Patent Description:
PATENT LITERATURE <NUM> discloses an air conditioning controller connected to an air conditioning apparatus via a network. The air conditioning controller predicts a temperature of a room in future after turning off the air conditioning apparatus, and causes the air conditioning apparatus to perform a preheating operation on the basis of the prediction in advance so that an indoor temperature reaches a target temperature at a time when the room is used next. In addition, a technique disclosed in Patent Literature <NUM> reduces a temperature difference between a set temperature and the indoor temperature to save energy by gradually increasing the set temperature of the air conditioning apparatus during the preheating operation.

PATENT LITERATURE <NUM>: <CIT>
<CIT> discloses features falling under the preamble of claim <NUM>. <CIT> and <CIT> are further prior art.

In the technique disclosed in PATENT LITERATURE <NUM>, the air conditioning apparatus is operated so that the indoor temperature is increased several tens of minutes to several hours before the time when the room is used next, and the indoor temperature reaches the target temperature exactly at the time when the room is used. However, in a case where the room is an office, if the air conditioning apparatus is turned off at night when work is finished and the indoor temperature is to reach the target temperature at the time when work is started the next morning, the air conditioning apparatus needs to be operated in a time zone when the outside temperature is low early morning, which causes poor energy efficiency.

An object of the present invention is to provide an air conditioning system, an air conditioning controller, an air conditioner, and an air conditioning control method that enable operation under better conditions in terms of energy efficiency and the like.

The invention is defined by the independent claims <NUM> and <NUM>.

In the air conditioning control method having the above configuration, by controlling the air conditioner in the first mode, the temperature of the target space is increased or decreased from a temperature closer to the target temperature than immediately before the second time to a temperature higher or lower than the target temperature, and thereafter, the temperature of the target space can be brought close to the target temperature by a natural temperature decrease or temperature rise. Therefore, an energy-efficient operation can be performed.

Embodiments of an air conditioning management system will be described in detail below with reference to the accompanying drawings.

<FIG> is a schematic configuration diagram of an air conditioning system according to Embodiment <NUM> of the present invention. <FIG> is a block diagram of the air conditioning system.

The air conditioning system includes an air conditioner <NUM> and a centralized management apparatus (air conditioning controller) <NUM>. The air conditioner <NUM> adjusts a temperature of air in a room, which is a target space for air conditioning, to a predetermined target temperature. The air conditioner <NUM> according to the present embodiment performs a heating operation for increasing at least an indoor temperature.

The air conditioner <NUM> includes an indoor unit <NUM> and an outdoor unit <NUM>. The air conditioner <NUM> according to the present embodiment is a multi-type air conditioner in which a plurality of indoor units <NUM> is connected in parallel to the outdoor unit <NUM>, and is applied to a building having multiple target spaces for air conditioning, for example. In an example illustrated in <FIG>, two indoor units <NUM> are connected to one outdoor unit <NUM>. However, the number of the outdoor units <NUM> and the number of the indoor units <NUM> are not limited.

The air conditioner <NUM> includes a refrigerant circuit <NUM>. The refrigerant circuit <NUM> circulates a refrigerant between the indoor units <NUM> and the outdoor unit <NUM>. The refrigerant circuit <NUM> includes a compressor <NUM>, a four-way switching valve <NUM>, an outdoor heat exchanger (heat source heat exchanger) <NUM>, an outdoor expansion valve <NUM>, a liquid shutoff valve <NUM>, indoor expansion valves <NUM>, indoor heat exchangers (utilization heat exchangers) <NUM>, a gas shutoff valve <NUM>, and refrigerant pipes <NUM> and <NUM> connecting these elements.

Each of the indoor units <NUM> includes an indoor expansion valve <NUM> and an indoor heat exchanger <NUM> included in the refrigerant circuit <NUM>. The indoor expansion valve <NUM> includes an electric expansion valve capable of adjusting a refrigerant flow rate. The indoor heat exchanger <NUM> is a cross fin tube type or microchannel type heat exchanger, and is used for exchanging heat with indoor air.

Each of the indoor units <NUM> further includes an indoor fan <NUM> and an indoor temperature sensor <NUM>. The indoor fan <NUM> is configured to take indoor air into the indoor unit <NUM>, cause the indoor heat exchanger <NUM> to exchange heat with the taken-in air, and then blow the air into the room. The indoor fan <NUM> includes a motor of which number of revolutions is adjustable by inverter control. The indoor temperature sensor <NUM> detects the indoor temperature.

The outdoor unit <NUM> includes the compressor <NUM>, the four-way switching valve <NUM>, the outdoor heat exchanger <NUM>, the outdoor expansion valve <NUM>, the liquid shutoff valve <NUM>, and the gas shutoff valve <NUM> that are included in the refrigerant circuit <NUM>.

The compressor <NUM> sucks a low-pressure gas refrigerant and discharges a high-pressure gas refrigerant. The compressor <NUM> includes a motor of which number of revolutions is adjustable by inverter control. The compressor <NUM> is of a variable capacity type (ability variable type) having capacity (ability) that is changeable by inverter control of the motor. Alternatively, the compressor <NUM> may be of a constant capacity type. A plurality of compressors <NUM> may be provided. In this case, compressors <NUM> of a variable capacity type and compressors <NUM> of a constant capacity type may coexist.

