JPH09243144A - Method for controlling inverter type air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for controlling an inverter type air conditioner which can continuously operate a compressor by reducing the number of stopping times of the compressor as much as possible even when any controlling method of PID control, fuzzy control and zone control is used. SOLUTION: The operating frequency M of a compressor 12 is lowered at a normal change speed ΔM until the indoor temperature Th approaches a set temperature Ts to arrive at a thermometal cutoff temperature Toff. When the temperature Th approaches the temperature Ts and arrives at the temperature Toff exceeding the temperature Ts, the change speed of the frequency M of the compressor 12 is lowered from the speed ΔM to off-time change speed ΔML0 , and approached to the minimum operating frequency Mmin. When it does not arrive at the control restart temperature Tre at the time of arriving at the frequency Mmin, the operation of the compressor 12 is continued at the frequency Mmin for a first stand-by time t1 , and when the temperature Th is not returned even after the time t1 is elapsed, the compressor is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner equipped with a refrigerant circulation circuit (hereinafter simply referred to as an air conditioner), which is an inverter type air conditioner capable of changing the operating frequency of a compressor provided in the refrigerant circuit. Regarding control method.

[0002]

2. Description of the Related Art Conventionally, in an inverter type air conditioner having a refrigerant circulation circuit, it is possible to control the number of revolutions of the compressor provided in the refrigerant circulation circuit, that is, the operating frequency of the compressor, and to set a preset temperature. The operating frequency of the compressor is controlled according to the detected temperature difference from the indoor temperature. That is, in the inverter type air conditioner, the operating frequency of the compressor is controlled by PID control, fuzzy control, zone control or the like based on the temperature difference between the room temperature and the set temperature. Regardless of which control method is used, PID control, fuzzy control, or zone control, "matching the room temperature to the set temperature" is controlled with the highest priority, so when the room temperature reaches the set temperature, Alternatively, the compressor is stopped when the temperature exceeds the set temperature by a certain amount (thermo off).

For example, the one disclosed in Japanese Examined Patent Publication No. 4-47219 is equipped with a compressor whose operating frequency is controllable, and an off position for stopping the compressor when the room temperature is below a set temperature and the room temperature. When the temperature exceeds the preset temperature and reaches a predetermined temperature, a stable zone B for rotating the compressor at a low speed is formed between the on-position for restarting the stopped compressor and the stable zone B is exceeded. The variation range of the temperature difference between the room temperature and the set temperature in the region is divided into a plurality of zones C to F,
When the number of revolutions of the compressor corresponding to each zone C to F, that is, the operating frequency is set, and when the gradient of the indoor temperature change changes to the side distant from the set temperature, each zone B to F is set to the change width of the temperature difference. In the control device that shifts up to the side where the temperature rises, when the indoor temperature exceeds the OFF position and the gradient of the indoor temperature change changes to the side that moves away from the set temperature after the compressor stops, , Stability zone B
It is to stop the shift up.

[0004]

However, the above-described conventional inverter type air conditioner control method has the following problems. That is, when the room temperature is abruptly approaching the set temperature, such as when the room to be air-conditioned is small compared to the air conditioning capacity of the air conditioner, the operating frequency becomes lower one after another according to the temperature difference between the room temperature and the set temperature. It is instructed and controlled so as to lower the operating frequency of the compressor. However, when the operating frequency of the compressor is rapidly changed from a high operating frequency to a low operating frequency, the discharge pressure of the compressor cannot follow the change of the operating frequency, and the pressure on the discharge side of the compressor is high, The operating frequency of the compressor becomes low and the torque of the compressor becomes small, resulting in an overload condition. In order to prevent the occurrence of such an overload state, a sudden decrease in the operating frequency is controllably prevented, and therefore,
The thermostat turns off before the operating frequency drops sufficiently, that is, before the operating frequency drops to the minimum operating frequency, the room temperature reaches the set temperature and the thermostat turns off too far.
When the compressor stops, there is a problem that the compressor is not restarted even if the temperature difference of the thermo-on is reached until a predetermined time (for example, 3 minutes) elapses (see FIG. 8).

