JP4510964B2 - Air conditioner control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dehumidifying operation when the room temperature or the outside air temperature is low in an air conditioner having a dehumidifying function.
[0002]
[Prior art]
Conventional air conditioners include those described in Japanese Patent Laid-Open No. 7-139848. In this refrigeration cycle, an indoor heat exchanger is cooled by evaporation in a refrigeration cycle configured using a compressor, an indoor heat exchanger, a decompression device (throttle device), and an outdoor heat exchanger. It is divided into a dehumidifying part and a heating part by condensation, and the heating capacity of the heating part and the release of the outdoor heat exchanger are controlled by controlling the air volume of the fan of the outdoor heat exchanger, the capacity of the compressor, and the air volume of the fan of the indoor heat exchanger. The amount of heat is controlled. By such control, when the room temperature is high, the dehumidifying operation with cooling can be performed, when the room temperature is almost equal to the set temperature, the dehumidifying operation with isothermal feeling can be performed, and when the room temperature is low, the dehumidifying operation with heating can be performed. It was a thing.
[0003]
[Problems to be solved by the invention]
In the conventional structure constructed as described above, since the emphasis is on the dehumidifying operation, the room temperature tends to decrease when the room temperature or the outside air temperature is low. In particular, when drying laundry etc. indoors, a drop in room temperature appears remarkably at the start of operation due to the humidity.
[0004]
In the case of a dehumidifying operation with a heating effect, the lowering of the room temperature finally returns after a long operation.
[0005]
The present invention provides a dehumidifying operation suitable for such problems when the room temperature or the outside air temperature is low.
[0006]
[Means for Solving the Problems]
The present invention has a refrigeration cycle in which a compressor, a heat source side heat exchanger, a decompression device, and a use side heat exchanger are connected in an annular shape using refrigerant piping, and at least the use side heat exchanger acts as a condenser to condense the condensation. A heating cycle for supplying air heated by the evaporator to the conditioned room, a cooling cycle for supplying the air cooled by the evaporator to the conditioned room by operating the usage side heat exchanger as an evaporator, and a usage side heat exchanger In a control apparatus for an air conditioner, in which a dehumidifying cycle is selected by which the air cooled by the evaporator is reheated after being divided into a part that acts as a condenser and a part that acts as an evaporator An automatic operation control unit that automatically selects at least one of the heating cycle, the cooling cycle, and the dehumidification cycle based on the environmental conditions of the conditioned room at the start of operation, and heating A heating operation by the vehicle, a cooling operation by the cooling cycle, a first dehumidifying operation by the dehumidifying cycle, and a second dehumidifying operation in which the target humidity is set lower than the first dehumidifying operation by the dehumidifying cycle, A controller that periodically switches between the dehumidification cycle and the heating cycle after starting the operation for a predetermined time in the heating operation when the cycle selected by the automatic operation control unit when the dehumidifying operation of 2 is selected is the heating cycle; It is provided.
[0011]
By providing such a control unit, a decrease in room temperature can be suppressed.
[0012]
Further, the control unit performs the dehumidifying operation by the dehumidifying cycle when the cycle selected by the automatic operation control unit is the cooling cycle or the dehumidifying cycle when the second dehumidifying operation is selected.
[0013]
By providing such a configuration, an increase in the room temperature can be suppressed when the room temperature is high.
[0014]
The automatic operation control further automatically selects at least one of a heating cycle, a cooling cycle, and a dehumidification cycle based on the outside air temperature.
[0015]
By providing such a configuration, it is possible to determine a period during which heating is required and to suppress a decrease in room temperature.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a refrigerant circuit diagram. In this figure, 1 is a variable operating capacity compressor, 2 is a four-way switching valve, 3 is an outdoor heat exchanger, 4a and 4b are arbitrarily controlled in accordance with a control signal. Electric expansion valve (pressure reduction device) that can be adjusted to 5, 5 is a strainer, 6 and 7 are indoor heat exchangers divided into two, 8 is an accumulator, and is connected in an annular shape with a refrigerant pipe as shown in the figure, and is a refrigeration cycle Is configured.
