JP2008249286A - Multi-chamber type air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that, in a conventional multi-chamber type air conditioner, a relatively expensive pressure detector is used as a capacity control input of a compressor and excessive heating is effected under low load because a pressure setting value is determined according to the operation-on horsepower irrespective of the load of an indoor unit. <P>SOLUTION: The condensation temperature of refrigerating cycle can be detected at the maximum temperature value of an indoor heat exchanger in the connected indoor unit even without using the pressure detector. The heating performance can be ensured by correcting the frequency of the compressor upward until the target value is reached, when the condensation temperature is lower than a specified target condensation temperature threshold value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a compressor control method for a multi-room air conditioner in which a plurality of indoor units are connected to one outdoor unit to constitute a cooling or heating cycle.

  Conventionally, the compression function force control of this type of multi-chamber air conditioner uses the outside air temperature, pipe length, and operating horsepower as control inputs, and detects the high-pressure side pressure with a pressure detector and the pressure difference calculator. Some have calculated the differential pressure between the pressure and the set pressure, and determined the compression function force according to the calculated differential pressure (see, for example, Patent Document 1).

The flowchart of FIG. 7 shows a conventional multi-room air conditioner described in Patent Document 1. As shown in FIG. 7, the capacity control determining means 107 of the compressor 108 determines the set pressure by the set pressure detector 104 using the outside air temperature detector 101, the pipe length detector 102, and the operating horsepower number detector 103 as control inputs. The pressure difference with the pressure detector 105 is determined by calculating with the pressure difference calculator 106.
Japanese Patent Laid-Open No. 4-187930

  However, in the conventional configuration, a pressure detector having a high component unit price is used as the capacity control input of the compressor. Further, since the pressure set value is determined by the operation on horsepower number regardless of the load of the indoor unit, there is a problem that overheating occurs at a low load.

  The present invention solves the above-mentioned conventional problem, determines the fundamental frequency of the compressor according to the capability rank of the thermo-on indoor unit during heating operation, and sets the indoor heat exchanger temperature of all indoor units connected during heating operation. If the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensing temperature threshold, the frequency is corrected until the condensing temperature reaches the certain threshold. An object of the present invention is to provide a multi-room air conditioner capable of detecting the condensing temperature of the refrigeration cycle and ensuring the heating performance without using an expensive pressure detector.

  In order to solve the above-described conventional problems, a multi-room air conditioner of the present invention includes a single outdoor unit having a variable capacity compressor, a four-way valve, an outdoor heat exchanger, and an outdoor expansion valve, and an indoor heat exchange. In a multi-room air conditioner in which a plurality of indoor units having a heater and a temperature detecting means of the indoor heat exchanger are connected, the basics of the compressor according to the capability rank of the thermo-on indoor unit during heating operation Determine the frequency, detect the indoor heat exchanger temperature of all connected indoor units during heating operation, and if the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensing temperature threshold, the condensing temperature The frequency is corrected to increase until the value reaches a certain threshold value.

  As a result, the condensing temperature of the refrigeration cycle can be detected at the maximum indoor heat exchanger temperature in the connected indoor unit without using an expensive pressure detector, and the target condensing temperature is constant. When the temperature is lower than the threshold value, the heating performance can be ensured at the target condensing temperature by correcting the frequency to increase until the condensing temperature reaches a certain threshold value.

The multi-room air conditioner of the present invention determines the basic frequency of the compressor according to the capability rank of the thermo-on indoor unit during heating operation, detects the indoor heat exchanger temperature of all indoor units connected during heating operation, When the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensing temperature threshold, the unit price is high by correcting the frequency until the condensing temperature reaches the certain threshold. Without using a simple pressure detector, the condensation temperature of the refrigeration cycle can be detected to ensure heating performance.

  A multi-room air conditioner according to a first aspect of the present invention includes a single outdoor unit having a variable capacity compressor, a four-way valve, an outdoor heat exchanger, and an outdoor expansion valve, an indoor heat exchanger, and the indoor heat exchanger. In a multi-room air conditioner connected to a plurality of indoor units having temperature detection means, the basic frequency of the compressor is determined according to the capability rank of the thermo-on indoor unit during heating operation, and during heating operation When the indoor heat exchanger temperature of all connected indoor units is detected and the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensation temperature threshold, the condensation temperature reaches the certain threshold. Up to, the frequency is corrected to be increased.

