JP2011232013A - Air conditioner, and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner and a control method thereof, capable of quickly matching a room temperature with a set temperature by means of automatic temperature control.SOLUTION: Room fans 23a and 23b send conditioning air. Room temperature sensors 27a and 27b detect a temperature of the room which is cooled or heated by the conditioning air blown out by the room fans 23a and 23b. A control section 18 reduces an air volume of the room fans 23a and 23b in principle when a difference between the set temperature and the room temperature detected by the room temperature sensors 27a and 27b becomes small. However, automatic temperature control is performed in such a way that the air volume of the room fans 23a and 23b is increased if the reduction in temperature difference within a set time period after the air volume of the room fans 23a and 23b is reduced goes below a set value set in advance.

Description

  The present invention relates to an air conditioner and a control method thereof, and more particularly to an air conditioner using a fan for air conditioning and a control method thereof.

  In the automatic temperature control of the air conditioner, it is effective to increase the air volume of the air conditioner in order to quickly bring the room temperature of each room of the building close to the set temperature. However, when the air volume of the air conditioner is increased, hunting reduction in which the room temperature fluctuates near the set temperature becomes significant. Therefore, conventionally, as described in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 57-77218), control is performed to reduce the air volume of the air conditioner as it approaches the set temperature.

  However, if the air volume of the air conditioner is reduced, the time until the set temperature is reached may be too long. Further, depending on the state of the room to be controlled, there is a case where the air conditioning capacity becomes too small with respect to the load due to the reduction of the air volume, so that the set temperature is not reached.

  An object of the present invention is to provide an air conditioner and a method for controlling the same that can quickly match the room temperature to the set temperature in automatic temperature control.

  An air conditioner according to a first aspect of the present invention includes a fan, a temperature sensor, and a control unit. The fan blows conditioned air. A temperature sensor is for detecting the space temperature of the space cooled or heated by the conditioned air blown out by the fan. When the temperature difference between the space temperature detected by the temperature sensor and the set temperature becomes small, the control unit reduces the air flow of the fan to reduce the cooling capacity or heating capacity, and within the set time after the fan air volume is reduced. When the temperature difference decreases below the first set value, automatic air temperature control is performed to increase the cooling capacity or heating capacity by increasing the air volume of the fan.

  According to the apparatus according to the first aspect, in principle, when the temperature difference between the space temperature detected by the temperature sensor and the set temperature is reduced by the control unit, the air volume of the fan is reduced to reduce the cooling capacity or the heating capacity. . As a result, the space temperature can be gradually brought close to the set temperature. However, when the cooling capacity or heating capacity is insufficient due to the decrease in the fan air volume, the decrease in the temperature difference within the set time after the fan air volume is decreased will be lower than the first set value. Automatic temperature control that increases the cooling capacity or heating capacity by increasing the air volume of the fan can be performed. Thereby, the time for the space temperature to converge to the set temperature can be reduced, and the space temperature can be quickly matched with the set temperature.

  An air conditioner according to a second aspect of the present invention is the apparatus according to the first aspect, wherein the control unit obtains a decreasing tendency of the temperature difference near the time point when the temperature sensor detects that the space temperature has reached the set temperature. The first set value is adjusted according to the load estimated from the decreasing tendency of the temperature difference.

  According to the apparatus according to the second aspect, since the first set value is adjusted according to the load by the control unit, the time until the space temperature reaches the set temperature because the value of the first set value is not appropriate. Can be prevented from growing.

  An air conditioner according to a third aspect of the present invention is the heat exchanger according to the first aspect or the second aspect, wherein heat is exchanged between the air blown by the fan and the refrigerant to generate conditioned air. Is further provided. The control unit performs control such that the degree of superheat or the degree of supercooling of the refrigerant in the heat exchanger is constant when the air volume of the fan is automatically controlled.

  According to the apparatus according to the third aspect, the control in the control unit is simplified by not changing the degree of superheat or supercooling and the air volume of the fan simultaneously in the control for automatic temperature control.

In the air conditioner according to the fourth aspect of the present invention, in the apparatus according to the first aspect from the first aspect, the control unit is farther away from zero than the first temperature range and the first temperature range close to zero with respect to the temperature difference. At least two zones with the second temperature range are provided, and the first set value when the temperature difference enters the first temperature range is set larger than the first set value when the temperature difference enters the second temperature range According to the apparatus according to the fourth aspect, since the first set value is set large in the first temperature range and small in the second temperature range, it is easy to determine that the capacity is insufficient in the second temperature range. On the other hand, since it is difficult to determine that the capacity is insufficient in the first temperature range, it is easy to increase the capacity in the second temperature range, so that the space temperature can be quickly brought close to the set temperature, while the capacity is determined to be insufficient in the first temperature range. It is possible to prevent the space temperature from being lowered too much due to an error in The

  An air conditioner according to a fifth aspect of the present invention is the apparatus according to the fourth aspect, wherein the control unit is provided with a second set value smaller than the first set value in the first temperature range, and the temperature within the set time. If the difference is smaller than the first set value but greater than the second set value, the temperature automatic control is performed so as to maintain the current fan air volume.

According to the device of the fifth aspect, even if the decrease in the temperature difference within the set time is smaller than the first set value, the current fan air volume is maintained when the temperature difference is larger than the second set value, so the fan air volume is increased. Less misjudgment to increase fan airflow when it should not.
The control method of the air conditioning apparatus which concerns on the 6th viewpoint of this invention is equipped with the temperature detection process, the 1st air volume control process, the temperature difference reduction value acquisition process, and the 2nd air volume control process. In the temperature detection step, the temperature of the space where the conditioned air is blown by the fan) is detected. In the first air volume control process, the air volume of the fan is decreased according to the decrease in the temperature difference between the space temperature and the set temperature in accordance with the detection result of the temperature detection process. In the temperature difference decrease value acquisition step, the temperature difference decrease value within the set time is obtained for the temperature difference near the detection time point in the temperature detection step within the set time after the first air volume control step. In the second air volume control step, the fan air volume is increased when the temperature difference decrease value acquired in the temperature difference decrease value acquisition step is below the set value.

