JP2002005529A - Heat storage control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat storage control device capable of preventing over heating of a heat storage material. SOLUTION: The heat storage control device 11 comprises heaters 15a-15f for heating the heat storage material 13; thermocouples 31a and 31b for detecting the temperature of the heat storage material 13; a heat transfer pipe 14 for effecting heat exchange between water flowing to an internal part and the heat storage material 13; and a control device for controlling energization to the heaters 15a-15f, based on the temperature of the heat storage material 13. The thermocouples 31a and 31b are embedded in the vicinity of the center of the heat storage material 13 and in the vicinity of the steam outlet side of the heat transfer pipe 14. When the temperature of the part, where a heat remaining amount is comparatively high, of the heat storage material 13, namely, the heat storage material 13 in the vicinity of the steam outlet of the heat transfer pipe 14, reaches a heat storage upper limit temperature of 550 deg.C, energization to the heaters 15a-15f is respectively cut off. Thereby, over heating of the heat storage material 13 is prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat storage control device that stores heat in a substance having a large specific heat and uses the sensible heat later.

[0002]

2. Description of the Related Art The following is known as this type of heat storage control device. That is, the heat storage material in the case is heated by a heater, and in this state, water is supplied from one of the heat transfer tubes embedded in the heat storage material, and is taken out as steam from the other. The heater is ON / OFF controlled based on temperature information from a temperature sensor arranged near the center of the heat storage material.

[0003]

However, in the conventional heat storage control device, water before heating always flows to the water inlet side of the heat transfer tube, and steam always flows to the steam outlet side of the heat transfer tube. Therefore, the heat storage material near the water inlet side of the heat transfer tube loses heat faster than the heat storage material near the steam outlet side. Therefore,
Even if the temperature near the center of the heat storage material drops to a predetermined temperature, the temperature of the heat storage material near the steam outlet side of the heat transfer tube often does not drop so much. In this state, for example, when the reheating operation is performed, the temperature of the heat storage material near the water inlet side of the heat transfer tube does not easily rise, whereas the temperature of the heat storage material near the steam outlet side increases rapidly. As a result, the temperature difference between the heat storage material near the water inlet side of the heat transfer tube and the heat storage material near the steam outlet side of the heat transfer tube increased, which was inefficient. Moreover, the heat storage material, especially the heat storage material near the steam outlet side of the heat transfer tube is overheated, and there is a possibility that thermal decomposition may start.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a heat storage control device capable of preventing a heat storage material from being overheated.

[0005]

According to the present invention, a heating means for heating a heat storage material filled in a case;
A temperature detecting means for detecting a temperature of the heat storage material, a heat transfer tube disposed in the case and through which a heat medium flows to perform heat exchange between the heat medium and the heat storage material; Control means for controlling energization to the heating means based on the temperature of the heat storage material detected by the detection means, wherein the temperature detection means, at least near the heat medium outlet side of the heat transfer tube The point is that it is arranged in the heat storage material.

According to a second aspect of the present invention, there is provided a heating means for heating a heat storage material filled in a case, a temperature detection means for detecting a temperature of the heat storage material, and disposed inside the case and inside the case. A heat transfer tube through which a heat medium flows and performs heat exchange between the heat medium and the heat storage material, and control for controlling energization to the heating means based on the temperature of the heat storage material detected by the temperature detection means. In the heat storage control device provided with the means, the inside of the case is divided into a plurality of parts, the heating means is arranged for each of the divided sections, and the temperature detecting means is provided so as to correspond to each of the heating means. The gist of the present invention is to individually control the energization of each heating means.

According to a third aspect of the present invention, in the first aspect, the temperature detecting means is provided near the center of the heat storage material. According to a fourth aspect of the present invention, in the first aspect of the present invention, the temperature detecting means is arranged above the center of the heat storage material. And

According to a fifth aspect of the present invention, in any one of the first, third and fourth aspects of the invention, the control means controls the energization of the heating means and the interruption of the energization. The point is that the control is performed collectively. (Function) In the first aspect of the invention, energization of the heating means is controlled based on at least the temperature of the heat storage material near the heat medium outlet side of the heat transfer tube. The heat storage material near the heat transfer medium inlet side of the heat transfer tube loses heat faster than the heat storage material near the heat transfer medium outlet of the heat transfer tube. For this reason, ON / OFF control of the heating means is performed based on the temperature of the portion of the heat storage material having a relatively large amount of residual heat.

According to the invention described in claim 2, based on the heat storage material temperature detected for each of the divided sections in the case,
Each heating means is individually controlled to be energized. For this reason, it is possible to interrupt the energization only for the heating means corresponding to the heat storage material that has reached the set heat storage temperature, or to continue the energization only for the heating means corresponding to the heat storage material that has not reached the set heat storage temperature.