For example, in the zone control disclosed in Japanese Patent Publication No. 4-47219, if the changing speed of the operating frequency is limited to 2 Hz / sec in order to prevent the occurrence of the above-mentioned overload condition, the operating frequency is 60 Hz. When the operating frequency suddenly changes from the zone (E zone) to the operating frequency of 30 Hz (B zone), it takes 15 seconds for the operating frequency to reach 30 Hz. However, if the temperature difference between the room temperature and the set temperature reaches the thermo-off region (A zone) before the operating frequency reaches 30 Hz, the compressor will be stopped. Once the compressor is stopped, it is generally not restarted for about 3 minutes in order to protect the compressor, so even if the temperature difference of the thermo-on is reached before the 3 minutes have passed, the compressor will not restart. Had the problem that it could not be restarted.

An object of the present invention is to reduce the number of times of stopping the compressor as much as possible and to continuously operate the compressor regardless of which control method such as PID control, fuzzy control or zone control is used. It is to provide a control method of an inverter type air conditioner that can be performed.

[0007]

In order to achieve the above object, the control method of an inverter type air conditioner of the present invention is an inverter type air conditioner equipped with a compressor whose operating frequency M can be changed and controlled. , A thermo-off temperature Toff and a thermo-on temperature Ton having a predetermined temperature difference above and below the set temperature Ts, and a minimum operating frequency Mmin. Are set, and the indoor temperature Th exceeds the set temperature Ts.
Off-when reaching a temperature Toff, the operation when the frequency M is not reduced to the lowest operating frequency Mmin., The lowest operating frequency Mmin the operating frequency M with a predetermined off-time change rate .DELTA.M _LO.
After lowering the operating frequency M to the minimum operating frequency M
Even if the room temperature Th reaches the thermo-off temperature Toff by operating the compressor while keeping it at min., the operating frequency M of the compressor is not changed immediately without changing the compressor operating frequency M and the change speed ΔM _LO at the time of OFF. By decreasing with, the outlet temperature rises (during cooling or dry operation) or falls (during heating operation)
However, the indoor temperature distribution can be made uniform, comfortable air conditioning can be performed even near the thermo-off temperature Toff, and the reliability of the detected indoor temperature Th is improved. Further, the compressor can be stopped after confirming that the thermo-off state is sufficiently obtained, and the stop time until the compressor is restarted can be secured. When the room temperature Th does not return even after the preset first waiting time t ₁ is maintained by keeping the operating frequency M at the minimum operating frequency Mmin., The first waiting time t is stopped by stopping the compressor. _During the period ₁ , the compressor is operated at the minimum operating frequency Mmin., And it is possible to suppress the imbalance of air conditioning due to the position of the room based on the size of the room, that is, the variation in the room temperature Th. Since the off-time change speed ΔM _LO is smaller than the normal change speed ΔM, which is the change speed of the operating frequency in the normal control state, the operation frequency M of the compressor is gradually decreased to make the indoor temperature distribution uniform. And the comfortable air conditioning can be performed even near the thermo-off temperature Toff, and the detected indoor temperature T
The reliability of h is improved. In an inverter type air conditioner equipped with a compressor capable of changing and controlling an operating frequency M, a set temperature Ts and a thermo-off temperature Toff and a thermo-on temperature Ton having a predetermined temperature difference above and below the set temperature Ts.
And the minimum operating frequency Mmin. Are set, and when the indoor temperature Th exceeds the set temperature Ts and reaches the thermo-off temperature Toff, if the operating frequency M has already dropped to the minimum operating frequency Mmin. By stopping the compressor when it is in the thermo-off state after the elapse of the set second waiting time t ₂ , it is possible to stop the compressor after confirming that the thermo-off state has been sufficiently achieved, It is possible to secure the stop time until the compressor is restarted.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Referring to FIG. 5, an operation control device to which the present invention is applied will be described. Temperature setting means 1 for setting a set temperature Ts, indoor temperature detecting means 2 for detecting an indoor temperature Th, such as a thermostat, set temperature Ts and indoor temperature. A temperature difference calculating means 3 for calculating a temperature difference ΔT which is a difference from Th;
Operating frequency calculation means 4 for calculating the operating frequency M based on the temperature difference ΔT, the indoor temperature gradient change, and a predetermined zone.
A temperature difference storage means 5, an indoor temperature gradient change detection means 6 for detecting a change in the indoor temperature gradient based on the temperature difference ΔT, a zone storage means 7 storing predetermined zones, and a shift up means 8. A shift up stop means 9, an output frequency command means 10, and a frequency converter 11, and a compressor 12
It controls the operating frequency M of.

In zone control, zone storage means 7
A plurality of zones in which the operating frequency M is set and set according to the temperature difference ΔT stored in are stored, and which zone the indoor temperature Th is based on the temperature difference ΔT between the set temperature Ts and the room temperature Th. Check if there is a room temperature T
When h moves to a different zone, the operating frequency M in the destination zone is changed.