The four-way switching valve <NUM> reverses a refrigerant flow in the refrigerant pipe, and switches and supplies the refrigerant discharged from the compressor <NUM> to either the outdoor heat exchanger <NUM> or the indoor heat exchanger <NUM>. As a result, the air conditioner <NUM> can switch between a cooling operation and a heating operation. The air conditioner <NUM> according to the present embodiment only needs to be able to perform at least the heating operation, and the four-way switching valve <NUM> can be omitted when only the heating operation is performed.

The outdoor heat exchanger <NUM> is, for example, a cross fin tube type or microchannel type heat exchanger, and is used for exchanging heat with a refrigerant by using air as a heat source.

The outdoor expansion valve <NUM> includes an electric expansion valve capable of adjusting the refrigerant flow rate and the like.

The liquid shutoff valve <NUM> is a manual on-off valve. The gas shutoff valve <NUM> is also a manual on-off valve. The liquid shutoff valve <NUM> and the gas shutoff valve <NUM> are closed to block a refrigerant flow in the refrigerant pipes <NUM> and <NUM>, and are opened to allow a refrigerant flow in the refrigerant pipes <NUM> and <NUM>.

The outdoor unit <NUM> further includes an outdoor fan <NUM>, a suction pressure sensor <NUM>, a discharge pressure sensor <NUM>, a suction temperature sensor <NUM>, a discharge temperature sensor <NUM>, and the like. The outdoor fan <NUM> includes a motor of which number of revolutions is adjustable by inverter control. The outdoor fan <NUM> is configured to take outdoor air into the outdoor unit <NUM>, cause the outdoor heat exchanger <NUM> to exchange heat with the taken-in air, and then blow the air out of the outdoor unit <NUM>.

The suction pressure sensor <NUM> detects a pressure of the refrigerant sucked into the compressor <NUM>. The discharge pressure sensor <NUM> detects a pressure of the refrigerant discharged from the compressor <NUM>. The suction temperature sensor <NUM> detects a temperature of the refrigerant sucked into the compressor <NUM>. The discharge temperature sensor <NUM> detects a temperature of a refrigerant discharged from the compressor <NUM>. An evaporation pressure, a condensation pressure, a degree of superheating, and the like of the outdoor heat exchanger <NUM> and the indoor heat exchanger <NUM> are obtained by using detection values of the refrigerant pressure sensors <NUM> and <NUM> and the refrigerant temperature sensors <NUM> and <NUM>, and the number of revolutions of the compressor <NUM>, an opening degree of the outdoor expansion valve <NUM>, and the like are controlled so as to adjust these values.

During the cooling operation by the air conditioner <NUM> having the above configuration, the four-way switching valve <NUM> is held in a state indicated by solid lines in <FIG>. A high-temperature and high-pressure gaseous refrigerant discharged from the compressor <NUM> flows into the outdoor heat exchanger <NUM> through the four-way switching valve <NUM>, and exchanges heat with outdoor air by operation of the outdoor fan <NUM> to be condensed and liquefied. The liquefied refrigerant flows into each of the indoor units <NUM> through the outdoor expansion valve <NUM> in a fully open state. In each of the indoor units <NUM>, the refrigerant is decompressed to a predetermined low pressure by the indoor expansion valve <NUM>, and the refrigerant exchanges heat with indoor air in the indoor heat exchanger <NUM> to evaporate. The indoor air cooled by the evaporation of the refrigerant is blown into the room by the indoor fan <NUM> to cool the room. The refrigerant evaporated in the indoor heat exchanger <NUM> returns to the outdoor unit <NUM> through the gas refrigerant pipe <NUM>, passes through the four-way switching valve <NUM>, and is sucked into the compressor <NUM>. The air conditioner <NUM> operates in a similar manner to the cooling operation when performing a defrost operation of removing frost adhering to the outdoor heat exchanger <NUM>.

During the heating operation performed by the air conditioner <NUM>, the four-way switching valve <NUM> is held in a state indicated by broken lines in <FIG>. A high-temperature and high-pressure gaseous refrigerant discharged from the compressor <NUM> passes through the four-way switching valve <NUM>, and flows into the indoor heat exchanger <NUM> of each of the indoor units <NUM>. In the indoor heat exchanger <NUM>, the refrigerant exchanges heat with the indoor air to be condensed and liquefied. The indoor air heated by the condensation of the refrigerant is blown into the room by the indoor fan <NUM> to heat the room. The refrigerant liquefied in the indoor heat exchanger <NUM> returns to the outdoor unit <NUM> through the liquid refrigerant pipe <NUM>, is decompressed to a predetermined low pressure by the outdoor expansion valve <NUM>, and further exchanges heat with outdoor air in the outdoor heat exchanger <NUM> to evaporate. The refrigerant evaporated and vaporized by the outdoor heat exchanger <NUM> is sucked into the compressor <NUM> through the four-way switching valve <NUM>.

