KR0176691B1 - Temp.control method and device thereof in ref. - Google Patents

Abstract

The present invention relates to a refrigerator which controls cold air discharge speed in accordance with a cold air discharge direction into a refrigerating chamber and a rotational speed of a blower fan according to a stationary angle position of a rotary vane, A temperature control method, and a temperature control apparatus. A method for controlling a temperature of a refrigerator according to the present invention includes the steps of: constructing a fuzzy model for inferring a portion having the highest temperature among various portions in a refrigerating chamber; Measuring a temperature change at a predetermined location in the refrigerating chamber; Calculating an optimal equilibrium angular position at which the rotary blade must stop toward an inferred position and an optimal equilibrium velocity at which the blower fan should be rotated by fuzzy inference by the fuzzy model according to the measured value of the temperature change, Wow; Controlling the rotational speed of the blowing fan according to the equilibrium speed and controlling the stopping angle position of the rotary vane according to the equilibrium angular position. Accordingly, the temperature value of each part of the refrigerating compartment can be precisely deduced with only a small number of temperature sensors, and the cold air distribution according to the distance and the direction can be performed by adjusting the rotation speed of the blowing fan and the non- Lt; / RTI > can be kept even without a particular bias.

Description

A method of controlling the temperature of the refrigerator by controlling the speed of the blowing fan and the stop angle position of the rotating blades and the temperature control device of the refrigerator

The present invention relates to a method of controlling the temperature of a refrigerator by controlling the speed of a blowing fan and a stop angle position of a rotating blade and a method of controlling the temperature of the refrigerator by controlling a stop angle of a rotary blade in a refrigerator toward a deduced position in fuzzy inference The cold air discharge angle is adjusted and the cold air discharge speed from the blower fan is adjusted to distribute the cold air according to the distance to uniformly control the temperature in the hearth.

In a refrigerator, particularly a large refrigerator, the load of foods and the like contained in the refrigerating chamber is different depending on each part of the refrigerating chamber, so that it is difficult to keep the temperature distribution in the refrigerating chamber evenly. There is a method of maintaining a uniform temperature distribution by attaching a rotary vane to the rear surface of the refrigerating compartment, rotating the rotary vane, adjusting the discharge angle of the cold air, and discharging the cold air to the higher temperature side. The rotary blades are mainly used to determine the direction in which cold air is discharged according to the stop angle position during rotation. The blowing fan discharges the cold air at a constant speed by the rotational force to supply the cold air into the refrigerating chamber.

However, in such a refrigerator, the blowing force due to the rotation of the blowing fan is always fixed, which disadvantageously disables the distribution according to the distance of the region where the cool air is discharged. That is, when it is desired to discharge the cold air to the front portion of the refrigerating compartment far from the blowing fan, it is necessary to rotate the blowing fan at a high speed to increase the discharge speed of the cold air. It is necessary to continuously rotate or stop the blowing fan to weaken the discharge speed of the cool air. However, the conventional blowing fan is unable to control the rotational speed of the blowing fan because the rotational speed is always fixed.

In addition, it is possible to distribute the cold air according to the distance from the blowing fan only by adjusting the rotating speed of the blowing fan. However, since the cold air distribution function according to the angle is not provided and the temperature can not be controlled uniformly, . Therefore, as a precondition for adjusting the discharge speed of the cold air by adjusting the rotational speed of the blower fan and adjusting the direction of the discharge of the cold air by the rotary blades, The temperature of each part of the refrigerating compartment is not accurately measured because only one temperature sensor is used at the upper and lower ends of the refrigerating compartment and two temperature sensors are used in a normal refrigerator.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to accurately deduce the temperature value of each part of the refrigerating compartment with a small number of temperature sensors using a fuzzy model having a reasoning function, The present invention provides a temperature control method and a temperature control device for a refrigerator which can accurately maintain the temperature in the refrigerating compartment without being concentrated on a specific area by correcting the cold air distribution according to the distance and the angle.

1 is a partial front view of a refrigerator;

FIG. 2 is an enlarged perspective view of the rotary blade. FIG.

FIG. 3 is a diagram showing the distribution of cold air according to the distance in the refrigerating compartment according to the rotating speed of the air blowing fan and the stationary angle position of the rotating blades.

FIG. 4 is a graph illustrating the speed at which the blower fan must rotate to achieve cold air distribution over a distance.

Figure 5 is a table illustrating data for applying the TSK fuzzy model.

FIG. 6 is a graph showing each divided structure when the data of Table 1 of FIG.