In the control of the present invention, the thermo-off temperature Toff, the control restart temperature Tre, and the thermo-on temperature Ton.
Is set in advance. The thermo-off temperature Toff is determined by changing the operating frequency M of the compressor at a predetermined change rate ΔM (eg, ΔM = 2).
Hz / 10 seconds), and when the frequency reaches the minimum frequency Mmin., The temperature at which the operation of stopping the compressor 12 is started after the waiting time t (for example, t = 6 minutes) has elapsed and the thermo-on temperature Ton is compressed. The temperature at which the machine is restarted, and the control restart temperature Tre is a temperature at which normal zone control that has been conventionally performed is transitioned to. These values differ between the cooling / drying operation and the heating operation, and are as follows.

[Cooling Operation and Dry Operation] Thermo-off temperature Toff: When the room temperature Th drops, the room temperature Th <set temperature Ts, and the thermo-off temperature Toff = set temperature Ts -1.0 deg, The operating frequency M of the compressor 12 is set to a predetermined off-time change speed ΔM _LO (for example,
ΔM _LO = 2 Hz / 10 seconds), and the first waiting time t ₁ (for example, t
_The compressor 12 is stopped after the elapse of ₁ = 6 minutes). Control restart temperature Tre: When the room temperature Th rises, the room temperature Th <the set temperature Ts, and the control restart temperature Tre = the set temperature Ts −0.5 deg. Thermo-on temperature Ton: When the room temperature Th rises, the room temperature Th> the set temperature Ts, and the thermo-on temperature T
The compressor 12 is restarted at on = set temperature Ts + 1.0 deg. Thermo-on temperature Ton> set temperature Ts> control restart temperature Tre> thermo-off temperature Toff.

[During heating operation] Thermo-off temperature Toff: When the room temperature Th rises, the room temperature Th> the set temperature Ts, and the thermo-off temperature Toff = set temperature Ts + 1.0 deg. Of the operating frequency M of the change rate ΔM _LO (for example,
ΔM _LO = 2 Hz / 10 seconds), and when the frequency reaches the minimum frequency Mmin., The compressor 12 is stopped after the first waiting time t ₁ (for example, t ₁ = 6 minutes) has elapsed. Control restart temperature Tre: When the room temperature Th falls, the room temperature Th> the set temperature Ts, and the control restart temperature Tre = the set temperature Ts + 0.5 deg. . Thermo-on temperature Ton: When the room temperature Th drops, the room temperature Th <set temperature Ts, and the thermo-on temperature T
The compressor 12 is restarted at on = the set temperature Ts −1.0 deg. Thermo-on temperature Ton <set temperature Ts <control restart temperature Tre <thermo-off temperature Toff holds.

The control operation will be described with reference to the flowchart of FIG. In any of the cooling operation, the dry operation, and the heating operation, the room temperature Th is set to the set temperature Ts.
As the indoor temperature Th approaches the set temperature Ts below (low temperature side) or above (high temperature side), the thermo-off temperature T
Until it reaches off, the operation is carried out under normal zone control, and the operating frequency of the compressor 12 is changed at a normal rate of change ΔM (eg
2Hz / sec).

The room temperature Th approaches the set temperature Ts from the high temperature side (during cooling operation or dry operation) or from the low temperature side (during heating operation), and further lowers the set temperature Ts below (low temperature side) or above (high temperature side). When the thermo-off temperature Toff is exceeded, the rate of change of the operating frequency M of the compressor 12 is changed from the normal change rate ΔM (for example, ΔM = 2 Hz / sec) to the off-time change rate ΔM _LO (for example, ΔM _LO = 2Hz / 10 seconds)
To gradually decrease the operating frequency M to approach the preset minimum operating frequency Mmin. For example, when a single rotary compressor is used as a compressor, the minimum operating frequency Mmin. = 30Hz, and when a twin rotary compressor is used, the minimum operating frequency Mmin. = 10Hz to 20Hz.
Hz.

When the air conditioning load is comparatively large, as shown in FIG. 2, the room temperature Th becomes lower than the thermo-off temperature Tof.
When the operating frequency M of the compressor 12 is not reduced to the minimum operating frequency Mmin. at that time, the operating frequency M of the compressor 12 is changed to the off speed change speed ΔM _LO (for example, ΔM _LO =
2 Hz / 10 seconds), but if the room temperature Th rises (during cooling operation or dry operation) or falls (during heating operation) before reaching the minimum operating frequency Mmin., And reaches the control restart temperature Tre. , Return to normal zone control. When returning to the normal zone control, the operating frequency M of the compressor is
The operation is carried out at the operating frequency M corresponding to the air conditioning load (that is, the set frequency Ms set in each zone).