The indoor unit <NUM> further includes an indoor control unit <NUM>. The indoor control unit <NUM> includes a microcomputer and the like including a central processing unit (CPU) and a memory. Detection values of the sensors provided in the indoor unit <NUM> are input to the indoor control unit <NUM>. The indoor control unit <NUM> controls operations of the indoor expansion valve <NUM> and the indoor fan <NUM> on the basis of the detection values of the sensors and the like.

The outdoor unit <NUM> further includes an outdoor control unit <NUM>. The outdoor control unit <NUM> includes a microcomputer and the like including a CPU and a memory. Detection values of the sensors provided in the outdoor unit <NUM> are input to the outdoor control unit <NUM>. The outdoor control unit <NUM> controls operations of the outdoor expansion valve <NUM>, the compressor <NUM>, the outdoor fan <NUM>, and the like on the basis of detection values of the sensors and the like.

The indoor control unit <NUM> and the outdoor control unit <NUM> are communicably connected to each other via a transmission line. The indoor control unit <NUM> and the outdoor control unit <NUM> are connected to the centralized management apparatus <NUM> via a transmission line. The centralized management apparatus <NUM> includes a control unit 50a such as a microcomputer including a calculation unit such as a CPU and a storage such as a ROM and a RAM. The centralized management apparatus <NUM> is installed, for example, in a central management room of a building. The centralized management apparatus <NUM> manages the outdoor unit <NUM> and the indoor unit <NUM>. Specifically, the centralized management apparatus <NUM> monitors an operation status of the outdoor unit <NUM> and the indoor unit <NUM>, sets an air conditioning temperature, controls operation and stop, and the like by the control unit 50a.

The centralized management apparatus <NUM> according to the present embodiment executes a schedule operation as control of operation and stop of the air conditioner <NUM>. This schedule operation is an operation of starting the operation of the air conditioner <NUM> at a predetermined time (second time) and ending the operation of the air conditioner <NUM> at a predetermined time (first time). The first time and the second time are set as follows, for example. In a case where the air conditioning system is applied to an office building, the first time is set to a time between <NUM>:<NUM> and <NUM>:<NUM>, for example, in accordance with a closing time of a company that occupies the office building, and the second time is set to a time between <NUM>:<NUM> and <NUM>:<NUM>, for example, in accordance with an opening time of the company. Each of the first time and the second time is stored in the storage provided in the centralized management apparatus <NUM>.

The centralized management apparatus <NUM> according to the present embodiment executes "efficiency priority control" to cause the indoor temperature at the second time to efficiently reach a target temperature TM. Hereinafter, this efficiency execution control will be described in detail.

During a normal heating operation performed by the air conditioner <NUM>, the indoor control unit <NUM> obtains a required ability necessary for causing the indoor temperature to reach the target temperature (set temperature) on the basis of the temperature detected by the indoor temperature sensor <NUM>, the indoor target temperature, and the like, and controls the opening degree of the indoor expansion valve <NUM>, the number of revolutions of the indoor fan <NUM>, and the like. On the other hand, the outdoor control unit <NUM> controls the compressor <NUM> so as to satisfy the required ability obtained by the indoor control unit <NUM>. In this case, since it is prioritized to cause the indoor temperature to quickly reach the target temperature, the compressor <NUM> is operated at a large number of revolutions. Therefore, energy efficiency deteriorates, and energy consumption increases. In addition, a strong wind blown from the indoor fan <NUM> could increase noise or make a person hit by the strong wind uncomfortable. Therefore, an air volume of the indoor fan <NUM> is suppressed, and heating efficiency is lowered. As described above, the normal heating operation is not necessarily operated in an optimum state in terms of energy consumption and heating efficiency.

On the other hand, when there is no person in the room, for example, between the closing time (first time) and the starting time (second time) of a company, it is possible to efficiently operate the compressor <NUM> at a number of revolutions with a small energy consumption or operate the indoor fan <NUM> at a number of revolutions with a high heating efficiency, and it is possible to efficiently heat the room while reducing the energy consumption. Therefore, the centralized management apparatus <NUM> according to the present embodiment has a control mode for performing a preheating operation between the first time and the second time as one form of the "efficiency priority control".

<FIG> is a graph illustrating changes in an outdoor temperature Tout and an indoor temperature Tin after the air conditioner <NUM> is stopped at a predetermined time. A graph indicated by a thick solid line in <FIG> represents the indoor temperature Tin. In <FIG>, the air conditioner <NUM> is stopped at a first time te. A graph indicated by a thin solid line in <FIG> represents the outdoor temperature (outside temperature) Tout.

The outdoor temperature Tout gradually decreases at night (for example, from slightly before the first time te to the second time ts in <FIG>), and then turns to increase in the morning. On the other hand, the indoor temperature Tin is maintained at the predetermined target temperature TM by the air conditioner <NUM> until the first time te (for example, <NUM>:<NUM>), and at or after the first time te, indoor heat is released to the outside of the room from outer walls, windows, and the like of the building due to the stop of the air conditioner <NUM>, and gradually decreases. In the present embodiment, the centralized management apparatus <NUM> executes the efficiency priority control to adjust the indoor temperature Tin at a point of the second time ts to the target temperature TM. At this time, the compressor <NUM> is operated at a number of revolutions with a high energy efficiency, for example, a number of revolutions of about <NUM>% to <NUM>% of a maximum number of revolutions, and the indoor fan <NUM> is operated at a maximum number of revolutions. The indoor fans <NUM> of all the indoor units <NUM> are operated.