[0017]
The operating capacity of the compressor 1 is automatically controlled so as to reach a magnitude that balances the air conditioning load of the conditioned room (indoor) within a predetermined range. For example, the temperature deviation between the indoor temperature and the set temperature e and a change Δe of the temperature deviation e are obtained every predetermined period, and a fuzzy calculation is performed from the values of e and Δe to obtain a correction value of the driving ability. Next, there is a method of setting a value obtained by adding this correction value to the current operating capacity as a new operating capacity. However, the setting of the operating capacity of the compressor 1 is not limited to this method, and only from the temperature deviation e. Other methods such as obtaining may be used as long as the air conditioning load of the conditioned room is followed.
[0018]
The indoor heat exchangers 6 and 7 are connected in series via the electric expansion valve 4b. When the electric expansion valve 4b is in a fully open state, the indoor heat exchangers 6 and 7 are substantially integrated. is there.
[0019]
When the electric expansion valve 4a is fully opened and the throttle amount (pressure reduction amount) of the electric expansion valve 4b is adjusted, the indoor heat exchangers 6 and 7 are condensed and evaporated (or when the refrigerant circulation direction is reversed) And a dehumidifying operation can be performed.
[0020]
In addition, 9 and 10 are mufflers (silencers), 11 is a blower device (propeller fan) for the outdoor heat exchanger, and 12 is a blower device (cross flow fan) for the indoor heat exchanger. The blower 12 uses a DC brushless motor as a motor so that the amount of blown air can be varied substantially linearly.
[0021]
When the state of the four-way switching valve 2 is shown by a solid line (the state shown in the figure) and the electric expansion valve 4b is fully open, the high-temperature and high-pressure refrigerant discharged from the compressor 1 passes through the muffler 9 and the four-way switching valve 2. After condensing in the outdoor heat exchanger 3, evaporates in the indoor heat exchangers 6 and 7 through the electric expansion valve 4 a and the strainer 5, and then sucked into the compressor 1 again through the muffler 10, the four-way switching valve 2 and the accumulator 8. However, the cooling cycle indicated by the solid line arrow is circulated.
[0022]
At this time, the refrigerant evaporates in the indoor heat exchangers 6 and 7 to perform a cooling operation (cooling cycle), and the cooled air is supplied to the conditioned room by the blower 12.
[0023]
Further, at this time, by periodically increasing / decreasing the amount of air blown by the blower 12, the cooling effect for supplying the cool air to the conditioned room and the operation for reducing the supply of the cool air to almost the stop and interrupting the cooling effect are performed. While preventing the temperature rise of the conditioned room due to the operation, it is also possible to perform an operation that enables the dehumidification by the cooling operation without substantially lowering the room temperature.
[0024]
When the electric expansion valve 4a is fully opened, the blower 11 is stopped and the opening degree (throttle amount) of the electric expansion valve 4b is adjusted, the refrigerant discharged from the compressor 1 is condensed in the indoor heat exchanger 6, It evaporates with the indoor heat exchanger 7 (dehumidification cycle). Accordingly, the air heated by the indoor heat exchanger 6 by the blower 12 and the air cooled by the indoor heat exchanger 7 are mixed and supplied to the conditioned room, and therefore dehumidified by the indoor heat exchanger 7. At the same time, the throttle amount is controlled by the electric expansion valve 4b, and the air whose discharge air temperature is controlled is supplied to the conditioned room.
[0025]
In other words, the dehumidifying operation with cooling and the dehumidifying operation with warming can be performed by adjusting the throttle amount of the electric expansion valve 4b.
[0026]
In addition, by arranging the indoor side heat exchanger 7 and the indoor side heat exchanger 6 in order from the windward side in the same air passage, the air cooled by the indoor side heat exchanger 7 is transferred by the indoor side heat exchanger 6. The same dehumidifying effect can be obtained even if it is configured to be directly heated.
[0027]
When the four-way switching valve 2 is in the state indicated by the dotted line, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is condensed in the indoor heat exchangers 6 and 7 via the muffler 9, the four-way switching valve 2 and the muffler 10. Then, after evaporating in the outdoor heat exchanger 3 through the strainer 6 and the electric expansion valve 4a, it circulates through the heating cycle indicated by the dotted arrow where it is sucked into the compressor 1 again through the four-way switching valve 2 and the accumulator 8. .
