JP2011202845A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such problems that development cost is required since predetermined defrosting time data exclusive for hot gas bypass defrosting is necessary; sequences of four-way valve switching defrosting and defrosting operation are different, piping temperature correction can not be applied to the hot gas bypass defrosting in control of present piping temperature correction, and control capable of carrying out piping temperature correction is also necessary in hot gas bypass defrosting; and accordingly, it is necessary to separate control and data of piping temperature control during four-way valve switching defrosting and piping temperature correction during hot gas bypass defrosting.SOLUTION: A control system is a control system capable of corresponding by the same control even in systems with different defrosting times and control sequences in piping temperature correction control.

Description

  The present invention relates to an air conditioner or the like capable of performing a defrosting operation for removing frost attached to an outdoor heat exchanger while heating is continued during a heating operation by a heat pump operation.

  Conventionally, this type of heat pump type air conditioner defrosting method generally employs a defrosting method in which the four-way valve is switched and the refrigerant in the refrigeration cycle flows in the reverse direction. That is, in the defrosting operation, the frost adhering to the outdoor heat exchanger is melted by flowing the high-temperature and high-pressure refrigerant through the outdoor heat exchanger with the same refrigerant flow direction as that during cooling.

  In this defrosting method, during the defrosting, since the indoor heat exchanger becomes an evaporator, there is a basic problem that the temperature of the room is lowered and a cold wind feeling is felt. As a countermeasure against this basic problem, an air conditioner that performs a defrosting operation while continuing the heating operation has been proposed (for example, see Patent Document 1).

  As shown in FIG. 3, the air conditioner of Patent Document 1 includes a compressor 1, a four-way valve 2, a decompressor 4, an outdoor fan 17, an outdoor heat exchanger 5, and an outdoor pipe temperature that detects the temperature of the outdoor heat exchanger 5. The outdoor unit 19 provided with the detection means 22, the outdoor air temperature detection means 20 for detecting the outdoor air temperature, the indoor heat exchanger 3, the indoor blower 16, and the indoor air temperature detection means 21 for detecting the indoor air temperature. A heat pump refrigeration cycle in which a machine 18 is connected by a refrigerant circuit 11, a first two-way valve 7 and a refrigerant heater 9, and between the indoor heat exchanger 3 and the pressure reducer 4, and the four-way valve 2 While having the 1st bypass circuit 6 which connects between the said outdoor heat exchangers 5, and the 2nd two-way valve 14, between the said four-way valve 2 and the said indoor heat exchanger 3, or the said compressor 1 and the said Between the four-way valve 2 and between the pressure reducer 4 and the outdoor heat exchanger 5 And a second bypass circuit 13 connecting.

  When the defrosting of the outdoor heat exchanger 5 is performed, the first two-way valve 7 is opened to allow the refrigerant heated by the refrigerant heater 9 to flow to the suction side of the compressor 1. In an air conditioner that performs defrosting by bypass gas operation and hot gas bypass in the second bypass operation in which the second two-way valve 14 is opened and the refrigerant passes through the outdoor heat exchanger 5. If the temperature of the outdoor heat exchanger detected by the outdoor pipe temperature detecting means within the first predetermined time does not reach the predetermined temperature, the defrosting operation by the hot gas bypass is terminated, and the second predetermined Four-way valve switching defrosting is performed in which the refrigerant circuit is switched by the four-way valve 2 and the defrosting is performed by the operation of the cooling cycle after performing the heating operation during the time and during the defrosting.

  As a result, the defrosting operation can be performed while performing the heating operation, and the defrosting method performed by the hot gas bypass and the four-way valve switching defrosting that performs the defrosting by the operation of the cooling cycle are not continuously operated. Although there is a small decrease in room temperature due to gas bypass defrosting, it is switched to heating operation during defrosting and the room temperature is restored, and then switching to four-way valve switching defrosting, so comfort does not deteriorate. . In addition, heating during defrosting is operated for the second predetermined time, but since it is after hot gas bypass defrosting, the amount of frost formation before starting the four-way valve switching defrosting is small, and the four-way valve switching defrosting time becomes long. In addition, there is little decrease in room temperature and comfort does not deteriorate.