The centralized management apparatus <NUM> according to the present embodiment has two control modes of a "first mode" and a "second mode" as the efficiency priority control, and selects and executes one of the control modes on the basis of a predetermined condition.

In <FIG>, graphs indicated by (A) and (B) represent the indoor temperature Tin when control in the first mode is performed. The centralized management apparatus <NUM> stops the normal heating operation by the air conditioner <NUM> at the first time te by the schedule operation, and then starts the preheating operation by the air conditioner <NUM> before the second time ts. The control of the preheating operation in the first mode is control of operating the air conditioner <NUM> from the first time te to the second time ts, and stopping the air conditioner <NUM> when the indoor temperature increases to a predetermined temperature (preheating temperature) TH higher than the indoor target temperature TM at the second time ts. The preheating temperature TH is set such that the indoor temperature reaches the target temperature TM at the point of the second time ts by a decrease of the indoor temperature after the air conditioner <NUM> is stopped.

In the graph of (B), as a representative, ta, tb, TL, and TH are assigned to a preheating start time, a preheating end time, the indoor temperature at a time of starting the preheating, and the indoor temperature at a time of ending the preheating, respectively.

Immediately after the air conditioner <NUM> performs the heating operation until the first time te, the outdoor temperature Tout is higher than the second time ts. Therefore, there is a possibility that the air conditioner <NUM> can perform the heating operation with higher energy efficiency immediately after the first time te than immediately before the second time ts. In a case where heat insulation performance of the building is high, the indoor temperature is less likely to decrease. It is therefore not necessary to set the preheating temperature TH so high, and the energy consumption is more likely to be suppressed.

In <FIG>, a graph indicated by (C) represents the indoor temperature Tin in a case where control in the second mode is performed. The control of the preheating operation in the second mode is control to start the operation of the air conditioner <NUM> at or after the first time te and increase the indoor temperature to the target temperature TM at the point of the second time ts. Therefore, unlike the preheating operation in the first mode, the preheating operation in the second mode does not increase the indoor temperature until the temperature exceeds the target temperature TM.

The centralized management apparatus <NUM> selects and executes the first mode and the second mode on the basis of any of the following conditions.

The energy consumption by the air conditioner <NUM> can be obtained as follows.

As illustrated in <FIG>, in a case where the preheating operation is performed by the air conditioner <NUM>, energy consumption (electric power) P (J (= Ws)) can be expressed by the following equation (<NUM>). <NUM>] <MAT>.

In equation (<NUM>), COPave is an average value of coefficient of performance (COP) which is energy consumption efficiency (coefficient of performance) from the preheating start time ta to the preheating end time tb. Qa (J) is an amount of heat necessary to raise the indoor temperature from TL to TH, and can be expressed by the following equation (<NUM>). <NUM>] <MAT>.

Note that C (J/K) is a heat capacity of air or a building in the target space.

In equation (<NUM>), Qe (J) is a heat loss amount of the building from the time ta at which the preheating operation is started to the second time ts, and can be expressed by the following equation (<NUM>). <NUM>] <MAT>.

Note that η (W/K (= (J/s)/K)) is a heat loss coefficient of the building, and ΔT (K (or °C)) is a difference between the indoor temperature Tin and the outdoor temperature Tout.

In equation (<NUM>), the outdoor temperature Tout is a predicted value estimated at a point of the first time te. For example, as the outdoor temperature Tout, an average value or the like during the past several days is adopted. The outdoor temperature Tout may be obtained by machine learning using various factors related to the past outdoor temperature and outdoor temperature as inputs. The outdoor temperature Tout may be forecast information provided from a business operator such as a meteorological observatory. In either case, outdoor temperature information is stored in the storage of the centralized management apparatus <NUM> and used for calculation of the electric power and the like. The indoor temperature Tin is also a predicted value assumed at the point of the first time te. The indoor temperature Tin is estimated from the value of the outdoor temperature Tout in consideration of factors such as a structure, heat insulation performance, and floor area of the building, and is stored in the storage of the centralized management apparatus <NUM>.

The centralized management apparatus <NUM> according to the present embodiment calculates values of P at a plurality of points between the first time te and the second time ts. Then, as illustrated in <FIG>, a relationship between the preheating operation start time and the energy consumption (electric power) P is obtained. In a case where Condition <NUM> is adopted, the centralized management apparatus <NUM> selects the control mode with the lowest energy consumption and a start time of the control mode. In the example illustrated in <FIG>, the energy consumption is the smallest in (B) of the first mode. Therefore, in a case where Condition <NUM> is adopted, the centralized management apparatus <NUM> starts the control in the first mode at the time ta.