When the air conditioning load is small, as shown in FIG. 3, the room temperature Th reaches the thermo-off temperature Toff, at which point the operating frequency M of the compressor 12 drops to the minimum operating frequency Mmin. If not, the operating frequency M of the compressor 12 is changed to the change speed ΔM _LO at the time of OFF (eg, ΔM _LO = 2 Hz /
Although it is decreased in 10 seconds), when the room temperature Th changes slowly and the control restart temperature Tre has not been reached when the minimum operating frequency Mmin. Is reached, the first waiting time t ₁ (for example,
t ₁ = 6 minutes), the compressor 12 at the minimum operating frequency Mmin.
Continue driving. First waiting time t ₁ (for example, t ₁ =
If the indoor temperature Th rises (during the cooling operation or the dry operation) or falls (during the heating operation) before reaching 6 minutes) and reaches the control restart temperature Tre, the normal zone control is restored. When returning to the normal zone control, the operating frequency M of the compressor is operated at the operating frequency M commensurate with the air conditioning load.

When the air-conditioning load is extremely small, as shown in FIG. 4, the room temperature Th becomes lower than the thermo-off temperature Tof.
When the operating frequency M of the compressor 12 is not reduced to the minimum operating frequency Mmin. at that time, the operating frequency M of the compressor 12 is changed to the off speed change speed ΔM _LO (for example, ΔM _LO =
2 Hz / 10 seconds), but the change in the room temperature Th is gradual, and when the control restart temperature Tre is not reached when the minimum operating frequency Mmin. Is reached, the first waiting time t ₁ (for example, t ₁ = 6 minutes), the operation of the compressor 12 is continued at the minimum operation frequency Mmin. First waiting time t ₁ (for example, t
_{If the} room temperature Th has not reached the control restart temperature Tre even after ( ₁ = 6 minutes), the thermostat is turned off (compressor stopped).
Let it. Room temperature Th with the compressor stopped
Reaches the thermo-on temperature Ton, the compressor 12 is restarted and the normal zone control is resumed. When returning to the normal zone control, the operating frequency M of the compressor is operated at the operating frequency M commensurate with the air conditioning load. Note that the room temperature Th is the control restart temperature Tre and the thermo-off temperature Toff.
And the first waiting time t ₁ (for example, t ₁ =
Even after 6 minutes), the compressor 12 is not stopped and the operation is continued at the minimum operation frequency Mmin.

The room temperature Th is the thermo-off temperature T.
When the operating frequency M of the compressor 12 has already dropped to the minimum operating frequency Mmin. when it reaches off, the second waiting time t ₂ (for example, t ₂ ≦ t ₁ , t ₂ = 4) is set in advance. Minutes)
Only continue to operate at the lowest operating frequency Mmin., When after the second waiting time t ₂ elapses even indoor temperature Th has not reached the control resumption temperature Tre is causing thermo-off (compressor stopped).

According to the above-mentioned configuration, even if the room temperature Th reaches the thermo-off temperature Toff, the operating frequency M of the compressor is changed to the off change speed ΔM _LO without immediately turning the thermo-off (the compressor is stopped). (For example, ΔM _LO = 2 Hz / 10 seconds) By gently lowering, the outlet temperature rises (during cooling or dry operation) or falls (during heating operation), and the indoor temperature distribution can be made uniform. Thermo-off temperature Toff
Comfortable air conditioning can be performed even in the vicinity, and the reliability of the detected indoor temperature Th is improved.

Further, it is possible to stop the compressor after confirming that the thermostat is sufficiently turned off, and it is possible to secure a stop time until the compressor is restarted.
In addition, the compressor is set to a predetermined first standby time t ₁ (for example, t
₁ = 6 minutes), the operating frequency M is set to the minimum operating frequency Mmi
By continuing the operation at n., it is possible to suppress the imbalance of the air conditioning due to the position in the room based on the size of the room, that is, the variation in the room temperature Th. Further, when returning to the normal zone control, the operating frequency M of the compressor is set to the operating frequency M corresponding to the air conditioning load (that is, the set frequency Ms.
), The stability of the room temperature Th thereafter is improved.