  According to the method of the sixth aspect, in principle, when the temperature difference between the space temperature detected in the temperature detection step and the set temperature is reduced by the first air flow control step, the fan air flow is reduced. As a result, the space temperature can be gradually brought close to the set temperature. However, when the cooling capacity or the heating capacity is insufficient due to the decrease in the fan air volume, the decrease in the temperature difference within the set time after the fan air volume is decreased is lower than the set value. The air volume of the fan can be increased by the air volume control process. Thereby, the time for the space temperature to converge to the set temperature can be reduced, and the space temperature can be quickly matched with the set temperature.

  A control method for an air conditioner according to a seventh aspect of the present invention is the method according to the sixth aspect, wherein the second air volume control step reduces the temperature difference near the point in time when it is detected that the space temperature has reached the set temperature. It includes a set value adjustment step of obtaining a tendency and adjusting the set value according to the load estimated from the decreasing tendency of the temperature difference.

  According to the method according to the seventh aspect, since the set value is adjusted in accordance with the load in the second air volume control step, the time until the space temperature reaches the set temperature is increased because the set value is not appropriate. It is possible to prevent problems such as

  In the air conditioner according to the first aspect of the present invention, when the cooling capacity or the heating capacity is insufficient, the control unit increases the air volume of the fan, so that the time for the space temperature to converge to the set temperature is reduced and the space temperature is set. It can be quickly matched to the temperature.

  In the air conditioner according to the second aspect of the present invention, it is possible to prevent the time until the space temperature reaches the set temperature from being increased, and the time for the space temperature to approach the set temperature within a range where hunting does not increase is further shortened. And it can be surely reached.

  In the air conditioning apparatus according to the third aspect of the present invention, since the control in the control unit is simple, the space temperature can be made to reach the set temperature steadily.

  In the air conditioner according to the fourth aspect of the present invention, the temperature difference is changed by changing the first set value between the first temperature range near zero and the second temperature range farther from zero than the first temperature range. Where the difference is large, emphasis can be placed on reducing the temperature difference quickly, and if the temperature difference is small, emphasis can be placed on ensuring that there is no misjudgment rather than quickly reducing the temperature difference. It is possible not only to shorten the time for approaching the set temperature, but also to reach it reliably.

  In the air conditioner according to the fifth aspect of the present invention, since it is possible to accurately determine that the fan air volume is increased in the first temperature range where the temperature difference is close to zero, the occurrence frequency of hunting can be suppressed. it can.

  In the control method for an air conditioner according to the sixth aspect of the present invention, when the cooling capacity or the heating capacity is insufficient, the air volume of the fan is increased in the second air volume control step, so the time for the space temperature to converge to the set temperature is reduced. Thus, the space temperature can be quickly matched with the set temperature.

  In the control method of the air conditioning apparatus according to the seventh aspect of the present invention, it is possible to prevent the time until the space temperature reaches the set temperature from being increased, and the time for the space temperature to approach the set temperature within a range where hunting does not increase. Can be made shorter and more reliable.

The figure which shows the outline | summary of a structure of the air conditioning apparatus which concerns on one Embodiment. The block diagram for demonstrating control of the control part of the air conditioning apparatus of FIG. The flowchart which shows the procedure of the air volume automatic control driving | operation at the time of air_conditioning | cooling. The flowchart which shows the procedure of air volume automatic determination. The flowchart which shows the procedure of the air volume automatic control driving | operation at the time of heating. The conceptual diagram for demonstrating correction | amendment of air volume automatic control driving | operation. The flowchart which shows the correction | amendment procedure of air volume automatic control driving | operation.

(1) Whole structure In FIG. 1, the outline | summary of the whole structure of the air conditioning apparatus which concerns on one Embodiment of this invention is shown. An air conditioner 10 shown in FIG. 1 mainly includes an outdoor unit 11 as a heat source unit, a plurality of (two in the present embodiment) indoor units 12a and 12b as utilization units, an outdoor unit 11 and an indoor unit. A liquid refrigerant communication pipe 13 and a gas refrigerant communication pipe 14 are provided as refrigerant pipes for connecting 12a and 12b. The air conditioner 10 circulates a refrigerant between the outdoor unit 11 and the indoor units 12a and 12b via the liquid refrigerant communication pipe 13 and the gas refrigerant communication pipe 14, and performs a vapor compression refrigeration cycle operation. It is a device used for air conditioning such as air conditioning in a room such as a building.

  In the air conditioner 10, the outdoor unit 11 and the indoor units 12a and 12b are connected by a liquid refrigerant communication pipe 13 and a gas refrigerant communication pipe 14 to constitute a refrigeration circuit. The plurality of indoor units 12a and 12b are connected in parallel to each other between the liquid refrigerant communication pipe 13 and the gas refrigerant communication pipe 14.

(2) Detailed Configuration (2-1) Indoor Unit The indoor units 12a and 12b are installed by being embedded in a ceiling of a room such as a building, suspended from the ceiling, or hung on a wall surface of the room. One or a plurality of indoor units 12a and 12b are installed in each room.

  The indoor units 12a and 12b shown in FIG. 1 have the same configuration, that is, electric valves 21a and 21b, indoor heat exchangers 22a and 22b, indoor fans 23a and 23b, brushless DC motors 24a and 24b, and a liquid side temperature sensor. 25a, 25b, gas side temperature sensors 26a, 26b, indoor temperature sensors 27a, 27b, and indoor side control units 28a, 28b are respectively provided therein. Since the indoor units 12a and 12b have the same configuration, the configuration of the indoor unit 12a will be described below, and the description of the configuration of the indoor unit 12b will be omitted.

  The electric valve 21a and the indoor heat exchanger 22a are connected in series from the liquid refrigerant communication pipe 13 to the gas refrigerant communication pipe 14 in this order by a pipe inside the indoor unit 12a. That is, the motor operated valve 21 a is connected to one end of the indoor heat exchanger 22 a, and the other end of the indoor heat exchanger 22 a is connected to the gas refrigerant communication pipe 14. The motor-operated valve 21a is connected to the liquid side of the indoor heat exchanger 22a in order to adjust the flow rate of the refrigerant flowing in the indoor heat exchanger 22a, and in response to a pulse signal from the indoor side control unit 28a. Open / close control is performed.

