JPS61191823A - Air conditioner - Google Patents

Abstract

PURPOSE:To increase the reliability of a heat pump without impairing comfortableness of the room by carrying out an appropriate damper control at the time of a low load and to smoothen the operation of the heat pump in a system utilizing the heat pump for a heat source apparatus. CONSTITUTION:Thermal load measuring means 19 calculates a thermal load based on a difference between the room temperature set by a room thermostat 14 and the room temperature at the present time. By the thermal load thus calculated, the damper opening degree of a branch duct 7 is discriminated by damper control quantity discriminating means 20. Further, by the discriminated total opening degree of a damper 9, the change of the set room temperature is carried out by set room temperature determining means 21. Based on this result, the damper 9 is controlled by damper control means 22, and then the pressure and the temperature within the duct 6 after the damper control are detected. Based on this detection signal, the operational condition is measured by operational condition measuring means 23 and the rotational speed of the blower 5 is determined based on the pressure signal by blower rotational speed determining means 24 to control the blower 5. Based on the temperature signal the ability of a compressor 18 (heat pump) is determined by ability determining means 26 to control the ability of the compressor 18 to make the ON and OFF operations of the compressor 18 to the minimum.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an air conditioner that employs a variable air volume control system that can independently adjust the room temperature of each room.

[Conventional technology]

Central air conditioning systems, which use air ducts to distribute temperature-controlled air to each room for air conditioning, can easily incorporate humidifiers and high-performance filters, and can also employ outside air processing and total heat exchangers. Quality air conditioning can do &sl
It has many advantages over heat pump chiller/fan coil systems and packaged air conditioner distribution systems, such as the fact that the room being air-conditioned only has an air outlet and an air inlet, making efficient use of indoor space, and fewer problems with the heat transfer system. ing. Therefore, it is used for building air conditioning. Among them, variable air volume control method (hereinafter referred to as M) enables energy-saving operation.
The AY method (called the AY method) can independently control the temperature of each room with a different heat load.1 It is also possible to stop air conditioning in rooms that are not in use, and reduce operating costs by varying the power of the blower depending on the amount of air required. It is also possible to reduce the capacity of the heat source device by considering the simultaneous usage rate.

There are two types of vAv systems depending on the type of damper for adjusting air volume. One is a system using a bypass type vAv unit (damper unit), which adjusts the ratio of the amount of air blown into the room and the amount of air directly returned (bypassed) to the heat source device according to the indoor load. Since the amount of air blown is constant in this system, it is difficult to control the capacity of the heat source equipment.Although this method is often used in systems using packaged air conditioners, there is no energy saving effect by controlling one fan.

The other method uses a diaphragm-type vAv unit, which adjusts the amount of air blown into the room to an arbitrary value depending on the indoor load. This method detects the pressure inside the duct, which changes according to the opening degree of the damper, and controls the capacity of the blower so that this value becomes a certain value. (The temperature of the air inside is controlled to be constant), the required capacity of the heat source equipment is reduced, and at the same time, the power of the blower is also reduced.

FIG. 2 is a system configuration diagram of a conventional air conditioner as well as the basis of the present invention, where l is a room to be air conditioned. Here, a case of three rooms is shown.

This is a fan coil unit placed in the ceiling, and air filter 3. Heat exchanger-tei, blower! It consists of 6 is the main duct connected to the fan coil unit - 〇 air outlet, ri is the three branch ducts branched from this main duct, t is the throttle-shaped VAV unit inserted in the middle of this branch duct, 9 is a damper rotatably installed in this MAY unit, IO is an air outlet installed at the end of the branch duct, l/ is an inlet installed at the bottom of the door of room l, l is the ceiling of the hallway The ceiling suction port 13 provided on the surface is a suction duct that connects this ceiling suction port with the suction port of the fan coil Yuetco, and Lda is the room thermostat installed in each of the above rooms.
13 is a temperature sensor S/ installed in the main duct 6.
Similarly, A is a pressure sensor with a detection section installed inside the main retrofit, and is a control device attached to the above fan coil unit. In conventional air conditioners, the opening degree of the damper 9 is adjusted to an arbitrary position according to the temperature difference between the set temperature set by the user and the detected current air temperature. ing. Therefore, the pressure inside the main duct 6 changes according to the opening degree of the damper 9, which is detected by the pressure sensor 16 and
The capacity of blower 3 was changed to prevent excessive pressure. In addition, heat exchange W! due to changes in air flow rate! Since the temperature of the outlet air of III changes, this concentration is detected by temperature sensor/3 and the temperature or circulation rate of the heat medium to the heat exchanger is changed so that the air temperature reaches a preset temperature.

