AIR CONDITIONING SYSTEM AND CONTROLLING METHOD USING THE SAME

Abstract

The present invention discloses an air conditioning (AC) system, which comprises an indoor ventilation device, at least one air-supply chain and at least one cascading duct. The indoor ventilation device comprises a main blower. Each of the at least one air-supply chain comprises “n” sub air-supply regions each having at least one air inlet and at least one air outlet. Each of the at least one cascading duct is used to one-by-one cascade each of the “n” sub air-supply regions by sequentially connecting with the at least one air inlet and/or the at least one air outlet of each of the “n” sub air-supply regions, wherein “n” is an integer and “n”>1 and at least one of the at least one cascading duct is a partition wall connecting any two sub air-supply regions.

Description

FIELD OF THE INVENTION

The present invention relates to an air conditioning (AC) system and controlling method using the same, and in particular, is related to an AC system applied in a field of AC, for improving the conventional AC system.

BACKGROUND OF THE INVENTION

Please refer to FIGS. 1-2. FIG. 1 is a schematic diagram of the pipeline configuration of a conventional air conditioning (AC) system 10; FIG. 2 is a schematic diagram of the architecture of a conventional air conditioning (AC) system 10. In the conventional air-conditioning system 10, an indoor ventilation device 195 is used for air circulation in the indoor space, and the main blower 110 is used to introduce outdoor air 190 (generally speaking, the outdoor air 190 is an area where a building communicates with the outdoors, such as a balcony) and exchange with indoor air to take away harmful substances existing in indoor air, such as carbon dioxide and formaldehyde. The air is delivered to each sub air-supply region 130 through the air inlet 131 through the inlet-air duct 167 in parallel, and then sent back to the indoor ventilation device 195 through the air outlet 132 through the outlet-air duct 169. Exhausted air 192 is also discharged as appropriate. Basically, the indoor ventilation device mentioned in the present invention is commonly known as a total heat exchanger. Although it has a heat exchange function, its main purpose is to maintain indoor air quality and is not suitable for temperature adjustment. Because the length of the inlet-air duct 167 and the outlet-air duct 169 will affect the air volume (generally, the longer the pipeline, the more serious the loss of the air volume), that the reason why the indoor ventilation device 190 is usually installed in the center of the indoor space (as shown in FIG. 1), to avoid the problem of uneven distribution of air volume in each space. When design an indoor space, in order to be beautiful, a ceiling is usually used to cover it (the duct, pipeline, the ventilation device etc.), which will cause the height of the local or all of the indoor space to decrease. According to statistics, when the indoor height drops below 2.4 meters, it will cause pressure and discomfort to people. Please refer to FIG. 3, a schematic diagram of the air inlet duct 167 and the beam 168. Generally, indoor spaces usually have beams, and the air inlet duct 167 can usually be handled in two ways: 1. Make a hole on the beam; 2. Form the air inlet duct 167 into a U shape (as shown in FIG. 3); 3. Use a cross-beam flat duct (a flat space is formed under the beam to allow air to flow). Although the first method is feasible, considering the building regulations and structural safety, this treatment is usually not recommended; the second and third methods will cause a large amount of air loss, resulting in insufficient ventilation or the need for the rear connection space or retrofit a larger all-heat exchanger.

Furthermore, because under the same air volume, the smaller the pipe diameter of the air duct, the greater the air loss. Generally, 6-inch (approximately 15 cm) air ducts are recommended for the indoor space of homes. If the second method is adopted, the height of the ceiling needs to be lowered by 20-30 cm from below the beam 168 (it may even be necessary to lower the ceiling).

However, the height of the indoor space is very important for the quality of living. Therefore, if the air duct can be reduced or even eliminated, there is no need to reduce the height of the ceiling due to the installation of the air duct. It is important to note that the air ducts (inlet-air duct 167 and outlet-air duct 169) of the conventional air conditioning (AC) air conditioning system 10 usually need to cover the entire indoor space (as shown in FIG. 1).

