JP2500564B2 - Air conditioner automatic wind speed control system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic wind speed control system for an air conditioner for controlling the amount of air blown from an indoor heat exchanger in the air conditioner.

[0002]

2. Description of the Related Art An indoor heat exchanger equipped with an indoor fan,
In an air conditioner in which a compressor, an outdoor heat exchanger, and an expansion valve are sequentially connected, refrigerant is circulated by the compressor, and cooling or heating is performed using a cooling cycle in which compression and expansion are repeated, the compressor is operated to perform cooling or heating. When the room temperature reaches the set temperature during operation, the compressor is stopped (turned off) to stop the refrigerant circulation in the cooling cycle, and the room temperature is higher than the set temperature (during cooling operation) or the set temperature. Generally, a method of restarting (turning on) the compressor when the temperature becomes lower (during heating operation) is used.

Conventionally, in an air conditioner using a method of turning on / off the compressor, when the compressor is turned off, the indoor fan is operated from high speed to low speed, that is, indoor air blowing is strong to weak (or strong → medium). There is an automatic wind speed control method that gradually switches from low speed to high speed when the compressor is turned on, that is, gradually changes the indoor air blowing from weak to strong (or weak → medium → strong) when the compressor is turned on. Known (for example, Shoukai 57-
(See Japanese Patent No. 58826).

[0004]

However, in the above-mentioned conventional automatic wind speed control system, the amount of air blown by the indoor fan is in two stages (or 3) depending on whether the compressor is on or off.
It changes rapidly (steps) (see FIG. 11), and the user feels uncomfortable because the temperature changes stepwise regardless of how the indoor temperature changes, and when the air flow rate suddenly decreases,
There is a problem in that the sensible temperature changes depending on the strength of the wind hitting the body, such as a feeling that the room temperature is high.

An object of the present invention is to use fuzzy inference to perform continuous air flow rate control in response to changes in room temperature and to quickly respond to disturbances such as changes in set temperature. An object of the present invention is to provide an automatic wind speed control system for an air conditioner that can perform comfortable air conditioning.

[0006]

To achieve the above object, an automatic wind speed control system for an air conditioner according to the present invention is an indoor heat exchanger equipped with an indoor fan, a compressor, an outdoor heat exchanger and an expansion device. In an air conditioner that is configured by sequentially connecting valves and turns the compressor on and off according to the indoor temperature, the temperature difference between the set temperature and the indoor temperature and the indoor temperature change rate are detected and detected at each sampling time. The temperature difference and the indoor temperature change rate are input, and the fuzzy inference calculation is used to calculate the control amount of the indoor fan as the airflow index, and the command signal ( In particular, when the set temperature change signal) is input, the room temperature data is immediately input and corrected according to the elapsed time from the start of the previous control operation. Since it is inferred and controlled using the corrected indoor temperature change rate, it is possible to continuously control the amount of air blown by the fan of the indoor heat exchanger, and to give a feeling of strangeness when the amount of air blow changes in response to room temperature changes. In addition, the change in room temperature as the sensible temperature can be suppressed to a minimum, the control response speed is increased, and the desired set temperature can be reached quickly.

[0007]

EXAMPLES Examples of the present invention will be described. As an example of fuzzy reasoning adopted in the automatic wind speed control system of the air conditioner of the present invention, a case where a command signal is not input during the sampling time will be described based on the flowchart (algorithm) of FIG. Is measured by a sampling timer, the room temperature Tm at the time of sampling time Hs (for example, 3 minutes) is taken in as data (room temperature sampling), and the temperature difference | ΔT | between the preset temperature Ts and the room temperature Tm is absolute. Calculate as a value. | ΔT | = | Ts−Tm | Based on the calculated temperature difference | ΔT |, the input membership value is obtained by the membership function shown in FIG. 2 to obtain the temperature difference fuzzy data. In FIG. 2, ZO (just right), NS (somewhat different), NM (some difference)
And NB (the difference is large).

Further, the difference ΔTm between the indoor temperature Tm ₁ detected last time and the indoor temperature Tm detected this time is expressed in unit time Δt.
The room temperature change rate (hereinafter referred to as the change rate) D obtained by dividing is calculated . Here, the unit time Δt is the reference regardless of the actual value.
The value Δt = 1. D = ΔTm / Δt = Tm ₁ −Tm Based on the calculated change rate D, the input membership value is obtained by the membership function shown in FIG. 3, and the change rate fuzzy data is obtained. In FIG. 3, the rate of change D has three levels of N (changes negatively), ZO (no change), and P (changes positively).

