Air conditioning device

Abstract

To disclose one example of power failure start-up control for a compressor focusing on a server room temperature change during power failure, in an air conditioner in which a drive frequency is controlled so that a suction temperature T2 becomes a setting temperature.SOLUTION: An acceleration of a drive frequency and an upper limit drive frequency fmax are determined using a temperature difference ΔT and a power failure time Ts, and the drive frequency is increased to the upper limit drive frequency fmax using the determined acceleration. The temperature difference ΔT is the difference between an estimated suction temperature T4 and an air conditioner-side temperature T5 at the time when the air conditioner is stopped. The estimated suction temperature T4 is a temperature estimated by a temperature estimation unit 6B as the suction temperature at the time when power supply is restored after power failure. The air conditioner side temperature T5 at the time when the air conditioner is stopped is a server room temperature T1 detected when the power supply is stopped.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an air conditioner that utilizes a refrigerator having an electric compressor. [Background technology]

[0002] For example, in the air conditioner described in Patent Document 1, the temperature difference between a first air conditioner and a second air conditioner is compared to determine control for starting up the two air conditioners. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6578920 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, an air conditioning unit that cools a so-called server room in which information and communication technology equipment (hereinafter referred to as ICT equipment) is installed is equipped with a heat exchanger that cools the air drawn in from the server room and supplies it to the server room, and maintains the temperature inside the server room within a specified temperature range by adjusting the refrigeration capacity generated by the heat exchanger.

[0005] The refrigeration capacity is adjusted by controlling the rotation speed of the compressor, i.e., the frequency of the drive current when driving the electric compressor. The drive control unit of the compressor controls the drive frequency so that the air temperature before heat exchange in the heat exchanger or the air temperature after heat exchange in the heat exchanger (hereinafter, these temperatures are referred to as air conditioner side temperatures) becomes a preset temperature.

[0006] The present disclosure discloses an example of compressor startup control during a power outage, focusing on temperature changes in the space to be air-conditioned during a power outage, in an air conditioning device in which the drive frequency is controlled so that the air conditioner side temperature becomes a preset temperature. [Means for solving the problem]

[0007] An air conditioner utilizing a refrigerator (1) having an electric compressor (2) desirably has at least one of the following components, for example.

[0008] That is, the components include a heat exchanger (5) that cools or heats air drawn from a space to be air-conditioned and supplies the air to the space to be air-conditioned, a room temperature sensor (S1) that detects the air temperature in the space to be air-conditioned, the room temperature sensor (S1) being supplied with power from an uninterruptible power supply at least during a power outage, an air conditioning temperature sensor (S2) that detects the air temperature before heat exchange in the heat exchanger (5) or the air temperature after heat exchange in the heat exchanger (5) (hereinafter, these temperatures will be referred to as air conditioner side temperatures), and a drive current that controls the frequency (hereinafter, referred to as drive frequency) of a drive current that drives a compressor (2). The dynamic control unit (6A) includes a drive control unit (6A) capable of controlling the drive frequency at least by power failure startup control or normal control, and a temperature estimation unit (6B) that estimates an air conditioner side temperature from the detected temperature of the room temperature sensor (S1) by utilizing a difference between the detected temperature of the room temperature sensor (S1) and the detected temperature of the air conditioning temperature sensor (S2) when the compressor (2) is operating under normal control, and the drive control unit (6A) determines at least an acceleration of the drive frequency by utilizing the temperature difference (ΔT) and the power failure time (Ts), and the power failure startup control is a control that increases and changes the drive frequency at the determined acceleration.

[0009] The power failure startup control is executed when the power supply is restored after the power supply is stopped, and the normal control is executed after the power failure startup control is completed, and adjusts the drive frequency so that the detected temperature of the air conditioning temperature sensor (S2) becomes a preset temperature.

[0010] In addition, the temperature estimated by the temperature estimation unit (6B) as the air conditioner side temperature when power supply is restored is defined as the estimated air conditioner side temperature, the temperature detected by the air conditioning temperature sensor (S2) when power supply is stopped is defined as the air conditioner side temperature when stopped, the difference between the estimated air conditioner side temperature and the air conditioner side temperature when stopped is defined as the temperature difference (ΔT), and the time from when power supply is stopped to when power supply is restored is defined as the power outage duration (Ts).

[0011] As a result, according to the air conditioner, the compressor (2) can be started up quickly after power is restored, and as a result, even in the event of a power outage, a large change in the air temperature in the space to be air conditioned can be suppressed.