Therefore, the conventional technology has below disadvantages: 1. The use of a large number of air ducts causes an increase in cost, difficulty in construction, and a decrease in ceiling height in most indoor spaces; 2. The beam duct will cause the ceiling to decrease (U-shaped duct) or loss of air volume (cross-beam flat duct).

Hence, it is needed to provide an air conditioning (AC) system and the controlling method of using the same, for solving the aforementioned technical problem.

SUMMARY OF THE INVENTION

In order to solve the aforementioned technical problems of the conventional art, the object of the present invention is to provide an air conditioning (AC) system and the controlling method of the same. First, multiple sub air-supply regions are connected through multiple cascading ducts to supply air sequentially. Compared with the conventional parallel air ducts (the air duct in each sub air-supply region needs to be connected to the indoor ventilation device), most of the air ducts are reduced. The use of (the length of the duct only needs to be connected to the adjacent sub air-supply region); then further by setting the cascading ducts in the partition wall between each two adjacent sub air-supply regions, the need of duct for each two adjacent sub air-supply regions is further greatly eliminated. There is no need to use a large number of air ducts and reduce the height of the ceiling as in the conventional AC system.

In order to achieve the above objective, the present invention provides an AC system, which comprises an indoor ventilation device, at least one air-supply chain and at least one cascading duct.

The indoor ventilation device comprises a main blower which is used for receiving an outdoor air. Each of the at least one air-supply chain comprises “n” sub air-supply regions, each of the sub air-supply regions comprising at least one air inlet and at least one air outlet. Each of the at least one cascading duct is used to one-by-one cascade each of the “n” sub air-supply regions by sequentially connecting with the at least one air inlet and/or the at least one air outlet of the “n” sub air-supply regions of each of the at least one air-supply chain. The at least one air inlet of one of the sub air-supply regions only connecting with one cascading duct of the at least one cascading duct and the at least one air outlet of the one of the sub air-supply regions only connecting with another cascading duct of the at least one cascading duct. Wherein “n” is an integer and “n”>1, air inlet of a first sub air-supply region of the “n” sub air-supply regions is connected with an air outlet of the main blower via the at least one cascading duct, an air inlet of a nth sub air-supply region of the “n” sub air-supply regions is connected with an air outlet of a (n−1)th sub air-supply region of the “n” sub air-supply regions, and an air outlet of the nth sub air-supply region of the “n” sub air-supply regions is connected with an exhausted air duct and return to the indoor ventilation device.

In one preferred embodiment, at least one of the at least one cascading duct is a partition wall connecting any two sub air-supply regions.

In one preferred embodiment, when “n” is larger than 2, except for the first sub air-supply region and the nth sub air-supply region of the “n” sub air-supply regions, the at least one air inlet of mth sub air-supply regions of the “n” sub air-supply regions is connected with the at least one air outlet of (m−1)th sub air-supply regions of the “n” sub air-supply regions and the at least one air outlet of the mth sub air-supply regions of the “n” sub air-supply regions is connected with the at least one air inlet of (m+1)th sub air-supply regions of the “n” sub air-supply regions, “m” is an integer and “n” is larger than “m”, “m” is larger than 1.

In one preferred embodiment, the AC system further comprises a sub AC unit disposed inside of the each of the “n” sub air-supply regions.

In one preferred embodiment, the AC system comprises at least one sub blower disposed in at least one cascading duct.

In order to achieve the above objective, the present invention further provides a controlling method for an AC system, which comprises: First, an outdoor air is transported through a main blower of an indoor ventilation device to at least one air-supply chain; then, at least one air inlet and/or at least one air outlet of “n” sub air-supply regions of the at least one air-supply chain are sequentially connected through at least one cascading duct, each of the “n” sub air-supply regions are cascaded one-by-one, wherein “n” is an integer and “n”>1; then, the air is sequentially transported to each of the “n” sub air-supply regions through the at least one cascading duct; then, air is transported back to the indoor ventilation device by connecting an exhausted duct with air outlet of the nth sub air-supply region. Wherein the at least one air inlet of one of the sub air-supply regions is only connected with one cascading duct of the at least one cascading duct and the at least one air outlet of the one of the sub air-supply regions is only connected with another cascading duct of the at least one cascading duct.