7 is a schematic perspective view of each stage of the refrigerator compartment showing the selected points for measuring the temperature inside the refrigerator compartment;

FIG. 8 is a control block diagram of a temperature control apparatus according to the present invention; FIG.

FIG. 9 is a circuit diagram of a control device for implementing speed control of a blowing fan and position control of a rotating blade according to the present invention; FIG.

10 is a graph showing a waveform of an AC power supply voltage.

FIG. 11 is a graph showing waveforms in which a zero voltage is detected and output from a zero voltage detecting unit; FIG.

12 is a graph showing a trigger signal generated from a trigger pulse generating unit in the microcomputer at a time delayed by a predetermined section alpha from the waveform of FIG. 11;

FIG. 13 is a graph showing a waveform of a power supply voltage applied to a drive motor as an AC waveform having a predetermined section;

DESCRIPTION OF THE REFERENCE NUMERALS

10: refrigerating chamber 11, 12: temperature sensor

20: Rotating blade 31: Microcomputer

37: rotary blade position sensor 41: drive motor

45: Triac 47: AC power source

49: Transformer 51: Fuzzy inference unit

53: delay time calculating unit 55: trigger pulse generating unit

57: velocity error calculation unit 59: angular position error calculation unit

61:

According to the present invention, the cold air discharge speed according to the cold air discharge direction into the refrigerating chamber and the rotational speed of the air blowing fan is adjusted according to the stationary angle position of the rotary blades, A method of controlling a temperature of a refrigerator that distributes cold air, comprising the steps of: constructing a fuzzy model for inferring a portion having the highest temperature among various portions in a refrigerating chamber; Measuring a temperature change at a predetermined location in the refrigerating chamber; Calculating an optimal equilibrium angular position at which the rotary blade must stop toward an inferred position and an optimal equilibrium velocity at which the blower fan should be rotated by fuzzy inference by the fuzzy model according to the measured value of the temperature change, Wow; Controlling the rotational speed of the blowing fan according to the equilibrium speed and controlling the stopping angle position of the rotating blade according to the equilibrium angular position.

The step of constructing the fuzzy model may include a step of preparing measurement data of a distance from the blowing fan and a temperature change rate at various positions different from each other from the rotary vane in accordance with the temperature change value indicated by the temperature sensor in the refrigerating chamber Wow; Performing fuzzy division based on the measurement data; Selecting an optimal structure among the divided structures of the fuzzy divided area; The temperature in the refrigerating compartment can be accurately inferred by fuzzy inference based on the TSK-fuzzy model by constructing the line type inferring the highest temperature on the basis of the optimal structure.

The step of controlling the rotational speed of the rotary vane may include the steps of generating an AC voltage having an effective value corresponding to a maximum driving speed of the blowing fan; Calculating an equilibrium voltage having an effective value corresponding to the equilibrium velocity; Generating a balanced voltage by cutting a waveform of the AC voltage by a predetermined interval; And supplying the balanced voltage to a driving motor for driving the blowing fan. Thus, a voltage obtained by cutting the maximum voltage supplied to the driving motor is supplied to easily vary the rotational speed of the driving motor .

The step of cutting the AC voltage may include detecting a time point at which the instantaneous value of the waveform of the AC voltage becomes zero; Calculating a delay time from a time point at which the waveform becomes a zero, in which the waveform must be cut to generate the balanced voltage; And a step of cutting the waveform during the delay time from a time point at which the instantaneous value becomes zero so as to detect a zero crossing point of the voltage and determine a quantity to be cut off as a function related to the delay time, Is easy to implement.

In the control by this method, the step of detecting the actual rotational speed of the blowing fan; Calculating a speed error between the actual rotation speed and the equilibrium speed; And correcting the rotational speed of the blowing fan by reflecting the calculated speed error, it is possible to correct the rotational speed of the blowing fan when the actual equilibrium speed is different from the actual rotational speed of the blowing fan, do.

Detecting an actual stop angle position of the rotary vane; Calculating an angular position error between the actual angular position and the angular position; And further correcting the stop angle position of the rotary vane by reflecting the calculated position error, thereby making it possible to perform more accurate control.

According to another aspect of the present invention, there is provided a method for controlling the cooling air discharge speed according to the direction of the cold air discharge into the refrigerating chamber and the rotational speed of the blower fan according to the stationary angle position of the rotating blades, A temperature measuring device for measuring a temperature change at a predetermined location in the refrigerating compartment; A fuzzy inference unit that fuzzy inference is performed according to the measured value of the measurement unit to deduce an equilibrium angular position corresponding to an optimal rotational velocity of the fan and a rotational angle of the rotor, ; A rotation speed controller for controlling the rotation speed of the blowing fan according to the inferred equilibrium speed; And a stationary angle position controller for controlling the stationary angle position of the rotary vane according to the inferred balance angle position.