Further, in the case of defrosting by switching the four-way valve, after the defrosting operation, the outdoor pipe temperature threshold when the next defrosting operation is started is corrected by the ratio of the defrosting operation time and the heating operation time shown in FIG. The time interval for entering the next defrosting operation is changed according to the amount. Actually, the start of defrosting is determined based on the outdoor unit piping temperature, but the time to enter the next defrosting operation is changed by correcting the determination threshold.

JP 2009-47344 A

  Currently, in the case of four-way valve switching defrosting, by correcting the defrosting start temperature of the outdoor unit piping temperature, which is the condition for starting the next defrosting, at the ratio of each defrosting time and the heating operation time after the defrosting, Appropriate defrosting can be performed according to the amount of defrosting. (Hereinafter referred to as piping temperature correction.) However, since predetermined defrosting time data dedicated to hot gas bypass defrosting is required and the four-way valve switching defrosting and defrosting operation sequences differ, FIG. The desired defrosting end time is used for pipe temperature correction, but the current pipe temperature correction control can be applied only by the defrosting time shown in FIG. 4, and pipe temperature correction cannot be applied in hot gas bypass defrosting. For this reason, the control which can implement piping temperature correction | amendment also for hot gas bypass defrosting is needed. In addition, since pipe temperature correction is performed every time after each defrost operation, when defrosting is performed multiple times continuously, the pipe temperature is determined by the defrosting time during the last defrost operation that is repeated multiple times. Since the correction is performed, the piping temperature cannot be corrected by the defrosting operation time at the first time that is continuously performed a plurality of times.

  Therefore, it is necessary to separate the control and data of the piping temperature correction at the time of defrosting the four-way valve switching and the piping temperature correction at the time of hot gas bypass defrosting.

  In order to solve the above-described conventional problems, the control method of the present invention is a control method that can handle pipe temperature correction control with the same control even if the defrosting time and the control sequence are different.

  The control method of the present invention is a control method that can cope with pipe temperature correction control with the same control even if the defrosting time and the control sequence are different. Therefore, the hot gas bypass defrosting is performed by one electronic control unit. It is possible to perform defrost control that can be switched between the presence / absence of control, and the effect of lowering the development cost is achieved.

Block diagram of the electronic control device according to the first and second embodiments of the present invention Operation flow chart of piping temperature correction control in Embodiment 1 of the present invention Configuration diagram of a refrigeration cycle common to Embodiments 1 and 2 of the present invention and a conventional air conditioner The relationship diagram of acquisition defrost time of piping temperature correction control common to Embodiment 1, 2 of this invention, and the conventional air conditioner Relationship diagram of acquisition defrost time of pipe temperature correction control in Embodiment 2 of the present invention

  1st invention can perform piping temperature correction by the same control also in the case of each different defrost time and sequence also in the case of four-way valve switching defrost and hot gas bypass defrost control of heat pump type electric equipment. In the possible defrost control, the above can be selected depending on the electric equipment to be used, and the development cost can be reduced without being influenced by the specifications of the defrost control to be used.

  According to the second aspect of the present invention, by switching the defrosting control, one can be continuously shifted to a plurality of types of defrosting, while the other can be selected not to continuously shift to a plurality of types of defrosting, The air conditioner used for the defrost control to be used is provided, and the development cost can be reduced without being influenced by the specifications of the defrost control to be used.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram according to the first embodiment of the present invention. Reference numeral 24 denotes defrost control means, 25 denotes defrost start determination means, 26 denotes defrost control switching means, and 23 denotes hot gas bypass defrost control means.

  The defrost control 8 means 24 determines whether or not the defrost control start condition is satisfied by the defrost start determination means 25, and if the defrost control start condition is satisfied, the defrost control switching means 26 removes the defrost control start condition. Select the type of frost control.

  The type of defrosting is selected by the defrosting control switching means 26, a predetermined defrosting operation time according to the type of defrosting, a frequency command for the compressor operating means 27, and an expansion for the expansion valve opening varying means 28. A defrosting operation is performed by giving a valve opening command, an outdoor fan speed command to the outdoor fan operating means 29, and a switching command to the four-way valve switching means 30.

  The hot gas bypass defrosting control means 23 includes a heater heater on / off command to the refrigerant heater control means 32 and a refrigerant heating two-way valve to the refrigerant heating two-way valve opening / closing means 33 for a predetermined time for hot gas bypass defrosting. The defrosting method can be switched by enabling the defrosting two-way valve opening / closing means 34 and the defrosting two-way valve opening / closing command 34 and the outdoor heat exchanger temperature detecting means 35.