According to the third aspect of the present invention, in addition to the operation of the first aspect, energization of the heating means is controlled based on the temperature of the heat storage material near the center of the heat storage material. That is, when the temperature near the center of the heat storage material falls below the set heat storage temperature, energization to the heating means is started, but when the temperature of the heat storage material near the heat medium outlet side of the heat transfer tube reaches the set heat storage upper limit temperature, the heating means is turned on. Is turned off.

According to a fourth aspect of the present invention, in addition to the operation of the first aspect of the present invention, based on the temperature of the heat storage material above the center of the heat storage material. The heating means is energized. Generally, heat goes up and up. For this reason, the heating means is ON / OFF controlled based on the temperature of the portion of the heat storage material where the residual heat amount is larger.

According to the fifth aspect of the present invention, in addition to the operation of any one of the first, third, and fourth aspects, energization and cutoff of the heating means are collectively performed. Controlled. Therefore, the control is simplified, unlike the case where the heating means is individually controlled.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which the present invention is embodied in a heat storage control device will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, a case 12 constituting the heat storage control device 11 is filled with a heat storage material 13 containing magnesia and nitrate as main components. In the case 12, a heat transfer tube 14 through which water as a heat medium flows, a plurality of heaters 15a to 15f as heating means for heating the heat storage material 13, and each of the heaters 15a to 15f
, A plurality of thermocouples 16a to 16f as temperature detecting means arranged close to each other.

The heat transfer tubes 14 are formed by arranging a plurality of meandering tubes in parallel so that their arrangement intervals are uniform and connecting them in series. The surface area of the heat transfer tube 14 per unit volume of the heat storage material 13 is substantially uniform in each part in the case 12. Each of the heaters 15 a to 15 f is formed in a meandering shape, and is arranged in parallel between the heat transfer tubes 14 so as to be orthogonal to each other. Both ends of the heat transfer tube 14, each of the heaters 15a to 15f, and each of the thermocouples 16a to 16f pass through the upper wall of the case 12 and are led out.

Next, the electrical connection of the heat storage control device 11 will be described. As shown in FIG. 3, the heat storage control device 1
1 includes a control device 21 including a CPU and the like. The power supply 22 and the thermocouples 16a to 16
16f, nighttime power storage timer 23 and storage temperature setting device 2
4 are connected to each other. The heaters 15a to 15f and the heat storage temperature display 25 are connected to the output side of the control device 21, respectively. The power supply 22 includes a nighttime power supply line (not shown) and a daytime power supply line (not shown). From the nighttime power supply line, nighttime power is supplied to each heater 15a according to a time-of-day lamp fee system and a heat storage adjustment contract. To 15f.

From the daytime power supply line, normal daytime power is supplied to the control device 21 and the heat storage temperature display 25 according to a metered light contract. The nighttime power storage timer 23 outputs a signal to the control device 21 to the start time and the end time of the nighttime power zone (for example, 22:00 to 8:00) in which nighttime power can be used. I do. The control device 21 controls each heater 1 based on the temperature of each part of the heat storage material 13 detected by each of the thermocouples 16a to 16f.
ON / OFF control is individually performed for each of 5a to 15f.
The heat storage temperature display 25 displays the temperature of each part of the heat storage material 26 detected by each of the thermocouples 16a to 16f.

Next, the operation of the heat storage control device 11 configured as described above will be described. In this embodiment, the heat storage temperature is previously set to 50 by the heat storage temperature setting unit 24.
It is set to 0 ° C.

When water is supplied from one end of the heat transfer tube 14 with the heat storage material 13 heated to 500 ° C. by midnight power,
This water is heated by the heat of the heat storage material 13 via the tube wall of the heat transfer tube 14, becomes steam, and is taken out from the other end of the heat transfer tube 14. The control device 21 monitors the temperature of each part of the heat storage material 13 with each of the thermocouples 16a to 16f, and individually controls ON / OFF of each of the heaters 15a to 15f based on the set heat storage temperature (500 ° C.). . That is, each of the heaters 15a to 15f has a corresponding thermocouple 16a to
The temperature of each part of the heat storage material 13 detected by 16f is 50
When the temperature is lower than 0 ° C., the current is supplied, and when the temperature reaches 500 ° C., the current is stopped.