From the temperature difference fuzzy data and the rate of change fuzzy data, an output membership value is obtained by referring to a preset rule. The rule in this embodiment is
As shown as a matrix in FIG. 4, 12 types are defined, and the output membership function W has four stages of ZO (light wind), PS (weak wind), PM (medium wind), and PB (strong wind). That is, the control rule is R1: if the temperature difference | ΔT | becomes close to zero, that is, | ΔT
If | = ZO (just right) and the change rate D = N (changes to negative), the output membership function W becomes ZO (light breeze). In other words, the room temperature Tm becomes close to the set temperature Ts, the temperature difference | ΔT | between the set temperature Ts and the room temperature Tm is just right, and the rate of change D changes negatively, that is, the direction in which the room temperature Tm decreases. When it changes to, the blast is a breeze. (R1: If | ΔT | is ZO and Dis
N, then W is ZO) R2: If the temperature difference | ΔT | = NS (there is a slight difference) and the rate of change D = N (changes to negative), then the output membership function W is PS (Weak wind). (R2: If | ΔT | is NS and Dis
N, then Wis PS) Similarly, twelve control rules up to R12 are shown. In FIG. 5, the output membership function W is
The output membership value (grade) for the air volume index is shown.

The temperature difference fuzzy data and the rate of change fa
G data, referring to the above control rule, min.
Calculate the output membership value by composition and use it as ma
x. The output membership composite value obtained by combining is subjected to one-point calculation, that is, inverse fuzzy conversion. In addition, the calculation formula for performing the inverse fuzzy conversion is a gravity center calculation formula f _w = ∫f (x)
· X dx / ∫f by modifying the (x) dx, it is calculated by _{W 0 = (a · α +} b · β + c · γ + d · δ) / (a + b + c + d). However, in FIG. 5, a is an output membership composite value (grade) of ZO, b is an output membership composite value (grade) of PS, c is an output membership composite value (grade) of PM, and d is an output of PB. is a membership composite value (grade), α, β, γ, δ in advance
It is a predetermined weighting coefficient, for example α = 0, β
= 5, γ = 10, δ = 15
Weight it .

[0011] W obtained is reverse fuzzified by the arithmetic expression ₀ is the air mass index, air volume table shown in FIG. 6, or fan speed 7 - becomes an address in the graph of the address, the required fan The number of rotations is obtained, and a control signal corresponding to the obtained number of rotations is output.
In this embodiment, the air volume index has 16 stages, and a continuous change in the air volume can be obtained because fine rotation speed control is performed.

As an example, the sampling time H _S = 3 minutes, the set temperature Ts = 26 ° C., the present room temperature Tm = 22.9 ° C., and the previous room temperature Tm ₁ = 21.5 ° C., the temperature difference | ΔT | = 2.1, change rate D = +1.4. The membership value of the temperature difference | ΔT | obtained from Fig. 2 is ZO (2.1) = 0, NS as temperature difference fuzzy data.
(2.1) = 1.0, NM (2.1) = 0, NB (2.1) = 0
Is obtained. Further, the membership value of the rate of change D obtained from FIG. 3 is N (+
1.4) = 0, ZO (+1.4) = 0, P (+1.4) = 1.0
Is obtained.

By referring to the control rule (see FIG. 5) for all of the temperature difference fuzzy data and the rate of change fuzzy data, the following values are obtained. R1: ZO = 0 R5: ZO = 0 R9: PS = 0 R2: PS = 0 R6: PS = 0 R10: PM = 1.0 R3: PS = 0 R7: PM = 0 R11: PB = 0 R4: PM = 0 R8: PB = 0 R12: PB = 0 The output membership value is min. Required by synthesis. For example, for rule R2, the NS grade of the temperature difference fuzzy data is 1.0, and the N grade of the change rate fuzzy data is 0. Therefore, the smaller of these grade values is the grade of the output membership value PS. Becomes That is, PS = 0. To organize this, out of each
Strength membership values ZO, PS, PM, PB grades
When the Ru demand, the ZO = 0, PS = 0, PM = 0,1.0, PB = 0. That is, the output membership value ZO is R1 and
The grade value can be obtained from the two control rules of R5,
Since the values are both 0, the grade of ZO is 0 after all.
Only. Similarly, PS is R2, R3, R6, R9
The grade value can be obtained from the four control rules of
Since both values are 0, after all, PS grade is 0
It is. Regarding PM, there are three types of R4, R7 and R10.
The grade value is obtained from the control rule, but R4 and R7
Are both 0 and the grade obtained from R10 is 1.0
After all, PM grades are 0 and 1.
It will have multiple values of zero. For PB, R
Grade value from three control rules of 8, R11, R12
Is obtained, but its values are all 0, so in the end, Z
The grade of O is 0 only. Then, PM = 0, 1.
If there are 0 and multiple values, take the maximum value (m
ax. (Combination), the combined output membership values are ZO: a = 0, PS: b = 0, PM: c = 1.0, and PB: d = 0.