The heat exchanger is generally connected to a hot and cold water storage tank. In addition, the air that has been conditioned in the room 1 flows from the suction port // through spaces such as hallways to the ceiling suction port 1, and then flows through the suction duct /, 7
Return to Funcoil Yuetko via .
゛The control method for the blower 3 is: -Static pressure control method.
A variable static pressure control method using an airflow sensor is well known.

In addition, in Figure 2, the return air is returned using a corridor, etc., but there are 7 uncoiled units from each room.
There is also a method that increases controllability and further energy savings by installing a return duct all the way to the top.

Further, in FIG. 2, the branch ducts are separated from the main duct 6, but there is also a method in which the main duct is not provided and the branch ducts are arranged in an octopus-like shape from the fan coil unit.

In addition to the type shown in FIG. 2, there are other types of fan coil units, such as a ceiling-suspended type and a floor-standing type.

[Problem that the invention seeks to solve]

Conventional air conditioners are configured as above, so
A system using a bypass type vAY unit has poor energy saving properties. In addition, in a system using a diaphragm type vAv unit, if a direct expansion type heat pump is used as a heat source in a small system such as a house or store, the number of rooms used at the same time is small, and forced ventilation is not required. Since this is often not done, the heat load is small, and each damper may be fully closed at the same time, making it difficult to control the heat source (heat pump). Another problem is that reliability cannot be improved. ゛This invention solves the above-mentioned problems, and in a system using a heat pump as a heat source, it is possible to perform appropriate damper control at low loads, The purpose of the present invention is to provide an air conditioner in which the reliability of the heat pump is improved without impairing the comfort of the room due to the bumps that facilitate smooth operation.

[Means for solving the problem] The air conditioner according to this invention is a heat pump.
.

a room thermostat for each room that detects the temperature of each room to which cold and hot air is distributed via the duct; a heat load measuring means that measures the heat load based on the output signal of the room thermostat; damper control amount determining means for determining the damper opening degree of the branch duct from the measurement results; and changing the setting value of the room thermostat based on the total control amount of each damper determined by the damper control amount determining means. a damper control means for controlling the damper opening degree based on the output signal of which determining means; and a damper control means for controlling the damper by detecting the pressure and temperature inside the duct after damper control glJ, and operating according to the detection signal. means for measuring the operating state; means for determining the rotational speed of the blower based on the pressure signal from the operating state measuring means; and means for determining the compressor capacity based on the temperature signal; It consists of a means for controlling.

[Effect]

In this invention, the heat load measuring means calculates the heat load based on the difference between the room temperature set by the room thermostat and the current room temperature, and determines the damper control amount based on the damper opening degree of the branch duct. Judging by means - Sara K
The set room temperature is changed by the set room temperature determining means based on the total damper function determined by W. Based on this result, the state of the damper control means is measured by the operating state measuring means, and the rotation speed of the blower is determined by the pressure signal. The determination means determines the capacity of the compressor and controls the blower, and the capacity determination means determines the capacity of the compressor based on the precise temperature signal.By controlling in this way, the compressor is turned on and off. Minimize off.