[0012] Incidentally, the symbols in the above parentheses are examples showing the corresponding relationship with the specific configurations etc. described in the embodiments described below, and the present disclosure is not limited to the specific configurations etc. shown by the symbols in the above parentheses. [Brief description of the drawings]

[0013] [Figure 1] 1 is a diagram showing an air conditioner according to a first embodiment. [Diagram 2] 4 is a table showing start-up patterns of start-up control during a power failure according to the first embodiment. [Diagram 3] 13 is a graph showing changes in temperature in a server room. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The following "embodiment of the invention" shows an example of an embodiment that falls within the technical scope of the present disclosure. In other words, the invention-specific matters described in the claims are not limited to the specific configurations and structures shown in the following embodiment.

[0015] At least one of each of the components or parts described with a reference symbol is provided, unless otherwise specified by "one". In other words, unless otherwise specified by "one", two or more of the components may be provided. The air conditioner disclosed in this disclosure includes at least the components or parts described with a reference symbol, as well as the structural parts shown in the drawings.

[0016] (First embodiment) <1. Air conditioner configuration> In this embodiment, the present disclosure is applied to an air conditioning device that conditions air in a communication equipment room, a server room, etc. (hereinafter, referred to as a server room.) In other words, the air conditioning device according to this embodiment treats the server room as a space to be air-conditioned and adjusts the temperature, etc. of the space to be air-conditioned.

[0017] At least one piece of information and communication technology equipment (hereinafter referred to as ICT equipment) is installed in the server room. The ICT equipment is supplied with power via an uninterruptible power supply (hereinafter referred to as UPS).

[0018] The refrigerator 1 shown in Fig. 1 generates cold heat for air conditioning the inside of a server room. The refrigerator 1 is configured as a vapor compression refrigerator having an electric compressor 2. Specifically, the refrigerator 1 has the compressor 2, a radiator 3, a pressure reducer 4, an evaporator 5, a control device 6, a room temperature sensor S1, a suction temperature sensor S2, a blowing temperature sensor S3, and the like.

[0019] The compressor 2 compresses the low-pressure gas-phase refrigerant flowing out from the evaporator 5. The radiator 3 cools the high-pressure refrigerant discharged from the compressor 2 and having an increased temperature. In the radiator 3 according to this embodiment, the cooled refrigerant is condensed (liquefied).

[0020] The pressure reducer 4 reduces the pressure of the refrigerant flowing out from the radiator 3. The pressure reducer 4 according to this embodiment is configured with a thermostatic expansion valve. The thermostatic expansion valve automatically adjusts the opening degree (degree of pressure reduction) so that the degree of superheat of the refrigerant at the outlet side of the evaporator 5 becomes a predetermined value.

[0021] The evaporator 5 generates refrigeration capacity, that is, cold heat, by evaporating the liquid-phase refrigerant decompressed by the pressure reducer 4. Specifically, the evaporator 5 exchanges heat between the refrigerant and the air-conditioning air supplied to the server room, thereby cooling the air-conditioning air.

[0022] The air conditioner includes a fan 5A in addition to the refrigerator 1. The fan 5A draws in air from within the server room and blows the air to the evaporator 5, and supplies the air cooled by the evaporator 5 to the server room.

[0023] The control device 6 controls components of the air conditioner such as the compressor 2 and the blower 5A. The control device 6 receives detection values ​​of the room temperature sensor S1, the suction temperature sensor S2, and the discharge temperature sensor S3.

[0024] The room temperature sensor S1 detects the air temperature inside the server room (hereinafter referred to as server room temperature T1). The room temperature sensor S1 according to this embodiment detects the air temperature before it is heated by a heating element arranged inside the server room, that is, the air temperature before it is heated by ICT equipment.

[0025] Specifically, the interior of the server room according to this embodiment is separated into a cold aisle (a space for supplying cold air) and a hot aisle (a space for exhausting hot air). The room temperature sensor S1 detects the air temperature in the cold aisle.

[0026] The cold aisle is a space for distributing and supplying the cold air supplied from the evaporator 5 to each piece of ICT equipment. The hot aisle is a space where the air whose temperature has increased after cooling each piece of ICT equipment gathers. The blower 5A draws in the air in the hot aisle and supplies it to the evaporator 5.

[0027] The suction temperature sensor S2 detects the air temperature (hereinafter referred to as suction temperature T2) before heat exchange in the evaporator 5. The blow-out temperature sensor S3 detects the air temperature after heat exchange in the evaporator 5 (hereinafter referred to as blow-out temperature T3).