Here, the rotary blade control unit may include: a balanced voltage operation unit for calculating an equivalent voltage having an effective value corresponding to the equilibrium speed; And a balanced voltage generator for generating a balanced voltage having an effective value corresponding to the equilibrium velocity by cutting the AC voltage for a predetermined interval to supply the generated balanced voltage to the blower fan.

The rated voltage generating unit may include: a zero voltage detecting unit detecting a time point at which the instantaneous value of the waveform of the alternating voltage becomes zero; A delay time calculating unit for calculating a delay time from a time point at which the waveform becomes a zero at which the waveform must be cut to generate the balanced voltage; And a waveform cutting unit for cutting the waveform from a time point at which the instantaneous value becomes zero to a delay time point at which the delay time has elapsed.

The waveform cutting unit may include: a triac connected in series with the power generating unit; And a trigger pulse generator for applying a trigger signal to the gate terminal of the triac at the delay time.

An actual speed detecting section for detecting an actual rotational speed of the blowing fan; and a speed error calculating section for calculating a speed error between the actual rotational speed and the equilibrium speed; It may be more effective that the rotation speed control unit corrects the rotation speed of the blowing fan by reflecting the speed error calculated by the speed error calculation unit.

An actual stop angle position detection unit for detecting an actual stop angle position of the rotary vane; And an angular position error calculator for calculating an angular position error between the actual angular position and the angular position of the balance; And the stop angle position control unit may further correct the stop angle position of the rotary vane by reflecting the position errors calculated by the respective position error calculation units.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 is a partial front view of the refrigerator; As shown in the figure, a refrigerating compartment 10 is formed in a lower area of the refrigerator, and an inner space of the refrigerating compartment 10 is divided along a vertical direction. A so-called vegetable compartment 1 is provided in the bottom portion of the refrigerating compartment 10 to store vegetables, and a so-called fresh compartment 2 is provided in the upper area. The space excluding the vegetable compartment 1 and the fresh compartment 2 is partitioned by the ¾ H 5, the second ½ H 6 and the third ⅓ H 7 at the top along the up and down direction, This name is used in the description of FIG.

Two temperature sensors 11 and 12 are provided in the refrigerating compartment 10 and an S1 sensor 11 is provided on the left side of the refrigerating compartment 5 to measure the temperature of the upper left portion of the refrigerating compartment, Is provided on the right side of the refrigerator compartment to measure the temperature of the lower right portion of the refrigerating compartment. A cold air discharge unit 15 is provided on the inner rear surface of the refrigerating compartment 10 and a rotary blades 20 are installed in the cold air discharge unit 15 so as to be rotatable along the vertical direction so as to adjust the discharging direction of the cold air.

2 is an enlarged perspective view of the rotary vane. The rotary vane 20 includes a rotary vane drive motor (not shown), and the upper vane 21, the middle vane 22, and the lower vane 23 are arranged along the vertical direction. Each wing is arranged corresponding to the height of ¾ H (5), ½ H (6), and ⅓ H (7). The wings 21, 22, and 23 are integrally rotated about the rotary shaft 25 as a center. The directions indicated by the respective wings 21, 22, and 23 are different from each other, and the angle of difference between the wings is 60 degrees apart. In the refrigerating chamber 10, a blowing fan (not shown) and an evaporator (not shown) are provided on the rear surface of the rotary vane 20, and the cold air from the evaporator is blown into the refrigerating chamber by the blowing fan. Cooling air from the evaporator is supplied to each of the chambers 5, 6 and 7 of the refrigerating chamber 10 by the rotation of the blowing fan, and the discharge speed of the discharged cool air is controlled by the rotational speed of the blowing fan.

The rotary vane 20 serves to discharge cold air intensively to a specific region where the temperature is raised by blowing cold air in a state of being stopped in a specific direction, that is, at a still angle position. At this time, since the angles of the rotary blades at the respective stages are different from each other, the discharge directions of the cold air are also different from each other.

FIG. 3 is a diagram showing the cold air distribution in the refrigerating compartment according to the rotating speed of the air blowing fan and the stationary angle position of the rotating blades, and FIG. 4 is a diagram showing a cross section of the refrigerating compartment. And the speed at which it should rotate.