[0028]
At this time, the refrigerant is condensed in the indoor heat exchangers 6 and 7 to perform heating operation, and the heated air is supplied to the conditioned room by the blower 12.
[0029]
FIG. 2 is a schematic block diagram of a control circuit provided in the indoor unit of the air conditioner (unit in which the indoor heat exchanges 6 and 7 are mounted).
[0030]
In this figure, reference numeral 21 denotes a plug to which 100V AC power is supplied, and is connected to a 100V commercial AC power supply. This AC power is supplied to the power supply circuit 23 via the switch 22.
[0031]
Reference numeral 24 is a current fuse, 25 is a rectifier circuit, 26 is a motor power supply, 27 is a control power supply, and 28 is a serial power supply. These components constitute the power supply circuit 23.
[0032]
The current fuse 24 is blown to protect the circuit when the current supplied to the power supply circuit 23 exceeds a predetermined current, and the rectifier circuit 25 converts the AC power obtained through the current fuse 24 into a full wave. The motor power supply circuit (switching power supply circuit) 26 generates a driving power supply for the fan motor (DC sensorless motor) 29 that constitutes the blower 12 and has a switching waveform based on a signal from a microcomputer to be described later. The output voltage is varied between DC12V and DC48V by controlling the ON duty.
[0033]
The control power supply 27 generates and stabilizes the drive power supply (DC5V) of the control unit 30, and the serial power supply 28 transmits a signal (four-way switching valve 2) to be transmitted to the outdoor unit (in which the outdoor heat exchanger 3 is mounted). The switching signal, the setting value of the operating capacity of the compressor 1, etc.) is a circuit for sharing the common line with the AC power supplied to the outdoor unit.
[0034]
Reference numeral 31 denotes a terminal plate. The first terminal, the second terminal, and the third terminal are provided on a resin-made terminal block, and a temperature fuse 32 that melts at a predetermined temperature or more and opens a circuit is provided on the terminal block. It is attached so that the temperature, that is, the temperature of the terminal board 31 can be detected.
[0035]
A normally open contact piece 37 of the power relay 36 is interposed between the first terminal of the terminal board 31 and the plug 21, and the normally open contact piece 37 is closed by the output of the microcomputer 33 (the driver is not shown). The AC power output from 31 to the outdoor unit is controlled.
[0036]
The second terminal of the terminal board 31 is connected to the plug 21 and is a common line with the third terminal (signal output terminal).
[0037]
The third terminal is a terminal for outputting a signal output from the microcomputer 33 via the serial circuit 28 a and the serial power supply 28.
[0038]
In addition, the 1st terminal-3rd terminal of the terminal board 31 is connected so that the same terminal number may connect with the terminal board of the electric circuit mounted in the outdoor unit of FIG. 3 mentioned later.
[0039]
The thermal fuse 32 is inserted into the drive line of the power relay 36, and when the temperature of the terminal board 31 rises, the power relay 36 is cut off and the normally open contact piece 37 is opened to supply AC power to the outdoor unit. It is a thing to cut off.
[0040]
Reference numeral 39 denotes a wireless remote controller, which performs various settings and function selections such as operation control of the air conditioner and setting of setting values based on the operation of the switch, and the operation signal is provided on the display board 40. Sent to the receiving circuit.
[0041]
The microcomputer 33 receives this operation signal and controls the operation of the air conditioner. The display board 40 displays the operation state of the air conditioner (operation mode such as cooling / heating / drying, set values, room temperature, etc.).
[0042]
Reference numeral 41 denotes a switch board, which is provided with switches for services such as the switch 22 and a test operation switch.
[0043]
An external ROM 42 stores an initial setting value of the microcomputer 33.
[0044]
Reference numerals 43 and 44 denote a temperature sensor for detecting the temperature of the room and a temperature sensor for detecting the temperature of the indoor heat exchanger 6, which are connected to an A / D input terminal of the microcomputer 33. The microcomputer 33 controls the operation of the air conditioner based on these detected temperatures.
