoor units, and the plural outdoor units may be operated alternately corresponding to the plural divided heat exchangers. [21] A part of the plural divided heat exchangers may be controlled to be used for cooling operation, and the remaining part of the plural divided heat exchangers may be controlled to be used for heating operation. [22] The outdoor unit may have a variable capacity in accordance with capacities of the divided heat exchangers. [23] In another aspect of the present invention, there is provided a control method of an air conditioning system, comprising: recognizing an identification number with respect to at least one air handling unit connected with at least one outdoor unit for cooling/ heating or ventilating a room; and setting a new address with respect to the recognized identification number of the air handling unit. [24] The method may further comprise operating selectively or simultaneously the air handling unit in accordance with the new address of the air handling unit. [25] The method may further comprise controlling at least one indoor unit connected with the outdoor unit independently from the air handling unit. [26] The method may further comprise controlling refrigerant flowing through the outdoor unit, the air handling unit and the indoor unit which are operated according to a command from a control device. [27] The step of controlling the indoor unit may include recognizing an identification number with respect to the indoor unit, and setting a new address with respect to the identification number of the indoor unit. [28] The method may further comprise sensing cooling/heating load of the room to control simultaneously or selectively the air handling unit and the indoor unit. [29] The step of operating the air handling unit may include operating individually plural divided heat exchangers provided in the air handling unit in accordance with cooling/ heating load of the room. [30] The at least one outdoor unit may include plural outdoor units. At the step of operating the plural divided heat exchangers, the plural outdoor units may be operated alternately corresponding to the plural divided heat exchangers. [31] At the step of operating the plural divided heat exchangers, a part of the plural divided heat exchangers may be operated in a cooling mode, and the remaining part of the plural divided heat exchangers may be operated in a heating mode. [32] At the step of operating the plural divided heat exchangers, the outdoor unit may have a variable capacity in accordance with capacities of the divided heat exchangers. Advantageous Effects

[33] The air conditioning system and the control method thereof according to the present invention have the following effects.

[34] First, since the air handling units can be selectively or simultaneously controlled corresponding to the respective rooms through the communication of the air handling units installed in the respective rooms and the outdoor units, operating efficiency can be increased. In other words, by supplying as much energy as required for the room intended to be air conditioned, the operating efficiency can be increased.

[35] Second, by recognizing the ID numbers with respect to the indoor units and the air handling units connected with the outdoor units and giving the new addresses to them, the indoor units and the air handling units can be operated individually based on the addresses, thereby effectively and smoothly controlling the system.

[36] Third, the refrigerant can be easily distributed by installing the refrigerant distribution device to control the refrigerant flowing through the outdoor units, the air handling units and the indoor units.

[37] Fourth, since the plural divided heat exchangers are installed in one air handling unit, in a case where the cooling/heating load is small, the divided heat exchangers are used in part, and as a result the system can be effectively operated. Brief Description of the Drawings

[38] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:

[39] FIG. 1 is a constitutional view schematically showing a constitution of an air conditioning system according to an exemplary embodiment of the present invention;

[40] FIG. 2 is a piping diagram when the air conditioning system according to the present invention is operated in a main heating mode;

[41] FIG. 3 is a piping diagram when the air conditioning system according to the present invention is operated in a main cooling mode;

[42] FIG. 4 is a block diagram showing a constitution for controlling the air conditioning system according to the present invention;

[43] FIG. 5 is a flow chart of a control method of the air conditioning system according to the present invention; and

[44] FIG. 6 is a constitutional view schematically showing a constitution of an air conditioning system according to another exemplary embodiment of the present invention. Mode for the Invention

[45] Reference will now be made in detail to the preferred embodiments of the present invention associated with an air conditioning system and a control method thereof, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[46] An air conditioning system according to an exemplary embodiment of the present invention will be described with reference to FIG. 1.

[47] An air conditioning system includes at least one outdoor unit 100, at least one air handling unit 300 connected to the outdoor unit 100 to cool/heat or ventilate a room, and a control device which recognizes an identification (ID) number of each air handling unit 300 and provides a new address to each air handling unit 300 through communication with the air handling unit 300, and selectively or simultaneously controls the air handling unit 300 according to the address.

[48] The air conditioning system further includes at least one indoor unit 200 which is connected with the outdoor unit 100 and is controlled separately from the air handling unit 300. The control device controls the flow of refrigerant, as well as carries out communication among the outdoor unit 100, the indoor unit 200 and the air handling unit 300.

[49] The indoor unit 200 and the air handling unit 300 may be installed in the same room, or may be installed individually in the respective sectioned rooms. Hereinafter, the present invention will be explained with reference to the constitution such that the indoor unit 200 and the air handling unit 300 are installed individually in the respective rooms.