[0028] The room temperature sensor S1 is supplied with power via a UPS. The suction temperature sensor S2 and the discharge temperature sensor S3 are supplied with power from a power source (not shown) of the air conditioner. Therefore, in the event of a power outage, the suction temperature sensor S2 and the discharge temperature sensor S3 stop functioning.

[0029] Incidentally, the air conditioner according to this embodiment is equipped with an engine-driven power supply device (not shown) as a power supply device for use during a power outage (emergency use). When the power supply from the commercial power source is stopped, the engine automatically starts and power is supplied to the air conditioner.

[0030] <2. Control operation of the control device> The control device 6 has at least a drive control unit 6A and a temperature estimation unit 6B. The control device 6 according to this embodiment is configured with a microcomputer having a CPU, a ROM, a RAM, etc. The drive control unit 6A and the temperature estimation unit 6B are realized by the CPU executing software prestored in a non-volatile storage unit (not shown) such as a ROM.

[0031] <2.1 Drive control unit> The drive control unit 6A controls the operation of the compressor 2 via an inverter type drive circuit (not shown). Specifically, the drive control unit 6A controls the frequency of a drive current (hereinafter referred to as a drive frequency). The drive current is a current that drives the compressor 2.

[0032] The drive control unit 6A (hereinafter, referred to as the control device 6) can control the drive frequency at least by power failure startup control or normal control. Power failure startup control is a control that is executed when the power supply to the air conditioner is restored after the power supply is stopped. Details of the power failure startup control will be described later.

[0033] Normal control is executed after the power outage startup control ends and when power is being supplied normally, and adjusts the drive frequency so that the detected temperature of the suction temperature sensor S2, i.e., the suction temperature T2, becomes a predetermined temperature (hereinafter referred to as the set temperature).

[0034] Specifically, when the suction temperature T2 is higher than the set temperature, the control device 6 increases the drive frequency. When the suction temperature T2 is lower than the set temperature, the control device 6 decreases the drive frequency. This keeps the suction temperature T2 at the set temperature.

[0035] The control device 6 according to the present embodiment controls the airflow rate of the blower 5A so that the "temperature difference between the blowing temperature T3 and the set temperature" or the "temperature difference between the blowing temperature T3 and the suction temperature T2" ​​becomes a predetermined temperature difference. In other words, the control device 6 controls the blower 5A so that the blowing temperature T3 becomes a predetermined temperature.

[0036] <2.2 Temperature estimation part> The temperature estimation unit 6B uses the detected temperature (server room temperature T1) of the room temperature sensor S1 to estimate the air temperature before heat exchange in the evaporator 5. That is, the temperature estimation unit 6B estimates the temperature using the difference between the server room temperature T1 and the suction temperature T2 when the compressor 2 is operating under normal control.

[0037] Specifically, temperature estimation unit 6B stores the difference between server room temperature T1 and suction temperature T2 during normal control, and acquires a relational expression between server room temperature T1 and suction temperature T2 or the value of the difference by machine learning, etc. Then, temperature estimation unit 6B estimates the air temperature using the acquired relational expression or the value of the difference.

[0038] <2.3 Startup control during power outage> <Outline of startup control during power outage> The power failure startup control is a control that uses the temperature difference ΔT and the power failure time Ts to determine the acceleration of the drive frequency and the upper limit drive frequency fmax, and increases the drive frequency to the upper limit drive frequency fmax at the determined acceleration.

[0039] The temperature difference ΔT refers to the difference between the estimated suction temperature T4 and the stopped air conditioner side temperature T5. The estimated suction temperature T4 refers to the temperature estimated by the temperature estimation unit 6B as the suction temperature when the power supply is restored after a power outage.

[0040] The stopped air conditioner side temperature T5 refers to the temperature detected by the suction temperature sensor S2 when the power supply is stopped. In this embodiment, it is the latest suction temperature T2 among the suction temperatures T2 stored for the above machine learning.

[0041] The power failure time Ts refers to the time from when the power supply is stopped to when the power supply is restored. The upper limit drive frequency fmax is the drive frequency at which the power failure startup control is terminated. In other words, when the drive frequency reaches the upper limit drive frequency fmax, the control device 6 shifts the control of the compressor 2 to normal control.