[0045]
A humidity sensor 45 detects the humidity in the room and is connected to an A / D input terminal of the microcomputer 33. The microcomputer 33 controls the operation of the air conditioner based on the detected temperature and humidity.
[0046]
A step motor 46 changes the opening degree of the electric expansion valve 4b, and changes the opening degree of the electric expansion valve 4b in response to a signal from the microcomputer 33.
[0047]
A motor drive circuit 47 has an inverter circuit in which switching elements are connected in a three-phase bridge shape. When a DC sensorless motor is used, the output of this inverter circuit is matched with the rotational position of the rotor of the fan motor 29. It is to switch. A signal for switching the output of the inverter circuit is output by the microcomputer 33 judging from the rotational position of the rotor, and the rotational speed of the fan motor 29 is controlled by the voltage of the DC voltage output from the motor power supply 26.
[0048]
The electric expansion valves 4 a and 4 b are configured such that the refrigerant throttle amount is controlled by a built-in drive unit (step motor or the like), and the throttle amount is arbitrarily controlled according to a signal output from the microcomputer 33. Further, when one of the electric expansion valves 4a and 4b is a control target, the rest is fully opened. The electric expansion valves 4a and 4b are controlled so that the temperature of the heat exchanger acting as an evaporator becomes constant.
[0049]
FIG. 3 is a block diagram showing an outline of a control circuit mounted on the outdoor unit, and is connected to the terminal board 31 shown in FIG.
[0050]
In this figure, reference numeral 52 denotes a power circuit, which rectifies and smoothes 100V AC power from the indoor unit obtained through the first and second terminals of the terminal board 51 by double voltage rectification, and a varistor and noise filter. A reactor, a current fuse, etc. are added.
[0051]
The DC power output from the power supply circuit 52 is output to an inverter circuit 53 in which switching elements are connected in a three-phase bridge shape, and a three-phase alternating current of a pseudo sine wave based on the PWM theory (the compressor 1 uses an induction motor). Or after being converted to a system in which the stator winding is energized with the energization pattern corresponding to the rotation position (when the compressor 1 uses a DC brushless motor). , And supplied to the compressor 1.
[0052]
Accordingly, in any case, the operating speed of the compressor 1 can be controlled by changing the rotation speed of the compressor 1.
[0053]
Reference numeral 55 denotes a microcomputer, which forms the control unit 54. Based on the control signal received from the microcomputer 33 of the indoor unit via the third terminal of the terminal board 51 and the serial circuit 56, the microcomputer 55 controls the driving ability (the number of revolutions) of the compressor 1 by the above operation, and further switches four-way. Controls the switching of the valve 2 and the blower 11 (fan motor that drives the propeller fan), and compresses so that the current value detected by a CT (current detector) 58 connected to the current detection circuit 57 does not exceed a predetermined value. The operating capacity of the compressor 1 is controlled so that the temperature of a temperature sensor 59 that detects the temperature of the compressor 1 does not exceed a predetermined value.
[0054]
Reference numeral 60 denotes an outside air temperature sensor that detects the temperature of outside air. The outside air temperature detected by this sensor is transmitted to the microcomputer 33 of the indoor unit via the serial circuit 56.
[0055]
Note that 61 is a temperature sensor that detects the temperature of the outdoor heat exchanger, and 62 is a switching power supply that generates DC power for control.
[0056]
In the air conditioner configured as described above, the operation of each device is controlled based on a program stored in the microcomputer 33 of the indoor unit.
[0057]
FIG. 4 is a flowchart showing the driving operation according to the present invention, which is a subroutine branching from the main program stored in the microcomputer 33.
[0058]
In the main program, the heating cycle, the cooling cycle, and the dehumidification cycle are first set as the operation settings of the air conditioner. This setting is set in the table shown in FIG. 5 when “automatic operation” is selected. One of the heating cycle, the cooling cycle, and the dehumidification cycle is set based on the above.
[0059]
As shown in FIG. 5, this setting is based on the room temperature of the conditioned room (the temperature detected by the temperature sensor 43 or the room temperature transmitted from the remote control 39) and the outside temperature detected by the outside temperature sensor 60 of the outdoor unit. Selected. In FIG. 5, H indicates a heating cycle, D indicates a dehumidification cycle, and C indicates a cooling cycle.