The direction in which air is blown is adjusted to the left side, the center side, and the right side depending on the stationary angle position of the rotary vane 20. It is preferable that the control of the stop angle position is changed continuously while having a continuous value toward the highest temperature in the refrigerating compartment. However, since the cooling air discharging speed by the blowing fan is controlled at the same time, a large number (about 5) of discrete values It is also possible to control by an angle only.

When the rotational speed of the blowing fan is high, the cool air is discharged toward the front portion of the refrigerating chamber (10) at a relatively large distance from the blowing fan. When the rotational speed of the blowing fan is low, Cold air is mainly discharged.

P _R denotes the rear area of the refrigerator compartment close to the rotary vane, P _F denotes the front area of the refrigerator compartment away from the rotary vane, and P _M denotes the middle area thereof. No. When the ventilation fan rotates at a rate of 4 degrees V _L mainly the cool air is distributed to P _R region, when the blower fan rotated at a speed of V _M is mainly cool air is distributed to P _M areas, at a speed of V _H When the blowing fan rotates, the cold air is mainly distributed to the P _F region. The rotational speed of the blowing fan is not controlled to have a discontinuous value but is controlled so as to rotate at a rate at which the cool air reaches a point deduced to be the highest temperature so that actually the continuous value between the minimum rotational speed and the maximum rotational speed As shown in FIG.

In the present invention, the temperature of each part in the refrigerating compartment is inferred and the learning is performed based on the data based on the estimated temperature, so that the cold air is discharged toward the portion determined to be the highest temperature. The implementation of the method is divided into two stages.

The first step is to accurately deduce the temperature of various parts in the refrigerating chamber 10 by using only the two temperature sensors S1 and S2 by fuzzy reasoning. We use fuzzy inference based on the TSK fuzzy model.

The second step is to control the rotational speed of the blowing fan and the stopping angle position of the rotating blades so that the cool air can be discharged at an optimum speed and angle to reach the inferred position. The rotational speed control of the blowing fan is controlled by reducing the rotational speed of the blowing fan by reducing the effective value of the voltage by cutting off the waveform of the voltage applied to the driving motor for driving the blowing fan.

Each step will be described in detail below.

The first step is the inference step by TSK fuzzy (Takagi-Sueno-Kugo fuzzy). To illustrate this step, we first explain the inference process of TSK fuzzy as a general example.

Fuzzy inference requires multiple data for each of a number of variables. Table 1 is illustrated in FIG. 5 to illustrate this data. In Table 1, X1, X2, X3, and X4 are input variables and Y is an output variable. In this example, there are four input variables and one output variable. The numerical relationships shown in Table 1 for the input and output variables are obtained by measurement. It is the ultimate goal of the TSK fuzzy to express the linear relationship between the input and output variables using a formula of these multiple measurement values. Therefore, the ultimate linear form expressing the input / output relations we want to obtain is expressed as the following equation, which is the conclusion of fuzzy reasoning.

As shown in Table 1, the values of the outputs according to the changes of the respective input variables are different according to the degree of contribution of the respective variables to the total output, and the different degrees are the respective input variables (X1, X2, X3, X4) (A ₁ , a ₂ , a ₃ , a ₄ ) that are multiplied by the coefficients A ₁ , A ₂ , a ₃ , and a ₄ . Hereinafter, each stage is divided into stages.

(Stage 1)

First, a line form representing the input / output relationship is constructed using the data given in Table 1. The least squares method used in numerical analysis is generally used, and the least variable is reduced by using the variable reduction method by the error rate. The equation thus obtained is as follows.

This form is like equation (1), but it is not the final equation to be sought but it is the basis for constructing the fuzzy model for fuzzy reasoning. Based on this equation, we divide the region with the largest contribution, and obtain the optimal line form that most appropriately expresses the contribution of each variable. In the equation (2), the variable X4 was removed by an algorithm based on the variable reduction method.

For this equation, we apply the general inconveniences to model the input / output relationship of the nonlinear system as a polynomial of the input variable. In order to obtain the incongruence value, we divide the whole data into two groups and create group A and group B, and substitute them into the following equation.

here, Is an estimate of the output of group A by the fuzzy model obtained according to group A, Is an estimate of the output of group A by the fuzzy model obtained according to group B, Is an estimate of the output of group B by the fuzzy model obtained according to group B, N _A is the number of data in the group A, n _B is the number of data in the group B, and the first term is an estimate of the output of the group B by the fuzzy model obtained according to the group A, The difference between the estimates of the outputs by group B and the second is the difference between the estimates of the outputs by group A and group B for the input data of group B. [

The uncomfortable value thus obtained is called U.C (1). The incongruous value obtained for the data in Table 1 is,

to be.