On the other hand, in a case where Condition <NUM> is adopted, the centralized management apparatus <NUM> further multiplies the energy consumption (electric power) P by a charge per unit electric power (unit price) to obtain the electricity charge. The centralized management apparatus <NUM> selects the control mode with the lowest electricity charge and the start time of the control mode. Accordingly, it is possible to execute efficiency suppression control in which the electricity charge is suppressed. Since charge per unit electric power may be reduced depending on a time zone such as late at night, in a case where Condition <NUM> is adopted, the preheating operation advantageous in terms of not only a magnitude of the electric power P but also cost can be executed.

The heat insulation performance of the building to which the air conditioning system is applied has a great influence on a change in the indoor temperature Tin. For example, when the heat insulation performance of the building is high, a decrease in the indoor temperature becomes moderate even after the operation of the air conditioner <NUM> is stopped, and the indoor temperature can be increased in a short time. Therefore, in the present embodiment, by including the heat loss amount Qe in equation (<NUM>), the energy consumption can be obtained in consideration of a heat loss of the building from the preheating operation start time ta to the second time ts.

The COP indicating the energy consumption efficiency (coefficient of performance) of the air conditioner <NUM> is obtained from a heating ability (heating heat amount) and power consumption, and changes in accordance with the outdoor temperature Tout. The COP, which varies depending on device characteristics, can be obtained from the power consumption and the heating ability with reference to ISO <NUM>-<NUM>. On the other hand, in a case where the heating operation is performed by the air conditioner <NUM>, when the outdoor temperature Tout is in a predetermined temperature range, for example, from <NUM> to -<NUM>, the defrost operation of reversing the refrigerant flow in the refrigerant circuit is periodically performed, and frost adhering to the outdoor unit <NUM> is removed. During the defrost operation, the room is not heated, and electric power is consumed to melt frost, and thus the COP decreases. Therefore, when the preheating operation is performed in the temperature range in which the defrost operation occurs, the energy consumption increases. In the present embodiment, a value in consideration of the defrost operation is also adopted as COPave (see equation (<NUM>)) used for obtaining the energy consumption, and thus the preheating operation can be performed at a more appropriate timing.

<FIG> is a flowchart of processing of determining a control mode in the efficiency priority control. In order to perform the efficiency priority control, the centralized management apparatus <NUM> determines whether the time has reached the first time te as illustrated in step S1 in <FIG>. When determining that the time has reached the first time te, the centralized management apparatus <NUM> calculates an energy consumption (Condition <NUM>) or an electricity charge (Condition <NUM>) in a case where the efficiency priority control is performed at a plurality of points between the first time te and the second time ts (step S2).

The centralized management apparatus <NUM> determines which of the first mode or the second mode is advantageous in terms of energy consumption or electricity charge (step S3), and selects and executes a more advantageous control mode (steps S4 and S5). As described above, the air conditioner <NUM> performs appropriate preheating operation, and the indoor temperature can reach the target temperature TM at the point of the second time ts.

The centralized management apparatus <NUM> according to Embodiment <NUM> has a control mode for performing a "precooling operation" between the first time and the second time as one form of "efficiency priority control". The air conditioner <NUM> according to the present embodiment performs the cooling operation for decreasing at least the indoor temperature.

<FIG> is a graph illustrating changes in the outdoor temperature Tout and the indoor temperature Tin after the air conditioner <NUM> is stopped at a predetermined time in an air conditioning system according to Embodiment <NUM>. A graph indicated by a thick solid line in <FIG> represents the indoor temperature Tin. In <FIG>, the air conditioner <NUM> is stopped at the first time te. A graph indicated by a thin solid line in <FIG> represents the outdoor temperature (outside temperature) Tout.

In summer and the like, the outdoor temperature Tout gradually increases, for example, from early morning to daytime (for example, from slightly before the first time te to the second time ts in <FIG>). On the other hand, the indoor temperature Tin is maintained at the predetermined target temperature TM by the air conditioner <NUM> until the first time (for example, <NUM>:<NUM> am) te, and at or after the first time te, outdoor heat enters the room from outer walls, windows, and the like of the building due to the stop of the air conditioner <NUM>, and gradually increases. In the present embodiment, the centralized management apparatus <NUM> executes the efficiency priority control to adjust the indoor temperature Tin at the point of the second time (for example, <NUM>:<NUM> pm) ts to the target temperature TM. At this time, the compressor <NUM> is operated at a number of revolutions with a high energy efficiency, for example, a number of revolutions of about <NUM>% to <NUM>% of a maximum number of revolutions, and the indoor fan <NUM> is operated at a maximum number of revolutions. The indoor fans <NUM> of all the indoor units <NUM> are operated.

In <FIG>, graphs indicated by (A) and (B) represent the indoor temperature Tin when control in the first mode is performed. The centralized management apparatus <NUM> stops the normal cooling operation by the air conditioner <NUM> at the first time te by the schedule operation, and then starts the precooling operation by the air conditioner <NUM> before the second time ts. The control of the precooling operation in the first mode is control of operating the air conditioner <NUM> from the first time te to the second time ts, and stopping the air conditioner <NUM> when the indoor temperature decreases to a predetermined temperature (precooling temperature) TL lower than the indoor target temperature TM at the second time ts. The precooling temperature TL is set such that the indoor temperature reaches the target temperature TM at the point of the second time ts by an increase of the indoor temperature after the air conditioner <NUM> is stopped.