[0060]
When “cooling operation” is selected, the cooling cycle is selected regardless of the table shown in FIG.
[0061]
When “dehumidification operation” (normal dehumidification and corresponds to the first dehumidification operation), “dehumidifier”, and “laundry” (corresponding to the second dehumidification operation) are selected, it relates to the table shown in FIG. Dehumidification cycle is selected.
[0062]
When the cooling cycle is selected, the air cooled by the indoor side heat exchangers 6 and 7 acting as an evaporator is supplied to the conditioned room by the blower 12 and the conditioned room is cooled. This cooling operation is performed by controlling the operation capability and the air flow rate of the compressor 1 based on the room temperature and the set value.
[0063]
When the heating cycle is selected, the air heated by the indoor side heat exchangers 6 and 7 acting as condensers is supplied to the conditioned room by the blower 12 and the conditioned room is heated. This heating operation is performed by controlling the operation capability and the air flow rate of the compressor 1 based on the room temperature and the set value.
[0064]
When the dehumidification cycle is selected, the air cooled by the evaporator and the air heated by the condenser are mixed to adjust the temperature, and then supplied to the conditioned room as dehumidified air. is there. Depending on the target humidity setting, it is divided into “dehumidifying operation” (this dehumidifying operation is selected during automatic operation), “dehumidifier”, and “laundry”.
[0065]
The target humidity is set to 55% in the “dehumidifying operation”, the target humidity is set to 50% in the “dehumidifier”, and the target humidity is set to 45% in the “laundry”. The set value of the target humidity is not limited to this value, and may be arbitrarily selected in consideration of the capacity of the unit, the comfort of the conditioned room, and the like.
[0066]
Further, the operating capacity of the compressor 1 is increased or decreased so that the humidity becomes the target humidity in each operation. For example, when the humidity is less than the target humidity -5%, the operating capacity of the compressor 1 is “0” (stopped), and when the target humidity is −5% <humidity <target humidity, the operating capacity of the compressor 1 is 20 Hz (compressed). When the target humidity <humidity <target humidity + 5%, the operating capacity of the compressor 1 is 30 Hz. When the target humidity + 5% <humidity <target humidity + 15, the compressor 1 Is 40 Hz, and when target humidity + 15 <humidity, the operating capacity of the compressor 1 is 45 Hz.
[0067]
The driving capability is not limited to these, and is arbitrarily set optimally. The same relationship is set for “dehumidifier” and “laundry”.
[0068]
In these operations, the opening degree of the electric expansion valve 4b is automatically controlled so that the temperature of the evaporator becomes constant. Furthermore, the temperature of the evaporator is corrected based on the deviation between the room temperature of the conditioned room and the set temperature, and when the deviation is large (when the room temperature is greater than the set temperature), the deviation is low (cool dehumidifying operation). When the value is negative (when the room temperature is smaller than the set temperature), it is set to be high (warm dehumidifying operation). The temperature of the evaporator is optimally set according to the capacity of the indoor heat exchanger.
[0069]
The flowchart of FIG. 4 shows the operation when “dehumidification operation”, “dehumidifier”, and “laundry” are selected, and returns to the main program via “R”. Note that the selection of “dehumidifier” and “laundry” may be provided with a separate selection switch so that it can be manually selected even when “automatic operation” is selected.
[0070]
It is determined whether “dehumidifying operation”, “dehumidifier”, or “laundry” is selected in step S1 to step S3. If “dehumidifying operation” is selected in step S1, the process proceeds to step S4. Operation is performed with the setting of “Dehumidifying operation”.
[0071]
When “dehumidifier” is selected in step S2, the process proceeds to step S5, and the operation is performed with the setting of the “dehumidifier”.
[0072]
When “laundry” is selected in step S3, the process proceeds to step S6 to determine whether or not the currently selected refrigeration cycle is a heating cycle. Alternatively, after re-deciding the state of the refrigeration cycle to be selected based on the relationship shown in FIG.
[0073]
When the heating cycle is not determined in step S6, the process proceeds to step S7, and the dehumidifying operation is performed with the “laundry” setting.