[0014] Next, when the reverse fuzzy of the above-mentioned, above
As a = 0, b = 0, c = 1.0, d = 0, the weighting factors are α = 0, β = 5, γ = 10, δ =
Assuming 15, W ₀ = (0 × 0 + 0 × 5 + 1.0 × 10
+ 0 × 15) / (0 + 0 + 1.0 + 0) = 10,
If this value is used as the air flow rate table of FIG. 6 or the address value of the fan rotation speed-address graph of FIG. 7 is obtained, the fan rotation speed is 1,400 rpm (medium air), so the fan rotation speed is 1,400 rpm. To control.

By controlling using such a fuzzy inference, the amount of air blown by the fan of the indoor heat exchanger can be continuously controlled, and the airflow amount corresponding to the change in room temperature does not feel uncomfortable. A change in room temperature as a sensible temperature can be suppressed to a minimum (see FIG. 10).

Next, the control operation in the automatic wind speed control system of the air conditioner of the present invention will be described with reference to the flow chart of FIG. When the command signal (change signal of the set temperature Ts, etc.) is not transmitted from the remote controller, the elapsed time H from the start of the previous control operation is measured, and the elapsed time H is the sampling time Hs (for example, 3 minutes). 9), the control based on the previous control operation is continued and the elapsed time H is continuously measured. When the elapsed time H exceeds the sampling time Hs (3 minutes), the indoor temperature Tm is detected and input at each sampling time Hs (3 minutes) based on the set temperature Ts used in the previous control operation, and the control is performed. Start operation.

When there is a command signal from a remote controller or the like, regardless of whether or not the set temperature Ts is changed,
The set temperature Ts at that time is newly input, and the control operation is started based on this new set temperature Ts. Note that the command signal from the remote controller, etc. is limited to only the change signal of the set temperature Ts, and only when the set temperature Ts is changed, the new set temperature Ts is input to start the control operation, and the change signal of the wind direction etc. If the set temperature Ts has not been changed by itself, the control operation is continued assuming that there is no command signal.

The room temperature Tm is detected and input (indoor sampling), and the temperature difference | ΔT | between the set temperature Ts calculated as an absolute value and the room temperature Tm is input to the X register. X = | ΔT | = | Ts−Tm | The difference ΔTm between the indoor temperature Tm ₁ previously detected in the Y register and the indoor temperature Tm detected this time is calculated as the unit time Δt (actual value
Change rate is divided by without Delta] t = 1) related to D (D = Tm ₁ -
Tm) is the ratio (H / H ) of the elapsed time H to the sampling time Hs (3 minutes) from the time when the previous indoor temperature Tm ₁ at the time of inputting a change signal of the set temperature Ts or the like is detected.
The correction change rate Dc corrected in s) is input. Y = Dc = D × Hs / H = (Tm ₁ −Tm) × Hs / H In the above equation, it is assumed that the indoor temperature Tm changes linearly or in proportion to the elapsed time, and the elapsed time H The amount of change in the room temperature Tm at is corrected to the amount of change in the room temperature Tm per sampling time Hs.

The above fuzzy inference is performed from the X register and the Y register. Based on X = | ΔT |, the input membership value is obtained, and four stages of temperature differences, ZO (just right), NS (slightly different), NM (difference) and NB (large difference) Ask for fuzzy data. Also,
Based on Y = Dc, the input membership value is obtained by the membership function shown in FIG. 3, and three levels of N (changing to negative), ZO (no change) and P (changing to positive) are obtained. Obtain the corrected change rate fuzzy data.

