JPH07217996A - Fan control method of electric heat storage heater - Google Patents

Abstract

PURPOSE:To provide a fan control method of an electric heat storage heater wherein fan noise is reduced and predetermined heating capability is ensured irrespective of a change in the amount of heat storage in a heat storage structure to keep smaller a difference between heating temperature and set temperature. CONSTITUTION:A temperature controller 20 of an electric heat storage heater controls an fan 10 continuously to optimum revolutions using fuzzy operation in response to a difference between detection temperature by a room temperature sensor 14 and set temperature of room temperature set means 16 to keep smaller the difference between the detection temperature and the set temperature. The air fan 10 is rotated at a low speed where room temperature can be kept unchanged to eliminate wasteful fan rotation and for reduction of fan noise, and predetermined heating capability is ensured with an increase of the revolutions of the fan when temperature of the heat storage structure is lowered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention aims to reduce fan noise and at the same time keep a small difference from the set temperature by obtaining a constant heating capacity regardless of the change in the amount of heat stored in the heat storage body. The present invention relates to a fan control method for an electric heat storage heater.

[0002]

2. Description of the Related Art There is an electric heat storage heater as an energy-saving type electric heater that uses late-night power, snow melting power, and the like.

The electric heat storage heater has a heat storage body for heating, stores heat in the heat storage body by using late-night power, power for snow melting, etc., and uses the stored heat to perform heating during power shortage during the daytime. By doing so, the excess power is efficiently used.

As such an electric heat storage heater, for example,
There is a fan type electric heat storage heater shown in FIG.

This electric heat storage heater has a heat storage portion 1 provided above the heater body and a blower portion 2 provided below the heat storage portion 1.
The heat storage unit 1 includes a heat storage body 6, a heat insulating material 4 surrounding the heat storage body 6, and a heater 5 for heating the heat storage body 6.
It consists of

The heat storage body 6 is formed by stacking five heat storage bricks arranged in a row in two stages to form a set, and the set of bricks is stacked in three stages, and the heater is arranged for each stage of the bricks stacked in three stages. 5 is attached.

The heater 5 is inserted through the heat storage brick, and therefore, the brick is heated directly from the inside so that heat can be transferred to the brick without leakage.

The heater 5 is driven by late-night power, snow-melting power, or the like, and heats the heat storage body 6 with low-cost power.

The heat insulating material 4 is composed of a heat insulating ceramic fiber and a microtherm which are attached to the inner walls of the heater body, which face the front and rear surfaces, the side surfaces, and the upper surface of the heater except the lower portion of the heat storing body 6, at a distance from the heat storing body 6. And a heat insulating ceramic plate 17 attached to the lower surface of the heat storage body 6, and between the heat insulating material 4 and the heat storage body 6, the heat stored in the heat storage body 6 indicated by the arrow in FIG. An air passage 7 for taking out air is formed.

The blower unit 2 is provided with a blow-out port 8, a suction port 9 and a blower fan 1 provided to face the front and rear surfaces of the heater body.
The blower fan 10 is arranged below the heat storage body 6 via the output adjusting damper 11.

Further, between the blower fan (hereinafter referred to as fan) 10 and the outlet 8, a barrier 12 for restricting the blown air of the fan 10 to the outlet 8 is provided, and the cool air sucked from the inlet 9 is , The direction is changed by the barrier 12,
After being blown up through the air passage 7 of the heat storage unit 1 and being heated around the heat storage body 6, the heat is discharged from the outlet 8.

The outlet 8 is provided with an auxiliary heater 13. The auxiliary heater 13 is driven by normal electric power, operates when the temperature of the heat storage body 6 is lowered and the warm air cannot be heated to a prescribed temperature, and heats the warm air.

As described above, the electric heat storage heater controls the room temperature by adjusting the amount of heat discharged from the heat storage body 6 by adjusting the amount of air blown by the fan 10.

Conventionally, such temperature control is performed by a room temperature sensor 14 and a temperature controller 15 provided in the heater main body, as shown in FIG.