In the graph of (B), as a representative, ta, tb, TH, and TL are assigned to a precooling start time, a precooling end time, the indoor temperature at a time of starting the precooling, and the indoor temperature at a time of ending the precooling, respectively.

Immediately after the air conditioner <NUM> performs the cooling operation until the first time te, the indoor temperature Tin is closer to the target temperature TM than immediately before the second time ts. Therefore, there is a possibility that the air conditioner <NUM> can perform the cooling operation with higher energy efficiency immediately after the first time te than immediately before the second time ts. However, immediately after the air conditioner <NUM> performs the cooling operation until the first time te, the outdoor temperature Tout is lower than the second time ts. Therefore, there is a possibility that the air conditioner <NUM> can perform the cooling operation with higher energy efficiency immediately after the first time te than immediately before the second time ts. In a case where heat insulation performance of the building is high, the indoor temperature is less likely to increase. It is therefore not necessary to set the precooling temperature TL so low, and the energy consumption is more likely to be suppressed.

In <FIG>, a graph indicated by (C) represents the indoor temperature Tin in a case where control in the second mode is performed. The control of the precooling operation in the second mode is control of starting the operation of the air conditioner <NUM> at or after the first time te and decreasing the indoor temperature to the target temperature TM at the point of the second time ts. Therefore, unlike the precooling operation in the first mode, the precooling operation in the second mode does not decrease the indoor temperature until the temperature becomes lower than the target temperature TM.

As in the case of Embodiment <NUM>, the centralized management apparatus <NUM> according to the present embodiment selects and executes either the first mode or the second mode on condition that the energy consumption is lower or the electricity charge is lower. The energy consumption and the electricity charge by the air conditioner <NUM> can be calculated by replacing the calculation method in Embodiment <NUM> with the cooling operation (precooling operation). The centralized management apparatus <NUM> according to the present embodiment can perform processing of determining selection of a control mode in accordance with a procedure illustrated in the flowchart of <FIG>.

The second mode in the efficiency priority control described above is control of increasing or decreasing the indoor temperature to the target temperature TM at the point of the second time ts. However, the second mode may be control of starting the operation at the second time ts. In this case, since the preheating operation and the precooling operation are performed only in the first mode, the efficiency priority control by the centralized management apparatus <NUM> is selected between the preheating operation or the precooling operation in the first mode and the normal operation in the second mode, and an operation with lower energy consumption or lower electricity charge is selected.

The first time te described above is a time when the air conditioner <NUM> stops due to the schedule operation. However, any of the following times may be adopted as the first time te.

In a case where the efficiency priority control is performed at the time of (a) or (b), the temperature of the target space is not required to reach the target temperature TM quickly, and there is no need to consider a possibility of making a person uncomfortable. It is therefore possible to perform an operation with low energy consumption and high heating efficiency or high cooling efficiency.

In a case where (a) or (b) is adopted as the first time te, for example, the following means can be adopted in order to determine whether the time has reached the first time te.

The detection of (I) can be performed by installing a human sensor in the target space. Alternatively, a camera is installed in the target space, and presence or absence of a person can be determined by processing a captured image.

The detection of (II) can be performed by, for example, detecting, by a sensor, that illumination of the target space is turned off and receiving a detection signal of the sensor by the centralized management apparatus <NUM>.

The detection of (III) can be performed by, for example, detecting, by a sensor, that the target space or the building is locked and receiving a detection signal of the sensor by the centralized management apparatus <NUM>.

In Embodiment <NUM>, the preheating temperature TH is set such that the temperature of the target space at the second time ts becomes the target temperature TM in the first mode of the efficiency priority control. However, in the air conditioning system of the present invention, since it is sufficient to achieve a situation in which the target space is heated at the second time ts with higher efficiency than in a case where the target space is heated by operating the air conditioner <NUM> at a time close to the second time ts, the preheating temperature TH may be set such that the temperature of the target space at the second time ts becomes higher than the target temperature TM. In a similar manner, in Embodiment <NUM>, the precooling temperature TL is set such that the temperature of the target space at the second time ts becomes the target temperature TM in the first mode of the efficiency priority control. However, in the air conditioning system of the present invention, since it is sufficient to achieve a situation in which the target space is cooled at the second time ts with higher efficiency than in a case where the target space is cooled by operating the air conditioner <NUM> at a time close to the second time ts, the precooling temperature TL may be set such that the temperature of the target space at the second time ts becomes lower than the target temperature TM.

<FIG> is a schematic configuration diagram of an air conditioning system according to another embodiment.

The air conditioning system illustrated in <FIG> includes a management server <NUM>. The management server <NUM> is provided at a remote location away from the building in which the air conditioner <NUM> is installed. The management server <NUM> includes, for example, a personal computer including a control unit 55a having a calculation unit such as a CPU and a storage such as a ROM and a RAM. The centralized management apparatus <NUM> and the management server <NUM> are communicably connected via a network <NUM> such as the Internet.