  As a result, the condensing temperature of the refrigeration cycle can be detected at the maximum indoor heat exchanger temperature in the connected indoor unit without using an expensive pressure detector, and the target condensing temperature is constant. When the temperature is lower than the threshold value, the heating performance can be ensured at the target condensing temperature by correcting the frequency to increase until the condensing temperature reaches a certain threshold value.

  According to a second aspect of the present invention, in the multi-room air conditioner, when the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensation temperature threshold, the condensation temperature reaches a certain threshold. Up to this point, the frequency is corrected at a certain rate. As a result, the frequency can be reliably corrected to increase, and the heating performance can be ensured at the target condensation temperature.

  According to a third aspect of the present invention, in the multi-room air conditioner, when the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensation temperature threshold, the condensation temperature reaches a certain threshold. Up to this point, when the frequency is corrected to be increased, the first increase correction is larger than the second and subsequent correction values. This makes it possible to adjust the condensation temperature of the refrigeration cycle to the target condensation temperature quickly and without overshooting by ensuring that the frequency increase correction is large at the first time and smaller than the first time correction after the second time, ensuring heating performance. be able to.

  According to a fourth aspect of the present invention, in the multi-room air conditioner, when the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensation temperature threshold, the condensation temperature reaches a certain threshold. Until the frequency is corrected, the correction value is determined from the difference between the maximum indoor heat exchanger temperature in all the connected indoor units and a constant target condensing temperature threshold. This makes it possible to determine the frequency increase correction based on the temperature difference from the target condensation temperature, and to quickly adjust the condensation temperature of the refrigeration cycle to the target condensation temperature without overshooting. Can be secured.

  A fifth aspect of the invention is a multi-room air conditioner having a plurality of indoor units connected to each other having a temperature difference calculating means between the indoor intake air temperature and the indoor unit remote controller set temperature. Even if the chamber temperature is lower than a certain target condensing temperature threshold, if there is an indoor unit with a low temperature difference between the indoor intake air temperature and the indoor unit remote controller set temperature, the frequency is not increased and corrected. It is. As a result, the heating load required by the user can be detected from the difference between the indoor intake air temperature and the indoor unit remote controller set temperature, and the maximum indoor heat exchanger temperature in all connected indoor units can be detected when the required load is low and the load is low. Even when the temperature is lower than a certain target condensing temperature threshold, it is possible to suppress overheating without increasing the frequency.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a multi-room air conditioner according to an embodiment of the present invention. In FIG. 1, an indoor heat exchanger 6a, 6b, 6c (hereinafter, a plurality of units) is provided for one outdoor unit 5 having a variable capacity compressor 1, a four-way valve 2, an outdoor heat exchanger 3, and an outdoor expansion valve 4. In a multi-room type air conditioner to which a plurality of indoor units 8n having indoor heat exchanger temperature detecting means 7n are connected, and a indoor heat exchanger temperature detecting means 7n. When the machine 1 is operated, the indoor unit 8n becomes a condenser by switching the four-way valve 2 to dissipate heat for heating, and the outdoor expansion valve 4 depressurizes and the outdoor heat exchanger 3 becomes an evaporator to absorb heat from the outside air and perform a refrigeration cycle. It is composed. At this time, the maximum temperature of the indoor heat exchanger temperature detecting means 7n is recognized as the condensation temperature of the refrigeration cycle.

  FIG. 2 is a flowchart of the multi-room air conditioner in the first embodiment. The operation and action of the multi-room air conditioner according to the first embodiment of the present invention will be described with reference to FIG.