In the above embodiment, only zone control is used, but by adding fuzzy control or the like to normal zone control, it is possible to perform better air conditioning. Particularly, in zone control. When in the same zone, it is good to correct by a fuzzy control or the like at regular intervals. Further, the present invention can be applied basically regardless of the control method such as zone control, fuzzy control or PID control.

[0022]

EXAMPLE An example of the control operation to which the example of the present invention is applied will be described. As an example, assuming that a single rotary compressor is used as a compressor, a minimum operating frequency Mmin. = 30 Hz, which is a predetermined minimum operating frequency, is set, and the control range of the operating frequency M is operated during cooling operation and dry operation. Frequency M = 30Hz-85Hz, cooling rated operating frequency Ms = 68Hz, operating frequency M = during heating operation
36 Hz-135 Hz, cooling rated operating frequency Ms = 87 Hz. When a twin rotary compressor is used, the minimum operating frequency Mmin. = 10Hz to 20Hz.

FIG. 6 shows an example of zones during the cooling operation and the dry operation. Thermo-off temperature Toff: Temperature difference ΔT = -1.0 deg as the thermo-off temperature Toff when the room temperature Th falls.
Then, the compressor 12 is stopped. Control restart temperature Tre: When the indoor temperature Th rises, the control restart temperature Tre shifts to normal zone control with a temperature difference ΔT = −0.5 deg. Thermo-on temperature Ton: When the indoor temperature Th rises, the compressor 12 is restarted with the temperature difference ΔT = + 1.0 deg as the thermo-on temperature Ton. Zone a: +2.0 deg when the room temperature Th drops <Temperature difference Δ
T, when the indoor temperature Th rises, +2.5 deg <temperature difference ΔT,
Set frequency Ms = 85Hz. Zone b: +1.5 deg <temperature difference Δ when the room temperature Th drops
T ≦ + 2.0 deg, +2.0 deg when rising <Temperature difference ΔT ≦ +
At 2.5 deg, set frequency Ms = 68Hz. c zone: +1.0 deg <temperature difference Δ when the room temperature Th drops
T ≦ + 1.5 deg, +1.5 deg when rising <Temperature difference ΔT ≦ +
At 2.0 deg, set frequency Ms = 53Hz. d zone: +0.5 deg when the room temperature Th drops <temperature difference Δ
T ≦ + 1.0 deg, +1.0 deg when rising <Temperature difference ΔT ≦ +
Setting frequency Ms = 42Hz at 1.5deg. e zone: 0 deg when the room temperature Th decreases <temperature difference ΔT ≤
+0.5 deg, +0.5 deg when rising <Temperature difference ΔT ≤ +1.0
At deg, set frequency Ms = 36Hz. f zone: -0.5 deg <temperature difference Δ when the room temperature Th drops
T ≤ 0 deg (indoor temperature Th = set temperature Ts), when rising 0 deg <temperature difference ΔT ≤ +0.5 deg, set frequency Ms =
30Hz. g zone: -1.0 deg <temperature difference Δ when the room temperature Th drops
T ≦ −0.5 deg, −0.5 deg when rising <Temperature difference ΔT ≦ 0
At deg, set frequency Ms = 30Hz. h zone: Temperature difference ΔT ≦ −1.0 de when the room temperature Th drops
g, ΔT ≦ −0.5 deg when rising, set frequency Ms = minimum frequency Mmin. (= 30 Hz), but room temperature Th ≦ thermo-off temperature Toff (that is, temperature difference ΔT ≦ −1.0 deg) waits first When the time t ₁ continues, the compressor 12 turns off.

Explaining the operation in the cooling operation or the dry operation, when the room temperature Th is sufficiently high and the zone a is in operation, the compressor is operated at the operation frequency M = 85 Hz, that is, at the maximum capacity, and the room temperature Th is lowered. Then, when the operation shifts to the b zone, the compressor is operated by changing the operating frequency to M = 68 Hz, that is, the cooling capacity is lowered. Similarly, the room temperature Th
Continues to fall and reaches the operating frequency M of the compressor in sequence from the b zone to the c zone, the d zone, the e zone, and the g zone.
From M = 68Hz set in each zone to 53Hz, 42Hz, 36
It is to change to each set frequency Ms of Hz and 30Hz.
At this time, the normal change speed ΔM (for example, ΔM = 2 Hz / sec)
Change the operating frequency M with.