  Indoor air in which heat is exchanged with the refrigerant in the indoor heat exchanger 22a is sucked into the indoor unit 12a by an indoor fan 23a provided in the indoor unit 12a. The indoor fan 23a has a brushless DC motor 24a as a drive source. By controlling the rotation speed of the brushless DC motor 24a, the amount of air supplied to the indoor heat exchanger 22a (air volume) can be varied. A fan who can. The rotation speed of the brushless DC motor 24a is controlled by a control signal from the indoor side control unit 28a.

  In order to reliably control the indoor unit 12a, the indoor unit 12a is provided with a liquid temperature sensor 25a for detecting the refrigerant temperature on the liquid side of the indoor heat exchanger 22a, and on the gas side of the indoor heat exchanger 22a. A gas side temperature sensor 26a for detecting the refrigerant temperature is attached. An indoor temperature sensor 27a is attached to the inlet side of the indoor unit 12a, and the indoor temperature sensor 27a detects the temperature of the indoor air flowing into the indoor unit 12a. The indoor temperature sensor 27a is composed of, for example, a thermistor.

  The operation of each part of the indoor unit 12a is controlled by the indoor side control unit 28a, and an instruction for the operation of the indoor unit 12a to the indoor side control unit 28a is a remote controller (not shown) or an outdoor side control unit of the outdoor unit 11 described later. Sent from

(2-2) Outdoor unit The outdoor unit 11 releases the thermal energy that the indoor units 12a and 12b take in from the indoor air during cooling, or the thermal energy that the indoor units 12a and 12b gives to the indoor air during heating from the outdoor. It is installed outside the building, such as on the roof of a building, for taking in.

  For this purpose, the outdoor unit 11 is connected to the liquid refrigerant communication pipe 13 and the gas refrigerant communication pipe 14 to constitute a refrigeration circuit. Therefore, the outdoor unit 11 mainly includes an electric valve 31, an outdoor heat exchanger 32, a four-way switching valve 33, and a compression. A machine 34 and an accumulator 36 are provided.

  An electric valve 31 is connected to the liquid refrigerant communication pipe 13, one end of the outdoor heat exchanger 32 is connected to the electric valve 31, and the first port of the four-way switching valve 33 is connected to the other end of the outdoor heat exchanger 32. It is connected. The four-way switching valve 33 has the second port to the fourth port in addition to the first port, the discharge port of the compressor 34 is connected to the second port, and the gas refrigerant communication pipe is connected to the third port. 14 and an accumulator 36 is connected to the fourth port. An accumulator 36 is connected to the suction port of the compressor 34, and the refrigerant returned to the accumulator 36 is supplied to the compressor 34. The compressor 34 is a capacity type compressor that is driven by a motor 35 controlled by an inverter and can change an operation capacity.

  At the time of cooling, in the four-way selector valve 33, the first port and the second port are connected, and the third port and the fourth port are connected. As a result, the refrigerant compressed by the compressor 34 is sent to the outdoor heat exchanger 32, the outdoor heat exchanger 32 functions as a condenser, and the indoor heat exchangers 22a, 22b function as evaporators, thereby removing indoor air. Cooling.

  When the air volume automatic control operation is selected during cooling, the motor valves 21a, 21b, 31 and the compressor 34 are controlled so that the degree of superheat becomes constant, and the cooling capacity is determined according to the air volume. That is, in the air volume automatic control operation during cooling, when the air volume is large, the cooling capacity is high, and when the air volume is small, the cooling capacity is low. Since the automatic temperature control at this time is performed solely by increasing or decreasing the air volume, the air volume is automatically switched for temperature control.

  During heating, in the four-way selector valve 33, the first port and the fourth port are connected and the second port and the third port are connected. Accordingly, the refrigerant compressed by the compressor 34 is sent to the indoor heat exchangers 22a and 22b, and the indoor heat exchangers 22a and 22b function as condensers, and the indoor air is heated by the indoor heat exchangers 22a and 22b. .

  When the air volume automatic control operation is selected during heating, the motor valves 21a, 21b, 31 and the compressor 34 are controlled so that the degree of supercooling is constant, and the heating capacity is determined according to the air volume. That is, in the air volume automatic control operation during heating, the heating capacity is high when the air volume is large, and the heating capacity is low when the air volume is small. Since the automatic temperature control at this time is performed solely by increasing or decreasing the air volume, the air volume is automatically switched for temperature control.

  An outdoor fan 37 is also provided in the outdoor unit 11, and the outdoor fan 37 supplies outdoor air to the outdoor heat exchanger 32 for heat exchange with the refrigerant in the outdoor heat exchanger 32.

  The outdoor unit 11 is provided with various sensors. Specifically, the outdoor unit 11 detects the suction pressure sensor 41 that detects the suction pressure of the compressor 34, the discharge pressure sensor 42 that detects the discharge pressure of the compressor 34, and the suction temperature TSS of the compressor 34. An intake temperature sensor 43 and a discharge temperature sensor 44 for detecting the discharge temperature TDD of the compressor 34 are provided. The suction temperature sensor 43 is provided at a position between the accumulator 36 and the compressor 34. The outdoor heat exchanger 32 includes a heat exchange temperature sensor 45 that detects the temperature of the refrigerant flowing in the outdoor heat exchanger 32 (that is, the refrigerant temperature corresponding to the condensation temperature during the cooling operation or the evaporation temperature during the heating operation). Is provided. A liquid side temperature sensor 46 that detects the temperature of the refrigerant is provided on the liquid side of the outdoor heat exchanger 32. An outdoor temperature sensor 47 that detects the temperature of the outdoor air flowing into the unit (that is, the outdoor temperature) is provided on the outdoor air inlet side of the outdoor unit 11. The suction temperature sensor 43, the discharge temperature sensor 44, the heat exchange temperature sensor 45, the liquid side temperature sensor 46, and the outdoor temperature sensor 47 are composed of thermistors.

  In addition, the outdoor unit 11 has an outdoor control unit 48 that controls the operation of each unit constituting the outdoor unit 11. The outdoor control unit 48 includes a microcomputer, a memory 18b, a timer 18c, an inverter circuit that controls the motor 38, and the like, which are provided to control the outdoor unit 11, and the indoor units 12a, 12b. Control signals and the like can be exchanged with the indoor side control units 28a and 28b via the transmission line 18a. That is, the overall operation of the air conditioner 10 is controlled by the indoor side control units 28a and 28b, the outdoor side control unit 48, and the transmission line 18a connecting the indoor side control units 28a and 28b and the outdoor side control unit 48. A control unit 18 is configured.