〔Example〕

FIG. 1 is a diagram showing the basic configuration of an air conditioner according to the present invention. In this invention, as is clear from FIG.
A heat pump 1 as a heat source device, a blower that sends cold and hot air from the heat pump IT to each room 1 through the main duct 6 and branch ducts, and a damper pub with an air volume of 1 ItrJ placed in the branch duct 1. A room thermostat installed in each room and a temperature sensor 13 and a pressure sensor 16 installed in the duct 6 are provided, and the output signal of each room thermostat is inputted to a heat load measuring means. 1 This heat load measuring means/9 measures the magnitude of heat load. -〇 is the damper 90 based on the output of the heat load measuring means/de.
It is a damper control amount determining means for determining the control amount and is 1 piece 1 I
Ii is a set room temperature determining means that determines whether or not to change the set room temperature based on the determination result; 02λ is a damper control means that controls the opening degree of the damper pub based on the determination result of the set room temperature determining means -/; This is an operating state measuring device that detects the temperature and pressure inside the duct 6 after damper control with a temperature sensor 1 and a pressure sensor 6, and measures the operating state of the device based on the detection signal. This is a blower rotation speed determining means that determines the optimum rotation speed of the blower 3 based on the pressure output signal measured by the device 3. The rotation speed determining means includes: Controls the blower 3 based on the determined output. A control means 2S is connected thereto.

The roller is a capacity determining means that determines the optimum capacity of the heat pump (compression tlA) 1g based on the temperature output signal measured by the operating state measuring means 3, and the capacity determining means 6 is a A capacity control means for controlling the capacity of the heat pump/g is connected.

Figure 3 shows the overall configuration of the heat pump/g. 1. A variable displacement (variable rotational speed) compressor, a VB valve code, a heat exchanger on the indoor side, and a plunger operated by an electromagnet. Expansion valve 30 that can be moved to any position to adjust the flow rate of refrigerant. Outdoor heat exchanger J/ and accumulator 3
These are connected in a ring to form a refrigeration circuit.

In addition, the outdoor blower attached to the outdoor heat exchanger 31 is manufactured by 3 companies.

Figures 4(a) and 4(b) show the details of WAY unit) ff, which shows the damper motor 3 which uses a stepping motor that rotates the damper 9 in forward and reverse directions at any angle, and the damper motor 3. A limit switch 33 for detecting the position of N limit switch t? j is attached to the damper 9 in the fully closed position.

FIG. 5 is a circuit diagram showing a concrete sequence of the present invention corresponding to the principle configuration of FIG.
A memory 311 for storing calculation results etc. in PU and 7.
Timer 39. It consists of an input circuit DAO and an output circuit DA1. The octopus is each room thermostat/l and temperature sensor/3. The detection output of the pressure sensor 16 is input to an analog multiplexer, and the converter 3 is a converter that converts the output into a digital signal.The digital output signal is given to the input circuit. Da-tei is an operation switch, and its status signal is applied to the input circuit DaO together with the limit switch Jj. 446a~da! f is a photocoupler 88R connected to the output circuit D1 for each control device, and an inverter 6 is connected between this photocoupler 5S144TA and the compressor S.

Also photocoupler 5SR4! A thyristor controller dac is installed between jb and the blower 30, and an expansion valve controller Ql is installed between the photocoupler/SSR da 3c and the expansion valve JO.
A damper controller dub is connected between the photocoupler SSR $j"d and the damper motor 31I, an outdoor blower 33 is connected to the photocoupler SSR da 3e, and a western valveco 9 is connected to the photocoupler SSR da jf. !to is an AC and DC power source that drives each device.

Next, the operation of the above embodiment will be explained with reference to FIGS. 6 to 9. Fig. 6 is a main flowchart showing the control program stored in the memory 3gVC of the microcomputer 36, Fig. 7 is a subroutine flowchart for damper control, Fig. 8 is a subroutine flowchart for blower control, and Fig. 9 is a subroutine flowchart for compressor control. 〇The operation from now on will be explained using heating operation.

First, step! When the operation switch is set to heating or cooling operation (heating in this case) at 1, the ON signal is input to the input circuit IIO and operation starts. By operating this operation switch Dada, control constants necessary for heating or cooling operation are set from the memory Jg while the CPU is reading (steps j-J, j-J). Next, initial settings for each damper 9 are performed in the static system 31I. The damper motor 3da rotates once until the limit switch 33 operates (until it becomes fully closed), and then is set to the fully open position. At this time, the exact position of damper 9 is stored in memory 3tK.
be remembered. Then enters the normal control loop and timer 3
9, the control loop is repeated at regular time intervals (step 33). Step first! At 6, 0N10FF of the west valve 9 and the outdoor blower JJ is determined, and the photocoupler S S RIIje is output from the output circuit 1/.