[50] The air conditioning system further includes a refrigerant distribution device 400 to regulate an amount of the refrigerant flowing through the air handling unit 300, the indoor unit 200 and the outdoor unit 100. More particularly, a first end of the refrigerant distribution device 400 is connected with the outdoor unit 100, and a second end of the refrigerant distribution device 400 is connected with the indoor unit 200 or the air handling unit 300. The detailed constitution of the indoor unit, the outdoor unit and the refrigerant distribution device will be explained later with reference to FIGs. 2 and 3.

[51] The air handling unit 300 includes a first blower fan 310 to exhaust room air (R. A.) to the outside, a second blower fan 320 to supply air introduced from the outside to the room, and an air handling unit heat exchanger 330 to heat or cool the air supplied to the room.

[52] The air handling unit 300 may further include a filtration device 327 to purify the supplied air (S. A.) to be supplied to the room, and a humidity adjusting device 329 to humidify or dehumidify the air.

[53] The air handling unit 300 is provided with an outdoor air suction port 323 to suck the outdoor air (O. A.) into the air handling unit 300, a room air suction port 311 to suck the room air (R. A.) into the air handling unit 300, an exhaust port 313 to exhaust the room air to the outdoor, and an air blowing port 321 to supply the air to the room.

[54] The outdoor air suction port 323, the room air suction port 311, the exhaust port 313 and the air blowing port 321 are respectively connected with ducts (not shown) forming passages through which the air flows, and the ducts communicate with the room or the outdoor. Accordingly, the air is sucked from the outdoor or the room, and is exhausted to the outdoor or the room. The air handling unit heat exchanger 330 forming a refrigeration cycle is mounted inside the air handling unit 300. The air handling unit heat exchanger 330 is connected with the outdoor unit 100, and heat exchanges the supplied air (S. A.) to be supplied to the room and exhausts the supplied air.

[55] When the air handling unit 300 is operated in a heating mode, the exhausted air

(E.A.) is exhausted at a temperature higher than the outdoor air (O.A.). At this time, the air handling unit 300 may be constituted so that the exhausted air (E.A.) exhausted to the outdoor and the outdoor air (O.A.) introduced from the outdoor can be heat exchanged with each other. To this end, a heat transfer element may be mounted between an exhaust port housing 315 formed with the exhaust port 313 and a suction port housing 325 formed with the outdoor air suction port 323.

[56] More particularly, the heat transfer element includes an exhaust passage which connects an outlet of the first blower fan and the exhaust port, and a suction passage which connects the outdoor air suction port and an inlet of the second blower fan. The exhaust passage and the suction passage are arranged to be crossed alternately in a thin layer form. As a result, the exhausted air (E.A.) flowing through the exhaust passage and the outdoor air (O.A.) flowing through the suction passage are heat exchanged with each other.

[57] There are provided extension pipes which extend from the exhaust port and the outdoor air suction port, and a total heat exchanger may be additionally provided in the extension pipes to heat exchange the exhausted air and the outdoor air.

[58] The air conditioning system further includes a load sensor (not shown) which senses cooling/heating load of the room to control the air handling unit 300 and the indoor unit 200 according to the cooling/heating load of the room. In this embodiment, a temperature sensor is used as the load sensor. However, the load sensor is not limited to the temperature sensor.

[59] For example, the load sensor may be configured as a contamination sensor which measures contamination of the room.

[60] The load sensor is mounted in a portion of the room, and data of the load sensor is transmitted to the control device. In response to the data, the control device air conditions the room.

[61] FIG. 2 is a view showing a state in which the air conditioning system is operated in a main heating mode with respect to one air handling unit and two indoor units, and FIG. 3 is a view showing a state in which the air conditioning system is operated in a main cooling mode.

[62] Referring to FIGs. 1 to 3, the outdoor unit 100 includes plural compressors 110 to compress the refrigerant, plural outdoor heat exchangers 120 to heat exchange the refrigerant, a 4- way valve 130 disposed at outlet sides of the compressors 110 to switch the passage of the refrigerant, and an accumulator 140 connected to suction inlet sides of the compressors 110 to supply gas refrigerant to the compressors 110.

[63] The 4- way valve 130 switches the flow direction of the refrigerant depending on whether the room is intended to be heated or cooled. For example, in a case where the air conditioning system is operated to mainly heat the room, i.e., is in the main heating operation mode, the 4- way valve 130 guides the refrigerant discharged from the compressors 110 to directly flow to the refrigerant distribution device 400 without passing through the outdoor heat exchangers 120.