  As shown in FIG. 2, which is a block diagram relating to control of the air conditioner 10, the control unit 18 is connected so as to receive detection signals from various sensors 25 a to 27 a, 25 b to 27 b, and 41 to 47. The motorized valves 21a, 21b, 31 and other various devices 24a, 24b, 35, 38 are connected based on these detection signals.

(3) Indoor Fan Control Method and Operation A description will be given of the case where the automatic air volume control operation is selected from among the control method and operation of the indoor fan 23a. The air volume automatic control operation is an operation that leaves the air volume setting to the air conditioner 10. The air volume automatic control mode is selected by a remote controller (not shown), and the air volume automatic control operation is started when the indoor control unit 28a receives the command from the remote controller. The automatic air volume control operation of the indoor unit 12a ends when the air volume is manually set from the remote controller or when the operation of the indoor unit 12a ends. In the drawing, the air volume automatic control mode is abbreviated as A mode.

  As described above, during the air volume automatic control operation, the motor is controlled by the electric valve 21a so that the degree of superheat of the indoor heat exchanger 22a is kept constant during cooling, and the degree of supercooling of the indoor heat exchanger 22a during heating. It is controlled by the electric valve 21a so as to be kept constant. Therefore, the cooling capacity and the heating capacity are switched by switching the air volume for automatic temperature control. That is, automatic temperature control is performed by automatic air volume control.

  In both cooling and heating, the air volume of the indoor fan 23a is switched stepwise by switching the rotational speed of the brushless DC motor 24a by the indoor control unit 28a. In this air volume automatic control operation, VII tap, VI tap, V tap, IV tap, III tap, II tap, and I tap are set in order from the larger air volume of the indoor fan 23a.

(3-1) Automatic air volume control during cooling The automatic air volume control during cooling will be described with reference to the flowchart of FIG. In the automatic air volume control mode, the operation of the indoor unit 12a is roughly divided into two types. That is, there are normal operation and operation other than normal operation. “Operation other than normal operation” includes “operation for protecting indoor units” such as “freezing prevention operation” and “defrosting operation”. In operation other than normal operation, the air volume of the indoor fan 23a is fixed regardless of the indoor temperature detected by the indoor temperature sensor 27a of the indoor unit 12a.

  In the automatic air volume control, since the air volume is not determined by an instruction from the user of the indoor unit 12a, it is necessary to determine the air volume when normal operation starts in the automatic air volume control mode (step S10). .

  Therefore, in step S11, the situation at the start of normal operation is determined. When the normal operation is started by starting the indoor unit 12a, the process proceeds to step S12, the air volume is set to the VII tap, and the process proceeds to the next step S15. When the normal operation is started by the indoor unit 12a changing from the thermo-off state to the thermo-on state, the process proceeds to step S13, and the operation is performed for one minute with the tap immediately before the thermo-off, and then the process proceeds to step S15. When the operation other than the normal operation is finished (the operation other than the normal operation is turned off) and the normal operation is started, the operation is performed for one minute with the tap during the operation other than the normal operation, and the process proceeds to the next step S15.

  In step S15, air volume automatic determination for determining the air volume is performed. The automatic air volume determination is performed once every n minutes according to the count of the timer 18c of the control unit 18. In principle, the air volume automatic determination is performed according to the rules shown in Table 1, but is appropriately corrected according to the temperature change situation.

冷房時の風量自動判定においては、表１に示されている温度差Δを室内温度Ｔｃｏｎと設定温度Ｔｓとの差（Ｔｃｏｎ−Ｔｓ）のように定義して用いる。設定温度Ｔｓは、リモートコントローラから室内側制御部２８ａに入力されたり、前回の運転時の設定温度Ｔｓをデフォルト値として制御部１８が保持していたりするものが用いられる。表１に示されているように、温度差ΔＴの大きさによって７つの温度域Ａ〜Ｇが設定されており、室内温度センサ２７ａで検知された室内温度がどの温度域Ａ〜Ｇの中に入るかが判別される。温度域Ｂ〜Ｆは、所定の幅を持って設定されており、温度域Ｆの範囲が０℃＜ΔＴ≦ｔａ℃、温度域Ｅの範囲がｔａ℃＜ΔＴ＜ｔｂ℃、温度域Ｄの範囲がｔｂ℃≦ΔＴ≦ｔｃ℃、温度域Ｃの範囲がｔｃ℃＜ΔＴ≦ｔｄ℃、温度域Ｂの範囲がｔｄ℃＜ΔＴ≦ｔｅ℃である。温度域Ａ，Ｇはこれらの温度域Ｂ〜Ｆの外側の区域を全て含んで設定され、温度域Ａの範囲がΔＴ＞ｔｅ℃、温度域Ｇの範囲が０℃≧ΔＴである。

In the air volume automatic determination at the time of cooling, the temperature difference Δ shown in Table 1 is defined and used as a difference (Tcon−Ts) between the room temperature Tcon and the set temperature Ts. The set temperature Ts is input from the remote controller to the indoor side control unit 28a, or the set temperature Ts held by the control unit 18 with the set temperature Ts at the previous operation as a default value is used. As shown in Table 1, seven temperature ranges A to G are set according to the magnitude of the temperature difference ΔT, and the room temperature detected by the indoor temperature sensor 27a is in which temperature range A to G. It is determined whether it enters. The temperature ranges B to F are set with a predetermined width. The range of the temperature range F is 0 ° C. <ΔT ≦ ta ° C., the range of the temperature range E is ta ° C <ΔT <tb ° C., and the temperature range D. The range is tb ° C ≦ ΔT ≦ tc ° C, the temperature range C is tc ° C <ΔT ≦ td ° C, and the temperature range B is td ° C <ΔT ≦ te ° C. The temperature ranges A and G are set so as to include all the areas outside these temperature ranges B to F, the range of the temperature range A is ΔT> te ° C., and the range of the temperature range G is 0 ° C. ≧ ΔT.