In one preferred embodiment, a sub AC unit is disposed inside each of the “n” sub air-supply regions to homogenize the air in the sub air-supply region.

In one preferred embodiment, the indoor ventilation device is disposed outside the at least one air-supply chain.

In one preferred embodiment, at least one of the at least one cascading duct is a partition wall connecting any two sub air-supply regions.

In one preferred embodiment, the AC system further comprises at least one sub blower disposed in at least one cascading duct.

Compared with the conventional arts, the present invention merely uses one blower to apply into the method of using at least one cascading duct for connecting multiple sub air-supply regions. Compared with the conventional parallel air ducts (the air duct in each sub air-supply region needs to be connected to the indoor ventilation device), most of the air ducts are reduced. The use of (the length of the duct only needs to be connected to the adjacent sub air-supply region); then further by setting the cascading ducts in the partition wall between each two adjacent sub air-supply regions, the need of duct for each two adjacent sub air-supply regions is further greatly eliminated. There is no need to use a large number of air ducts and reduce the height of the ceiling as in the conventional AC system.

DESCRIPTION OF THE DIAGRAMS

FIG. 1 is a schematic diagram of the pipeline configuration of the conventional AC system;

FIG. 2 is a schematic diagram of the architecture of the conventional AC system of FIG. 1;

FIG. 3 a schematic diagram of the air inlet duct and the beam;

FIG. 4 is a schematic diagram of an AC system according to the present invention;

FIG. 5 is an enlarged diagram of portion “A” of FIG. 4;

FIG. 6 is a schematic diagram of the architecture of an AC system according to the present invention; and

FIG. 7 is a flow diagram of a controlling method for an AC system according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the embodiments is given by way of illustration with reference to the specific embodiments in which the invention may be practiced. The terms such as “up”, “down”, “front”, “back”, “left”, “right”, “inside”, “outside”, “side”, etc., The direction of the diagram. Accordingly, the use of a directional term is used to describe and to understand the present invention and is not intended to limit the invention.

Please refer to FIGS. 4-6. FIG. 4 is a schematic diagram of an AC system 100 according to the present invention; FIG. 5 is an enlarged diagram of portion “A” of FIG. 4; FIG. 6 is a schematic diagram of the architecture of an AC system 100 according to the present invention. The AC system 100 comprises an indoor ventilation device 195, at least one air-supply chain 150 and at least one cascading duct 165. There are sub AC units 125 in FIG. 4 but no sub AC units 125 in FIG. 6 which is merely for illustration, not limit.

The indoor ventilation device 195 comprises a main blower 110 which is used for receiving an outdoor air 190. Generally, the indoor ventilation device 195 comprises basic filter unit (not showed), with the demand change, the filter unit might be used for eliminating toxic gas such as formaldehyde. Basically, the indoor ventilation device 195 does not have the function of temperature adjustment. The main function is to provide the indoor space to maintain the concentration of carbon dioxide and other harmful human gases in the indoor space under sort of a closed condition (doors and windows are closed). In this preferred embodiment, a home space is used for illustration, and only the area in the lower left corner (the area where the indoor ventilation device 195 is located) is a balcony (non-closed space). The air inlet 151 of the air-supply chain region 150 communicates with the main blower 110. The air-supply chain region 150 includes 6 sub air-supply regions 130 (all in a Para-closed state), and each sub air-supply region 130 includes an air inlet 131 and an air outlet 132 (can be added according to the real situation).

Each of the at least one cascading duct 165 is used to one-by-one cascade each of the “n” sub air-supply regions 130 for providing air by sequentially connecting with the at least one air inlet 131 and/or the at least one air outlet 132 of the “n” sub air-supply regions 130 of each of the at least one air-supply chain 150. The at least one cascading duct 165 sequentially cascades corresponding air outlet 132 and air inlet 131 of every two sub air-supply regions 130. FIG. 6 shows two air-supply chains 150 connected in parallel at the front end (independent air inlet duct 167 can also be used at the front); FIG. 4 shows one air-supply chain 150 for Illustrating the present invention.