The west valve knob and the outdoor blower 33 are controlled via the door 3f. Next, the process moves to step 3, damper control, and the control program shown in FIG. 7 is executed. That is, the heat load measurement operation is performed in step 3g of FIG. 7, and the room temperature To set from each room thermostat L and the current room
The signal of s is sent to an analog multiplexer and an A/D converter.3. Input circuit u.

It is taken into the CPU, 7th node via . Next step!
The damper control amount determination operation starts from t to 63. The step is to see if all the dampers 9 are already fully closed in this operation! ? When the valve is fully closed, it is bypassed and the process moves to step 63, which will be described later. If not, To and T1 are compared in step 60, and when T1 is lower than ('rot), it is determined in step 61 that the damper pub is fully open (±t is a dead zone above and below To). t7ThT, is ('r
0+t), the damper pub is determined to be fully closed (step 6). Further, when T1 is within (T0±t), it is determined that the opening degree of the damper 9 does not change. Step 60-
The processing of 6 items is carried out in all nil rooms, and its completion is determined in step 63.

If "YE8J", the next step 6-6S enters the set room temperature determination operation.
If it is determined in the previous damper control amount determination operation that all dampers 9 are not fully closed, one step 4fK is bypassed. If not, that is, if all damper pubs are fully closed, the process moves to step 63, where To and T1 are compared again, and when T is lower than (To tg), damper 9 is determined to be fully open in step 66. (t *t
1 (relationship of 1) in the lower dead zone of i'r0.

Further, when T is higher than (To-ta), it is determined in step 6 that the damper 9 is fully closed. This determination is made for all rooms l (step btr>).The above results are transmitted from the output circuit D/ to the damper controller lI9 via the photocoupler 8SR4!jd by the damper control operation of the next step 76?, and the damper motor Rotate j4C forward/
Reverse the rotation to fully open or close the damper 9. Next, the sixth
Moving on to indoor blower control in step O in the figure, the control program shown in FIG. 8 is executed. In step 1 of FIG. 8, the operation state a measurement operation is performed, and the temperature sensor 13
The signals (T, and P) of the pressure cassette 16 are sent to an analog multiplexer and an A/D converter 3. Input circuit 4! The data is taken into the CPU and 7 via the Next step Kuko~
Then, the blower rotation speed determination operation consisting of step t begins. In step-cooling, it is determined whether all dampers t are fully closed, and if they are fully closed, it is the blower! Bypass 0FFI (step 3) to step 3. If it is not fully closed, proceed to step Kuda and determine the ON10FF state of blower 5. If 1 is also in LOFF state, go to step 3 and blower! Turn on and proceed to the next step. In the step chronograph, the set pressure P0 in the main duct 6 stored in the memory 3 is compared with the pressure P detected in the previous step chronograph, and if Po>P, the pressure is The rotation speed of blower j is increased (step Kuko).

If the relationship is 7ThPo<P, the rotation speed of the blower 3 is similarly decreased (step ff), and if P is within the dead zone of Po, the rotation speed is not changed and the process moves to the next blower control operation (step 9). . The control output from the CPU 37 is given from the output circuit lI/ to the thyristor controller dak via the photocoupler 5SB94-b, where the AC waveform is controlled by the thyristor and output to the blower 3 to arbitrarily adjust the rotation speed. . Thereafter, the process moves to compressor control in step SO shown in the main program of FIG. FIG. 9 shows the processing program, in which the capacity determination operation is performed by skipping steps g/N. First, in step 1/, it is determined whether all dampers 9 are fully closed, and if they are fully closed, the compressor-S is bypassed to 0FFL in step 1 and to step lt. If 1 is not fully closed, the QN10FF state of the compressor t is determined in step t3, and if 1 is also in the LOFF state, the compressor 8 is turned on in step &'1 and the process proceeds to the next step tr. Step Ir! Now, store the set air temperature T in the main duct 6 stored in the memory 3, and the temperature T detected in the previous step 1! are compared, T,
〉T, then the compressor -t depends on the difference between T and T.
The rotational speed is increased (step 16), and if Ts<Tt, the rotational speed is decreased (step g).