[64] When the air conditioning system is operated in the main heating mode, the outdoor heat exchangers 120 serve as evaporators, and the refrigerant evaporated in the outdoor heat exchangers 120 is sucked into the compressors 110 and is compressed. An evaporation fan 150 is provided near the outdoor heat exchangers 120 to assist the evaporation of the refrigerant when the outdoor heat exchangers 120 serve as evaporators.

[65] When the air conditioning system is operated to mainly cool the room, i.e., is in the main cooling operation mode, the 4- way valve 130 guides the refrigerant discharged from the compressors 110 to flow to the outdoor heat exchangers 120.

[66] When the air conditioning system is operated in the main cooling mode, the outdoor heat exchangers 120 serve as condensers, and the refrigerant discharged from the compressors 110 is condensed in the outdoor heat exchangers 120. As described above, the passage through which the refrigerant flows is determined by the switching of the 4- way valve 130, and the operation mode of the outdoor unit 100, further the operation mode of the air conditioning system is determined.

[67] An outdoor expansion valve 160 is provided in a pipe which is located at a side of the outdoor heat exchangers 120 opposite to the compressors 110. An electronic expansion valve may be used as the outdoor expansion valve 160. The electronic expansion valve is a valve which adjusts a refrigerant flow rate of an evaporator by use of an electronic control unit. Since the electronic expansion valve has an effect of energy saving, especially when it is used in the system in which the operation time is long and the load variation is large, the electronic expansion valve is being widely used recently.

[68] The air conditioning system further includes at least one indoor unit 200 which is connected with the outdoor unit 100. The indoor unit 200 includes indoor heat exchangers 211 and 221, and indoor expansion valves 213 and 223 which are connected with the indoor heat exchangers 211 and 221 through refrigerant pipes. It is preferable to use an electronic expansion valve as the indoor expansion valves 213 and 223.

[69] The refrigerant distribution device 400 includes refrigerant pipes which connect the outdoor unit 100, the indoor unit 200 and the air handling unit 300, and refrigerant control valves which are mounted in the refrigerant pipes to control the opening and closing of the refrigerant pipes.

[70] Hereinafter, the refrigerant distribution device will be explained with reference to a case in which one outdoor unit 100, one air handling unit 300 and two indoor units (including a first indoor unit 210 and a second indoor unit 220) are operated.

[71] The air conditioning system of this embodiment includes a first refrigerant pipe 410 which connects the outlets of the compressors 110 of the outdoor unit 100 to the first indoor unit 210, the second indoor unit 220 and the air handling unit 300.

[72] The first refrigerant pipe 410 includes a first refrigerant branch pipe 411 of the first refrigerant pipe to connect the outdoor unit 100 to the air handling unit 300, a second refrigerant branch pipe 413 of the first refrigerant pipe to connect the outdoor unit 100 to the first indoor unit 210, and a third refrigerant branch pipe 415 of the first refrigerant pipe to connect the outdoor unit 100 to the second indoor unit 220.

[73] The air conditioning system further includes a second refrigerant pipe 430 which connects the outdoor heat exchangers 120 and the outdoor expansion valve 160 to the first indoor unit 210, the second indoor unit 220 and the air handling unit 300.

[74] The second refrigerant pipe 430 includes a first refrigerant branch pipe 431 of the second refrigerant pipe to connect the outdoor heat exchangers 120 to the air handling unit 300, a second refrigerant branch pipe 433 of the second refrigerant pipe to connect the outdoor heat exchangers 120 to the first indoor unit 210, and a third refrigerant branch pipe 435 of the second refrigerant pipe to connect the outdoor heat exchangers 120 to the second indoor unit 220.

[75] The air conditioning system further includes a third refrigerant pipe 450 which connects the indoor units 200 and the air handling unit 300 to the accumulator 140.

[76] A first end of the third refrigerant pipe 450 is connected to the inlets of the compressors 110 of the outdoor unit 100 via the accumulator 140. A second end of the third refrigerant pipe 450 includes a first refrigerant branch pipe 451 of the third refrigerant pipe connected to the air handling unit 300, a second refrigerant branch pipe 453 of the third refrigerant pipe connected to the first indoor unit 210, and a third refrigerant branch pipe 455 of the third refrigerant pipe connected to the second indoor unit 220.

[77] When the air conditioning system is operated in the main heating mode, the 4-way valve 130 is switched to guide the refrigerant discharged from the compressors 110 to flow to the indoor units 200 and the air handling unit 300 without passing through the outdoor heat exchangers 120.

[78] On the other hand, when the air conditioning system is operated in the main cooling mode, the 4-way valve 130 is switched to guide the refrigerant discharged from the compressors 110 to flow to the indoor units 200 and the air handling unit 300 via the outdoor heat exchangers 120.