When the indoor temperature Th further decreases and the h zone, that is, the indoor temperature Th reaches the thermo-off temperature Toff, the change speed of the operating frequency M of the compressor is changed at the time of off which is smaller than the normal change speed ΔM. Speed ΔM _LO (eg ΔM
Change to _LO = 2Hz / 10 seconds) and gradually lower. The room temperature Th decreases, and the room temperature Th is equal to the thermo-off temperature T.
When turned off, the operating frequency M is the minimum operating frequency Mmin.
= 30Hz is not reached (M> Mmin.), The operating frequency M is the off speed change speed ΔM _LO and the minimum operating frequency Mmin.
Continue decreasing until reaching = 30Hz.

The operating frequency M is the minimum operating frequency Mmin. = 30
The room temperature Th rises before reaching Hz, the room temperature Th shifts from the h zone to the g zone, and the control restart temperature Tre (=
When Ts-0.5 deg) is reached, the normal zone control is started and the compressor sets the frequency Ms = 30 corresponding to the air conditioning load.
Driven at Hz. If the room temperature Th does not rise and the room temperature Th does not rise to the control restart temperature Tre even if the operating frequency M drops to the minimum operating frequency Mmin. = 30 Hz,
During the first standby time t ₁ (for example, 6 minutes), the operation is continued at the operating frequency M at the minimum operating frequency Mmin.
Before the waiting time t ₁ (for example, 6 minutes) elapses, the room temperature T
When h rises to the control restart temperature Tre, the normal zone control is performed.

If the room temperature Th has not risen to the control restart temperature Tre even after the lapse of the first waiting time t ₁ (for example, 6 minutes), the thermostat is turned off to stop the compressor. When the compressor is stopped by turning the thermo off, the room temperature T
When h rises to reach the thermo-on temperature Ton (that is, in the d zone), the thermo-on, that is, the compressor is restarted, and at the same time, the normal zone control is performed. When the room temperature Th is between the thermo-off temperature Toff and the control restart temperature Tre, the operation frequency M of the compressor is kept at the minimum operation frequency Mmin. = 30 Hz, and the compressor is not stopped. Is.

FIG. 7 shows an example of zones during heating operation. Thermo-off temperature Toff: Temperature difference ΔT = + 1.0 deg as thermo-off temperature Toff when the room temperature Th rises
Then, the compressor 12 is stopped. Control restart temperature Tre: When the indoor temperature Th is lowered, the control restart temperature Tre is changed to the normal zone control with a temperature difference ΔT = + 0.5 deg. Thermo-on temperature Ton: When the indoor temperature Th drops, the compressor 12 is restarted with the temperature difference ΔT = -1.0 deg as the thermo-on temperature Ton. Zone a: Temperature difference ΔT ≦ −2.5 de when room temperature Th rises
g, temperature difference ΔT ≤ -3.0 deg at the time of falling, set frequency M
s = 135Hz. Zone b: -2.5 deg <temperature difference Δ when room temperature Th rises
T ≦ −2.0 deg, −3.0 deg when descending <Temperature difference ΔT ≦ −
At 2.5 deg, the set frequency Ms = 115Hz. c zone: -2.0 deg <temperature difference Δ when room temperature Th rises
T ≦ −1.5 deg, −2.5 deg when descending <Temperature difference ΔT ≦ −
At 2.0 deg, set frequency Ms = 95Hz. d zone: -1.5 deg <temperature difference Δ when room temperature Th rises
T ≦ −1.0 deg, −2.0 deg when descending <Temperature difference ΔT ≦ −
Set frequency Ms = 75Hz at 1.5deg. e zone: -1.0deg <increase of room temperature Th <temperature difference Δ
T ≦ −0.5 deg, −1.5 deg when descending <Temperature difference ΔT ≦ −
At 1.0 deg, set frequency Ms = 60Hz. f zone: -0.5 deg <temperature difference Δ when room temperature Th rises
T ≤ 0 deg (indoor temperature Th = set temperature Ts), -1.0 deg <temperature difference ΔT ≤ -0.5 deg when set, and set frequency M
s = 45Hz. g zone: 0 deg when the room temperature Th rises <temperature difference ΔT ≤
+0.5 deg, -0.5 deg when descending <Temperature difference ΔT ≤ 0 deg
Then, set frequency Ms = 36Hz. h zone: +0.5 deg <temperature difference Δ when room temperature Th rises
T ≤ +1.0 deg, 0 deg when descending <Temperature difference ΔT ≤ +0.5
At deg, set frequency Ms = 36Hz. i zone: Temperature difference ΔT ≧ + 1.0 de when the room temperature Th rises
g, temperature difference ΔT ≥ +0.5 deg at the time of falling, set frequency M
s = minimum frequency Mmin. (= 30Hz), but room temperature Th ≥
Thermo-off temperature Toff (Temperature difference ΔT ≧ + 1.0 de
When g) continues for the first waiting time t ₁ , the compressor 12 is turned off.

