JPS59100331A - Control on operation of air conditioner - Google Patents

Abstract

PURPOSE:To permit the removal of moisture in a necessary amount even during a low- capacity operation by using a system in which when a time-average refrigerating capacity is lowered to less than a reference value, a given high-capacity operation is made for a certain period of time, then a low-capacity operation is performed until the difference between the room temperature and a set value is eliminated, and an operation of a capacity corresponding to the following cooling load is restored. CONSTITUTION:By a comparator 11, when the reference value VA for voltage VX corresponding to a time-average frequency at which an air conditioner is operated is under the condition of VX<VA, Vfmax is selected in the selection circuit 26 by the first timer circuit 32 and held for gamma-time in a holding circuit 27. An inverter 11 is operated at fmax (operable maximum frequency) for gamma-time to secure the amount of moisture to be removed. Because of a high-frequency operation, refrigerating capacity becomes too much and the room temperature becomes less than a vet value. By the selection circuit 26, Vfmin is selected and held by the holding circuit 27 until the deviation between the room temperature and set value is zeroed. The inverter 11 is operated at fmin (operable lowest frequency), and the refrigerating capacity is saved until the room temperature and the set value are balanced. The difference is eliminated and the usual operation is restored.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the operation of an air conditioner, and particularly to a method for controlling the operation of an air conditioner with a dehumidifying function such as various air conditioners and refrigerators.

As one of the conventional air conditioners aimed at energy saving, the power frequency of the motor for the refrigerant compressor is made variable to adjust the amount of refrigerant circulation and control the heating and cooling capacity to match the load. There is a converter with stepless capacity town converter nitrogen air conditioner.

This principle will be explained based on FIG. (Thick lines are refrigerant pipes, thin lines are electrical signals.

In the case of heating operation, the refrigerant compressed in compressor l is →
As shown in , it passes through the cooling and heating switch
(operates as a condenser), passes through the check valve 5, expands adiabatically at expansion 6, evaporates in the outdoor heat exchanger 8 (operates as an evaporator), and then passes through the four-way cooling/heating switching valve 2 again. The liquid is configured to be returned to the compressor 1 via the liquid receiver 9.

When the refrigerant is condensed in the indoor heat exchanger 3, a heating effect is obtained.

In the case of cooling operation, the refrigerant compressed in the compressor is
As shown in..., it passes through the cooling/heating switching four-way force 2, is condensed in the outdoor heat exchanger 8 (operates as a condenser), approaches the check valve 7, expands adiabatically with expansion -jf4, and enters the indoor heat exchanger. 3 (operates as an evaporator), passes through the cooling/heating switching four-way valve 2 again, and returns to the compressor 1 via the liquid receiver 9.

When the refrigerant evaporates in the guided heat exchanger 3, a cooling effect is obtained.

In this device, the room temperature is detected by a temperature-sensitive resistance element 12, and the difference between the room temperature and the room temperature set in advance in the temperature setting device 13 is detected by means of a potential difference. generating a signal with a frequency controller 10;
The signal is output to the inverter 11, which converts the commercial frequency in response to the signal from the frequency control device 10, and changes the rotational speed of the drive motor of the compressor 1.

As shown in FIG. 3, the frequency control device 10 includes a potential difference detection circuit 14 and a control circuit J5.

The frequency control unit WIO detects the potential difference between the temperature-sensitive resistance element 12, which detects the temperature in the room that is air-conditioned by this air conditioner, and the temperature setting device 13 using the potential difference detection 14, and uses this detected signal. In response to this, the control circuit 15 generates a control signal (refrigeration capacity control signal) that reduces the deviation between the indoor temperature and the set temperature, and outputs it to the inverter 1.

The inverter 11 converts the commercial frequency in response to a signal from the frequency control device g3o, operates the induction motor at the converted frequency, and drives the compressor l.

In this way, the induction motor of the compressor 1 is driven by the frequency controller IQ and the inverter (frequency converter) 1 at a frequency fL that matches the air conditioning load.

Therefore, the compressor l rotates at a rotational speed corresponding to the □frequency fr, and the air conditioner generates a heating and cooling capacity approximately proportional to this rotational speed.

When the air conditioning load decreases, saving capacity by operating at a low frequency will improve energy consumption efficiency because a large heat exchanger will be required for the amount of refrigerant circulation.

In addition, since the frequency fL is controlled moment by moment to match the air conditioning load, constant temperature control (control to keep the room temperature at a constant value) is possible, and cooling capacity control by 0N10FF control of the compressor in air conditioners without an inverter is possible. In comparison, it is possible to operate with high average energy consumption efficiency over a period of time.

In other words, the frequency conversion type continuously variable capacity air conditioner can save energy both in terms of energy consumption efficiency and period average energy consumption efficiency.

However, as a drawback of the conventional frequency control device, the following situation occurs during cooling operation.

That is, when the air conditioning load is low, the operating cycle V number is naturally low (refrigeration capacity is low).

The relationship between dehumidification capacity (amount of dehumidification per unit time) and refrigeration capacity (proportional to operating frequency) is shown in Figure 2. At low frequencies, the dehumidification capacity decreases significantly, and at frequencies below fy, the dehumidification capacity decreases. It becomes impossible to do so.