[0042] <Details of startup control during power outage> In the power failure startup control of this embodiment, the control device 6 determines the startup control to be executed from among three startup control patterns based on the temperature difference ΔT and the power failure duration Ts, and then executes the determined startup control (see FIG. 2).

[0043] <First startup control pattern> The first startup control pattern is startup control that is executed when the temperature difference ΔT is less than a predetermined value (for example, 5 deg) and greater than 0 deg, and the power outage time Ts is equal to or longer than a predetermined time (for example, 5 min).

[0044] Hereinafter, the acceleration of the drive frequency in the first startup control pattern is referred to as the reference acceleration, and the upper limit drive frequency fmax in the first startup control pattern is referred to as the reference upper limit frequency. The reference acceleration and the reference upper limit frequency are stored in advance in a ROM or the like.

[0045] <Second startup control pattern> The second startup control pattern is a startup control that is executed when the temperature difference ΔT is equal to or greater than the above-mentioned predetermined value, and is a startup control that increases the drive frequency at an acceleration that is greater than the reference acceleration.

[0046] In other words, when the temperature difference ΔT is 5 degrees or more, the control device 6 increases the drive frequency at the above acceleration regardless of the length of the power outage time Ts (see FIG. 2). Note that the upper limit drive frequency fmax related to the second startup control pattern is the same as the reference upper limit frequency.

[0047] <Third startup control pattern> The third startup control pattern is a startup control that is executed when the temperature difference is less than the above-mentioned predetermined value and is greater than 0 deg, and the power outage time Ts is less than the above-mentioned predetermined time. Then, the control device 6 increases the drive frequency to the reference upper limit frequency at an acceleration smaller than the reference acceleration.

[0048] <3. Features of the Air Conditioner According to the Present Embodiment (Especially, Start-up Control During Power Outage)> It is rare for the air temperature in the server room to be the same throughout (uniform temperature). However, the air drawn into the blower 5A is sufficiently mixed (stirred) before it reaches the evaporator 5, so that the temperature of the air that reaches the evaporator 5 is almost uniform.

[0049] In other words, the air that is sucked in from the server room and reaches the evaporator 5 has a temperature that appropriately indicates the air temperature in the server room (hereinafter referred to as the appropriate temperature). Therefore, in normal control, the drive frequency is controlled so that the suction temperature T2 becomes the set temperature.

[0050] When a power outage occurs, the blower 5A stops, but the ICT equipment continues to operate even during the power outage by receiving power from the UPS. For this reason, the difference between the ambient temperature of the intake temperature sensor S2 and the server room temperature T1 increases as the power outage continues.

[0051] Therefore, when the power supply is restored, that is, immediately after the power is restored, the temperature detected by the intake temperature sensor S2 (intake temperature T2) is lower than the temperature of the server room temperature T1. Moreover, the longer the power outage time Ts, the greater the difference between the server room temperature T1 and the intake temperature T2 immediately after the power is restored.

[0052] Therefore, if the acceleration of the drive frequency and the upper limit drive frequency fmax are determined using the suction temperature T2 immediately after power reconversion, there is a high possibility that the cooling capacity will be insufficient and that the operation of the compressor 2 will not be properly controlled.

[0053] In response to this, after power regeneration, it is possible to determine the acceleration of the drive frequency and the upper limit drive frequency fmax using the suction temperature T2 when the time required for the suction temperature T2 to reach the optimum temperature after the blower 5A starts operating (hereinafter referred to as the optimum time) has elapsed.

[0054] However, in this method, the compressor 2 cannot be started until the appropriate time has elapsed after the power is restored, so the air temperature in the server room further increases. Incidentally, the appropriate time is generally about several minutes.

[0055] In contrast, in this embodiment, the ambient temperature of the suction temperature sensor S2 (estimated suction temperature T4) is estimated using the server room temperature T1, and the estimated suction temperature T4 is used to determine the startup control pattern to be executed in the power outage startup control.

[0056] Therefore, in this embodiment, the compressor 2 can be started before the appropriate time has elapsed after power is restored. As a result, even if a power outage occurs, the air temperature in the server room is prevented from rising significantly (see FIG. 3).

[0057] In this embodiment, when a power outage occurs in the commercial power supply, power is supplied from the engine-driven emergency power supply device to the air conditioner to restore power. The engine-driven emergency power supply device takes a longer time to restore power than an emergency power supply using a storage battery such as a UPS.

[0058] Furthermore, the power that the emergency power supply can supply is smaller than that of a commercial power supply. Therefore, if the compressor 2 is started under the same conditions (for example, the second start-up control pattern) regardless of the temperature difference ΔT and the power outage time Ts, the emergency power supply may be overloaded.