Explaining the operation in the heating operation, when the room temperature Th is sufficiently low and the zone a is in operation, the compressor is operated at an operating frequency M = 135 Hz (maximum capacity), and the room temperature Th rises to the zone b. When the shift is made, the compressor is operated by changing the operating frequency to M = 115 Hz, that is, the heating capacity is reduced. Similarly, when the indoor temperature Th continues to rise and reaches from zone b to zone c, zone d, zone e, zone g, and zone h, the operating frequency M of the compressor is set to M = 115 Hz set in each zone. Or 95Hz, 75Hz, 60Hz, 45Hz,
The set frequency Ms is changed to 36 Hz. At this time, the operating frequency M is changed at a normal change speed ΔM (eg, ΔM = 2 Hz / sec).

When the indoor temperature Th further rises and the i-zone, that is, the indoor temperature Th reaches the thermo-off temperature Toff, the change speed of the operating frequency M of the compressor is changed at the time of off which is smaller than the normal change speed ΔM. Speed ΔM _LO (eg ΔM
Change to _LO = 2Hz / 10 seconds) and gradually lower. Room temperature Th rises and room temperature Th = Thermo-off temperature T
When turned off, the operating frequency M is the minimum operating frequency Mmin.
= 30Hz is not reached (M> Mmin.), The operating frequency M is the off speed change speed ΔM _LO and the minimum operating frequency Mmin.
Continue decreasing until reaching = 30Hz.

The operating frequency M is the minimum operating frequency Mmin. = 30
The indoor temperature Th decreases before reaching Hz, the indoor temperature Th shifts from the i zone to the h zone, and when the control restart temperature Tre is reached, it shifts to normal zone control and the compressor matches the air conditioning load. It operates at the set frequency Ms = 30Hz. The indoor temperature Th does not fall and the operating frequency M is the minimum operating frequency M.
Even if it decreases to min. = 30Hz, the room temperature Th is the control restart temperature T
If it does not fall to re, the operating frequency M is changed to the minimum operating frequency M during the first waiting time t ₁ (for example, 6 minutes).
The operation is continued at min. = 36 Hz, and the room temperature Th is the control restart temperature Tr before the first waiting time t ₁ (for example, 6 minutes) has elapsed.
When it descends to e, it shifts to normal zone control.

If the room temperature Th has not dropped to the control restart temperature Tre even after the lapse of the first waiting time t ₁ (for example, 6 minutes), the thermostat is turned off to stop the compressor. When the compressor is stopped by turning the thermo off, the room temperature T
When h decreases to reach the thermo-on temperature Ton (that is, in the d zone), the thermo-on, that is, the compressor is restarted, and at the same time, the normal zone control is performed. When the room temperature Th is between the thermo-off temperature Toff and the control restart temperature Tre, the operation frequency M of the compressor is kept at the minimum operation frequency Mmin. = 36 Hz, and the compressor is not stopped. Is.

[0033]