[79] If the number of rooms intended to be cooled of the rooms to be air conditioned is larger, the main cooling operation mode is carried out. Conversely, if the number of rooms intended to be heated is larger, the main heating operation mode is carried out.

[80] Whether to operate the outdoor unit 100 in the main heating mode or the main cooling mode can be determined depending on whether the capacities of the units, which are operated in the heating mode, of the indoor units 200 and the air handling unit 300 are larger or the capacities of the units operated in the cooling mode are larger. In other words, whether to be operated in the main heating mode or the main cooling mode can be determined depending on whether heating load is required or cooling load is required.

[81] The refrigerant control valves include first refrigerant control valves 421 and 423 to control the refrigerant flowing to and from the air handling unit 300, second refrigerant control valves 441 and 443 to control the refrigerant flowing to and from the first indoor unit 210, and third refrigerant control valves 461 and 463 to control the refrigerant flowing to and from the second indoor unit 220. An on/off valve may be used as the first refrigerant control valves 421 and 423, the second refrigerant control valves 441 and 443 and the third refrigerant control valves 461 and 463.

[82] The first refrigerant control valves include a first refrigerant control valve 421 of the first refrigerant pipe which is mounted in the first refrigerant branch pipe 411 of the first refrigerant pipe, and a first refrigerant control valve 423 of the third refrigerant pipe which is mounted in the first refrigerant branch pipe 451 of the third refrigerant pipe.

[83] The second refrigerant control valves include a second refrigerant control valve 441 of the first refrigerant pipe which is mounted in the second refrigerant branch pipe 413 of the first refrigerant pipe, and a second refrigerant control valve 443 of the third refrigerant pipe which is mounted in the second refrigerant branch pipe 453 of the third refrigerant pipe.

[84] The third refrigerant control valves include a third refrigerant control valve 461 of the first refrigerant pipe which is mounted in the third refrigerant branch pipe 415 of the first refrigerant pipe, and a third refrigerant control valve 463 of the third refrigerant pipe which is mounted in the third refrigerant branch pipe 455 of the third refrigerant pipe.

[85] Hereinafter, the operation of the air conditioning system according to the present invention as constituted above will be explained in detail.

[86] A user decides whether to heat or cool the respective rooms to be air conditioned, and inputs a command to the system corresponding to the decision. The control device determines the amount of heating load and the amount of cooling load required for the whole system, and compares them.

[87] The control device compares a capacity ratio of the indoor units 200 and the air handling unit 300 to be operated in the cooling mode with a capacity ratio of the indoor units 200 and the air handling unit 300 to be operated in the heating mode. If the heating load is larger, the control device determines to carry out the main heating operation. If the cooling load is larger, the control device determines to carry out the main cooling operation. By the compressors 110 in the outdoor unit 100 being driven, the air conditioning system starts to be operated.

[88] The main heating operation of the air conditioning system will now be explained with reference to FIG. 2.

[89] When the air conditioning system is operated in the main heating mode, the control device switches the 4- way valve 130 so that the refrigerant introduced into the outdoor unit 100 through the second refrigerant pipe 430 is sucked into the compressors 110 via the outdoor expansion valve 160 and the outdoor heat exchangers 120.

[90] At this time, the outdoor expansion valve 160, which is configured as an electronic expansion valve, is controlled to expand the refrigerant. The refrigerant expanded in the outdoor expansion valve 160 is evaporated in the outdoor heat exchangers 120 by being heat exchanged, and then flows into the accumulator 140 connected to the inlets of the compressors 110 and is temporarily stored in the accumulator 140. The accumulator 140 has functions of separating the refrigerant into gas refrigerant and liquid refrigerant, as well as adjusting the amount of refrigerant sucked into the compressors 110.

[91] Thereafter, the refrigerant sucked into the compressors 110 is compressed, and then is discharged. The refrigerant discharged from the compressors 110 is guided into the refrigerant distribution device 400 through the first refrigerant pipe 410.

[92] So as for the refrigerant to flow to the room intended to be heated, i.e., to the air handling unit 300 and the first indoor unit 210, the control device opens the first refrigerant control valve 421 of the first refrigerant pipe and the second refrigerant control valve 441 of the first refrigerant pipe.

[93] Then, the refrigerant is condensed while flowing through the air handling unit heat exchanger 330 and the indoor heat exchanger 211 of the first indoor unit 210 via the first refrigerant pipe 410. The air handling unit 300 and the first indoor unit 210 are operated in the heating mode. In order to prevent the refrigerant from flowing back through the third refrigerant pipe 450, the first refrigerant control valve 423 of the third refrigerant pipe and the second refrigerant control valve 443 of the third refrigerant pipe, connected with the air handling unit 300 and the first indoor unit 210, should be closed.