[0074]
When the condition of step S6 is satisfied, the process proceeds to step S8, where the heating operation by the heating cycle and the dehumidifying operation by the setting of the “laundry” are periodically and alternately repeated.
[0075]
In this repetition, first, the heating operation by the heating cycle is performed for 1 hour, then the dehumidifying operation by setting of “laundry” is performed for 30 minutes, and thereafter the heating operation and the dehumidifying operation are repeated. At this time, the setting value of the heating operation is set to 26 degrees at which a sufficient heating effect is obtained, but is not limited to this value, and may be arbitrarily set. Further, the heating operation maintenance time and the laundry maintenance time are also set. It may be arbitrarily set within a range where the room temperature of the conditioned room does not decrease.
[0076]
In the air conditioner configured as described above, when the environmental conditions such as the room temperature of the conditioned room are low, and / or when the outside air temperature is low, that is, when heating operation is required, When the dehumidifying operation requiring low humidity such as “is selected, the heating operation and the dehumidifying operation are alternately performed periodically, and the temperature reduction of the conditioned room can be suppressed while keeping the dehumidifying capacity high. .
[0077]
Incidentally, when the room temperature and the outside air temperature are high, the operation of “laundry” for keeping the dehumidifying capacity high is normally performed.
[0078]
【The invention's effect】
The present invention provides a heating operation for supplying air heated by a condenser in a refrigeration cycle to a conditioned room, and a dehumidifying operation for supplying the air cooled by an evaporator to the conditioned room after reheating. In the conditioner, the heating operation and the dehumidifying operation are repeated periodically.By configuring in this way, the heating operation and the dehumidifying operation are repeated. Even when the room temperature decreases, an excessive temperature decrease of the conditioned room can be suppressed by performing the heating operation.
[Brief description of the drawings]
FIG. 1 is a refrigerant circuit diagram showing a refrigeration cycle of an air conditioner showing an embodiment of the present invention.
FIG. 2 is a schematic block diagram of a control circuit used for controlling an indoor unit.
FIG. 3 is a schematic block diagram of a control circuit used for controlling an outdoor unit.
FIG. 4 is a flowchart showing the operation of the present invention.
FIG. 5 is a table for determining selection of a refrigeration cycle.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Compressor 4a Electric expansion valve 4b Electric expansion valve 6 Heat exchanger 7 Heat exchanger 33 Microcomputer 43 Room temperature sensor 45 Humidity sensor 60 Outside air temperature sensor

Claims (3)

  A compressor, a heat source side heat exchanger, a decompression device, and a refrigeration cycle in which a use side heat exchanger is connected in an annular shape using refrigerant piping, and at least the use side heat exchanger acts as a condenser. A heating cycle for supplying heated air to the conditioned room, a cooling cycle for operating the use side heat exchanger as an evaporator and supplying air cooled by the evaporator to the conditioned room, and the use side heat exchange Control of an air conditioner in which the dehumidification cycle to be supplied to the chamber to be conditioned after the air cooled by the evaporator is reheated by dividing the condenser into a part acting as a condenser and a part acting as an evaporator In the apparatus, an automatic operation control unit that automatically selects at least one of the heating cycle, the cooling cycle, and the dehumidification cycle based on an environmental condition of the conditioned room at the start of operation A heating operation by the heating cycle, a cooling operation by the cooling cycle, a first dehumidifying operation by the dehumidifying cycle, and a second dehumidifying operation in which the target humidity is set lower than the first dehumidifying operation by the dehumidifying cycle; When the second dehumidifying operation is selected and the cycle selected by the automatic operation control unit is the heating cycle, the heating operation is started for a predetermined time, and then the dehumidifying cycle and the heating cycle are selected. A control device for an air conditioner, characterized in that a control unit for periodically switching between the two is provided. The operation control unit, according to claim 1 cycle selected in the automatic driving control section when the second dehumidifying operation is selected and performing the dehumidifying operation by the dehumidification cycle when the cooling cycle or dehumidifying cycle The control apparatus of the air conditioner described in 1. The air according to claim 1 or 2 , wherein the automatic operation control further automatically selects at least one of the heating cycle, the cooling cycle, and the dehumidification cycle based on an outside air temperature. Harmonic machine control device.

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