(Stage 2)

We set up a fuzzy model with two plant laws. Here, the problem of structure setting of the preamble corresponding to the if part of the if-then rule of the fuzzy model comes out. In the structure setting, the selection of the variable and the fuzzy division are considered at the same time.

First, we consider a structure that has only one of X1, X2, X3, and X4 as a preconditioner variable, and divides the space into two. Therefore, there are four possible structures for the premise. For example,

L1: if X1 = SMALL, then Y =

L2: if X1 = BIG, then Y =

Which is the model of the two plant laws. In the second structure,

L1: if X2 = SMALL, then Y =

L2: if X2 = BIG, then Y =

to be.

The preconditioner parameters are set for these preconditioner structures, and the structure and parameters of the conclusion section are set based on the results. The U.C value is calculated as follows.

U.C (2-1) = 5.4

U.C (2-2) = 3.5

U.C (2-3) = 3.3

U. C (2-4) = 4.6

Here, the first number in parentheses denotes fuzzy two-part, and the second number is a number equal to the index of the variable. For example, UC (2-4) means an incongruous value at the time of fuzzy two- (The same shall apply hereinafter)

Comparing these values, the value of U.C (2-3) is the smallest, so we construct the fuzzy model around it. The constructed fuzzy model is as follows.

(Stage 3)

Since the variable X3 is entered in the precondition of stage 2, the fuzzy three-division is performed based on the variable X3. Variables to be added to the fuzzy three-partition are those whose U.C value is small in stage 2. Therefore, here, fuzzy three-division is performed around X2.

The possible structure of the preamble is divided into three areas as shown in Fig.

Taking the third of these as an example,

L1: if X3 = SMALL, then Y =

L2: if X2 = MEDIUM, then Y =

L3: if X2 = BIG, then Y =

As shown in Fig.

When the U.C value is obtained by setting the parameter setting and the conclusion part for the three structures, it can be seen that the first structure has the minimum U.C value as follows.

This is the fuzzy model partition structure of the stage 3.

(Stage 4)

The fuzzy partitioning and the process of finding the incongruity for each partition structure are repeated. This is done until the U.C value reaches the smallest value. If the value is no longer small, take the structure at that time as an optimal structure and obtain the expression of the conclusion.

The conclusion of the conclusion can be regarded as reflecting optimally the contribution of each variable, and the conclusion of the conclusion can be seen as expressing this relation sufficiently.

Hereinafter, a process of creating a line format by obtaining the conclusion of the if-then rule in the present invention will be described in detail.

First, in order to obtain a fuzzy model for estimating the temperature distribution in the hood by using the measured values of the S1 sensor 11 and the S2 sensor 12 in FIG. 1, the interior of the refrigerating chamber 10 is firstly taken to the upper and lower positions, The data on the temperature change at various points are required depending on the distance between the two points.

Figure 7 shows each point selected to measure the temperature inside the refrigerating compartment. The plane of each stage (¾H, ½H, ⅓H) in the refrigerating compartment is indicated by 9 points of 3 × 3. Therefore, the number of points to be measured is 27. These 27 points are named t1 to t27. First, the difference between the temperatures indicated by the two temperature sensors (S1, S2) and the measured values of the temperature change rate at 27 points according to the rate of change are tabulated. The table by this method is similar to Table 1 in Figure 5. The table thus constructed shows the temperature change rate at 27 points with respect to the temperature difference change indicated by the temperature sensors S1 and S2 in order to construct the fuzzy model for the fuzzy inference in the present invention.

Here, the input variable is a measurement value of the temperature of the 27 points (t1 to t27) with respect to the following values of the variables X1, X2, and X3.

X1 = S2 (k) - S1 (k)

X2 = S2 (k-1) - S1 (k-1)

X3 = S2 (k-2) - S1 (k-2)

to be. Here, S1 (k) is a measured value of the current S1 sensor 11, S1 (K-1) is a measured value of the S1 sensor 11 one minute before, S1 (k- ). The same is true of the S2 sensor 12. Therefore, X1 is the difference between the temperature measurement values of the two temperature sensors 11 and 12 at present, X2 is the difference between the temperature measurement values of the two temperature sensors 11 and 12 one minute before, X3 is the temperature difference between the two temperature sensors 11 and 12 Lt; / RTI >

The output variable is the highest temperature among the 27 points (t1 to t27) with respect to the measured values of the variables X1, X2, and X3. Therefore, these data have data on the temperature difference indicated by the measured values of the two temperature sensors S1 and S2 and the trends of the temperature changes of 27 points according to the temporal change of the temperature difference.