That is, the temperature controller 15 turns the fan 10 ON / O according to the deviation between the room temperature detected by the room temperature sensor 14 and the room temperature set by the room temperature setting means 16.
FF control.

For example, as shown in FIG. 8, if the room temperature is lower than the set value by 1 ° C. or more, the fan 10 is operated to blow air to warm the room, and conversely, the room temperature is 1 ° C. lower than the set value.
When the temperature becomes higher than the above, the fan 10 is stopped and the blowing is stopped.
At that time, in the example of FIG. 8, if the temperature is lower than the set temperature by 2 ° C. or more, the rotation speed of the fan 10 is switched to a high speed to shorten the start-up time and shorten the settling time to the set value. It is highly responsive.

[0017]

However, in the above ON / OFF control, which is a non-linear control system, the rotation of the fan is turned ON / OFF at ± 1 ° C. in order to stabilize the control system. Hunting will occur between inside and outside the allowable value of ± 1 ° C. Therefore, there is a problem that the set temperature fluctuates more than the allowable temperature.

Further, in this case, since the room temperature is maintained within the allowable temperature difference, the number of rotations of the fan is constantly increased and the noise due to the wind noise becomes large (at least 42 dB).

Further, in the above electric heat storage heater, as the temperature of the heat storage body decreases during the heat radiation period, the efficiency of heat radiation to the outside air of the heat storage body decreases, and the heating capacity decreases, so that at a constant fan speed. In that case, there is a problem that the room cannot be set to the set temperature and the room temperature is kept low.

Therefore, an object of the present invention is to reduce the deviation from the set temperature, reduce the wind noise, and maintain the room temperature at the set temperature regardless of the decrease in the temperature of the heat storage body.

[0021]

In order to solve the above-mentioned problems, according to the present invention, a heat storage body heated by an electric power in an inexpensive time zone such as a midnight power supply or a snow melting power supply and a blown air around the heat storage body. It has a blower fan that warms the room with the warm air generated by performing the air-conditioning and a room temperature sensor that detects the room temperature.The rotation speed of the blower fan is controlled according to the difference between the temperature detected by the room temperature sensor and the set temperature of room temperature. In such a conventional electric heat storage heater, a method of continuously controlling the number of rotations of the fan according to the temperature difference was performed.

At this time, a method of controlling the rotation speed of the fan by fuzzy calculation based on the detected temperature of the room temperature sensor and the set temperature of room temperature may be used.

Further, a method of controlling the blower fan by pulse width drive control may be adopted.

At this time, if the difference between the temperature detected by the room temperature detection sensor and the set temperature of room temperature is 2 ° C. or more,
A control method may be performed in which the rotation speed of the fan is controlled to the maximum rotation speed and the rotation speed is maintained until the room temperature reaches the set temperature.

[0025]

In such a fan control method for an electric heat storage heater, since the room temperature, which is a control variable, is matched with the set value of room temperature, the fan rotation speed that is an operation variable and that adjusts the heat radiation amount of the heat storage body is adjusted. The additional value control is performed so that the difference between the room temperature sensor and the set value, which is the deviation, becomes zero. At this time, the number of rotations of the fan is continuously changed and controlled according to a temperature difference, for example, according to a determination content (calculation) based on a control expression (description function) that makes the temperature difference proportional to the temperature difference. Therefore, the rotation speed of the fan can be controlled to an appropriate value.

At this time, in the method of controlling the rotation speed of the fan by the fuzzy calculation based on the detected temperature of the room temperature sensor and the set temperature of the room temperature, the determination by the control formula is performed by the fuzzy calculation, for example, An ambiguous conditional expression such as "Increase the rotation speed if the room temperature is low" without converting the disturbance such as the change of the heat capacity in the room, which is a control target that changes every moment and is difficult to quantify, into an accurate control expression. It is possible to control the fan speed accurately to an optimum value by inferring from the above.

Further, in the method of controlling the blower fan by the pulse width drive control, the D / A by the pulse width drive is used.
By the conversion, the above control can be performed by digital control.