  In principle, the air volume is determined by which temperature range A to G the temperature difference ΔT belongs to. If the temperature range is within the temperature ranges A and B, the VI tap is selected. If it is within the range D, it will be IV tap, if it is in the temperature range E, it will be III tap, if it is in the temperature range G, it will be I tap. As already described, the air volume is the largest for the VII tap, and decreases in the order of VI, V, IV, III, and II, and the I tap is the smallest. Since the air volume is determined in this way, the air volume can be decreased stepwise as the room temperature approaches the set temperature and the temperature difference ΔT approaches 0.

  However, because the indoor conditions vary, the air volume control method shown in Table 1 is not always optimal. For example, since only one indoor unit 12a is set in a room with a large volume, for example, if the air volume is lowered to the II tap, it will take a very long time for the indoor temperature Tcon to reach the set temperature Ts, or the sun or indoors. It may be assumed that people are starting to rise before the room temperature Tcon reaches the set temperature Ts as a heat source.

  When the cooling capacity can be controlled by changing the degree of superheat of the indoor heat exchanger 22a, the cooling capacity can be increased by setting the degree of superheating to a small value when the load is large, without changing the air volume. I was able to. However, in the automatic air volume control operation as described above, the cooling capacity cannot be increased unless the air volume is increased in order to keep the superheat degree constant.

  Therefore, the situation that cannot be dealt with by the automatic air volume judgment of the principle shown in Table 1 is dealt with by making a judgment as shown in FIG. Therefore, the control unit 18 stores the temperature difference ΔT used in the determination made n minutes ago. The temperature difference n minutes ago is represented as ΔTt, and the difference (ΔT−ΔTt) between the current temperature difference ΔT and the temperature difference ΔTt n minutes ago is represented as dΔT. Since this dΔT is a guideline indicating how much the temperature difference ΔT has become small within the set time of n minutes, it will be referred to as a temperature difference decrease or a temperature difference decrease value in the following description. Using such an expression, the correction of the control in Table 1 when the room temperature Tcon cannot be brought close to the set temperature Ts sufficiently quickly by the control in Table 1 will be described along the flowchart of FIG.

  The controller 18 of the air conditioner 10 holds the room temperature Tcon detected by the room temperature sensor 27a (step S28), and the difference (ΔTt) between the room temperature Tcon detected n minutes ago and the set temperature Ts. Then, a decrease value (ΔT−ΔTt) of the temperature difference is obtained from the difference (ΔT) between the detected indoor temperature Tcon and the set temperature Ts (step S29).

  In step S30, it is determined whether or not the room temperature Tcon detected by the room temperature sensor 27a falls within the temperature ranges F and G. When the temperature does not fall within the temperature ranges F and G, it means that the room temperature Tcon is within the temperature range A to E, and the process proceeds to step S31. When entering the temperature range F, G, the process proceeds to step S32.

In step S31, it is determined whether or not the decrease in temperature difference (dΔT) is greater than the threshold value β. The threshold value β is set to a predetermined negative integer value k by default. When the decrease in temperature difference (dΔT) exceeds the threshold value β (dΔT> β), the process proceeds to step S36. When the decrease in temperature difference (dΔT) is equal to or greater than the threshold value β (β = k), it means that the indoor temperature Tcon is greatly increased. In the default setting, the load on the cooling capacity is large. It means that the capacity to cool the room is insufficient. Since the ability is insufficient, the fan tap is raised by one tap in step S36. For example, if the temperature range is changed from the temperature range B to the temperature range C n minutes before the determination in step S32, the current fan tap is “V”, so that it is raised to “VI”.
On the other hand, a decrease in temperature difference (dΔT) equal to or less than the threshold value β means that the temperature is decreasing smoothly. In that case, it progresses to step S35 and the air volume of the indoor fan 23a is determined according to Table 1 as a principle.

When the process proceeds to step S32 because the temperature difference (ΔT) is within the temperature ranges F and G, whether or not the decrease in temperature difference (dΔT) is greater than or equal to α (dΔT ≧ α) in this step. It is determined whether or not β + α or less (dΔT ≦ β + α) or between α and β + α (α>dΔT> β + α). When the decrease in temperature difference (dΔT) is greater than or equal to α, the process proceeds to step S33. If the decrease in the temperature difference is a positive value, it means that the room temperature Tcon has departed from the set temperature Ts, and thus the cooling capacity must be increased. Therefore, in step S33, the fan tap is raised by one tap.
On the other hand, the decrease in temperature difference (dΔT) being equal to or less than the threshold value β + α means that the temperature is decreasing smoothly. In that case, it progresses to step S35 and the air volume of the indoor fan 23a is determined according to Table 1 as a principle.

  When the temperature difference (ΔT) is within the temperature ranges F and G and the decrease in the temperature difference satisfies the condition of α> dΔT> β + α, the process proceeds to step S34, the fan tap is kept as it is, and the air flow rate is changed. Do not make any changes. The fact that the temperature difference (ΔT) is within the temperature ranges F and G means that the room temperature Tcon is equal to or lower than the set temperature Ts + ta ° C. Thus, when the temperature is sufficiently close to the set temperature Ts, it is more comfortable for the user to gradually approach the set temperature Ts than to increase the air volume and cool rapidly. Therefore, the next automatic air volume determination is waited while maintaining the air volume.

  When the automatic air volume determination in steps S30 to S36 is completed, the process proceeds to step S16 shown in FIG. 3, and the control unit 18 issues a command to adjust the fan tap to the indoor fan 23a based on the automatic air volume determination. The indoor fan 23a changes the rotation speed of the brushless DC motor 24a as necessary based on a command from the control unit 18.

  In step S17, it is determined whether or not the set temperature Ts has been changed from a remote controller (not shown). This is because if the set temperature Ts is changed, the difference (ΔT) between the room temperature Tcon and the set temperature Ts changes, and it may be necessary to newly adjust the air volume.

  When the set temperature Ts is changed, in step S18, the air volume is set based on the following predetermined determination. If the indoor fan 23a is stopped due to a thermo-off or the like when the set temperature Ts is changed, or if the immediately preceding fan tap is smaller than the I tap, the air volume is set to the I tap. When the immediately preceding fan tap is any one of I tap to VII tap, the setting of the immediately preceding fan tap is retained. After the air volume setting based on the predetermined determination is performed, the process proceeds to step S15, and the air volume automatic determination is performed again.