[94] The refrigerant passing through the air handling unit 300 and the first indoor unit 210 flows through the first refrigerant branch pipe 431 of the second refrigerant pipe, the second refrigerant branch pipe 433 of the second refrigerant pipe, and the second refrigerant pipe 430. At this time, a portion of the refrigerant flows into the second indoor unit 220 along the third refrigerant branch pipe 435 of the second refrigerant pipe. The remaining portion of the refrigerant is collected into the outdoor unit 100 through the second refrigerant pipe 430.

[95] As shown in FIG. 2, the third refrigerant control valve 463 of the third refrigerant pipe connected with the second indoor unit 220 is opened, and the third refrigerant control valve 461 of the first refrigerant pipe is closed. By this, a portion of the refrigerant passing through the first indoor unit 210 and the air handling unit 300, which are operated in the heating mode, flows to the second indoor unit 220 operated in the cooling mode through the second refrigerant pipe 430.

[96] Since the third refrigerant control valve 463 of the third refrigerant pipe is opened, the refrigerant passing through the second indoor unit 220 flows to the accumulator 140 through the third refrigerant pipe 450, and then is sucked into the compressors 110.

[97] Next, the main cooling operation of the air conditioning system will be explained with reference to FIG. 3.

[98] When the air conditioning system is operated in the main cooling mode, the control device controls the system so that a portion of the refrigerant discharged from the compressors 110 flows to the refrigerant distribution device 400 through the first refrigerant pipe 410 and the remaining portion of the refrigerant flows to the refrigerant distribution device 400 through the second refrigerant pipe 430 via the outdoor heat exchangers.

[99] The refrigerant flowing through the outdoor heat exchangers 120 is condensed. The condensed refrigerant is guided into the refrigerant distribution device 400 through the second refrigerant pipe 430 via the outdoor expansion valve 160. At this time, the outdoor expansion valve 160 is in a fully opened state.

[100] The control device opens the first refrigerant control valve 423 of the third refrigerant pipe and the second refrigerant control valve 443 of the third refrigerant pipe connected with the air handling unit 300 and the first indoor unit 210, which are operated in the cooling mode, and closes the first refrigerant control valve 421 of the first refrigerant pipe and the second refrigerant control valve 441 of the first refrigerant pipe.

[101] The control device opens the third refrigerant control valve 461 of the first refrigerant pipe connected with the second indoor unit 220, which is operated in the heating mode, and closes the third refrigerant control valve 463 of the third refrigerant pipe.

[102] By this, the refrigerant flowing through the second refrigerant pipe 430 is directed to the air handling unit 300 and the first indoor unit 210, which are operated in the cooling mode.

[103] The refrigerant flowing to the air handling unit 300 is guided into the air handling unit expansion valve 340 of the air handling unit 300, and is expanded. The expanded refrigerant is evaporated in the air handling unit heat exchanger 330, and absorbs ambient heat. Therefore, the air handling unit heat exchanger 330 serves as a cooling source. The evaporated refrigerant flows through the first refrigerant branch pipe 451 of the third refrigerant pipe, and is guided into the outdoor unit 100 through the third refrigerant pipe 450.

[104] Similarly, the refrigerant flowing to the first indoor unit 210 is guided into the indoor expansion valve 213 of the first indoor unit 210, and is expanded. The expanded refrigerant is evaporated in the indoor heat exchanger 211, and absorbs ambient heat. Therefore, the indoor heat exchanger 211 serves as a cooling source. The evaporated refrigerant flows through the second refrigerant branch pipe 453 of the third refrigerant pipe, and is guided into the outdoor unit 100 through the third refrigerant pipe 450.

[105] The refrigerant thus guided into the outdoor unit 100 is sucked into the compressors 110 via the accumulator 140, and then is compressed again.

[106] As shown in FIG. 3, when the second indoor unit 220 is operated in the heating mode, the refrigerant flows into the second indoor unit 220 through the third refrigerant branch pipe 415 of the first refrigerant pipe. The refrigerant flows through the indoor heat exchanger 221 of the second indoor unit 220, and is condensed. In order to prevent the refrigerant from flowing back through the third refrigerant pipe 450, the third refrigerant control valve 463 of the third refrigerant pipe should be closed.

[107] The refrigerant passing through the second indoor unit 220 operated in the heating mode flows into the air handling unit 300 and the first indoor unit 210, which are operated in the cooling mode, through the second refrigerant pipe 430.

[108] The present invention is not limited to the above-described embodiments, and can be applied to the main cooling operation mode or the main heating operation mode using the plural outdoor units.

[109] From the state as shown in FIG. 2, if the first refrigerant control valve 421 of the first refrigerant pipe 410, the second refrigerant control valve 441 of the first refrigerant pipe and the third refrigerant control valve 461 of the first refrigerant pipe are opened, and the first refrigerant control valve 423 of the third refrigerant pipe 450, the second refrigerant control valve 443 of the third refrigerant pipe and the third refrigerant control valve 463 of the third refrigerant pipe are closed, the first indoor unit 210, the second indoor unit 220 and the air handling unit 300 are totally operated in the heating mode.

[110] Conversely, from the state as shown in FIG. 3, if the first refrigerant control valve

421 of the first refrigerant pipe 410, the second refrigerant control valve 441 of the first refrigerant pipe and the third refrigerant control valve 461 of the first refrigerant pipe are closed, and the first refrigerant control valve 423 of the third refrigerant pipe 450, the second refrigerant control valve 443 of the third refrigerant pipe and the third refrigerant control valve 463 of the third refrigerant pipe are opened, the first indoor unit 210, the second indoor unit 220 and the air handling unit 300 are totally operated in the cooling mode.

[I l l] Hereinafter, a communication link among the outdoor unit, the indoor unit and the air handling unit in the air conditioning system according to the present invention will be explained with reference to FIG. 4.

[112] The control device provided in the air conditioning system according to the present invention includes an outdoor unit micom 510 to control all circumstances of the outdoor unit, an indoor unit micom 560 to control all circumstances of the indoor unit, an air handling unit micom 590 to control all circumstances of the air handling unit, and a communication line 530 for communication among the outdoor unit, the indoor unit and the air handling unit.

[113] The control device further includes an outdoor unit communication circuit part 520 to connect the outdoor unit micom 510 and the communication line 530, an indoor unit communication circuit part 550 to connect the indoor unit micom 560 and the communication line 530, and an air handling unit communication circuit part 570 to connect the air handling unit micom 590 and the communication line 530.

[114] Here, the communication line includes both wire and wireless communication lines. In a case where the communication line is configured as only the wireless communication line, the outdoor unit communication circuit part 520, the indoor unit communication circuit part 550 and the air handling unit communication circuit part 570 are constituted so as to directly communicate with each other.

[115] The outdoor unit micom 510 and the outdoor unit communication circuit part 520 are mounted in the outdoor unit 100, the indoor unit micom 560 and the indoor unit communication circuit part 550 are mounted in the indoor unit 200, and the air handling unit micom 590 and the air handling unit communication circuit part 570 are mounted in the air handling unit 300.

[116] The outdoor unit micom 510 includes an outdoor unit address setting part 511 capable of setting addresses of the plural indoor units and air handling units, and an outdoor unit data converting part 513 to convert data transmitted/received between the outdoor unit and the indoor unit/air handling unit adequately for a standard of the outdoor unit.

[117] The outdoor unit address setting part 511 transmits and receives information to/from the outdoor unit data converting part 513 through the communication therewith, and the outdoor unit data converting part 513 transmits and receives information to/from the outdoor unit communication circuit part 520 through the communication therewith. Based on the data transmitted and received through the outdoor unit data converting part 513, the outdoor unit address setting part 511 sets new addresses with respect to the indoor unit and the air handling unit which are intended to be operated.

[118] The air handling unit 300 is mounted with an air handling unit memory 540 which stores information of air handling unit 300. The air handling unit memory 540 includes an air handling unit ID number storing part 583 which stores an ID number given to the air handling unit in its manufacturing process, and an air handling unit address storing part 581 which stores a new address given by the outdoor unit address setting part 511.

[119] The air handling unit micom 590 includes an air handling unit data converting part 593 which arranges the data transmitted and received and converts the data adequately for a standard of the air handling unit, and an air handling unit address setting part 591 which transmits a new address given to the air handling unit 300 by the outdoor unit address setting part 511 to the air handling unit address storing part 581 and sets the same.

[120] The air handling unit address setting part 591 also has a function of reading the ID number stored in the air handling unit ID number storing part 583 and transmitting the ID number to the air handling unit data converting part 593.

[121] The indoor unit 200 is mounted with an indoor unit memory 540. The indoor unit memory 540 includes an indoor unit ID number storing part 541 which stores an ID number given to the indoor unit in its manufacturing process, and an indoor unit address storing part 543 which stores a new address given by the outdoor unit address setting part 511.

[122] The indoor unit micom 560 includes an indoor unit data converting part 563 which arranges the data transmitted and received and converts the data adequately for a standard of the indoor unit, and an indoor unit address setting part 561 which transmits a new address given to the indoor unit 200 by the outdoor unit address setting part 511 to the indoor unit address storing part 543, reads the ID number stored in the indoor unit ID number storing part 541, and transmits the ID number to the indoor unit data converting part 563.

[123] Hereinafter, a control method of the air conditioning system according to the present invention will be explained with reference to FIGs. 4 and 5. More particularly, a process of setting new addresses of the indoor unit and the air handling unit by the control device provided in the present invention will be explained.

[124] If power is applied to the indoor unit and the air handling unit to air condition a room, the outdoor unit micom detects the indoor unit and the air handling unit to which power is applied. The moment power is applied to the indoor unit and the air handling unit to be air conditioned, the indoor unit and the air handling unit are electrically connected to the outdoor unit at step SlO.

[125] At the same time, the load sensor senses cooling/heating load of the room intended to be air conditioned, and transmits data of the sensed load to the control device.

[126] The control device reads the ID numbers of the indoor unit and the air handling unit which are operated at step S30, and gives new addresses according to the ID numbers to the indoor unit and the air handling unit at step S50. The control device determines whether the new addresses are completely set at step S70, and controls the indoor unit and the air handling unit according to the new addresses given to the indoor unit and the air handling unit. At this time, the control device controls the indoor unit and the air handling unit corresponding to the cooling/heating load of the room, based on the data sensed by the load sensor.

[127] A process of giving the new addresses to the indoor unit and the air handling unit by the control device will now be explained.

[128] In order to set the addresses of the indoor unit and the air handling unit, the outdoor unit address setting part 511 transmits an address setting starting signal, which informs the starting of the address setting, to the outdoor unit data converting part 513. The outdoor unit data converting part 513 converts the address setting starting signal adequately for a standard of the communication line, and the converted address setting starting signal is transmitted to the indoor unit communication circuit part 550 and the air handling unit communication circuit part 570 via the outdoor unit communication circuit part 520 and the communication line 530.

[129] The address setting starting signal transmitted to the indoor unit communication circuit part 550 and the air handling unit communication circuit part 570 flows through the indoor unit data converting part 563 and the air handling unit data converting part 593, and is respectively converted into a signal adequate for the standards of the indoor unit and the air handling unit.

[130] The address setting starting signal converted adequately for the indoor unit and the air handling unit is transmitted to the indoor unit address setting part 561 and the air handling unit address setting part 591. The indoor unit address setting part 561 and the air handling unit address setting part 591 read the respective ID numbers of the indoor unit and the air handling unit, and transmit the ID numbers to the outdoor unit address setting part 511.

[131] Thereafter, the outdoor unit address setting part 511 gives new addresses to the indoor unit and the air handling unit according to the ID numbers of the indoor unit and the air handling unit. Then, the indoor unit address setting part 561 and the air handling unit address setting part 591 store the new addresses in the indoor unit address storing part 543 and the air handling unit address storing part 581, respectively.

[132] Here, the process of setting the new address with respect to the ID number of the air handling unit is defined as a first address setting process, and the process of setting a new address with respect to the ID number of the indoor unit is defined as a second address setting process. The first address setting process and the second address setting process may be carried out simultaneously, or may be carried out in sequence.

[133] The control device determines whether the address setting with respect to the air handling unit and the indoor unit has been completed through the above-described process. If the control device determines that the address setting has not been completed, the control device carries out the above-described process again. If the address setting with respect to the air handling unit and the indoor unit is completed, the outdoor unit communicates with the indoor unit and the air handling unit which are set with the new addresses, and the indoor unit and the air handling unit are selectively or simultaneously operated based on the load sensed by the load sensor.

[134] Hereinafter, an air conditioning system according to another exemplary embodiment of the present invention will be described with reference to FIG. 6.

[135] Different from the preceding embodiment, an air conditioning system of this embodiment includes plural outdoor units (a first outdoor unit 1100, a second outdoor unit 1200, a third outdoor unit 1300 and a fourth outdoor unit 1400) and one air handling unit 2000. The air conditioning system may further include a refrigerant distribution device 3200 to control the refrigerant flow between the plural outdoor units and the one air handling unit 2000, and a control device 3100 to control communication between the plural outdoor units and the one air handling unit.

[136] The air handling unit includes plural divided heat exchangers (a first heat exchanger 2110, a second heat exchanger 2120, a third heat exchanger 2130 and a fourth heat exchanger 2140) which are respectively given with ID numbers so as to be operated individually by the control device according to cooling/heating load of the room. More particularly, the first heat exchanger 2110, the second heat exchanger 2120, the third heat exchanger 2130 and the fourth heat exchanger 2140 correspond to the first outdoor unit 1100, the second outdoor unit 1200, the third outdoor unit 1300 and the fourth outdoor unit 1400, respectively, and are controlled individually according to the cooling/heating load of the room.

[137] Capacities of the respective outdoor units may be varied according to the cooling/ heating load of the room. Also, the plural divided heat exchangers and outdoor units may be operated alternately according to the cooling/heating load of the room. For example, on the assumption that the load of the room is 100, the maximum capacity of the first heat exchanger 2110 is 100 and the maximum capacity of the second heat exchanger 2120 is 200, the first heat exchanger 2110 and the second heat exchanger 2120 can be operated alternately in order to satisfy the load of the room. Here, the second outdoor unit 1200 connected with the second heat exchanger 2120 may be configured as a capacity- variable outdoor unit.

[138] A part of the plural divided heat exchangers may be used for the cooling operation, and the remaining part of the plural heat exchangers may be used for the heating operation. Accordingly, it is not necessary to carry out an additional defrosting operation, and thus there is no problem of heating interruption or deterioration of heating capacity. Industrial Applicability

[139] The present invention relates to an air conditioning system and a control method thereof, and more particularly, to an air conditioning system and a control method thereof capable of efficiently operating the system.

Claims

[1] An air conditioning system comprising: at least one outdoor unit; at least one air handling unit connected with the outdoor unit to cool/heat or ventilate a room; and a control device to recognize an identification number of the air handling unit and give a new address to the air handling unit through communication with the air handling unit.

[2] The air conditioning system according to claim 1, further comprising: at least one indoor unit connected with the outdoor unit to cool/heat the room selectively or simultaneously with the air handling unit.

[3] The air conditioning system according to claim 2, further comprising: a load sensor to sense cooling/heating load of the room to control the air handling unit and the indoor unit according to the cooling/heating load of the room.

[4] The air conditioning system according to claim 2, further comprising: a refrigerant distribution device to control refrigerant flowing through the outdoor unit, the air handling unit and the indoor unit, the refrigerant distribution device being controlled by the control device.

[5] The air conditioning system according to claim 1, wherein the control device selectively or simultaneously controls the air handling unit according to the new address of the air handling unit.

[6] The air conditioning system according to claim 2, wherein the control device recognizes an identification number of the indoor unit and gives a new address to the indoor unit to control the air handling unit and the indoor unit.

[7] The air conditioning system according to claim 1, wherein the air handling unit includes plural divided heat exchangers, and wherein the plural divided heat exchangers are respectively given with identification numbers so as to be operated individually by the control device according to cooling/heating load of the room.

[8] The air conditioning system according to claim 7, wherein the at least one outdoor unit includes plural outdoor units, and wherein the plural outdoor units are operated alternately corresponding to the plural divided heat exchangers.

[9] The air conditioning system according to claim 8, wherein a part of the plural divided heat exchangers is controlled to be used for cooling operation, and the remaining part of the plural divided heat exchangers is controlled to be used for heating operation. [10] The air conditioning system according to claim 7, wherein the outdoor unit has a variable capacity in accordance with capacities of the divided heat exchangers. [11] A method for controlling an air conditioning system, the method comprising: recognizing an identification number with respect to at least one air handling unit connected with at least one outdoor unit for cooling/heating or ventilating a room; and setting a new address with respect to the recognized identification number of the air handling unit. [12] The method according to claim 11, further comprising: operating selectively or simultaneously the air handling unit in accordance with the new address of the air handling unit. [13] The method according to claim 11, further comprising: controlling at least one indoor unit connected with the outdoor unit independently from the air handling unit. [14] The method according to claim 13, further comprising: controlling refrigerant flowing through the outdoor unit, the air handling unit and the indoor unit which are operated according to a command from a control device. [15] The method according to claim 13, wherein the step of controlling the indoor unit includes recognizing an identification number with respect to the indoor unit, and setting a new address with respect to the identification number of the indoor unit. [16] The method according to claim 15, further comprising: sensing cooling/heating load of the room to control simultaneously or selectively the air handling unit and the indoor unit. [17] The method according to claim 12, wherein the step of operating the air handling unit includes operating individually plural divided heat exchangers provided in the air handling unit in accordance with cooling/heating load of the room. [18] The method according to claim 17, wherein the at least one outdoor unit includes plural outdoor units, and wherein at the step of operating the plural divided heat exchangers, the plural outdoor units are operated alternately corresponding to the plural divided heat exchangers. [19] The method according to claim 17, wherein at the step of operating the plural divided heat exchangers, a part of the plural divided heat exchangers is operated in a cooling mode, and the remaining part of the plural divided heat exchangers is operated in a heating mode. [20] The method according to claim 17, wherein at the step of operating the plural divided heat exchangers, the outdoor unit has a variable capacity in accordance with capacities of the divided heat exchangers.