When the detection temperature of the room temperature detection sensor is lower than the set temperature of room temperature by 2 ° C. or more, when the method for controlling the rotation speed of the fan to the maximum rotation speed is performed, the control is performed such that the detection temperature is lower than the set temperature. If the temperature is lower than 2 ° C, by saturating the manipulated variable and maintaining the maximum fan speed,
The room temperature can be rapidly raised, the rise time can be shortened, and the settling time to the set value can be shortened to improve the quick response.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a temperature control system according to the fan control method for an electric heat storage heater of the present invention.

This temperature control system comprises a room temperature sensor 14, a room temperature setting means 16 and a temperature controller 20.

The room temperature sensor 14 is a temperature-electricity conversion transducer using a thermistor or the like, for example, and is attached to the heater main body to detect the room temperature.

The room temperature setting means 16 is composed of a temperature setting switch and a display device, and the temperature setting switch and the display device are directly connected to the I / O device of the temperature controller 20 to display the indicated temperature displayed on the display device. The data is input to the temperature controller 20 by selecting it with the temperature setting switch.

The temperature controller 20 comprises an arithmetic unit 21 and a pulse width (PWM) drive generator 22.

The calculation unit 21 has a microcomputer, and the microcomputer has the room temperature sensor 14
And an input I / O device connected to the room temperature setting means 16.

The microcomputer is also connected to the pulse width drive generator 22 via the output port.

As shown in FIG. 2, the pulse width drive generator 22 comprises a switch means 23 such as a thyristor switch provided between the power source and the fan 10 and a drive circuit for driving the switch means 23. Switch means 23 through the drive circuit
By changing the ON and OFF times and changing the duty ratio, the D / A conversion of the operation output is performed.

Therefore, the microcomputer digitally controls the rotation speed of the fan 10 by a built-in control program so that the temperature difference between the detected temperature of the room temperature sensor 14 and the set temperature of the room temperature becomes zero.

A fuzzy arithmetic control program is used as the control program.

The fuzzy operation uses a triangular membership function as shown in FIG. 3, for example, from an ambiguous conditional statement such as "If the room temperature is low, increase the rotation speed of the blower fan 10." Then, the degree of room temperature T ₁ detected by the room temperature sensor is calculated to be “low”. Similarly, when the room temperature is very low, the room temperature T ₁ is “extremely high.” The degree of rotation of the fan 10 is inferred based on the center of gravity obtained from those values.

Therefore, a disturbance such as a change in heat capacity in a room, which is a control target that is difficult to quantify and changes every moment, is not converted into an accurate control expression, and “If the room temperature is low, the rotation speed is increased. From the ambiguous conditional expression such as "," the number of rotations of the fan 10 required to make the temperature difference between the detected temperature of the room temperature sensor 14 and the set temperature of the room temperature zero can be read quickly and accurately, and it is optimal without excessive waste. The fan 10 can be driven by continuously outputting various rotation speeds.

Further, the control by the fuzzy calculation is usually performed when the detected temperature is (set temperature-2 ° C.) or more, and at this time, the detected temperature of the room temperature detecting sensor 14 is 2 ° C. higher than the set temperature of room temperature. If it is lower than the above, the rotation speed of the fan 10 is controlled to the maximum rotation speed, the rotation speed is maintained until the room temperature reaches the set temperature, and the room temperature is rapidly raised to the set temperature. At the beginning, it is full power, and otherwise, it controls to the required heating capacity.

This embodiment is constituted as described above, and the operation of the fan will be described below with reference to the flow chart shown in FIG.

At the same time when the control is started, the temperature controller 20 sets the flag F to 0 (process 100 "the process is omitted hereinafter"). This flag F is for knowing whether the duty ratio is controlled to 100%.