Further, if T is within the dead zone of T, the rotation speed is not changed and the process moves to the next capacity control operation (step tg). CE"U
The control output from , 7 is connected to the photocoupler from the output circuit.
It is applied to the impertada 6 via the 5SR1ja, where the frequency and voltage of the AC power source are controlled, and the compressor fK is output to arbitrarily adjust the rotation speed. The capacity of the heat pump/l changes depending on the rotational speed of the compressor S, and the temperature of the outlet air of the heat exchanger on the indoor side of the LS is adjusted. Next, the expansion valve 30 is controlled according to the rotational speed of the compressor-t and the outside air temperature (step!?), and further defrost control (step? O) is performed, and the process returns to step 1 and step 3. is repeated. The details of the 19°90 step and the safety circuit of the system are omitted as they are not closely related to the content of the invention.

The results of the above control are shown in Section 10. This will be explained with reference to the diagram and the operation result explanatory diagram of FIG. For example, when multiple rooms l are to be emptied (heated) at the same time, the room temperature is lower than the set value after the operation starts, so the damper 9 is operated in a fully open state, and the rotational speed of the blower and compressor -g is also controlled to be high. be done. When the room temperature rises and reaches the set value, the damper pub repeats fully open and fully closed operations to maintain the air per room within the range of the set value T0. At this time, the air blower is controlled according to the total opening degree of the plurality of dampers 9.
The amount of air blown is also kept approximately constant. If by chance all the openings of multiple damper pubs are closed, blower 3 and compressor-t
is temporarily turned off. In this state, the next time any damper 9 is opened is when the room temperature is 'r, -t,
Until this point, the blower and compressor remain OFF. t.

If the value of is increased, the stop time of compressor-g will be extended, but
As the room temperature fluctuates greatly, compressor-t is turned ON1.
t considering the reliability associated with 0 F F.

Determine the value of Note that when only the - room is air-conditioned, the room temperature always fluctuates between To-t, T, and +t.

In the above embodiment, the room temperature is controlled by controlling the opening degree of the damper pub to be fully open or fully closed.
When damper 9 is open, hot air is supplied to room L at the maximum air volume (wind speed), and when damper 9 is closed, the air volume is zero, so the vertical temperature distribution of room L is particularly small during heating, creating a comfortable living space. be able to.

In addition to the above method, it is possible to apply the aperture method used in conventional VAV units to the present invention. In this case, set the total minimum opening of damper 9 L (For example, if there are 3 VAV units, set the total opening to 50 strokes as the minimum value) When this opening is below - Blower 3 and compressor - Apply g to the stop LS and t to the dead zone.

In addition, in the above embodiment, when all the dampers t are closed, the width of the dead zone of the set room temperature in all rooms/is varied, but the width of the dead zone is kept constant, and the set room temperature itself is set low during heating.
A similar effect can be obtained even if the temperature is set to a high value during cooling.

Furthermore, in the above embodiment, the rotation speed control using a thyristor is not performed in the blower control means-3, and the capacity control means]
An inverter may be used as well.

In addition, in the above embodiment, one compressor-g was used and its capacity was varied by an inverter, but in order to expand the capacity control range, multiple compressors were used and an inverter was also used to control the capacity. If this is done, the capacity can be controlled even more commensurate with the heat load, and the number of ON10FF operations of the compressor-8 can be reduced.In the above embodiment, a heat pump is used as the heat source, but the fan coil unit IC , 911. For example, it is possible to apply this control method to an air conditioner incorporating an auxiliary heater such as a gas furnace. Mana1 In the above embodiment, the pressure inside the duct and the air temperature are simultaneously detected, the operating state of the device is measured by the operating state measuring means, and then the blower-compressor is controlled. The air temperature may be detected and the blower controlled, and then the air temperature may be detected and the compressor controlled.

