JPH0353543B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes a water heater attached to a high temperature regenerator, and the liquid refrigerant condensed in the water heater is also guided to the condenser and further dispersed in the evaporator to be supplied to the refrigeration cycle, thereby producing cold water for cooling. This invention relates to a control device for a dual-effect absorption chiller/heater that simultaneously supplies cold and hot water and is also used to obtain water.

Conventionally, a control device for this kind of absorption chiller/heater has been used to control cooling or heating depending on the combination of cold water and hot water load conditions, as disclosed in, for example, Japanese Patent Application Laid-open No. 55-118560 (Japanese Patent Application No. 54-26434). Since the main heating control is switched, and the fuel supply control, refrigerant flow rate control, and absorption liquid flow rate control are performed mainly for either cold water load or hot water load, the In this case, fuel supply control in particular became inappropriate, resulting in unreasonable and unstable control. In FIG. 1, for example, the chilled water load index is 25,
When the hot water load index is 80 (point A in Figure 1), the fuel control valve opening is set to 80, and main heating control is in progress.
When the cold and hot water load fluctuates as shown by the broken line arrow and reaches a cold water load index of 80 and a hot water load index of 25 (point 9 in Figure 1), the main heating control remains set under this load condition. Therefore, the opening degree of the fuel control valve is only 25, which has the drawback that fuel cannot be supplied to meet the chilled water load. Furthermore, when the hot water load index reaches 10 as shown by the broken line arrow (point C in Figure 1), the setting is such that the main control is switched to cooling under this load condition, so the fuel The control valve opening degree is 80, which has the disadvantage that the fuel supply increases rapidly, affecting the refrigerant flow rate and absorption liquid flow rate, making control unstable.

In view of this, the present invention supplies fuel by manipulating the opening degree of the fuel control valve in accordance with the total cold and hot water load, and controls the refrigerant by main control switching set depending on the combination of cold and hot water loads. The purpose of this system is to perform rational and stable control by operating each control valve.

Embodiments of the present invention will be described below based on the drawings. In Fig. 2, 1 is a high-temperature regenerator which has a combustion heating chamber 2 for city gas or kerosene, etc. and exhaust heat pipes 3, 3 from the heating chamber, and heats and separates the refrigerant from the dilute liquid to regenerate the intermediate liquid; 5 is a low-temperature regenerator that further heats and separates the refrigerant from the intermediate liquid by using refrigerant vapor sent from the high-temperature regenerator 1 to regenerate a concentrated liquid; 5 is a low-temperature regenerator that uses cooling water to condense the refrigerant flowing from the two regenerators 1 and 4; and an evaporator 6 which obtains cold water for air conditioning from a water cooler 7 by utilizing the latent heat when the liquid refrigerant from the condenser 5 is dispersed and vaporized.
8 is an absorber that maintains the inside of the evaporator 6 at a low pressure by dispersing the concentrated liquid from the low-temperature regenerator 4 and absorbing the refrigerant vapor in the container, thereby making it possible to continuously supply cold water; 9 and 10 are a low temperature heat exchanger and a high temperature heat exchanger, which are refrigerant vapor piping 11,
A refrigerant liquid down-flow pipe 12, a refrigerant circulation path 14 having a refrigerant pump 13, and a dilute liquid pipe 1 having an absorption liquid pump 15.
6. The intermediate liquid pipe 17 and the concentrated liquid pipe 18 are connected to form a refrigeration cycle. A water heater 19 is attached to the high-temperature regenerator 1 and exchanges heat with refrigerant vapor to supply hot water for heating. A refrigerant pipe 20 connects the lower part of the water heater 19 and the condenser 5.
, the refrigerant vapor piping 11 from the high temperature regenerator 1 to the condenser 5 via the low temperature regenerator 4, and the water heater 1.
A first refrigerant control valve CM1 and a second refrigerant control valve CM are installed in the refrigerant return pipe 21 connecting the high temperature regenerator 9 and the high temperature regenerator 1, respectively.
In addition to providing the second and third refrigerant control valves CM3, a fuel control valve CMG is provided in the heat source supply path 22 of the high temperature regenerator 1.