  If there is no instruction to change the set temperature by a remote controller or the like, the process proceeds to step S19, and it is determined whether or not an instruction to end normal operation in the air volume automatic control mode has been issued. For example, when there is an instruction to stop the operation, an instruction to turn off the thermostat, or an instruction to perform an anti-freezing operation, this means the end of the normal operation in the air volume automatic control mode. This is because when such an instruction is given, the operation is performed with another determination rule or with a determined air volume, so that the air volume automatic control operation is not performed. If it is determined in step S19 that there is no instruction to end the normal operation in the air volume automatic control mode, the process returns to step S15, and the process is repeated from the air volume automatic determination step. If it is determined in step S19 that there is an instruction to end the normal operation in the air volume automatic control mode, the process proceeds to step S20, and the normal operation in the air volume automatic control mode is ended. However, ending the normal operation in the air volume automatic control mode does not necessarily mean the end of the air volume automatic control mode. This means that the air volume is not automatically set in situations other than normal operation or when the thermo-off is performed.During the automatic air volume control mode, there is no need to set the new automatic air volume control mode. The normal operation (step S10) in the air volume automatic control mode is started by turning off or thermo-ON.

(3-2) Automatic Air Volume Control During Heating Automatic air volume control during heating will be described along the flowchart of FIG. Even during heating, the point that there is a normal operation and an operation other than the normal operation in the air volume automatic control mode is the same as during cooling.

  Then, when normal operation starts in the automatic air volume control mode (step S40), it is necessary to determine the air volume during cooling and during heating. In step S41, normal operation starts in the automatic air volume control mode. It is determined whether it is at the time of start-up, whether it is due to the thermo-on, or because the operation other than the normal operation is turned off.

  When the normal operation is started by starting the indoor unit 12a, the process proceeds to step S42, the air volume is set to the VII tap, and the process proceeds to the next step S45. When the normal operation is started by the indoor unit 12a changing from the thermo-off state to the thermo-on state, the process proceeds to step S43, and the operation is performed for one minute with the tap immediately before the thermo-off, and then the process proceeds to step S45. When the operation other than the normal operation is finished (the operation other than the normal operation is turned off) and the normal operation is started, the operation is performed for 1 minute with the air volume setting based on the predetermined determination described later, and the process proceeds to the next step S45.

  The predetermined determination in step S44 is that when the indoor fan 23a is stopped or the immediately preceding fan tap is smaller than the I tap, the air volume is set to I tap, and the immediately preceding fan tap is any of I tap to VII tap. In some cases, the previous fan tap setting is retained.

  In step S45, the air volume automatic determination for determining the air volume is performed. The automatic air volume determination is performed once every n minutes. In principle, the air volume automatic determination is performed in accordance with the rules shown in Table 2, but is appropriately corrected according to the temperature change situation.

表２は、表１と同じである。表１と表２が同じであることがこの風量自動制御運転の必須の要件ではないが、ここでは同じ規則を用いて暖房時と冷房時の風量自動制御運転を行っている。

Table 2 is the same as Table 1. The fact that Table 1 and Table 2 are the same is not an indispensable requirement for this automatic air volume control operation, but here, the same rule is used to perform the automatic air volume control operation during heating and cooling.

  In the automatic air volume determination during heating, the temperature difference ΔT shown in Table 2 is defined and used as the difference (Ts−Tcon) between the room temperature Tcon and the set temperature Ts.

  While control is mainly performed to bring the low room temperature Tcon closer to the higher set temperature Ts during heating, control is performed mainly to bring the higher room temperature Tcon closer to the lower set temperature Ts during cooling. Therefore, the direction of change in the room temperature Tcon is reversed during heating and cooling. However, when the temperature difference ΔT is defined as described above, the direction of change of the temperature difference ΔT coincides between heating and cooling. Therefore, the description of step S45 for automatic air volume determination is the same as step S15 for automatic air volume determination, and thus the description of step S45 is omitted. Steps S30 to S36 are the same for heating and cooling, and thus the description thereof is omitted.

(3-3) Correction of automatic air volume control operation during cooling and heating (3-3-1) Outline of correction of automatic air volume control operation Indoor structure of a building or the size of an indoor heat source (for example, indoors) Since the load varies depending on the number of humans), it is preferable to perform a method in which the air conditioner 10 performs self-learning and adjustment so that the threshold value β used in the automatic air volume determination is suitable for the load. An adjustment method will be described.

  As described above in (3-1) Automatic air volume control operation during cooling and (3-2) Automatic air volume control operation during heating, the threshold value β used in the automatic air volume determination is “k” as a default value. is there. This means that, in the temperature range A to E, whether or not the temperature decreases at a rate of k ° C. or more in n minutes is used as a criterion for determination. This default value is set to a relatively large absolute value in order to avoid a situation in which the room temperature Tcon does not reach the set temperature Ts in the automatic air volume control operation.

  Further, in the determination in step S34 (see FIG. 4) in the temperature ranges F and G, the value of (β + α), which is a threshold value indicating whether the fan tap is maintained as it is or according to the rules of Table 1 or Table 2, is also used. It depends on the set value of the threshold β. Increasing the threshold value (β + α) means that the room temperature Tcon is gradually brought closer to the set temperature Ts. In other words, increasing the threshold value (β + α) means increasing the timing (period) for reducing the cooling capacity or heating capacity.

  As described above, in order to increase the value of the variable β (decrease the absolute value) by treating the value of the threshold β as a variable, the value is changed while adapting to the load of the space (room) where cooling or heating is performed with conditioned air. It is necessary to do.

  On the contrary, it is assumed that the default value β is not sufficient in some cases. In such a case, it is necessary to reduce the value of the threshold value β (increase the absolute value).

  FIG. 6 shows the concept of changing the slope of the threshold value β. The decrease at a rate of k ° C. for n minutes is the default value, and becomes a reference for the decrease in temperature difference (ΔT−ΔTt) for n minutes. This variable β is changed within the change range Ra to be adapted to the load of the space to be cooled or heated. The values that can be taken by the variable β are discretely in order from the smallest, -t1 ° C / n minutes, -t2 ° C / n minutes, -t3 ° C / n minutes, -t4 ° C / n minutes, -t5 ° C. / N minutes and -t6 ° C./n minutes. In general, since the load in the room where the indoor units 12a and 12b are actually installed is smaller than the load suitable for the variable β = −t3 ° C./n set as the default value, −t 4 ° C./n The area Ar of min to -t6 ° C./n is the target value of the variable β after learning of the air conditioner 10.