The TSK fuzzy theory as described above is applied using these tables. In other words, a fuzzy structure with the smallest U.C value is selected by performing a fuzzy two-part division for each variable and performing a fuzzy division by performing three division based on a variable having the smallest U.C value among them. The parameters of the preliminary part of the selected fuzzy structure are obtained, and the final line form to be obtained is constructed accordingly.

For convenience of explanation, it is assumed that the final fuzzy structure obtained is equal to the following. (The final selected fuzzy structure may vary depending on the experimental data, where the selected structure and the resulting values are not actually tested but are virtually set to represent the form of the final result.)

This equation is based on the assumption that an optimum structure is obtained in the fuzzy quadrant, and Y1 to Y4 are linear form in each region of the quadrant structure. When the output Y is calculated from the above fuzzy model,

g1 = - (| X1 + 6 | - | X1-8 |) / 14

g2 = - (| X1 + 18 | - | X1 - 29 |) / 11

W1 [1] = 0.5 (1 + g1)

W1 [2] = 0.5 (-g1-g2)

W1 [3] = 0.5 (1 + g2)

W2 [1] = 0.5 (1 - | X2 - 2 | - | X2 - 16 |) / 14

W2 [2] = 1-W2 [1]

Y1 = W1 [1] Y1 + W1 [2] W2 [1] Y2 + W1 [2] W2 [

to be. g1 and g2 are the membership functions of the first and second split patterns of the above-described structure, and W represents the degree of contribution of each region to the entire equation according to the general formula of the TSK fuzzy, It is the weight of reasoning. Y is the reasoning equilibrium position at which the cold air should be discharged for optimal temperature equilibrium as the final output, and the equilibrium velocity of the blowing fan and the angular position of the rotary vane to which cold air is to be discharged toward this position, Is calculated by the fuzzy inference unit in the microcomputer on the basis of the graph as shown in Fig.

Hereinafter, as a second step, the step of controlling the blowing fan and the rotating blades at the estimated equilibrium velocity and the equilibrium angular position is performed.

FIG. 8 is a control block diagram of a temperature control apparatus for a refrigerator according to the present invention. The microcomputer 31 performs overall control of the refrigerator. The S1 sensor 11 and the S2 sensor 12 are provided as temperature sensors to detect the temperature in the refrigerating chamber and provide data of the temperature change necessary for the fuzzy inference. The F fan (33) and the R fan (34) are the blowing fan for the refrigerating compartment and the blowing fan for the refrigerating compartment, respectively. The microcomputer 31 controls the blowing fans and the compressor 32 to control the operation of the entire refrigerator.

The rotary fan position sensor 37 detects the non-rotation angle position of the actual rotary blade in accordance with the change of the position of the rotary blades 20 and provides data for controlling the accurate stop angle position. And provides the data for detecting the rotational speed of the actual blowing fan in accordance with the change of the position of the fan so as to control the rotational speed accurately. The zero voltage detecting circuit 38 will be described later.

FIG. 9 is a circuit diagram of a temperature control apparatus for a refrigerator for realizing speed control of a blowing fan and position control of a rotating blade according to the present invention, and FIG. 10 is a graph showing waveforms of an AC voltage. As shown in these figures, the present temperature control device includes a driving motor 41 for a blowing fan, an AC power source 47 for generating an AC power source voltage applied to the driving motor 41, an AC power source 47, A transformer 49 for converting the voltage from the microcomputer 31 into a recognizable small signal of the microcomputer 31, and a waveform mover.

The AC power supply 47 supplies power necessary for rotating the drive motor 41. [ The voltage supplied by the AC power source 47 has a sinusoidal waveform as shown in FIG. 10 as a voltage for generating the maximum rotational speed in rotating the drive motor 41, And adjusts the effective value of the voltage actually applied to the driving motor 41 to adjust the rotational speed of the blowing fan. The process is as follows.

The voltage from the AC power source 47 is converted into a pulse voltage that can be recognized by the microcomputer 31 by the transformer 49, the bridge circuit 46 and the transistor 48 performing the switching operation. That is, the output voltage of the transformer 49 is full-wave rectified by the bridge circuit 46 and applied to the microcomputer 31 via the transistor 48 which performs the switching operation. The trigger pulse generator 55 in the microcomputer 31 detects the time point at which the zero voltage becomes the waveform of this full wave rectified voltage.