Since the present invention is constructed as described above, it has the following effects. The set temperature Ts, the thermo-off temperature Toff and the thermo-on temperature Ton having a predetermined temperature difference above and below the set temperature Ts, and the minimum operating frequency M
min. and when the room temperature Th exceeds the set temperature Ts and reaches the thermo-off temperature Toff, if the operating frequency M has not dropped to the minimum operating frequency Mmin. By lowering the operating frequency M to the minimum operating frequency Mmin. With ΔM _LO , and then operating the compressor while maintaining the operating frequency M at the minimum operating frequency Mmin.
Even if the room temperature Th reaches the thermo-off temperature Toff, the operating temperature M of the compressor is decreased at the off-time change speed ΔM _LO without stopping the compressor immediately, so that the blow-out temperature rises (cooling or drying). During operation) or lowering (during heating operation), the indoor temperature distribution can be made uniform, comfortable air conditioning can be performed even near the thermo-off temperature Toff, and the reliability of the detected indoor temperature Th can be achieved. Is improved. In addition, the compressor can be stopped after confirming that the thermo-off state has been sufficiently achieved.
It is possible to secure the stop time until the compressor is restarted. Hold the operating frequency M at the minimum operating frequency Mmin.
Even if the preset first waiting time t ₁ elapses, the room temperature T
If h does not return, stop the compressor,
By operating the compressor at the minimum operation frequency Mmin. During the first standby time t ₁ , it is possible to suppress the imbalance of air conditioning depending on the position of the room based on the size of the room, that is, the variation in the room temperature Th. Since the off-time change speed ΔM _LO is smaller than the normal change speed ΔM that is the change speed of the operating frequency in the normal control state, the operating frequency M of the compressor is reduced.
Is gradually reduced to make the indoor temperature distribution uniform, and comfortable air conditioning can be performed even near the thermo-off temperature Toff, and the reliability of the detected indoor temperature Th is improved. In particular, since the blowout temperature changes gently, the user does not feel uncomfortable and comfortable air conditioning can be performed. In an inverter type air conditioner equipped with a compressor capable of changing and controlling an operating frequency M, a set temperature Ts and a thermo-off temperature Toff and a thermo-on temperature Ton having a predetermined temperature difference above and below the set temperature Ts.
And the minimum operating frequency Mmin. Are set, and when the indoor temperature Th exceeds the set temperature Ts and reaches the thermo-off temperature Toff, if the operating frequency M has already dropped to the minimum operating frequency Mmin. By stopping the compressor when it is in the thermo-off state after the elapse of the set second waiting time t ₂ , it is possible to stop the compressor after confirming that the thermo-off state has been sufficiently achieved, It is possible to secure the stop time until the compressor is restarted.

[Brief description of drawings]

FIG. 1 is a flowchart showing the operation of the present invention.

FIG. 2 is a time chart showing the operation of the present invention.

FIG. 3 is a time chart showing a different operation of the present invention.

FIG. 4 is a time chart showing still another operation of the present invention.

FIG. 5 is a block diagram showing an example of an operation control device to which the present invention is applied.

FIG. 6 is an explanatory diagram showing a control mode of the compressor according to a temperature difference between an indoor temperature and a set temperature during a cooling operation or a dry operation.

FIG. 7 is an explanatory diagram showing a control mode of the compressor according to a temperature difference between an indoor temperature and a set temperature during a heating operation.

FIG. 8 is a time chart showing a conventional control operation.

[Explanation of symbols]

1 temperature setting means, 2 indoor temperature detecting means, 3 temperature difference calculating means, 4 operating frequency calculating means, 5 temperature difference storing means, 6 indoor temperature gradient change detecting means, 7 zone storing means,
8 shift up means 9 shift up stop means, 10 output frequency command means,
11 Frequency converter 12 Compressor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiro Nishida 93 No. Edo-cho, Chuo-ku, Kobe-shi, Hyogo In stock company Noritsu

Claims (4)

[Claims] 1. An inverter type air conditioner equipped with a compressor capable of changing and controlling an operating frequency M, wherein a set temperature T
s, a thermo-off temperature Toff and a thermo-on temperature Ton having a predetermined temperature difference above and below the set temperature Ts, and a minimum operating frequency Mmin. are set, and the room temperature Th exceeds the set temperature Ts. When the operating frequency M does not decrease to the minimum operating frequency Mmin. When the off temperature Toff is reached, after the operating frequency M is decreased to the minimum operating frequency Mmin. At a predetermined off-time change speed ΔM _LO , A method for controlling an inverter type air conditioner, which comprises operating a compressor while maintaining an operating frequency M at a minimum operating frequency Mmin. 2. The operating frequency M is kept at the minimum operating frequency Mmin., And if the room temperature Th does not return even after the preset first waiting time t ₁ , the compressor is stopped. The method for controlling an inverter type air conditioner according to claim 1. 3. The off change rate ΔM _LO is a normal change rate Δ that is a change rate of the operating frequency in a normal control state.
It is smaller than M, The control method of the inverter type air conditioner of Claim 1 or 2 characterized by the above-mentioned. 4. An inverter type air conditioner equipped with a compressor capable of changing and controlling an operating frequency M, wherein a set temperature T
s, a thermo-off temperature Toff and a thermo-on temperature Ton having a predetermined temperature difference above and below the set temperature Ts, and a minimum operating frequency Mmin. are set, and the room temperature Th exceeds the set temperature Ts. When the operating temperature M has already dropped to the minimum operating frequency Mmin. When the off temperature Toff is reached, the compressor is stopped when the thermostat is off after the preset second waiting time t _2. A method for controlling an inverter type air conditioner characterized by: