JPS58203358A - Controller for absorption type cold and hot water machine utilizing solar heat - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a solar heat absorption type water chiller/heater that uses low-temperature water heated by solar heat as a main heat source and steam or fuel as an auxiliary heat source.

In conventional solar heat absorption type water chillers/heaters, low-temperature water from a heat collector or a heat storage tank is supplied to a low-temperature heat source generator whose heat source is low-temperature water heated by solar heat. At this time, measures are taken to introduce low-temperature water based on the relative temperature of the solution in the low-temperature heat source generator and the low-temperature water. According to this strategy, if the temperature of the low-temperature water is extremely high and the solution temperature in the low-temperature heat source generator is low, a relatively large amount of heat will be instantly input by the low-temperature water. Since there is a limit to the amount of heat exchange between the solution and the low-temperature water in the low-temperature heat source generator, the heat amount of the low-temperature water does not transfer to the solution side, and the low-temperature water without sufficient heat exchange is directly transferred to the heat collector or heat storage tank. will be returned to.

For this reason, heat loss in the pipes along the way, loss of mixing of the original low-temperature water due to returning low-temperature water, etc. may occur. On the other hand, if the temperature of the low-temperature heat source generator is too low, adding low-temperature water will only raise the temperature of the solution, causing the temperature of the low-temperature water to drop rapidly, and then adding low-temperature water However, there was a risk that this would not be utilized in terms of refrigeration output.

SUMMARY OF THE INVENTION An object of the present invention is to provide a control device for a solar heat absorption type water chiller/heater that makes maximum use of low temperature water heated by solar heat and saves energy by effectively utilizing an auxiliary heat source.

The present invention is characterized by a low-temperature heat source generator that uses low-temperature water heated by solar heat as a heating source, and an absorption generator that includes a high-temperature generator and a low-temperature generator that use an auxiliary heat source as a heating source when solar heat is insufficient. , 6 water heater, in which the amount of heat input to low-temperature water is controlled according to the temperature of the low-temperature heat source generator.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a system diagram of the solar heat absorption type water chiller/heater of the present invention. The cold/hot water machine includes a high-temperature generator 2 that heats a dilute solution using an auxiliary heating source 1 to generate refrigerant vapor (steam), and a high-temperature generator 2 that heats the dilute solution with the refrigerant vapor generated by the high-temperature generator 2 to generate refrigerant vapor. a low-temperature heat source generator 5 that generates refrigerant vapor (steam) by heating a dilute solution with low-temperature water in a low-temperature water pipe 4 heated by solar heat; A low-temperature water pump 6 that feeds into the heat source generator 5, a condenser 8 that cools and liquefies the refrigerant vapor generated by the generators 2 and 3 with cooling water passing through the cooling water pipe 7; An evaporator 10 that evaporates the liquefied refrigerant liquid and extracts the latent heat of vaporization from the water flowing in the cold water pipe 9 to generate cold water (cold power), and evaporates while being cooled by the cooling water flowing in the cooling water pipe 7. An absorber 11 absorbs the refrigerant vapor evaporated in the absorber 10 into a concentrated solution introduced from the generators 2 and 3.5 to generate a dilute solution, and an absorber 11 absorbs the refrigerant vapor evaporated in the absorber 10 into a concentrated solution introduced from the generators 2 and 3.5 to generate a dilute solution. .5, a high temperature heat exchanger 13 and a low temperature heat exchanger that exchange heat between the dilute solution sent from the absorber 11 to the generator and the concentrated solution returned from the generator to the absorber 11. 14, and a refrigerant pump 15 that circulates the refrigerant in the evaporator 10. Furthermore, the solar heat absorption type water cooler/heater of the present invention includes a supply source 16 of low temperature water heated by solar heat such as a heat storage tank or a heat collector, and a valve 17 for adjusting the amount of low temperature water in the low temperature water pipe 4. . 18 is a detector for detecting the solution temperature of the low-temperature heat source generator 5; 19 is a detector for detecting the outlet temperature of the low-temperature water; 20 is a detector for detecting the inlet temperature of the low-temperature water; 21 is a detector for detecting the inlet temperature of the low-temperature water; This is a detector that detects the temperature of a high temperature section. The control device 22 includes the temperature detector 18,
Based on the detection signals of
and controls valve 17.