Next, the controller 20 sets the set temperature T ₂
Is read from the room temperature setting means 16, and at the same time, the room temperature data T ₁ is read from the room temperature sensor 14 (101). Then, the difference ΔT (102) between the set temperature T ₂ and the detected temperature T ₁ is obtained from the read data. At this time, if the flag F is 0 (103), the difference from the set temperature T ₂ is −2.
° C. Compares within a either (104), - 2 if within a ° C., the current and the previous detection temperatures T ₁ 'detected temperatures T ₁
The rate of change dT of the detected room temperature is obtained from the above (105). Next, from ΔT and dT, the optimum fan 1 required for heating 1
In order to calculate the number of revolutions of 0 by fuzzy calculation and set the number of revolutions accordingly, for example, the variation ΔD of the duty ratio D of pulse width control (PWM) is calculated (10
6). Then, the change amount ΔD and the previous duty ratio D
And the duty ratio D of this time is determined (107), the switch means 23 is operated with the duty ratio D (108), and the fan 10 is driven (10).
9).

At this time, the difference from the set temperature T ₂ is -2.
When the temperature is higher than 104 ° C. (104), the flag F is set to 1 and the duty ratio D is set to 100% (110), the pulse width (PWM) is output (108), and the fan 10 is driven (109).

On the other hand, when the flag F is 1 (103) and the difference from the set temperature T ₂ is larger than -1 ° C (111),
As in the above process, the flag F is set to 1 and the duty ratio D
Is set to 100% (110), the pulse width (PWM) is output (108), and the fan 10 is driven (10).
9).

If the difference is less than -1 ° C, (1
11), the flag F is set to 0 (112), the optimum rotation speed of the fan 10 required for heating is calculated by fuzzy calculation from ΔT and dT, and the duty by the pulse width (PWM) corresponding to the calculated rotation speed is calculated. A change ΔD of the ratio D is calculated (106). Then, the duty ratio D is determined (107), the switch means 23 is operated with the duty ratio D (108), and the fan 10 is driven (10).
9).

As described above, according to this control method, the rotation speed of the fan 10 is continuously controlled so as to always reduce the temperature difference based on the temperature difference between the detected temperature T ₁ and the set temperature T _2. The temperature difference can be kept small without the hunting operation of 10.

Further, at this time, the rotation speed of the fan 10 is controlled to the minimum necessary rotation speed for maintaining the room temperature at the set value, so that the noise due to the wind noise of the fan 10 can be suppressed to a low level.

Further, even when the temperature of the heat storage body 6 is lowered in the latter stage of heat radiation, the rotation speed of the fan 10 is increased so as to maintain the room temperature at the set value, so that the heating capacity required regardless of the temperature of the heat storage body 6 Can be obtained.

Further, since the rotation speed of the fan 10 is maintained at the maximum rotation speed when the measured room temperature is lower than the set temperature by 2 ° C. or more, it is possible to prevent deterioration of the room temperature rising characteristic such as at the start of heating.

Next, FIG. 5 shows a comparison of the room temperature control characteristics of the electric heat storage heater when the above control flow is used and when the conventional control method is used.

As a result, the allowable error for the set room temperature is
In the conventional example, the temperature is ± 1 ° C., whereas in the example, it is suppressed to approximately ± 0.5 ° C.

Further, after reaching the set room temperature, the rotation speed of the fan 10 is suppressed to a low rotation speed commensurate with maintaining the set room temperature as compared with the conventional one, which causes noise in the conventional case. , 42 dB, while in the present embodiment, it was suppressed to a low level of about 36 dB.

Even when the temperature of the heat storage body 6 in the latter stage of heat radiation is low,
In the conventional example, the heating capacity is lowered and the room temperature cannot be maintained, whereas in the example, the set temperature can be maintained by increasing the rotation speed of the fan 10.

Further, the rise characteristics at room temperature were almost the same as those of the conventional ones, since the rotation speed was maintained at the highest speed.

[0058]

According to the present invention, the number of rotations of the blower fan is continuously controlled so as to reduce the temperature difference between the detected temperature of the room temperature sensor and the set temperature by the above method, so that the temperature difference from the set temperature is reduced. You can hold it down.