[0059] However, in this embodiment, the compressor 2 is started by selecting a startup control pattern based on the temperature difference ΔT and the power outage duration Ts, thereby suppressing pressure on the emergency power supply device and preventing the air temperature in the server room from rising significantly.

[0060] (Other embodiments) In the above embodiment, the server room is divided into a cold aisle (a space for supplying cold air) and a hot aisle (a space for exhausting hot air), and the room temperature sensor S1 detects the air temperature in the cold aisle. However, the present disclosure is not limited to this.

[0061] That is, the disclosure may be applicable to, for example, a configuration in which the room temperature sensor S1 detects the air temperature in a hot aisle, or a configuration in which the server room is not separated into a cold aisle and a hot aisle.

[0062] In the third startup control pattern according to the embodiment described above, the control device 6 increases the drive frequency to the reference upper limit frequency at an acceleration smaller than the reference acceleration, but the present disclosure is not limited to this.

[0063] That is, in the disclosure, for example, in the third startup control pattern, the control device 6 may increase the drive frequency at the reference acceleration up to an upper limit drive frequency fmax that is lower than the reference upper limit frequency.

[0064] In the above embodiment, when the temperature difference ΔT is equal to or greater than a predetermined value, the increase acceleration of the drive frequency is the same regardless of the power failure time Ts. However, the present disclosure is not limited to this. That is, the present disclosure may be configured such that, for example, even when the temperature difference ΔT is equal to or greater than a predetermined value, the increase acceleration differs depending on the power failure time Ts.

[0065] The temperature estimation unit 6B according to the embodiment described above stores the difference between the server room temperature T1 and the suction temperature T2 during normal control, and obtains the relational equation between the server room temperature T1 and the suction temperature T2 or the value of the difference through machine learning or the like.

[0066] However, the present disclosure is not limited to this. That is, the present disclosure may be configured, for example, to store a relational expression or a value in advance as a relational expression between the server room temperature T1 and the suction temperature T2 or a value of the difference, and to estimate the suction temperature using the relational expression or a value.

[0067] In the above embodiment, the compressor 2 is controlled so that the suction temperature T2 becomes the set temperature. However, the present disclosure is not limited to this. That is, the present disclosure may be configured such that the compressor 2 is controlled so that the blowing temperature T3 becomes the set temperature, for example.

[0068] Temperature estimation unit 6B in this configuration estimates the air temperature after heat exchange in evaporator 5, that is, the blowing temperature, using server room temperature T1. The airflow rate of blower 5A in this configuration may be determined as a function value of the drive frequency.

[0069] The air conditioner according to the embodiment described above is configured to directly cool the air to be supplied to the room by the evaporator 5. However, the present disclosure is not limited to this. That is, the present disclosure may be configured to indirectly cool the air to be supplied to the room by supplying cold water cooled by the evaporator 5 to an indoor heat exchanger such as an air handling unit, for example.

[0070] The air conditioner according to the above embodiment is an air conditioner that cools a space to be air-conditioned. However, the present disclosure is not limited to this. That is, the present disclosure is also applicable to, for example, heating that utilizes heat generated by the condenser 3.

[0071] In the power failure startup control according to the above embodiment, the startup control is determined from among three startup control patterns using the temperature difference ΔT and the power failure time Ts. However, the present disclosure is not limited to this. That is, the present disclosure may be configured to determine at least the acceleration of the drive frequency using the temperature difference ΔT and the power failure time Ts, and to perform startup control by controlling the drive frequency to increase at the determined acceleration.

[0072] The air conditioner according to the above embodiment includes an engine-driven power supply device as an emergency power supply device. However, the present disclosure is not limited to this. That is, the present disclosure may include, for example, a configuration that does not include an emergency power supply device, or a configuration that includes an emergency power supply device that is configured with a storage battery.