The operation of the first embodiment of the control device 22 of the present invention described above will be explained with reference to FIG.

FIG. 2 shows what control measures are taken based on the relative relationship between the solution temperature in the low temperature heat source generator 5 and the low temperature water temperature. The horizontal axis is the solution temperature.

In LT, L indicates its practical upper limit.

The vertical axis is the low temperature water temperature HT, a is its practical lower limit, b
indicates the practical upper limit, and C indicates the upper limit. On the other hand, in order for the low-temperature water to impart heat to the solution, the low-temperature water temperature HT and the solution temperature LT must at least be equal. This relationship is evaluated by the straight line in the figure. However, in practice, the low temperature water temperature HT must be somewhat higher than the solution temperature. This relationship is evaluated by the straight line in the figure.

This relationship is stored within the control device 22. Based on the above relationship, the four regions I to ■ shown in the figure are determined, and the following control measures are executed according to each region ■ to ■ set by the detection values of each detector 18 to 21. do. That is, in the case of falling under Region I, that is, when the low temperature water temperature is extremely high, even if a large amount of low temperature water is introduced into the low temperature heat source generator 5, the calorific value of the low temperature water is not sufficiently transferred to the solution.
Since it is returned to the heat storage tank 16 as it is, there is a risk of heat loss due to heat dissipation or mixing during the process. Therefore, it is better to limit the amount of heat input by low-temperature water. As a concrete measure for this, as shown in FIG. 1, it is possible to reduce the flow rate of low-temperature water to the generator 5 using the valve 17, and to reduce the discharge capacity of the low-temperature water pump 6. By this measure, sufficient heat can be inputted by low-temperature water to reliably raise the temperature of the solution, and the efficiency of utilization of low-temperature water can be increased so as not to cause heat loss.

In the case of falling under the region π, that is, when the temperature of the low-temperature water is relatively high, the heat amount of the low-temperature water is effectively transferred to the solution, so the valve 17 is controlled to be fully open, or the capacity of the low-temperature water pump 6 is Control by one arm.

If it falls under region ■, that is, if the temperature of the low-temperature water is low, we cannot expect much effect from adding low-temperature water, but since the temperature of the solution is also low, the valve 17 and low-temperature water pump 16 can be controlled as necessary. and add low temperature water.

In the case of region (3), that is, when the temperature of the solution is high, the low-temperature water pump 6 is controlled to stop, since adding low-temperature water will result in a loss. At this time, by driving the pumps 12 and 15 to forcibly circulate the solution and refrigerant, or by forcibly supplying the low-temperature solution to the low-temperature heat source generator 5, the solution temperature can be lowered below the low-temperature water temperature. It is also possible to add low-temperature water.

Next, the operation of the second embodiment of the control device of the present invention will be explained with reference to FIG. FIG. 3 is based on the relative relationship between the solution temperature LT of the low temperature heat source generator 5 and the low temperature water temperature HT.
It shows what kind of control measures to take. The horizontal axis is the solution temperature LT, and Lpa indicates its practical upper limit.

The vertical axis is the low-temperature water temperature) (T, where a' is the practical lower limit and c/ is the upper limit. On the other hand, in order for the low-temperature water to give the solution heat, at least the low-temperature water temperature must be and the solution temperature must be equal. This relationship is evaluated by ′ on the straight line in the figure. However, in practice, the low temperature water temperature H
T must be higher than the solution temperature LT to some extent. This relationship is evaluated by ′ on the straight line in the figure. moreover,
The case where the low temperature water temperature HT is considerably higher than the solution temperature LT is evaluated using the straight line m in the figure. Based on the above relationship, the control device 22 determines the four areas 1' to ■' as shown in the figure, and selects the next area according to the detection values of the detectors 18 to 21. Implement control measures such as

In other words, in the case of area work I, that is, when the low temperature water temperature is extremely high, even if a large amount of low temperature water is poured into the low temperature heat source generator 5, the heat amount of the low temperature water will not be sufficiently transferred and will remain as it is. Since it is returned to the heat storage tank 16, there is a risk of heat loss due to heat radiation or mixing during the process. Therefore, the input of heat by low-temperature water is temporarily suspended, and the solution is first efficiently heated by the auxiliary heating source 1, and the operating state of the entire refrigerator is shifted to near the rated state, and the temperature of the solution rises, causing the solution to freeze. Only after the machine is able to smoothly produce cooling power (9) will we begin to input heat using low-temperature water. With this measure, sufficient heat can be inputted by low temperature water to reliably raise the temperature of the solution, and the efficiency of using low temperature water without heat loss can be increased.