  In the heating operation compression functional force control (STEP 0), the outdoor unit 5 recognizes the operation stop state of the plurality of indoor units 8n, and receives the indoor functional force rank stored in the operating indoor unit 8n (STEP 1). The outdoor unit 5 determines and recognizes the basic frequency based on a comparison table between the indoor functional force rank stored in the indoor unit 5 and the compressor operating frequency or a predetermined arithmetic expression (STEP 2). Next, the maximum temperature in the indoor unit heat exchanger temperature detected by the connected all indoor unit heat exchanger temperature detecting means (STEP 3) is calculated by the connected all indoor unit heat exchanger temperature maximum value calculating means (STEP 4), and the calculated indoor The maximum temperature in the machine heat exchanger temperature is compared with the target condensing temperature, and a condensing temperature determination (STEP 5) is made as to whether it is less than the target condensing temperature.

  Here, when the temperature is equal to or higher than the target condensation temperature (No in STEP 5), the compressor operating frequency is determined (STEP 7) based on the value determined and recognized (STEP 2), and the indoor functional force rank is received (STEP 1). Transition. When the temperature is lower than the target condensation temperature (STEP 5 Yes), the frequency is increased (STEP 6), the compressor operating frequency is determined (STEP 7), and the indoor functional force rank is received (STEP 1).

From the above, it is possible to detect the condensing temperature of the refrigeration cycle at the maximum value of the indoor heat exchanger temperature in the connected indoor unit without using a pressure detector with an expensive part price, and the target condensing temperature is constant. When the temperature is lower than the temperature threshold, the heating performance can be ensured at the target condensing temperature by correcting the frequency to be increased until the condensing temperature reaches a certain threshold (Embodiment 2).
FIG. 3 is a flowchart of the multi-room air conditioner according to the second embodiment of the present invention. In FIG. 3, the same components as those in FIG. The operation and action of the multi-room air conditioner in the second embodiment of the present invention will be described with reference to FIG.

  The maximum temperature in the indoor unit heat exchanger temperature detected by the connected all indoor unit heat exchanger temperature detecting means (STEP 3) is calculated by the connected all indoor unit heat exchanger temperature maximum value calculating means (STEP 4), and the calculated indoor unit heat The maximum temperature in the exchanger temperature is compared with the target condensing temperature, and a condensing temperature determination (STEP 5) is performed to determine whether the temperature is lower than the target condensing temperature. When the temperature is equal to or higher than the target condensing temperature (NO in STEP 5), the compressor operating frequency is determined (STEP 17) based on the value determined and recognized (STEP 2), and the indoor functional force rank is shifted to receiving (STEP 1). When the temperature is lower than the target condensing temperature (STEP 5: Yes), the frequency is corrected at a fixed rate (STEP 16), the compressor operating frequency is determined (STEP 17), and the indoor functional force rank is received (STEP 1).

  From the above, the frequency can be reliably corrected to increase, and the heating performance can be ensured at the target condensation temperature.

(Embodiment 3)
FIG. 4 is a flowchart of the multi-room air conditioner according to the third embodiment of the present invention. 4, the same components as those in FIGS. 2 and 3 are denoted by the same reference numerals, and the description thereof is omitted. The operation and action of the multi-room air conditioner in the third embodiment of the present invention will be described with reference to FIG.

  The maximum temperature in the indoor unit heat exchanger temperature detected by the connected all indoor unit heat exchanger temperature detecting means (STEP 3) is calculated by the connected all indoor unit heat exchanger temperature maximum value calculating means (STEP 4), and the calculated indoor unit heat The maximum temperature in the exchanger temperature is compared with the target condensing temperature, and a condensing temperature determination (STEP 5) is performed to determine whether the temperature is lower than the target condensing temperature. When the temperature is equal to or higher than the target condensing temperature (NO in STEP 5), the compressor operating frequency is determined (STEP 29) based on the value determined and recognized (STEP 2), and the indoor functional force rank is shifted to receiving (STEP 1).

  Here, when the temperature is lower than the target condensation temperature (STEP 5 Yes), it is determined whether the frequency increase correction is the first time (STEP 26). When the increase correction is the first time (STEP 26 Yes), the first frequency increase correction (STEP 27). ), The compressor operating frequency is determined (STEP 29), and the indoor functional force rank is shifted to reception (STEP 1). When the increase correction is not the first time (No in STEP 26), the frequency increase correction (STEP 28) less than the initial frequency increase correction (STEP 27) is performed, the compressor operating frequency is determined (STEP 29), and the indoor functional force rank is received (STEP 1). ).