For example, during normal heat storage and additional heating operation, only the heat storage material 13 that has not reached 500 ° C. is heated, and the heat storage material 13 that has reached 500 ° C. is not further heated. That is, the high temperature part and the low temperature part of the heat storage material 13 are not heated at the same time. Therefore, unlike the case where the entire heat storage material 13 is uniformly heated by the heater, the heat storage material 13 is uniformly heated even though the heat storage amount is uneven. Therefore, heat is efficiently stored without increasing the temperature difference between the heat storage material 13 near the water inlet side of the heat transfer tube 14 and the heat storage material 13 near the steam outlet. In addition, the heat storage material 13, especially the heat transfer tube 14
The heat storage material 13 in the vicinity of the steam outlet is not overheated, and deterioration due to thermal decomposition is prevented. Incidentally, when the temperature of the nitrate constituting the heat storage material 13 reaches about 600 ° C., thermal decomposition starts.

Therefore, according to the present embodiment, the following effects can be obtained. The inside of the case 12 is divided into a plurality of sections, and heaters 15a to 15f are arranged for each of the divided sections.
a to 15f so as to correspond to the thermocouples 16a to 16f, respectively.
6f was provided. Then, the control device 21 controls each thermocouple 16
The energization to each of the heaters 15a to 15f is individually controlled based on the temperature of each part of the heat storage material 13 detected at a to 16f. Therefore, the set heat storage temperature 500
Only the heater corresponding to the heat storage material 13 that has not reached
By making N, efficient heat storage can be performed. Since the heater corresponding to the heat storage material 13 having reached the set heat storage temperature 500 ° C. is de-energized, the heat storage material 1
3 is not heated until the nitrate decomposition onset temperature reaches 600 ° C. That is, it is possible to prevent the heat storage material 13 from being overheated. (Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. This embodiment differs from the first embodiment in that the number and arrangement of thermocouples and a plurality of heaters are controlled collectively. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will not be repeated. In the present embodiment, the heat storage temperature setting unit 24 previously sets the heat storage upper limit temperature to 550 ° C. This is determined based on the above-mentioned temperature 600 ° C. at which the thermal decomposition of nitrate starts.

As shown in FIG. 4, thermocouples 31a and 31b are provided near the center of the heat storage material 13 and the heater 15d which is closest to the steam outlet side of the heat transfer tube 14, respectively. The control device 21 controls the thermocouples 31a, 3
Based on the temperature of the heat storage material 13 detected in 1b, the respective heaters 15a to 15f are collectively controlled. That is, each of the heaters 15a to 15f is simultaneously turned ON / OFF.

For example, during the additional heating operation, when the temperature of the heat storage material 13 detected by the thermocouple 31a is less than 500 ° C. and the temperature of the heat storage material 13 detected by the thermocouple 31b is 550 ° C. or less, The control device 21 controls each heater 15a.
To 15f. When the temperature of the heat storage material 13 detected by the thermocouple 31b reaches a preset heat storage upper limit temperature of 550 ° C., the control device 21
The current supply to 5a to 15f is temporarily stopped.

Thereafter, the temperature of the heat storage material 13 is made uniform by the diffusion of heat, and the heat storage material 13 near the steam outlet of the heat transfer tube 14 is formed.
When the temperature becomes lower than the heat storage upper limit temperature 550 ° C., the control device 21 starts energizing the heaters 15a to 15f again. Control device 21 repeats ON / OFF to each of heaters 15a to 15f in the same manner as described above until the temperature of heat storage material 13 detected by thermocouple 31a reaches 500 ° C.

Therefore, according to the present embodiment, the following effects can be obtained. (1) When the temperature of the portion of the heat storage material 13 having a relatively large amount of residual heat, that is, the temperature of the heat storage material 13 near the steam outlet side of the heat transfer tube 14 reaches the heat storage upper limit temperature of 550 ° C., each of the heaters 15 a to 15.
The current supply to 5f was cut off. For this reason, the heat storage material 13 is not overheated, and deterioration of the heat storage material 13 due to thermal decomposition can be prevented.

(2) The heaters 15a to 15f are collectively controlled, that is, ON / OFF controlled simultaneously. Therefore, unlike the case where the heaters 15a to 15f are individually controlled to be turned on / off, there is no need to provide a breaker and an electric switch such as an electromagnetic switch for energization and de-energization for each of the heaters 15a to 15f. Therefore, simplification and miniaturization of the control device 21 are possible, and product cost can be reduced.

The above embodiments may be modified and implemented as follows. In the first and second embodiments, as shown in FIG.
The thermocouples 16a to 16f may be provided above the center of the heat storage material 13. In FIG. 5, the thermocouples 16d to 16d
16f is omitted. Generally, heat goes up and up,
In the heat storage material 13, the heaters 15a to 15a-15
f is ON / OFF controlled. For this reason, overheating of the heat storage material 13 can be prevented more effectively.