The fuzzy inference unit 51 in the microcomputer 31 rotates the blowing fan for the temperature equilibrium in the refrigerating compartment according to the above-mentioned final formula in which the fuzzy inference is performed according to the temperature measurement values from the respective temperature sensors 11 and 12, And outputs the highest temperature position in the refrigerating compartment for stopping. Then, the balancing voltage calculating unit 52 calculates the effective value of the voltage to be applied to the driving motor 41 for outputting the equilibrium velocity of the blowing fan estimated by the fuzzy inference unit 51.

The process of cutting the waveform of FIG. 10 for a predetermined interval in order to generate the voltage having the calculated effective value is performed in the waveform cut-out portion. The corrugated portion is composed of a light triac 43 and a triac 45. The triac 45 is connected in series with the AC power supply 47 and the drive motor 41 and receives the output from the optical triac 43 as a gate signal. The light triac 43 generates a gate signal to the triac 45 by a trigger signal from the trigger pulse generator 55 in the microcomputer 31. [

The delay time calculating unit 53 in the microcomputer 31 determines a section to cut out the waveform from the detected zero voltage point and the trigger pulse generating unit 55 in the microcomputer 31 sets the optical triac 43).

12 is a graph showing a trigger signal generated from a trigger pulse generating unit in the microcomputer at a time delayed by a predetermined section alpha from the waveform of FIG. 11; FIG. 11 is a graph showing a waveform for detecting and outputting zero voltage at the zero voltage detecting unit; And FIG. 13 is a graph showing a waveform of a power supply voltage applied to the drive motor as an AC waveform having a predetermined section cut off. As shown in these figures, the AC voltage applied to the triac 45 is cut off for a time delayed from the zero voltage by the? Section as shown in FIG. 13, so that the effective value of the voltage supplied to the drive motor 41 is also small And the rotation speed of the drive motor 41 is reduced.

The cutting interval? Becomes larger when the inferred equilibrium velocity is relatively low in the fuzzy inference unit 51 in the microcomputer 31. If the equilibrium velocity is large, the cutoff interval? Is increased. In this way, the rotational speed of the blowing fan is adjusted.

The rotary blade 20 is driven by a separate rotary blade driving motor for driving the rotary blades and each position error calculation section 59 in the microcomputer 31 is provided with rotary blades 20 for detecting the actual non- The actual position of the stationary angle detected by the position sensor 37 is compared with the position of the estimated balance angle from the fuzzy inference unit 51 to calculate each position error of the rotating blades. The stop angle position control unit 61 in the microcomputer 31 then corrects the stop angle position of the rotary vane 20 by reflecting the position errors calculated by the position error calculation unit 59.

On the other hand, the R fan speed sensor 39 outputs the angular position of the blowing fan at every time when the actual blowing fan rotates, and transmits it to the microcomputer 31. The speed error calculator 57 in the microcomputer 31 compares the actual rotational speed of the blower fan sensed by the R fan speed sensor 39 with the equilibrium speed estimated by the fuzzy inference unit 51 in the microcomputer 31 Thereby calculating the velocity error of the blowing fan.

Then, the delay time calculating section 53 calculates the delay time by reflecting the speed error of the blowing fan calculated by the speed error calculating section 57, and the trigger pulse generating section 55 calculates the delay time at which the speed error is reflected And outputs the trigger signal to the optical triac 43 based on the rotational speed of the blowing fan. That is, when the actual speed of the blower fan sensed by the R fan speed sensor 39 is faster than the equilibrium speed estimated by the fuzzy inference unit 51, the effective value of the power supply voltage is made smaller by further increasing? If the actual rotational speed is slower than the equilibrium speed, the actual rotational speed is made larger by decreasing? To further increase the effective value of the power supply voltage. This feedback process results in more accurate control at the equilibrium velocity.

As described above, according to the present invention, the temperature value of each part of the refrigerating compartment can be accurately inferred using only a small number of temperature sensors using the fuzzy model, and the rotation speed of the blowing fan and the stopping angle position of the rotating blades A temperature control method for a refrigerator and a temperature control device for a refrigerator in which a temperature in a refrigerating compartment can be maintained uniformly without being concentrated on a specific area by performing cold air distribution according to distance and direction.