In the case of region ■′, that is, when the temperature of the low-temperature water is relatively high, the heat amount of the low-temperature water is effectively transferred to the solution, so the valve 17 is controlled to be fully open, or the capacity of the low-temperature water pump 6 is is largely controlled.

If it falls under region ■', that is, if the temperature of the low-temperature water is low, no significant effect can be expected from adding low-temperature water, but since the temperature of the solution is also low, valve 17 and low-temperature water pump I6 should be turned on as necessary. is controlled and low-temperature water is added.

In the case corresponding to the region (■'), that is, when the temperature of the solution is high, the low-temperature water pump 6 is stopped, since adding low-temperature water will result in a loss. At this time, by driving the pump 12.15 to forcibly circulate the solution or refrigerant, or by forcibly supplying the low-temperature solution to the low-temperature heat source generator 5, the temperature of the low-temperature water can be lowered by (10). It is also possible to lower the solution temperature so that low-temperature water can be introduced.

In the above embodiments, the explanation has been given of the case where the refrigeration output, that is, the output of cold water, is provided, but the present invention can also be applied to the case where the output of the heating output, that is, the output of hot water. When generating heating output, low-temperature water heated by solar heat is passed through the evaporator 10 to the low-temperature heat source generator 5.
It can also be applied to a solar heat absorption type heat pump that pumps up heat source water passed through a low temperature heat source generator 5 or a main heat source, and produces hot water using heat source water passed through a low temperature heat source generator 5 or a main heat source.

As described above, according to the present invention, the heat amount of the low-temperature water can be effectively transferred to the solution depending on the relative temperature of the solution in the low-temperature heat source generator and the low-temperature water. Therefore, not only can solar heat be used effectively, but additional heating sources can be saved, thereby increasing the energy saving effect.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of a solar heat absorption type water chiller/heater (11) equipped with the control device of the present invention, and FIGS. 2 and 3 are explanatory diagrams showing examples of control operations in the control device of the present invention. 1... Auxiliary heat source, 2... High temperature generator, 3... Low temperature generator, 4... Low temperature water pipe, 5... Low temperature heat source generator, 6... Low temperature water pump, 7... ...Cooling water pipe, 8...
Condenser, 9... Cold water pipe, 10... Evaporator, 11...
・Absorber, 12... Solution pump, 13.14... Heat exchanger, 15... Refrigerant pump, 16... Heat storage tank, 1
7... Valve, 18-21... Temperature detector, 22...
Control device. 17 (12)

Claims (1)

[Claims] 1. Absorption device equipped with a low-temperature heat source generator that uses low-temperature water heated by solar heat as a heating source, and a high-temperature generator and a low-temperature generator that use an auxiliary heating source as a heating source when solar heat is insufficient. A solar heat utilization system characterized in that the type water chiller/heater is equipped with a control part that controls the amount of heat input to the low temperature heat source generator according to the relative temperature of the solution in the low temperature heat source generator and the low temperature water. Control device for absorption type water chiller/heater. 2. The control device for a solar heat absorption type water chiller/heater according to claim 1, wherein the control unit controls the amount of heat input to the low temperature heat source generator according to the temperature of the low temperature water. . 3. The control device for a solar heat absorption type water cooler/heater according to claim 2, wherein the control unit controls the flow rate of low-temperature water. 4. The control device for a solar heat absorption type water chiller/heater according to claim 1, wherein the control unit controls the temperature of the low temperature heat source generator using an auxiliary heating source according to the input heat amount of the low temperature water. . 5. Solar heat utilization according to claim 1, wherein the control unit controls the temperature of the low-temperature heat source generator according to the input heat amount of low-temperature water by the amount of circulation thereof by driving a solution pump and a refrigerant pump. Control device for absorption type water chiller/heater.