In the second embodiment, the thermocouples 31a, 3a are provided at the center of the heat storage material 13 and at the steam outlet side of the heat transfer tube 14, respectively.
Although 1b was provided, as shown in FIG. 6, if it is between the center of the heat storage material 13 and the steam outlet side of the heat transfer tube 14, that is, within a range of half of the heat storage material 13 on the steam outlet side of the heat transfer tube 14. ,
It may be provided at any position.

As shown in FIGS. 7A to 7C,
The shape and arrangement of the heat transfer tubes 14 may be arbitrarily changed. That is, the heat transfer tube 14 shown in FIG. 7A is formed in a meandering shape, and both ends thereof are led out from above and below the case 12. The heat transfer tube 14 shown in FIG. 7 (b) is formed in a meandering shape, and both ends thereof are led out from the mutually facing side walls of the case. The heat transfer tube 14 shown in FIG. 7C is composed of a plurality of tubes penetrating the case 12, and both ends of each tube are respectively connected to an inlet header and an outlet header. 7A to FIG.
As shown in (c), thermocouples 31a and 31b are arranged at least near the center of the heat storage material 13 and near the steam outlet side of the heat transfer tube 14 in the heat storage material 13, respectively. Even in this case, overheating of the heat storage material 13 can be prevented.

In the first embodiment, each thermocouple 16a-1
Although 6f is arranged in close proximity to each of the heaters 15a to 15f, the number of heaters and thermocouples may be arbitrarily changed. That is, the ratio “heater: thermocouple = 1: 1” between the heater and the thermocouple in the first embodiment is changed to, for example, “thermocouple: heater = 6: 3” and “thermocouple: heater =
9: 6 "or the like. In this case, the cost can be reduced unlike the case where a thermocouple is provided for each heater.

In the first embodiment, each of the heaters 15a to 15a
Although energization to f is individually controlled, it may be controlled collectively. In the second embodiment, the energization to the heaters 15a to 15f is controlled collectively, but may be controlled individually.

Next, technical ideas other than the claimed invention which can be understood from the above embodiments will be described. The heat storage control device according to any one of claims 1, 3, and 4, wherein the control means individually controls energization and interruption of energization to the heating means.

[0033]

According to the present invention, since the power supply of the heating means is controlled based on the temperature of the portion of the heat storage material having a relatively large amount of residual heat, overheating of the heat storage material can be prevented.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a heat storage control device according to a first embodiment.

FIG. 2 is a plan view of the heat storage control device according to the first embodiment.

FIG. 3 is a block diagram showing an electrical configuration of the heat storage control device according to the first embodiment.

FIG. 4 is a plan view of the heat storage control device according to the first embodiment.

FIG. 5 is a schematic front view of a heat storage control device according to another embodiment.

FIG. 6 is a schematic plan view of a heat storage control device according to another embodiment.

FIG. 7A is a schematic front view of a heat storage control device according to another embodiment. (B), (c) is a schematic plan view of the heat storage control apparatus in another embodiment.

[Explanation of symbols]

11: heat storage control device, 12: case, 13: heat storage material, 1
5a to 15f ... heater (heating means), 16a to 16f ...
Thermocouple (temperature detecting means), 21 ... control means.

Claims (5)

[Claims] 1. A heating means for heating a heat storage material filled in a case, a temperature detection means for detecting a temperature of the heat storage material,
A heat transfer tube arranged in the case and having a heat medium flow therein to perform heat exchange between the heat medium and the heat storage material,
Control means for controlling energization to the heating means based on the temperature of the heat storage material detected by the temperature detection means, wherein the temperature detection means is at least a heat medium outlet side of the heat transfer tube. A heat storage control device placed in a nearby heat storage material. 2. Heating means for heating the heat storage material filled in the case, temperature detecting means for detecting the temperature of the heat storage material,
A heat transfer tube arranged in the case and having a heat medium flow therein to perform heat exchange between the heat medium and the heat storage material,
A heat storage control device comprising: a control unit that controls energization to the heating unit based on the temperature of the heat storage material detected by the temperature detection unit. A heat storage control device in which a heating means is arranged, a temperature detecting means is provided so as to correspond to each heating means, and the control means individually controls energization to each heating means. 3. The heat storage control device according to claim 1, wherein the temperature detecting means is provided near a center of the heat storage material. 4. The heat storage control device according to claim 1, wherein the temperature detection unit is disposed above a center of the heat storage material. 5. The control device according to claim 1, wherein the control means controls energization and cutoff of the heating means collectively.
The heat storage control device according to claim 4.