  From the above, it is possible to adjust the condensing temperature of the refrigeration cycle to the target condensing temperature quickly and without overshooting by increasing the frequency increase correction first time and making it smaller than the first correction after the second time. Can be secured.

(Embodiment 4)
FIG. 5 is a flowchart of the multi-room air conditioner according to the fourth embodiment of the present invention. In FIG. 5, the same components as those in FIGS. The operation and action of the multi-room air conditioner in the fourth embodiment of the present invention will be described with reference to FIG.

  The maximum temperature in the indoor unit heat exchanger temperature detected by the connected all indoor unit heat exchanger temperature detecting means (STEP 3) is calculated by the connected all indoor unit heat exchanger temperature maximum value calculating means (STEP 4), and the calculated indoor unit heat The maximum temperature in the exchanger temperature is compared with the target condensing temperature, and a condensing temperature determination (STEP 5) is performed to determine whether the temperature is lower than the target condensing temperature. When the temperature is equal to or higher than the target condensing temperature (NO in STEP 5), the compressor operating frequency is determined (STEP 29) based on the value determined and recognized (STEP 2), and the indoor functional force rank is shifted to receiving (STEP 1). When the temperature is lower than the target condensation temperature (STEP5: Yes), the difference between the condensation temperature of the refrigeration cycle and the target condensation temperature is recognized by the maximum value of the indoor heat exchanger and the target condensation temperature difference temperature calculation means (STEP36). For example, it is determined whether or not the temperature difference temperature is 5K or more (STEP 37). If the target condensation temperature difference temperature is 5K or more (Yes in STEP 37), frequency increase correction (STEP 38) is performed when the temperature difference is 5K or more. When the temperature difference temperature is less than 5K (No in STEP 37), the frequency increase correction (STEP 39) is set to be equal to or less than the frequency increase correction (STEP 38) when the difference temperature is 5K or more, and the compressor operating frequency is determined (STEP 40). The function power rank is shifted to reception (STEP 1).

  From the above, the frequency increase correction can be determined by the temperature difference from the target condensation temperature, and the condensation temperature of the refrigeration cycle can be adjusted quickly and without overshooting to the target condensation temperature. Heating performance can be ensured.

(Embodiment 5)
FIG. 6 is a flowchart of the multi-room air conditioner according to the fifth embodiment of the present invention. In FIG. 6, the same components as those in FIGS. 2, 3, 4, and 5 are denoted by the same reference numerals and description thereof is omitted. The operation and action of the multi-room air conditioner in the fifth embodiment of the present invention will be described with reference to FIG.

  In the heating operation compression functional force control (STEP 0), the outdoor unit 5 recognizes the operation stop state of the plurality of indoor units 8n, and receives the indoor functional force rank stored in the operating indoor unit 8n (STEP 1). The outdoor unit 5 determines and recognizes the basic frequency based on a comparison table between the indoor functional force rank stored in the indoor unit 5 and the compressor operating frequency or a predetermined arithmetic expression (STEP 2). Each indoor unit intake air temperature and the remote controller set temperature difference temperature calculation means (STEP 41) grasp the heating load state of each indoor unit, and the heating load determination (STEP 42) determines the indoor unit intake air temperature and the remote controller set temperature difference temperature, For example, when there is an indoor unit of 1K or less (NO in STEP42), the compressor operating frequency is determined (STEP7) based on the value determined and recognized (STEP2), and the indoor unit intake air temperature and the remote controller set temperature are determined. For example, when there is no indoor unit having a temperature difference of 1K or less (YES in STEP 42), the maximum temperature among the indoor unit heat exchanger temperatures detected by the connected all indoor unit heat exchanger temperature detection means (STEP 3) It is calculated by the maximum heat exchanger temperature calculation means (STEP 4), and the target indoor temperature is calculated by comparing the maximum indoor heat exchanger temperature with the target condensation temperature. Condensation temperature lower than if the condensing temperature determined (STEP5) performed.