In a case where the air conditioning system includes the management server <NUM> as in the example illustrated in <FIG>, instead of the centralized management apparatus <NUM>, the management server <NUM> may execute the efficiency priority control. In a case where the air conditioning system does not include the centralized management apparatus <NUM>, the outdoor control unit <NUM> and the indoor control unit <NUM> may be connected to the management server <NUM> via the network <NUM>.

In a case where the air conditioning system does not include the centralized management apparatus <NUM> and the management server <NUM>, the indoor control unit <NUM> and/or the outdoor control unit <NUM> of the air conditioner <NUM> may execute the efficiency priority control. In this case, the indoor control unit <NUM> and/or the outdoor control unit <NUM> of the air conditioner <NUM> constitute a control unit that executes the efficiency priority control.

The centralized management apparatus <NUM>, the management server <NUM>, the outdoor control unit <NUM>, or the indoor control unit <NUM> may be configured to be able to execute both the preheating operation and the precooling operation instead of either the preheating operation or the precooling operation as the first mode of the efficiency priority control. In this case, for example, when the air conditioner <NUM> performs the heating operation in wintertime, the centralized management apparatus <NUM> and the like can perform the preheating operation as the first mode, and when the air conditioner <NUM> performs the cooling operation in summertime, for example, the precooling operation can be performed as the first mode.

In general, the air conditioner <NUM> used in an office or the like performs a schedule operation so as to be operated in a time zone in which the target space is used and to be stopped in a time zone in which the target space is not used. The temperature of the target space gradually decreases or increases from the target temperature (set temperature) TM of the target space between an end of use of the target space and the next use of the target space. Therefore, the temperature of the target space is closer to the target temperature TM immediately after the end of use of the target space than immediately before the next use of the target space, and it is advantageous in terms of energy efficiency to operate the air conditioner <NUM> at that point of time. In the air conditioning system according to the present embodiment, by controlling the air conditioner <NUM> in the first mode, the temperature of the target space is increased or decreased from a temperature closer to the target temperature TM than immediately before the second time ts, and thereafter, the temperature of the target space can be brought close to the target temperature TM by a natural temperature decrease or temperature rise. Therefore, an energy-efficient operation can be performed.

(<NUM>) In the above embodiment, the air conditioning controller <NUM> or <NUM> has the second mode as a control mode together with the first mode. In a case where the first mode is a control mode in which the air conditioner <NUM> performs the preheating operation, the second mode is a control mode in which the air conditioner <NUM> is operated from a temperature lower than the target temperature TM of the second time ts to increase the temperature of the target space to the target temperature TM. In a case where the first mode is a control mode in which the air conditioner <NUM> performs the precooling operation, the second mode is a control mode in which the air conditioner <NUM> is operated from a temperature higher than the target temperature TM of the second time ts to decrease the temperature of the target space to the target temperature TM. The air conditioning controller <NUM> or <NUM> selects and executes either the first mode or the second mode on the basis of a predetermined determination criterion. It is therefore possible to operate the air conditioner <NUM> in a more appropriate control mode in accordance with the predetermined determination criterion.

(<NUM>) In the above embodiment, the second mode is a control mode of causing the temperature of the target space to reach the target temperature TM at the second time ts. Alternatively, the second mode can be a control mode in which the air conditioner <NUM> is operated from the second time ts to cause the temperature of the target space to reach the target temperature TM. In this case, it is possible to determine which of the preheating operation and precooling operation or the normal heating operation or cooling operation is advantageous in terms of the energy consumption or the electricity charge, and to adopt either of the operations.

(<NUM>) In the above embodiment, the air conditioning controller <NUM> or <NUM> executes a control mode of the first mode or the second mode with a lower energy consumption. Therefore, an efficient operation in terms of energy can be performed.

(<NUM>) In the above embodiment, the air conditioning controller <NUM> or <NUM> executes a control mode of the first mode or the second mode with a lower electricity charge. Therefore, an efficient operation in terms of cost can be performed.

(<NUM>) In the above embodiment, the air conditioning controller <NUM> or <NUM> executes the first mode or the second mode on the basis of an energy consumption obtained in consideration of heat insulation performance in the target space. Since the heat insulation performance of the target space affects the energy consumption, a more appropriate control mode can be executed by considering the heat insulation performance of the target space in obtaining the energy consumption.

(<NUM>) In the above embodiment, the air conditioning controller <NUM> or <NUM> executes the first mode or the second mode on the basis of an energy consumption obtained in consideration of a predicted value of an outside temperature at or after the first time te. Since the outside temperature affects the energy consumption, a more appropriate control mode can be executed by considering the predicted value of the outside temperature in obtaining the energy consumption.

(<NUM>) In the above embodiment, the air conditioning controller <NUM> or <NUM> executes the first mode or the second mode on the basis of an energy consumption obtained in consideration of a predicted value of a difference between the temperature of the target space and the outside temperature at or after the first time te. Since the difference between the temperature of the target space and the outside temperature affects the energy consumption, a more appropriate control mode can be executed by considering the predicted value of the difference between the temperature of the target space and the outside temperature in obtaining the energy consumption.

(<NUM>) In the above embodiment, the air conditioning controller <NUM> or <NUM> executes the first mode and the second mode on the basis of an energy consumption obtained in consideration of necessity of a defrost operation in accordance with a predicted value of the outside temperature. In a case where the outside temperature is in a predetermined temperature range, since the energy consumption is increased by operating the air conditioner <NUM> in the defrost operation, a more appropriate control mode can be executed by considering necessity of the defrost operation in obtaining the energy consumption.

(<NUM>) In the above embodiment, the first time te is a time at which the air conditioner <NUM> is stopped in the schedule operation, a time at which the target space is not in use any more, or a time at which no person appears in the target space. In any case, there is a high possibility that no person is in the target space, and it is therefore possible to perform driving with priority given to efficiency.

(<NUM>) The air conditioner <NUM> according to another embodiment described above includes a control unit (indoor control unit <NUM> and/or outdoor control unit <NUM>) having, as a control mode, a first mode in which the air conditioner <NUM> is operated in the preheating operation or the precooling operation at or after the first time te set in advance and at or before the second time ts at which the target space is used next, in which the first mode is control in which the air conditioner <NUM> is operated and the air conditioner <NUM> is stopped when the temperature of the target space increases to the preheating temperature TH higher than the target temperature TM of the target space at the second time ts or when the temperature of the target space decreases to the precooling temperature TL lower than the target temperature TM. The preheating temperature TH is set such that the temperature of the target space becomes the target temperature TM or a temperature higher than the target temperature TM at the point of the second time ts due to a decrease of the temperature of the target space after the air conditioner <NUM> is stopped in the first mode. The precooling temperature TL is set such that the temperature of the target space becomes the target temperature TM or a temperature lower than the target temperature TM at the point of the second time ts by an increase of the temperature of the target space after the air conditioner <NUM> is stopped in the first mode.

In the air conditioner <NUM> having the above configuration, by controlling the air conditioner in the first mode by the control unit, the temperature of the target space is increased or decreased from a temperature closer to the target temperature TM than immediately before the second time ts, and thereafter, the temperature of the target space can be brought close to the target temperature TM by a natural temperature decrease or temperature rise. Therefore, an energy-efficient operation can be performed.

(<NUM>) The air conditioning control method according to the above embodiment is an air conditioning control method of controlling the air conditioner <NUM> that adjusts the temperature of the target space, the air conditioning control method including operating the air conditioner <NUM> in a first step at or after a first time set in advance and at or before a second time ts at which the target space is used next, and stopping the air conditioner <NUM> in a second step when the temperature of the target space increases to a preheating temperature TH higher than a target temperature of the target space at the second time or decreases to a precooling temperature TL lower than the target temperature. The preheating temperature TH is set such that the temperature of the target space becomes the target temperature TM or a temperature higher than the target temperature TM at the point of the second time ts due to a decrease of the temperature of the target space after the air conditioner <NUM> is stopped in the second step. The precooling temperature TL is set such that the temperature of the target space becomes the target temperature TM or a temperature lower than the target temperature TM at the point of the second time ts due to an increase of the temperature of the target space after the air conditioner <NUM> is stopped in the second step.

Claim 1:
An air conditioning controller that controls an air conditioner (<NUM>) that adjusts a temperature of a target space, wherein
the air conditioning controller has, as a control mode, a first mode in which the air conditioner (<NUM>) performs a preheating operation or a precooling operation at or after a first time (te) set in advance and at or before a second time (ts) at which the target space is used next,
the first mode is control of operating the air conditioner (<NUM>) and stopping the air conditioner (<NUM>) when the temperature of the target space increases to a preheating temperature (TH) higher than a target temperature (TM) of the target space at the second time (ts) or when the temperature of the target space decreases to a precooling temperature (TL) lower than the target temperature (TM),
the preheating temperature (TH) is set such that the temperature of the target space becomes the target temperature (TM) or higher than the target temperature (TM) at a point of the second time (ts) due to a decrease of the temperature of the target space after the air conditioner (<NUM>) stops in the first mode, and
the precooling temperature (TL) is set such that the temperature of the target space becomes the target temperature (TM) or lower than the target temperature (TM) at the point of the second time (ts) due to an increase of the temperature of the target space after the air conditioner (<NUM>) stops in the first mode, wherein
the air conditioning controller (<NUM>, <NUM>) has a second mode as a control mode together with the first mode,
in a case where the first mode is a control mode in which the air conditioner (<NUM>) performs the preheating operation, the second mode is a control mode in which the air conditioner (<NUM>) is operated from a temperature lower than the target temperature (TM) at the second time (ts) to increase the temperature of the target space to the target temperature (TM),
in a case where the first mode is a control mode in which the air conditioner (<NUM>) performs the precooling operation, the second mode is a control mode in which the air conditioner (<NUM>) is operated from a temperature higher than the target temperature (TM) at the second time (ts) to decrease the temperature of the target space to the target temperature (TM), and
the air conditioning controller (<NUM>, <NUM>) selects and executes either the first mode or the second mode based on a predetermined determination criterion.