Further, at that time, in the case where the control is performed by the fuzzy calculation, the rotation speed of the fan is set to the optimum rotation speed for heating by the temperature detected by the room temperature sensor and the temperature of the set temperature. Precise temperature control is possible.

At this time, the rotation speed of the fan is controlled to the minimum necessary rotation speed for maintaining the room temperature at the set value, so that the noise due to the wind noise of the fan can be suppressed to a low level.

Further, in the latter stage of heat radiation, when the temperature of the heat storage body decreases, the rotation speed is increased so as to maintain the room temperature at the set value, so that the required heating capacity can be obtained regardless of the temperature of the heat storage body. You can

In the case of performing pulse width control, the pulse width output just performs D / A conversion, so that digital control can be performed.

If the rotation speed of the blower fan is maintained at the maximum rotation speed when the measured room temperature is lower than the set temperature by 2 ° C., it is possible to prevent deterioration of room temperature rising characteristics such as at the start of heating.

[Brief description of drawings]

FIG. 1 is a block diagram showing a temperature controller of an embodiment.

FIG. 2 is an explanatory view of the operation of pulse width control according to the embodiment.

FIG. 3 is an explanatory diagram of the operation of the fuzzy operation according to the embodiment.

FIG. 4 is a flowchart showing the operation of the embodiment.

FIG. 5 is a room temperature control characteristic diagram of an example and a conventional example.

FIG. 6 is a partial sectional perspective view of an electric heat storage heater.

FIG. 7 is a block diagram showing a conventional temperature controller.

FIG. 8 is a temperature control characteristic diagram of a conventional temperature controller.

[Explanation of symbols]

 6 Heat Storage Body 10 Blower Fan 14 Room Temperature Sensor 15 Temperature Controller 16 Room Temperature Setting Means 17 Insulating Ceramic Plate 20 Temperature Controller 21 Computing Unit 22 Pulse Width Drive Generator 23 Switch Means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuji Ito 1-3-1, Shimaya, Konohana-ku, Osaka City Sumitomo Electric Industries, Ltd. Osaka Works (72) Inventor Kohei Furukawa 1-1-1, Shimaya, Konohana-ku, Osaka City No. 3 Sumitomo Electric Industries Co., Ltd. Osaka Works (72) Inventor Mori Inaba, Miyoshigaoka, Toyohira-ku, Sapporo-shi, Hokkaido 4-92-1 Mikkaoka Hokkaido Electric Power Co., Inc. Research Institute (72) Inventor Satoru Takeyama Toyohira, Sapporo, Hokkaido Bijogaoka 4-9-2-1, Hokkaido Electric Power Co., Inc. Research Institute (72) Inventor Fujio Sonoda 776 Naie, Naie-cho, Sorachi-gun, Hokkaido Hokkaido Electric Co., Ltd.

Claims (4)

[Claims] 1. A heat storage body heated by electric power in an inexpensive time zone such as midnight power or snow melting power, a blower fan for warming the room with warm air generated by blowing air around the heat storage body, and a room A fan control method for an electric heat storage heater having a room temperature sensor for detecting a temperature, the method controlling a rotation speed of a blower fan according to a difference between a detection temperature of the room temperature sensor and a set temperature of the room temperature, comprising: A fan control method for an electric heat storage heater in which the number of revolutions is continuously controlled according to the temperature difference. 2. The fan control method for an electric heat storage heater according to claim 1, wherein the number of revolutions of the fan is controlled by fuzzy calculation based on the detected temperature of the room temperature sensor and the set temperature of the room temperature. 3. The fan control method for an electric heat storage heater according to claim 1, wherein the blower fan is controlled by pulse width drive control. 4. When the difference between the detection temperature of the room temperature detection sensor and the set temperature of the room temperature is 2 ° C. or more, the rotation speed of the fan is controlled to the maximum rotation speed and the rotation speed is set to the room temperature. 2. Maintaining until reaching
4. A fan control method for an electric heat storage heater according to any one of 3 to 3.