(3-3-2) Specific Example of Correction of Air Volume Automatic Control Operation Correction of the air volume automatic control operation will be described with reference to FIGS. 2 and 7. The correction of the air volume automatic control operation is performed by adjusting the threshold value β. Therefore, the air conditioning apparatus 10 stores the value of the threshold value β in the memory 18b of the control unit 18 shown in FIG. In order to perform correction, the room temperature Tcon detected by the room temperature sensors 27a and 27b is stored in the memory 18b. Further, the control unit 18 measures the time from when the previous determination is made by the timer 18c until the room temperature Tcon reaches the set temperature Ts, and the temperature difference ΔT when the room temperature Tcon reaches the set temperature Ts. Can be obtained (ＴΔT / ∂t).

  The timer 18c starts simultaneously with the start of the air volume automatic control operation (step S60). This is to perform automatic air volume determination every n minutes, but at the same time, to measure the time when the room temperature Tcon reaches the set temperature Ts.

  The controller 18 detects the room temperature Tcon by the room temperature sensors 27a and 27b for each determination (every n minutes) (step S61), and stores the difference ΔT between the set temperature Ts and the room temperature Tcon in the memory 18b (step S61). S62).

  Next, the control unit 18 constantly detects the values of the room temperature sensors 27a and 27b, and determines whether or not the room temperature Tcon has reached the set temperature Ts (step S63). If the room temperature Tcon does not reach the set temperature Ts, the process returns to step S61 and the above operation is repeated.

  When the room temperature Tcon reaches the set temperature Ts, the process proceeds from step S63 to step S64, and the time required for the room temperature Tcon to reach the set temperature Ts from the previous determination is stored from the timer 18c. The inclination (∂ΔT / ∂t) of the temperature difference ΔT when the room temperature Tcon reaches the set temperature Ts has been determined since the previous determination of the difference between the room temperature Tcon and the set temperature Ts when the previous determination was made. It is obtained by dividing by the time taken to reach the set temperature (step S65). The room temperature Tcon when the previous determination is made is stored in the memory 18b.

  The correction amount of the threshold value β is derived according to the rules of Table 3 from the slope of the temperature difference ΔT (∂ΔT / ∂t). Note that values v, w, and x described later are positive integers, and v <w. When the slope is 0 or positive (∂ΔT / ∂t ≧ 0), the correction amount of the threshold β is 0. When the slope is smaller than 0 and greater than or equal to −v (0> ∂ΔT / ∂t ≧ −v), the correction amount of the threshold β is −x. When the slope is smaller than −v and larger than −w (−v> ∂ΔT / ∂t ≧ −w), the correction amount of the threshold value β becomes zero. When the slope is equal to or less than −w (∂ΔT / ∂t ≦ −w), the correction amount of the threshold β is x. However, the β value is provided with an upper limit value βmax and a lower limit value βmin.

ステップＳ６７で変更された閾値βは、次回の風量自動判定以降において使用される。

The threshold value β changed in step S67 is used after the next automatic air volume determination.

(5) Features (5-1)
In the air volume automatic control operation, the control unit 18 of the air conditioner 10 basically has a temperature difference ΔT between the indoor temperature Tcon detected by the indoor temperature sensors 27a and 27b and the set temperature Ts set by a remote controller or the like. When it becomes smaller, control is performed to reduce the air volume of the indoor fans 23a and 23b (step S35). Thereby, since the air volume decreases as the indoor temperature Tcon (space temperature) approaches the set temperature Ts, the cooling capacity and the heating capacity gradually decrease, and the speed at which the indoor temperature Tcon approaches the set temperature Ts becomes gentle. . When the speed at which the room temperature Tcon approaches the set temperature Ts is moderate, hunting in which the room temperature Tcon varies across the set temperature Ts is less likely to occur.
However, since the load in the room (space) to be controlled varies, the cooling capacity and the heating capacity may be insufficient with respect to the load when the air volume set in advance is reduced. In particular, the air conditioner 10 controls the degree of superheat in the indoor heat exchangers 22a and 22b during cooling and the degree of supercooling in the indoor heat exchangers 22a and 22b during heating. Since the cooling capacity and the heating capacity are directly controlled by the control, the control is simple and the room temperature Tcon can be made to reach the set temperature Ts steadily, but such a tendency is remarkable.
The air conditioner 10 obtains the decrease value (ΔT−ΔTt) of the temperature difference ΔT for n minutes (within the set time) even after the air volume is decreased by the control unit 18, and this decrease value is obtained. If (ΔT−ΔTt) does not reach a predetermined value (threshold value β in temperature ranges A to E, α in temperature ranges F and G), the air volume is increased (steps S33 and S36). When the air volume increases, the cooling capacity or the heating capacity increases, so that it is possible to prevent a problem that the room temperature Tcon does not reach the set temperature Ts due to the lack of capacity or the arrival becomes extremely slow. As a result, the time for the room temperature Tcon to converge to the set temperature Ts can be reduced, and the room temperature Tcon can be quickly matched with the set temperature Ts.

  As shown in FIG. 4, the control unit 18 uses different criteria for determination in step S31 and step S32. In step S31, a determination is made when the temperature difference ΔT is in the temperature range A to E (second temperature range), and a negative value is used for the threshold β value (first set value, set value). It has been. That is, if the decrease value dΔT (= ΔT−ΔTt) of the temperature difference is larger than β, it is determined that the room temperature Tcon has not approached the set temperature Ts smoothly. On the other hand, in step S32, a determination is made when the temperature difference ΔT is in the temperature range F (first temperature range), and α is used as the threshold value (first set value, set value). . That is, if the decrease value dΔT of the temperature difference is greater than t5 ° C./n, it is determined that the room temperature Tcon has not approached the set temperature Ts smoothly.