  In the case of a heat pump type electric device having a hot gas bypass circuit, hot gas bypass defrost control is performed by selecting the presence of hot gas bypass defrost control. In the case of heat pump type electrical equipment that does not have a hot gas bypass circuit, by selecting no hot gas bypass defrosting control, defrosting control without using hot gas bypass is performed, so pipe temperature correction that differs depending on the defrosting control method In the case of pipe temperature correction using the defrosting time shown in FIG. 2, the defrosting time is acquired, and the defrosting time shown in FIG. In the case of correction of the piping temperature to be used, when the switching of the hot gas bypass defrosting control is realized with one type of electronic control device by acquiring the defrosting end time, the predetermined piping temperature is determined according to the defrosting method. Correction can be performed.

(Embodiment 2)
FIG. 2 is a flowchart according to the second embodiment of the present invention, and since the configuration is the same as that of the first embodiment, description thereof is omitted.

  By switching defrost control in the first embodiment of the present invention, one is continuously shifted to a plurality of types of defrost, but one is not continuously shifted to a plurality of types of defrost. Is possible.

  In FIG. 2, after the defrost start condition is established in STEP 001, when it is determined that the hot gas bypass defrost is determined in the hot gas bypass defrost determination in STEP 002, the hot gas bypass defrost operation is performed in STEP 003.

After completion of the hot gas bypass defrosting operation in STEP003, the defrosting end determination is performed in STEP004. If the defrosting end determination is satisfied, the defrosting control is ended, and the normal heating operation is performed in STEP009. If the defrosting end determination is not satisfied in the defrosting end determination STEP004, the hot gas bypass defrosting operation is performed in STEP005.

  After completion of the hot gas bypass defrosting in STEP005, the defrosting end determination is performed in STEP006. If the defrosting end determination is satisfied, the defrosting control is ended, and the normal heating operation is performed in STEP009. If the defrosting end determination is not satisfied in STEP006, the heating operation is performed for a predetermined time in the inter-frost heating operation in STEP007, and the four-way valve switching defrosting is started in STEP008 after the predetermined time has elapsed.

  When it is determined that the hot gas bypass defrosting is not performed in STEP002, the four-way valve switching defrosting operation is performed in STEP010. After the four-way valve switching defrosting operation is completed, the normal heating operation in STEP011 is performed.

  When performing the hot gas bypass defrosting operation or the four-way valve switching defrosting operation again after the hot gas bypass defrosting operation is completed, the piping temperature correction acquires the defrosting time of the first defrosting operation at the time of continuous as shown in FIG. Thus, pipe temperature correction can be performed, and predetermined pipe temperature correction can be performed.

  As described above, the control method of the present invention can cope with each defrosting time and different sequences regardless of whether the four-way valve switching defrosting or the hot gas bypass defrosting is selected, so that the outdoor temperature is very low. The piping temperature is corrected by an electronic control unit that is shared with the general public and those that do not require hot gas bypass defrosting, so that the defrosting operation can be performed appropriately, so it can be removed using a heat pump such as an air conditioner or a water heater. It can be widely applied to the use of electric equipment that performs frosting.

23 Degassing control means 24 Defrosting control means 25 Defrosting start determining means 26 Defrosting control switching means 27 Compressor operating means during defrosting operation 28 Expansion valve opening varying means during defrosting operation 29 During defrosting operation Outdoor fan operating means 30 Four-way valve switching means during defrosting operation 31 Outdoor air temperature detecting means 32 Refrigerant heater control means 33 Refrigerant heating two-way valve opening / closing means 34 Defrosting two-way valve opening / closing means 35 Outdoor heat exchanger temperature detection means

Claims (2)

In the case of the four-way valve switching defrosting and hot gas bypass defrosting control of the heat pump type electric equipment, it has a control method capable of correcting the pipe temperature by the same control even in each different defrosting time and sequence. Air conditioner. Even in the case of a single electronic control unit that uses multiple types of defrosting controls such as four-way valve defrosting and hot gas bypass defrosting control, a control method that can correct the pipe temperature according to each defrosting method An air conditioner characterized by comprising.

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