  Here, when the temperature is equal to or higher than the target condensation temperature (No in STEP 5), the compressor operating frequency is determined (STEP 7) based on the value determined and recognized (STEP 2), and the indoor functional force rank is received (STEP 1). Transition. When the temperature is lower than the target condensing temperature (STEP5: Yes), the frequency is increased (STEP6), the compressor operating frequency is determined (STEP7), and the indoor functional force rank is received (STEP1).

  Based on the above, it is possible to detect the heating load requested by the user based on the difference between the indoor intake air temperature and the indoor unit remote controller set temperature. When the required load is low, the maximum indoor heat exchange among all connected indoor units Even when the chamber temperature is lower than a certain target condensing temperature threshold, it is possible to suppress excessive heating without increasing the frequency.

  As described above, the multi-room air conditioner according to the present invention detects the condensing temperature of the refrigeration cycle at the highest indoor heat exchanger temperature in the connected indoor unit without using a pressure detector with an expensive part price. If the condensing temperature is lower than a certain target condensing temperature threshold, heating performance is ensured at the target condensing temperature by correcting the frequency until the condensing temperature reaches the certain threshold. Therefore, it can be applied to a heat storage type multi-room type air conditioner.

Configuration schematic diagram of a multi-room air conditioner in an embodiment of the present invention Flowchart of the multi-room air conditioner in Embodiment 1 of the present invention Flowchart of multi-room air conditioner in Embodiment 2 of the present invention Flow chart of multi-room air conditioner in Embodiment 3 of the present invention The flowchart of the multi-room air conditioner in Embodiment 4 of this invention Flow chart of multi-room air conditioner in Embodiment 5 of the present invention Conventional multi-room air conditioner flowchart

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Capability variable compressor 2 Four-way valve 3 Outdoor heat exchanger 4 Outdoor expansion valve 5 Outdoor unit 6n Indoor heat exchanger 7n Indoor heat exchanger temperature detection means 8n Indoor unit STEP0 Heating operation compression functional force control STEP1 Receives indoor functional force rank STEP 2 Basic frequency determination recognition STEP 3 Connected all indoor unit heat exchanger temperature detection means STEP 4 Connected all indoor unit heat exchanger temperature maximum value calculation means STEP 5 Condensation temperature determination STEP 6 Frequency increase correction STEP 7 Compressor operating frequency determination

Claims (5)

One outdoor unit having a variable capacity compressor, a four-way valve, an outdoor heat exchanger, and an outdoor expansion valve, and a plurality of indoor units having an indoor heat exchanger and temperature detecting means of the indoor heat exchanger. In the connected multi-room air conditioner, the basic frequency of the compressor is determined according to the capacity rank of the thermo-on indoor unit during heating operation, and the indoor heat exchanger temperature of all the indoor units connected during heating operation is detected. When the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensation temperature threshold, the frequency is corrected to increase until the condensation temperature reaches the certain threshold. Room type air conditioner. When the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensing temperature threshold value, the frequency is corrected to increase by a certain ratio until the condensing temperature reaches the certain threshold value. The multi-room air conditioner according to claim 1. When the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensing temperature threshold, when the frequency is corrected to increase until the condensing temperature reaches the certain threshold, the first increase correction is performed. The multi-room air conditioner according to claim 1, wherein the multi-room air conditioner is larger than a correction value after the second time. When the maximum indoor heat exchanger temperature in all connected indoor units is lower than a certain target condensing temperature threshold, when the frequency is corrected to increase until the condensing temperature reaches the certain threshold, all connected indoor units The multi-room air conditioner according to claim 1, wherein the correction value is determined from a difference temperature between the maximum indoor heat exchanger temperature and a constant target condensation temperature threshold value. In a multi-room air conditioner connected to multiple indoor units that have a means for calculating the difference between the indoor intake air temperature and the indoor unit remote controller set temperature, the maximum indoor heat exchanger temperature in all connected indoor units is constant. The frequency is not corrected to be increased when there is an indoor unit having a low differential temperature between the indoor intake air temperature and the indoor unit remote controller set temperature even when the temperature is lower than a target condensation temperature threshold. Room type air conditioner.