Therefore, when the negative air conditioner hj remains small for a certain period of time, the indoor temperature reaches the desired temperature, but since no dehumidification is performed, the cooling operation is performed with high relative humidity, resulting in a poor sensation.

In this way, when the air conditioning load during cooling is small, the conventional capacity change nitrogen air conditioner operates at a low capacity, but in this case, the temperature can be maintained at the set value, but the amount of dehumidification cannot be ensured. □ The present invention was developed in view of these drawbacks, and its purpose is to reduce humidity during cooling. When the air conditioning load is small:
In other words, it is a method of controlling the operation of an air conditioner that allows the necessary amount of dehumidification even when operating at low capacity.

That is, in the present invention, in an air conditioner that can adjust the refrigeration capacity, when the time-average refrigeration capacity becomes below the reference value,
It is characterized by operating at a predetermined high capacity for a certain period of time, then operating at a predetermined low capacity until there is no deviation between the room temperature and the set value, and then returning to operation at a capacity corresponding to the cold-blooded load. This is a method for controlling the operation of an air conditioner.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

FIG. 4 is a block diagram showing the configuration of an embodiment of an apparatus that is used to carry out the method of the present invention.

In FIG. 4, the frequency control device 10a includes a temperature sensitive resistance element 20, a temperature setting device 2, a potential difference detection circuit 22, a control circuit 23, reference voltage generation circuits 24, 25, 30, . Selection circuit 2
6, holding circuit 27, integrator 28, multiplier 29, comparator 3
It is composed of a first timer circuit 32, a second timer circuit 33, and a heating/cooling switching circuit 34.

Moreover, the connections of these components are as follows. The potential difference detection circuit 22 receives signals from the temperature sensitive resistance element 20 and the temperature setting device 2, and outputs the detected potential difference to the control circuit 23.

The selection circuit 26 includes a control circuit 23, a reference voltage generation circuit 24.
25 and sends an output signal to the holding circuit 27.

The holding circuit 27 is connected to the inverter 11. Further, the cooling/heating switching circuit 34 is connected to the control circuit 23 and the integrator 28, and the output of the integrator 28 is inputted to the comparator 31 via the multiplier 1 and the integrator 29. The reference voltage generating circuit 3Q is also input to the comparator 31.

The comparator 3 outputs a digital signal to the selection circuit 26 and the first timer circuit 32, and the first timer circuit 32
The selection circuit 26, the holding circuit 27, and the second timer circuit 33 output a heterogeneous signal.

Further, the second timer circuit 33 includes the potential difference detection circuit 2.
Two signals are input, and digital signals are output to the holding circuit 27 and the integrator 28. The solid lines in FIG. 4 indicate analog signals, and the broken lines indicate digital signals.

The operation of the frequency control device 10a is as described below.

The potential difference detection circuit 22 detects the potential difference between the temperature sensitive resistance element 20 and the temperature setting device 21, which are installed at an appropriate location in the room to be nitrogen-conditioned, and the control circuit 23 adjusts the voltage according to the magnitude of the potential difference. Outputs Vf. Reference voltage generation circuit 24
．． 25 generate voltages of Vfg (the inverter generates the highest operable frequency) and Vfm (the inverter generates the lowest operable frequency), respectively, and the selection circuit 26 generates the digital signal 50 of the comparator 3 or the voltage Vfm (the inverter generates the lowest operable frequency). 1 timer circuit 3
Vf, Vf m,
Select one of Vf-.

That is, when both signals 50 and 52 are at low level, Vf is selected, when signal 50 is at high level, Vfsw is selected,
Vfm is selected when signal 52 is high 17 bells.

When both signals 50 and 52 are at a low level, Vf is selected and Vf is directly outputted to the inverter 1 via the holding circuit 27, and the inverter 11 is operated at a frequency corresponding to the voltage Vf.

If the signal 50 becomes high level and the Vf attack is selected, the first
Digital signal 5 of the timer circuit 32 becomes high level 1
During this time, Vfg is held in the holding circuit 27 and output.

When the signal 52 becomes high level and Vfsln is selected, the holding circuit 27 holds the Vf illusion while the digital signal 53 of the second timer circuit 33 is high level.
Output.

The output signal of the control circuit w523 is cold v! during cooling operation. The air is sent to the integrator 28 via the 1st switching circuit 34; however, during heating operation, the cooling/heating switching circuit 34 is turned off and the air is disconnected from the integrator 28.

Therefore, during heating operation, the output voltage V from the control circuit 23
f is constantly output to the inverter 11.

Now, during continuous cooling, the signal sent to the integrator 28 is integrated, and the value multiplied by the multiplier 29 is compared with the voltage generated by the reference voltage generation circuit 30 in the comparator 3, and the former value is is smaller than the latter value, the signal comparator 31 makes the digital signal 5/5o high level.

Otherwise, the digital signal 5o is at a low level.