  Since the threshold value is set to be large in the temperature range F and small in the temperature range A to E, the temperature range A to E is easily determined to be insufficient in capacity, whereas in the temperature range F, it is difficult to be determined to be insufficient capacity. For this reason, in the temperature ranges A to E, it becomes easy to increase the capacity, so that the room temperature Tcon can be quickly brought close to the set temperature Ts. On the other hand, in the temperature range F, it is possible to prevent the indoor temperature Tcon from being excessively lowered due to an error in determining whether the capacity is insufficient. That is, in the temperature range F, the room temperature Tcon is extremely close to the set temperature Ts, so that the user does not feel uncomfortable even if it takes a long time from there, and the room temperature Tcon is easily held in the vicinity of the set temperature Ts. Is preferred.

  Further, as shown in FIG. 4, the control unit 18 uses β + α as a value (second set value) smaller than the threshold value α in the temperature range F in step S32 to maintain the fan air volume as it is. Judgment is made. Even if the decrease in temperature difference (dΔT) for n minutes (within the set time) is smaller than α (first set value) but greater than β + α (second set value), the current air flow of the fan is maintained (step S34). ). By performing such temperature control, it is less likely to make a determination to increase the air volume of the indoor fans 23a and 23b when the air volume of the indoor fans 23a and 23b should not be increased.

  In other words, when the decrease in temperature difference (dΔT) is between (β + α) and α, the determination is suspended and the state is further observed for n minutes, and the determination time is doubled. It has the same effect as extending to 8 minutes. By looking at the decrease in temperature difference (dΔT) over a long period of time, the accuracy and accuracy of judgment are improved.

(5-2)
In the control unit 18 of the air conditioner 10, as shown in FIG. 7, the temperature difference near the point in time when the indoor temperature sensor 27a detects that the indoor temperature Tcon (space temperature) has reached the set temperature Ts (Ｔ ΔT / ∂t) is obtained (step S66). And the control part 18 adjusts threshold value (beta) (1st setting value) according to the load estimated from the decreasing tendency (∂ΔT / ∂t) of the temperature difference according to the rules shown in Table 3 (step S67). ). By performing such adjustment, it is possible to prevent problems such as an increase in the time until the room temperature Tcon reaches the set temperature Ts due to the threshold value β not being appropriate for the indoor state.

(6) Modification (6-1) Modification 1A
In the said embodiment, it has shown about the case where several indoor unit 12a, 12b is connected to the one outdoor unit 11. FIG. However, the present invention is not limited to such a configuration, and one indoor unit 12 a may be connected to one outdoor unit 11. Further, even when a plurality of indoor units 12a, 12b and outdoor units 11 are connected, the number of units to be connected can be arbitrarily determined according to the capabilities of the outdoor units 11 and indoor units 12a, 12b.

(6-2) Modification 1B
In the above embodiment, the case where the plurality of indoor units 12a and 12b have the same configuration has been described. However, if the configuration is not the same, the present invention does not hold, and the plurality of indoor units 12a, 12b, The configuration of 12b may be different from each other.

(6-3) Modification 1C
In the above embodiment, the case of maintaining the degree of superheat and supercooling in the indoor heat exchangers 22a and 22b has been described. However, even when the degree of superheat and subcooling is slightly changed, capacity control based on the air volume is mainly used. If there is, the same effect can be expected.

DESCRIPTION OF SYMBOLS 10 Air conditioning apparatus 11 Outdoor unit 12a, 12b Indoor unit 18 Control part 18b Memory 18c Timer 22a, 22b Indoor heat exchanger 23a, 23b Indoor fan 27a, 27b Indoor temperature sensor

JP-A-57-77218

Claims (7)

Fans (23a, 23b) for blowing conditioned air;
A temperature sensor (27a, 27b) for detecting a space temperature of a space cooled or heated by the conditioned air blown out by the fan;
When the temperature difference between the space temperature detected by the temperature sensor and the set temperature becomes small, the air volume of the fan is decreased to reduce the cooling capacity or the heating capacity, and within the set time after the fan air volume is decreased. A controller that performs automatic temperature control to increase the cooling capacity or heating capacity by increasing the air volume of the fan when the decrease in the temperature difference is less than a first set value;
An air conditioner comprising: The control unit obtains a decreasing tendency of the temperature difference near the time point when the temperature sensor detects that the space temperature has reached a set temperature, and matches the load estimated from the decreasing tendency of the temperature difference. Adjust the setting value,
The air conditioning apparatus according to claim 1. A heat exchanger (22a, 22b) for generating conditioned air by performing heat exchange between the air blown by the fan and the refrigerant;
The control unit performs control such that the degree of superheat or the degree of supercooling of the refrigerant in the heat exchanger is constant when the air volume of the fan is automatically controlled.
The air conditioning apparatus according to claim 1 or 2.   The control unit is provided with at least two zones of a first temperature range close to zero with respect to the temperature difference and a second temperature range farther away from zero than the first temperature range, and the temperature is included in the first temperature range. The first set value when a difference enters is set to be larger than the first set value when the temperature difference enters the second temperature range. Air conditioner.   The control unit is provided with a second set value smaller than the first set value in the first temperature range, and the second set value is less than the first set value even if the decrease in the temperature difference within the set time is smaller than the first set value. The air conditioner according to claim 4, wherein when it is larger than a set value, automatic temperature control is performed so as to maintain the current air flow of the fan. A temperature detection step (S28) for detecting the space temperature of the space where the conditioned air is blown by the fans (23a, 23b);
A first air volume control step (S35) for reducing the air volume of the fan in accordance with a decrease in the temperature difference between the space temperature and the set temperature according to the detection result of the temperature detection process;
A temperature difference decrease value acquisition step (S29) for obtaining a decrease value of the temperature difference within the set time for the temperature difference near the detection time point of the temperature detection step within a set time after the first air volume control step; ,
A second air volume control step (S33, S36) for increasing the air volume of the fan when the decrease value of the temperature difference acquired in the temperature difference decrease value acquisition process is below a set value;
The control method of an air conditioning apparatus provided with this. The second air volume control step obtains a decreasing tendency of the temperature difference near the time point when it is detected that the space temperature has reached the set temperature, and sets the set value according to a load estimated from the decreasing tendency of the temperature difference. Including a set value adjustment step (S66, S67) to be adjusted,
The control method of the air conditioning apparatus of Claim 6.

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