Claims (12)

A method for controlling the temperature of a refrigerator for controlling the cold air discharge speed according to the cold air discharge direction into the refrigerating chamber and the rotating speed of the blower fan according to the stationary angle position of the rotary blades and performing cold air distribution according to the position of the rotary blades Comprising the steps of: constructing a fuzzy model for inferring the highest temperature among the various parts of the refrigerating compartment; Measuring a temperature change at a predetermined location in the refrigerating chamber; Calculating an optimal equilibrium angular position at which the rotary blade must stop toward an inferred position and an optimal equilibrium velocity at which the blower fan should be rotated by fuzzy inference by the fuzzy model according to the measured value of the temperature change, Wow; Controlling the rotating speed of the blowing fan according to the equilibrium speed and controlling the stopping angle position of the rotating blades according to the equilibrium angular position. 2. The method according to claim 1, wherein the step of constructing the fuzzy model comprises the steps of: measuring the distance from the blowing fan to the temperature change value indicated by the temperature sensor in the refrigerating chamber and the measured value data ; Performing fuzzy division based on the measurement data; Selecting an optimal structure among the divided structures of the fuzzy divided area; And calculating a line form deducing the highest temperature portion on the basis of the optimal structure. The method according to claim 1 or 2, wherein the step of controlling the rotational speed of the blowing fan includes the steps of: generating an AC voltage having an effective value corresponding to a maximum driving speed of the blowing fan; Calculating an equilibrium voltage having an effective value corresponding to the equilibrium velocity; Generating a balanced voltage by cutting a waveform of the AC voltage by a predetermined interval; And supplying the balanced voltage to a driving motor for driving the blowing fan. 4. The method of claim 3, wherein cutting the AC voltage comprises: detecting a time point at which the instantaneous value of the waveform of the AC voltage becomes zero; Calculating a delay time from a time point at which the waveform becomes a zero, in which the waveform must be cut to generate the balanced voltage; And cutting the waveform for the delay time from a time point at which the instantaneous value becomes zero. The method as claimed in claim 1 or 2, further comprising: detecting an actual rotational speed of the blowing fan; Calculating a speed error between the actual rotation speed and the equilibrium speed; And correcting the rotational speed of the blowing fan based on the calculated speed error. 3. The method of claim 1 or 2, further comprising the steps of: detecting an actual stop angle position of the rotary vane; Calculating an angular position error between the actual angular position and the angular position; And correcting the stop angle position of the rotary vane by reflecting the calculated position errors. A temperature control device of a refrigerator for controlling a cold air discharge speed according to a cold air discharge direction into a refrigerating chamber and a rotational speed of a blowing fan according to a stationary angle position of a rotary blade and performing cold air distribution according to a stop angle position of the rotary blades and a distance from the blowing fan A measuring unit for measuring a temperature change at a predetermined location in the refrigerating compartment; A fuzzy inference unit that fuzzy inference is performed according to the measured value of the measurement unit to deduce an equilibrium angular position corresponding to an optimal rotational velocity of the fan and a rotational angle of the rotor, ; A rotation speed controller for controlling the rotation speed of the blowing fan according to the inferred equilibrium speed; And a stationary angle position controller for controlling the stationary angle position of the rotary vane according to the inferred equilibrium angular position. The apparatus of claim 7, wherein the rotation speed control unit comprises: a balanced voltage operation unit for calculating a balanced voltage having an effective value corresponding to the balanced speed; And a balanced voltage generating unit for generating a balanced voltage having an effective value corresponding to the equilibrium velocity by cutting the AC voltage for a predetermined interval to supply the generated balanced voltage to the blowing fan. The apparatus of claim 8, wherein the balanced voltage generating unit comprises: a zero voltage detecting unit detecting a time point at which the instantaneous value of the waveform of the AC voltage becomes zero; A delay time calculating unit for calculating a delay time from a time point at which the waveform becomes a zero at which the waveform must be cut to generate the balanced voltage; And a waveform cut-out unit for cutting the waveform from a time point at which the instantaneous value becomes zero to a delay time point at which the delay time elapses. The apparatus of claim 9, wherein the waveform cutout portion comprises: a triac connected to the power generating portion in series; And a trigger pulse generator for applying a trigger signal to the gate terminal of the triac at the delay time point. 11. The air conditioner according to any one of claims 7 to 10, further comprising: an actual speed detecting unit for detecting an actual rotating speed of the blowing fan; Further comprising a velocity error calculator for calculating a velocity error between the actual rotation speed and the equilibrium velocity; Wherein the rotation speed control unit corrects the rotation speed of the blowing fan by reflecting the speed error calculated by the speed error calculation unit. 11. The apparatus according to any one of claims 7 to 10, further comprising: an actual stop angle position detection unit for detecting an actual stop angle position of the rotary vane; And an angular position error calculator for calculating an angular position error between the actual angular position and the angular position of the balance; Wherein the stop angle position control unit corrects the stop angle position of the rotary vane by reflecting the position errors calculated by the respective position error calculation units.