The first timer circuit 32 sets the signal 51 to a high level for one hour when the digital No. 46 5o becomes high level, and issues a high level to the signal 52 after 7 hours. When the signal 53 is emitted, the signal 53 becomes high level.

The signal 53 at a high level is transmitted to the potential difference detection circuit 22.
When the analog signal 55, which is the output of , becomes OV, it becomes a low level.

When the signal 53 goes from high level to low level, the signal 54
becomes high level, resets the integration of the integrator 28, and the integrator 28 starts a new integration.

For reference, the timing chart of Iro Nos. 50 to 54 is shown in Figure 5. In the Nokaro modified air hooking machine using the 0 Inva, - Yu, the cooling operation at low frequency is as shown in Figure 2. The dehumidification capacity decreases and the necessary amount of dehumidification is no longer possible, and even if the temperature reaches the set value, the relative humidity is high and becomes uncomfortable.

In order to reduce such a situation, according to the method of the present invention, the sixth
Operate as shown in the diagram.

That is, when the comparator 31 operates the air conditioner, dt: T is the time from the start of integration, and Vx is the integrator 28 and multiplier 29.
The voltage obtained through Vx (V
When condition f42 of A is satisfied, the width selection width 1 circuit 26 selects Vf by the first timer circuit 32, and the holding circuit 27 holds 1 Vf at time τ. ) is τ time sub-turn frequency is f
-C (maximum operable frequency), and during this time the amount of dehumidification is ensured.

However, with this operation, the amount of dehumidification can be ensured, but because of the high frequency operation, the refrigeration capacity and storage capacity are increased, resulting in the room temperature falling below the set value.

Therefore, after one hour of high frequency operation σ) first timer circuit 32
The higher level coefficient 52 causes the selection circuit 26 to select Vfm.
is selected, and the holding circuit 27 operates at the lowest frequency that maintains Vfm until there is no deviation between the room temperature and the set value, and the refrigeration capacity is saved until the room temperature and the set value are balanced.

After these deviations disappear, normal operation returns. At the same time, the second timer circuit 33 resets the integrator 28, and the integrator 28 starts a new integration. As explained above, according to the present invention, For example, the amount of dehumidification can be ensured during low capacity operation with a small air conditioning load, and the room temperature can be maintained at the set value.

In addition, another embodiment of the "Next Kieri" method that improves comfort during low-capacity operation with a small empty Wd load will be described.

In the above embodiment, the frequency for ensuring a dehumidified grave is set to the maximum operable frequency f-, but this does not necessarily have to be f=, and any frequency close to f- is sufficient.

Similarly, the frequency after f- is set to f-1=(minimum operable frequency), but this may also be a frequency close to fM.

Further, the variable capacity mechanism of the above embodiment uses a frequency conversion device (inverter), but in the variable capacity mechanism using a binary combiner sub-block (see Japanese Patent Application No. 104979/1989), instead of the frequency, By controlling the number of units, the functions of the present invention can be implemented in the same way, and it can also be applied to other systems in which the refrigerating capacity can be changed steplessly or in multiple stages. Furthermore, it may also be applied to a dedicated refrigeration machine. Further, the refrigeration capacity 1-inch mechanism may be of any type.

[Brief explanation of the drawing]

Figures 1 to 3 show conventional examples. Figure 1 shows the frequency conversion stepless capacity variable air conditioning system (without showing the principle of stability), and Figure 2 shows the dehumidification capacity and operating frequency. A diagram showing the relationship between
FIG. 3 is a detailed diagram of the frequency 1fllJ control device in FIG. 1, FIG. 4 is a block diagram showing the configuration of an embodiment of the device used to carry out the method of the present invention, and FIG. FIG. 6 is a diagram showing a timing chart of each signal, and FIG. 6 is a diagram showing an operating state according to the present invention. 1... Pressure machine, 2... Cooling/heating switching west valve, 3... Indoor heat exchanger, 4... Expansion valve, 5... Check valve, 6...
Expansion valve, 7... Check valve, 8... Outdoor heat exchanger, 9.
. . . Liquid receiver, 10 . . . Frequency control device, 1 No. . Control circuit, 10a... Frequency control device, 20... Temperature sensitive resistance element, 2I... Temperature setter, 22... Potential difference detection circuit,
23... Control circuit, 24, 25. 30... Reference voltage generation circuit, 26... Selection circuit, 27... Holding circuit,
28... Integrator, 29... Multiplier, 3rd... Comparator, 32... 1st timer circuit, 33...@2 timer circuit, 34... Cooling/heating switching circuit, 50. 51.52.5
3.54...digital signal, 55...analog signal. Applicant Shun Patent Attorney Takehiko Suzue Figure 1 141-112 3 Tsuri 1111 J 115v!J Figure 6 Fukan

Claims (1)

[Claims] In an air conditioner whose refrigerating capacity can be adjusted, when the time-average refrigerating capacity falls below the standard value, it operates at a specified high capacity for a certain period of time, and then operates at a specified low capacity until there is no deviation between the room temperature and the set value. A method for controlling the operation of an air conditioner, characterized in that the air conditioner is returned to operation at a capacity corresponding to the cooling load.