〔Effect of the invention〕

As described above, according to the present invention, when the heat load is reduced and all the dampers in each room are closed and the compressor is stopped, the time until the next damper is opened can be changed by changing the set room temperature. Since it is configured to stretch, the compressor's low temperature
This eliminates N10FF, which has the effect of improving the reliability of the compressor.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the principle configuration of an air conditioner according to the present invention, Fig. 2
The figure is an overall configuration diagram of a system using an air conditioner according to an embodiment of this invention and a conventional example, FIG. 3 is a configuration diagram of a heat pump according to an embodiment of this invention, and FIG.
4(b) is a front view showing details of the V unit, FIG. 5 is a side view thereof, FIG. 10 and 11 are explanatory diagrams for explaining the operation results of this invention. In the figure, 3 is a blower, t is a damper, and S/4c is a room. Thermostat S13 is a temperature sensor, /A is a pressure sensor, /S
is a heat pump, 19 is a heat load measuring means, -〇 is a damper control amount determining means, -l is a set room temperature determining means S is a damper controlling means, 3 is an operating state measuring means 1 is a blower rotation speed determining means, 3 is a blower control means, Koro is a capacity determining means, and 1 Koku is a capacity control means. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (13)

[Claims] (1) A heat pump used in a refrigerant compression type air conditioner, a duct and blower consisting of a main duct and branch ducts that distribute air heated or cooled by the heat pump to multiple rooms, and a blower for each room in the branch duct. A damper for adjusting the air volume placed in each room, a heat load measuring means for measuring the heat load by inputting the detection signal of the room thermostat installed in each room, and an opening degree of the damper based on the output of this heat load measuring means. a damper control amount determination means for determining a damper control amount determination means, a set room temperature determination means for determining a change in a setting value of the room thermostat based on the total control amount of each damper determined by the damper control amount determination means, and a set room temperature determination means for determining a set value of the room thermostat. a damper control means that controls the opening degree of the damper based on the output of the damper, a pressure detector that detects the pressure in the duct after damper control, and a temperature sensor that also detects the air temperature in the duct. an operating state measuring means for measuring the operating state of the operating state; a blower rotational speed determining means for determining the rotational speed of the blower based on the output of the operating state measuring means; and controlling the rotational speed of the blower based on the output of the blower rotational speed determining means. an air conditioner comprising: a blower control means for controlling the heat pump; a capacity determining means for determining the capacity of the heat pump based on the output of the operating state measuring means; and a capacity control means for controlling the capacity of the heat pump based on the output of the capacity determining means. (2) The heat load measuring means is adapted to calculate the heat load by measuring the temperature difference between the set room temperature set by the user in advance and the current room temperature. harmonizer. (3) The opening degree of the damper is determined or controlled to be either 0% or 100% by the damper control amount determining means and the damper control means. The air conditioner described in 2). (4) Claims (1) or (2) above, wherein the opening degree of the damper is determined or controlled to be an arbitrary opening degree by a damper control amount determination means and a damper control means. Air conditioner as described. (5) When the total opening degree of each damper determined by the damper control amount determining means becomes 0% or less than the minimum set value, the set room temperature determining means determines the width of the upper and lower dead zones of the set room temperature during heating. Claims (1) to (4) in which the low temperature side is temporarily increased and the high temperature side is temporarily increased during cooling.
The air conditioner described in any of the paragraphs. (6) When the total opening degree of each damper determined by the damper control amount determining means becomes 0% or less than the minimum set value, the set room temperature determining means temporarily sets the set room temperature to a lower value during heating. Claim No. 3 (2015) in which the temperature is increased during cooling.
The air conditioner according to any one of items 1) to (4). (7) The blower rotation speed determining means determines the rotation speed so that the pressure within the duct is approximately constant at a predetermined pressure.
The air conditioner according to any of item 6). (8) The air conditioner according to any one of claims (1) to (7), wherein an inverter is used as the blower control means. (9) An air conditioner according to any one of claims (1) to (7), in which a thyristor is used as the blower control means. (10) The capacity determining means is configured to determine the capacity of the heat pump so that the air temperature within the duct is substantially constant at a predetermined temperature. The air conditioner described in any of the above. (11) Claims (1) to (1) in which an inverter for varying the rotation speed of the compressor is used as the capacity control means.
The air conditioner according to any of item 0). (12) Claims (1) to 1 which use a combination of compressor number control and an inverter as the capacity control means.
The air conditioner according to any of Item 1. (13) Claim (1) in which the heat load measuring means, the damper control amount determining means, the set room temperature determining means, the operating state measuring means, the blower rotation speed determining means, and the capacity determining means are realized by a microcomputer. The air conditioner according to any one of items 1 to 12.