From the temperature difference fuzzy data and the change rate fuzzy data, the output membership value is obtained by referring to the above-mentioned set control rule (see FIG. 4 or 5). Referring to the control rules for all fuzzy data, input membership data (X = | ΔT | and Y =
Based on the output membership value obtained from Dc), min.-max. Combination is performed, and the obtained output membership combined value is subjected to one-point calculation, that is, inverse fuzzy conversion, to calculate the air volume index W ₀ . W ₀ = (a ・ α + b ・ β + c ・ γ + d ・ δ) / (a + b
+ C + d) where a is the combined output membership value of ZO and b is PS
Output membership composite value c, PM output membership composite value d, PB output membership composite value D
And α, β, γ, δ are output membership functions Z
It is a wind power index when O, PS, PM, and PB take maximum values. The wind power index W ₀ becomes the address in the air volume table shown in FIG. 6 or the fan rotation speed-address graph shown in FIG. 7, and the required fan rotation speed is obtained. The measurement of the elapsed time H is reset to zero and restarted, and at the same time, the control signal according to the obtained rotation speed is output to control the rotation speed of the indoor fan.

With the above configuration, the rate of change D of the room temperature is obtained and inferred for each fixed sampling time Hs (3 minutes), so that it is possible to continuously change the air flow rate corresponding to the room temperature change. At the same time, before the sampling time Hs (3 minutes) has elapsed after the previous control operation was started, for example, the elapsed time H shorter than the sampling time Hs (3 minutes)
_{If a} command signal (especially the set temperature Ts change signal) is input by operating the remote controller or the like when ₁ and H _{2 have} elapsed (H ₁ <Hs, H ₂ <Hs) (see FIG. 9), immediately By inputting the temperature Tm data and inferring and using the correction change rate Dc corrected according to the elapsed time H from the start of the previous control operation as described above, the control response speed becomes large and the desired set temperature is reached. It can be reached quickly (see FIG. 10).

[0023]

Since the present invention is constructed as described above, it has the following effects. By calculating the control amount of the indoor fan by the fuzzy inference calculation from the temperature difference between the set temperature and the indoor temperature and the indoor temperature change rate, it is possible to continuously control the amount of air blown by the fan of the indoor heat exchanger. In addition, it is possible to minimize the change in the room temperature as the sensible temperature without giving an uncomfortable feeling when the air volume changes corresponding to the change in the room temperature. When a signal (particularly, a set temperature change signal) is input, the room temperature data is immediately input, and it is inferred and controlled using the correction change rate corrected according to the elapsed time from the start of the previous control operation. Therefore, the control response speed becomes high, and the desired set temperature can be reached quickly.

[Brief description of drawings]

FIG. 1 is a flowchart (algorithm) of fuzzy inference according to the present invention.

FIG. 2 is a membership function of fuzzy data with respect to a temperature difference between a set temperature and an indoor temperature according to the present invention.

FIG. 3 is a membership function of fuzzy data with respect to a room temperature change rate according to the present invention.

FIG. 4 is a matrix of control rules according to the present invention.

FIG. 5 is a membership function of fuzzy data with respect to the air volume index according to the present invention.

FIG. 6 is an example of an air volume table according to the present invention.

FIG. 7 is a graph of fan rotation speed with respect to an air volume index according to the present invention.

FIG. 8 is a flowchart of a control operation according to the present invention.

FIG. 9 is an explanatory diagram of inference timing of control operation according to the present invention.

FIG. 10 is a time chart of a control operation according to the present invention.

FIG. 11 is a time chart of control operation according to a conventional method.

Claims (1)

(57) [Claims] 1. An indoor heat exchanger equipped with an indoor fan,
An air conditioner that connects a compressor, an outdoor heat exchanger, and an expansion valve in order, and turns the compressor on and off according to the indoor temperature, detects the temperature difference between the set temperature and the indoor temperature, and the indoor temperature change rate. Then, the detected temperature difference and the indoor temperature change rate are input, the control amount of the indoor fan is calculated as an airflow index by fuzzy inference calculation, and a command signal is input after the start of the previous control operation and before the sampling time elapses. In this case, the indoor temperature data is immediately input, and it is inferred by using the corrected indoor temperature change rate corrected according to the elapsed time from the start of the previous control operation, and the air conditioner is automatically controlled. Wind speed control method.