Preferably, multiple air inlets 131 and/or multiple air outlets 132 can be provided in each sub air-supply region 130 as appropriate, and it is important to note that multiple air inlets 131 and/or multiple air outlets 132 are connected to the cascading duct 165 in parallel.

It is important to note that each sub air-supply region 130 in the present invention is connected to only two cascading ducts 165, and the two cascading ducts 165 are respectively connected to multiple air inlets 131 and/or multiple air outlets 132. Therefore, if there are more than two cascading ducts 165 in one sub air-supply region 130 (that is, more than one cascading duct 165 is used for air-out or air-in), it is possible to cause the two of the sub air-supply regions 130 which are connected with the sub air-supply region 130 has insufficient or excessive air intake (assuming that one cascading duct 165 is used for air-in; two cascading ducts 165 are used for air-out). Therefore, compared with the conventional art, the present invention can maintain the air exchange rate of each sub air-supply region 130 by restricting one-in and one-out of each sub-air supply area 130 (one cascading duct 165 is used for air-in; one cascading duct 165 is used for air-out).

Preferably, “n” is an integer and “n”>1, air inlet 131 of a first sub air-supply region 130 of the “n” sub air-supply regions 130 is connected with an air outlet 132 of the main blower 110 via the at least one cascading duct 165, an air inlet 131 of a nth sub air-supply region 130 of the “n” sub air-supply regions 130 is connected with an air outlet 132 of a (n−1)th sub air-supply region 130 of the “n” sub air-supply regions 130, and an air outlet 132 of the nth sub air-supply region 130 of the “n” sub air-supply regions 130 is connected with an exhausted air duct 170 and return to the indoor ventilation device 195.

When “n” is larger than 2, except for the first sub air-supply region 130 and the nth sub air-supply region 130 of the “n” sub air-supply regions, the at least one air inlet 131 of mth sub air-supply regions 130 of the “n” sub air-supply regions 130 is connected with the at least one air outlet 132 of (m−1)th sub air-supply regions 130 of the “n” sub air-supply regions 130 and the at least one air outlet 132 of the mth sub air-supply regions 130 of the “n” sub air-supply regions 130 is connected with the at least one air inlet 131 of (m+1)th sub air-supply regions 130 of the “n” sub air-supply regions 130, “m” is an integer and “n” is larger than “m”, “m” is larger than 1.

In FIG. 4, starting from the indoor ventilation device 195, air is sequentially delivered to the five sub air-supply regions 130 in a counterclockwise manner. When each sub air-supply region 130 is in a Para-closed state, air can be delivered to each sub air-supply region 130 in sequence. In this state, the cascading ducts 165 (air duct) only needs to connect two adjacent sub air-supply regions 130, which can reduce the use of a large number of air ducts compared with the conventional art which using a large number of air inlet ducts and air outlet ducts. However, despite reducing the use of a large number of air ducts, the ceiling height still cannot be increased.

In view of this, a cascading duct 165 can be arranged in the partition wall 180 of the adjacent sub air-supply regions 130, and there is no need to use the air duct (series channel 165) connecting the adjacent sub air-supply regions 130. On the premise that the adjacent sub air-supply regions can transport air without air ducts, the height of the ceiling can be effectively increased.

Finally, referring to FIG. 5 again, a sub blower 120 can be further installed in the cascading duct 165 to enhance the effect of ventilation. Taking FIG. 6 as an example, a sub blower 120 can be installed on some of the partition walls 180 as appropriate. Preferably, the sub blower 120 can be a blower or a fan, because the SERIES air-supply chain (one in and one out) adopted in the present invention will not cause uncomfortable noise according to the real implementation of the inventor. And preferably, the blower can be completely installed in the cascading ducts 165 (ie, the partition wall 180), without connecting with ceiling for implementation.

In FIG. 6, the AC system 100 includes two air-supply chains 150. Each air-supply chain 150 includes five sub air-supply regions 130. (I.e. n=5, m=2-4) Taking the air-supply chain 150 located in the upper half as an example, the “n” sub air-supply regions 130 include a first sub air-supply region 130 (the leftmost one) and at least one a second sub air-supply area (the rest). The at least one air inlet 131 of the first sub air-supply region 130 communicates with the air inlet 151 of the air-supply chain 150 (that is, a part of the at least one cascading duct 165); then, continue to go through the at least one cascading duct 165. The at least one air outlet 132 of the first sub air-supply region 130 is connected to the at least one air inlet 131 of a second sub air-supply region 130 (second from the left) adjacent to the first sub air-supply region 130; and so on, finally, at the at least one air outlet 132 of the rightmost sub air-supply region 130 is discharged to an exhausted air duct 170 and sent back to the indoor ventilation device. Therefore, each of the at least one cascading duct 165 is sequentially connected to the at least one air outlet 132 and/or the at least one air inlet 131 of each of the “n” sub air-supply regions 130 in the corresponding air-supply chain 150, and then one by one, each of the “n” sub air-supply regions 130 is connected in SERIES to provide the required indoor ventilation. In FIG. 6, the exhausted air duct 170 is connected to the two air supply chains 150 located in the upper and lower halves can be selectively connected or sent back to the indoor ventilation device 195 respectively. The following preferred embodiments also as in this preferred embodiment, it will not be repeated.

Preferably, a sub AC unit 125 can also be provided in each sub air-supply region 130. The sub AC unit 125 here is generally common air-condition, and mainly provides the function for changing the temperature. In the preferred embodiment, each sub AC unit 125 is independent, but it can also be one-to-multiple AC, which is not limited. Preferably, the sub AC unit 125 does not have a ventilation function. Thereby, the indoor ventilation device 195 is responsible for ventilation and the sub-air conditioning unit 125 is responsible for temperature adjustment to maintain the indoor air quality to the greatest extent. However, in a further step, the indoor ventilation device 195 or the sub blower 120 may also have a temperature adjustment function, and it is not limited thereto.

In FIG. 4, it can be seen that when the indoor ventilation device 195 is connected to the sub air-supply region 130 on the right by the balcony at the lower left corner, the air duct is still used. In actual operation, since the balcony is generally connected to the toilet or kitchen, Therefore, people are relatively insensitive to the height of the ceiling, so in the present invention, the air duct is still used in this area, because as long as it enters any indoor space (sub air-supply region 130), it can be performed by a SERIES air-supply chain to ventilating adjacent sub air-supply regions 130.

Comparing FIG. 4 and FIG. 1, it can be clearly understood that the inlet-air duct 167 in FIG. 4 is only a short section, and the length of the exhausted air duct 170 (equivalent to the outlet-air duct 169) is also very long. The short, saved air duct not only reduces material costs, but also saves labor and reduces ceiling height because it does not require a large number of conventional air duct installations.

In a preferred embodiment, it is assumed that the balcony, the kitchen, and the toilet are respectively from left to right. Generally speaking, the air in the toilet needs to be ventilated independently of other indoor spaces. Therefore, the partition wall 180 can be used as the cascading duct 165 in the toilet area; that is, the toilet part still uses the air duct. However, as in the previous paragraph, it shows that people are less sensitive to the ceiling height of the toilet (or kitchen). Even so, the effect of increasing the ceiling height and reducing the installation of air ducts in the ceiling can still be achieved in the remaining main living spaces. In a preferred case, at least one cascading duct 165 adopts in a partition wall 180 and is provided with a sub AC unit 125. Because the temperature adjustment is performed by the sub AC unit 125 after the air enters each sub air-supply region 130, energy loss can be reduced (the adjusted temperature air does not need to be transported over a long distance), so that the temperature of all sub air-supply regions 130 can be consistent with the set value. At the same time, the sub AC unit 125 can simultaneously homogenize the air in the sub air-supply region 130 by blowing out the adjusted air. However, in a better case, each sub air-supply region 130 of the air-supply chain 150 is in an ideal closed state (air can only be delivered through the air inlet 131 and the air outlet 132, and the sub AC unit 125 is also not for ventilation), the air will naturally form a flow direction (the arrow direction in the fig.), because the pressure is closer to the internal ventilation device 195 (such as the first sub air-supply region 130 on the right side of the balcony).); However, in actual situations, each sub air-supply region will not be completely sealed, so arranging the sub blower 120 in the cascading duct 165 can effectively transport the air from one sub air-supply region 130 to another sub air-supply region 130.

Preferably, because there is no need to consider the air volume attenuation caused by the length of the air duct and the problem of different air volumes in different sub air-supply regions caused by different lengths of air ducts, the indoor ventilation device 195 can be installed outside of the at least one air-supply chain, such as the above example, can be set in where communicates with the outdoors, such as balconies, without affecting the ceiling height of the indoor space (sub air-supply region). Taking FIG. 4 as an example, the indoor ventilation device 195 can even be installed against the partition wall 180 between the balcony (the first left in the lower row) and the kitchen (the second left in the lower row) to save the inlet-air duct 167; It is also possible to install the indoor ventilation device 195 against the partition wall 180 between the balcony (the first left in the lower row) and the sub air-supply region above the balcony to save the outlet-air duct 169. That is, if it is a general industrial or commercial space (toilet, kitchen, etc., independent exhaust is required to avoid affecting the work space), there is no need to use air ducts at all, and the air transmission to the adjacent sub air-supply region 130 is completely dependent on the partition wall 180. And because each sub air-supply region 130 in the present invention adopts unidirectional serial connection to connect adjacent sub air-supply regions, to a certain extent, when the air supply volume of the main fan 110 is large enough, even if the air transmission is only done by the cascading ducts 165 in the partition wall 180, air can also be delivered to each sub air-supply region 130 in sequence. (As shown in FIG. 4, it will be delivered to each sub air-supply region 130 in a counterclockwise manner from the balcony in the lower left corner)

FIG. 7 is a flow diagram of a controlling method for an AC system according to the present invention. For the devices mentioned in this controlling method, please refer to FIGS. 3-6, which will not be repeated.

Step S01, an outdoor air 190 is transported through a main blower 110 of an indoor ventilation device 195 to at least one air-supply chain 150; then, step S02, at least one air inlet 131 and/or at least one air outlet 132 of “n” sub air-supply regions 130 of the at least one air-supply chain 150 are sequentially connected through at least one cascading duct 165, each of the “n” sub air-supply regions 130 are cascaded one-by-one, wherein “n” is an integer and “n”>1; then, step S03, the air 190 is sequentially transported to each of the “n” sub air-supply regions 130 through the at least one cascading duct 165; then, step S04, a sub AC unit 125 is disposed inside each of the “n” sub air-supply regions 130 to homogenize the air 190 in the sub air-supply region 130; then, step S05, the air is transported back to the indoor ventilation device 195 by connecting an exhausted duct 170 with air outlet 132 of the nth sub air-supply region 130.

The at least one air inlet 131 of one of the sub air-supply regions 130 is only connected with one cascading duct 165 of the at least one cascading duct 165 and the at least one air outlet 132 of the one of the sub air-supply regions 130 is only connected with another cascading duct 165 of the at least one cascading duct 165.

Generally speaking, to evaluate the operation of an air conditioning system, all doors are closed as the design standard. For example, in FIG. 4, after all the doors are closed, air can be transmitted to each space (sub air-supply region 130) basically in a counterclockwise direction.

Compared with the conventional art, the present invention only needs to sequentially connect a plurality of sub air-supply regions with a plurality of cascading ducts by a fan to supply air. Compared to the conventional Parallel air ducts (air pipe of each sub air-supply region needs to be connected to the indoor ventilation device), the present invention reduces the use of most air pipes (the length of the air pipe only needs to be connected to the adjacent sub air-supply regions); then further by setting the cascading ducts in the partition walls of the adjacent sub air-supply regions, the air ducts needed by the adjacent sub air-supply regions are further removed significantly. There is no need to use a large number of air ducts and reduce the height of the ceiling as in the conventional AC system.

As described above, although the present invention comprises been described with the preferred embodiments thereof, those skilled in the art will appreciate that various modifications, additions, and substitutions are possible without departing from the scope and the spirit of the invention. Accordingly, the scope of the present invention is intended to be defined only by reference to the claims.

Claims

1. An air conditioning (AC) system, comprising: an indoor ventilation device, comprising a main blower which is used for receiving an outdoor air;at least one air-supply chain, each comprising “n” sub air-supply regions, each of the sub air-supply regions comprising at least one air inlet and at least one air outlet; andat least one cascading duct, each being used to one-by-one cascade each of the “n” sub air-supply regions by sequentially connecting with the at least one air inlet and/or the at least one air outlet of the “n” sub air-supply regions of each of the at least one air-supply chain, the at least one air inlet of one of the sub air-supply regions only connecting with one cascading duct of the at least one cascading duct and the at least one air outlet of the one of the sub air-supply regions only connecting with another cascading duct of the at least one cascading duct;wherein “n” is an integer and “n”1, air inlet of a first sub air-supply region of the “n” sub air-supply regions is connected with an air outlet of the main blower via the at least one cascading duct, an air inlet of a nth sub air-supply region of the “n” sub air-supply regions is connected with an air outlet of a (n−1)th sub air-supply region of the “n” sub air-supply regions, and an air outlet of the nth sub air-supply region of the “n” sub air-supply regions is connected with an exhausted air duct and return to the indoor ventilation device.

2. The AC system according to claim 1, wherein at least one of the at least one cascading duct is a partition wall connecting any two sub air-supply regions.

3. The AC system according to claim 1, wherein when “n” is larger than 2, except for the first sub air-supply region and the nth sub air-supply region of the “n” sub air-supply regions, the at least one air inlet of mth sub air-supply regions of the “n” sub air-supply regions is connected with the at least one air outlet of “(m−1)”th sub air-supply regions of the “n” sub air-supply regions and the at least one air outlet of the mth sub air-supply regions of the “n” sub air-supply regions is connected with the at least one air inlet of (m+1)th sub air-supply regions of the “n” sub air-supply regions, “m” is an integer and “n” is larger than “m”, “m” is larger than 1.

4. The AC system according to claim 1, further comprises a sub AC unit disposed inside of the each of the “n” sub air-supply regions.

5. The AC system according to claim 1, further comprises at least one sub blower disposed in at least one cascading duct.

6. A controlling method for an air conditioning (AC) system, comprising: transporting an outdoor air through a main blower of an indoor ventilation device to at least one air-supply chain;connecting sequentially at least one air inlet and/or at least one air outlet of “n” sub air-supply regions of the at least one air-supply chain through at least one cascading duct, and each of the “n” sub air-supply regions are cascaded one-by-one, wherein n is an integer and “n”>1;transporting the air sequentially to each of the “n” sub air-supply regions through the at least one cascading duct; andtransporting air back to the indoor ventilation device by connecting an exhausted duct with air outlet of the nth sub air-supply region;wherein the at least one air inlet of one of the sub air-supply regions is only connected with one cascading duct of the at least one cascading duct and the at least one air outlet of the one of the sub air-supply regions is only connected with another cascading duct of the at least one cascading duct.

7. The controlling method according to claim 6, comprising: disposing a sub AC unit inside each of the “n” sub air-supply regions to homogenize the air in the sub air-supply region.

8. The controlling method according to claim 6, wherein the indoor ventilation device is disposed outside the at least one air-supply chain.

9. The controlling method according to claim 6, wherein at least one of the at least one cascading duct is a partition wall connecting any two sub air-supply regions.

10. The controlling method according to claim 6, further comprises at least one sub blower disposed in at least one cascading duct.