[0073] Furthermore, the present disclosure is not limited to the above-mentioned embodiments as long as it is consistent with the gist of the disclosure described in the above-mentioned embodiments. Therefore, the present disclosure may be a configuration in which at least two of the above-mentioned embodiments are combined, or a configuration in which any of the components illustrated or the components described with reference numerals in the above-mentioned embodiments are eliminated. [Explanation of symbols]

[0074] 1. Freezer 2. Compressor 3… Heatsink 4… Pressure reducer 5. Evaporator 5A…Blower 6... Control device S1... Room temperature sensor S2: Intake temperature sensor S3: Air outlet temperature sensor

Claims

1. In an air conditioner using a refrigerator having an electric compressor, a heat exchanger that cools or heats air drawn from a space to be air-conditioned and supplies the air to the space to be air-conditioned; a room temperature sensor that detects an air temperature in a space to be air-conditioned and that is supplied with power from an uninterruptible power supply at least during a power outage; an air conditioner temperature sensor that detects the air temperature before heat exchange in the heat exchanger or the air temperature after heat exchange in the heat exchanger (hereinafter, these temperatures are referred to as air conditioner side temperatures); The frequency of the drive current that drives the compressor (hereinafter referred to as the drive frequency) A drive control unit that controls the drive frequency at least in a power failure startup control or a normal control; a temperature estimation unit that estimates an air conditioner side temperature from the temperature detected by the room temperature sensor by utilizing a difference between a temperature detected by the room temperature sensor and a temperature detected by the air conditioning temperature sensor when the compressor is operating under the normal control, The power failure startup control is a control executed when power supply is restored after power supply is stopped, The normal control is a control that is executed after the end of the power failure startup control, and is a control that adjusts a drive frequency so that a detected temperature of the air conditioning temperature sensor becomes a preset temperature, The temperature estimated by the temperature estimation unit as the air conditioner side temperature when the power supply is restored is defined as the estimated air conditioner side temperature, and the temperature detected by the air conditioner temperature sensor when the power supply is stopped is defined as the stopped air conditioner side temperature, The temperature difference is the difference between the estimated air conditioner side temperature and the air conditioner side temperature when it is stopped, and the power outage time is the time from when the power supply is stopped to when the power supply is restored. An air conditioning device, wherein the drive control unit determines at least an acceleration of a drive frequency using a temperature difference and a power outage duration, and the power outage startup control is control for increasing the drive frequency at the determined acceleration.

2. In an air conditioner using a refrigerator having an electric compressor, a heat exchanger that cools or heats air drawn from a space to be air-conditioned and supplies the air to the space to be air-conditioned; a room temperature sensor that detects an air temperature in a space to be air-conditioned and that is supplied with power from an uninterruptible power supply at least during a power outage; an air conditioner temperature sensor that detects the air temperature before heat exchange in the heat exchanger or the air temperature after heat exchange in the heat exchanger (hereinafter, these temperatures are referred to as air conditioner side temperatures); The frequency of the drive current that drives the compressor (hereinafter referred to as the drive frequency) A drive control unit that controls the drive frequency at least in a power failure startup control or a normal control; a temperature estimation unit that estimates an air conditioner side temperature from the temperature detected by the room temperature sensor by utilizing a difference between a temperature detected by the room temperature sensor and a temperature detected by the air conditioning temperature sensor when the compressor is operating under the normal control, The power failure startup control is a control that is executed when power supply is restored after power supply is stopped, and has at least three startup control patterns, The normal control is a control that is executed after the power failure startup control is terminated, and is a control that adjusts a drive frequency so that a detected temperature of the air conditioning temperature sensor becomes a preset temperature, The temperature estimated by the temperature estimation unit as the air conditioner side temperature when the power supply is restored is defined as the estimated air conditioner side temperature, and the temperature detected by the air conditioner temperature sensor when the power supply is stopped is defined as the stopped air conditioner side temperature, The temperature difference is the difference between the estimated air conditioner side temperature and the air conditioner side temperature when it is stopped, and the power outage time is the time from when the power supply is stopped to when the power supply is restored. A first start-up control pattern among the three start-up control patterns is a start-up control that is executed when the temperature difference is less than a predetermined value and the power outage time is equal to or longer than a predetermined time, A second startup control pattern among the three startup control patterns is a startup control that is executed when a temperature difference is equal to or greater than a predetermined value, and is a startup control that increases and changes a drive frequency at a rate greater than that of the first startup control pattern. The third startup control pattern of the three startup control patterns is a startup control that is executed when the temperature difference is less than a predetermined value and the power outage duration is less than a predetermined time, and is a startup control that increases the drive frequency at an acceleration slower than the first startup control pattern, or a startup control that ends when the drive frequency reaches a predetermined drive frequency that is lower than the drive frequency at the end of the first startup control pattern.

3. 3. The air conditioning system according to claim 1, wherein the room temperature sensor detects the temperature of air before it is heated by a heating element disposed in the space to be air-conditioned.

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