Reference numeral 23 denotes a cold water temperature detector, which detects the cold water outlet temperature of the water cooler 7 and controls the refrigerant through the hot junction H of the cold water side temperature regulator 24, first potentiometer CMP1, and cold/temperature changeover switch 25. control
Operate each of CM1, CM2, and CM3. 26
is a hot water temperature detector, which detects the hot water outlet temperature and controls the hot water side temperature regulator 27, second potentiometer CMP2 and cold/hot changeover switch 28.
The refrigerant control valve CM1 is operated through the cold contact C of the refrigerant control valve CM1. 29 is an addition controller, and in this controller,
The temperature of cold water corresponding to the cold water load is detected by the detector 23, and the temperature controller 24 and the first potentiometer are activated.
The detector 26 detects the control signal corresponding to the cold water load transmitted via the CMP 1 and the hot water temperature corresponding to the hot water load.
The hot water load corresponding control signal detected by the temperature controller 27 and transmitted via the second potentiometer CMP2 is added. The addition controller 29
The fuel control valve
The CMG is operated to supply fuel corresponding to the total cold and hot water load.

Next, the control operation in such a configuration will be explained.

(b) Cooling main control In principle, this applies to areas where the cooling load is greater than the heating load, specifically when the chilled water load index is 95 or more, and when the chilled water load index is 20 or more and the hot water load index is 20 or less (Figure 1). reference).

In this case, both cold and hot changeover switches 25 and 28 are closed to the cold junction C side, and the second refrigerant control valve CM2
is fully open, and the third refrigerant control valve CM3 is fully closed. Then, the hot water temperature detector 26 detects the hot water outlet temperature, and the first refrigerant control valve CM1 is proportionally operated via the hot water side temperature regulator 27 and the second potentiometer CMP2 to control the hot water temperature. In other words, the first refrigerant control valve CM1 is opened and closed by the control signal of the second potentiometer CMP2 in response to the increase or decrease in the hot water outlet temperature, that is, the increase or decrease in the hot water load.

On the other hand, the chilled water temperature is detected by the chilled water temperature detector 23, and a control signal is transmitted from the first potentiometer CMP1 via the chilled water side temperature regulator 24 in response to the increase or decrease in the chilled water outlet temperature, that is, the increase or decrease in the chilled water load; An addition controller 29 adds the control signal sent from the second potentiometer CMP2 in response to the hot water load, and proportionally operates the fuel control valve CMG in accordance with the addition control signal sent from the controller. .
In other words, the fuel control valve CMG is opened or closed in response to an increase or decrease in the total load of cold water and hot water. Then,
For example, in Fig. 1, when the load changes from point B to point C and the heating main control switches to the cooling main control, the fuel control valve CMG is opened in response to the change in the cold/hot water total load index from 105 to 90. The degree index is proportionally operated from 105 to 90, and stable control is achieved.

(b) Heating main control In principle, in areas where the heating load is greater than the cooling load, specifically the hot water load index when the chilled water load index is 95 or less.
This applies when the load index is 95 or higher, and when the cold water load index is 20 or lower and the hot water load index is 20 or higher (see Figure 1).

In this case, the cold/temperature changeover switches 25 and 28 are both closed to the hot junction H, the cold water temperature detector 23 detects the cold water outlet temperature, and the refrigerant is passed through the cold water side temperature regulator 24 and the first potentiometer CMP1. The control valves CM1, CM2, and CM3 are controlled in conjunction with each other, but at a chilled water temperature corresponding to a chilled water load index of 0 to 50, the first refrigerant control valve
CM1 is proportionally operated from fully closed to fully open, the second refrigerant control valve CM2 maintains the fully closed state, and the third refrigerant control valve
CM3 is operated proportionally from fully open to fully closed, and when the chilled water load index is between 50 and 100, the first refrigerant control valve CM1 maintains the fully open state regardless of the increase or decrease in the chilled water load.
The second refrigerant control valve CM2 is proportionally operated from fully closed to fully open, and the third refrigerant control valve CM3 maintains the fully closed state. On the other hand, the fuel control valve CMG is proportionally operated by an addition control signal transmitted from the controller 29 in accordance with the total load of cold and hot water. For example, when the load changes from point A to point B in FIG. 1, the third refrigerant control valve CM3 is operated in the closing direction to reduce the return of liquid refrigerant in the water heater 19 to the high temperature regenerator. The water heater 19 is controlled by controlling the hot water load and operating the first and second refrigerant control valves CM1 and CM2 in the opening direction.
The refrigerant flow rate from the high-temperature regenerator 1 to the condenser 5 is increased to perform control corresponding to the chilled water load, while the total cold/hot water load index remains unchanged at 105.
The fuel control valve opening degree is held constant. That is,
Rational and stable control is performed on the external load of the water cooler/heater.

(c) Control in the neutral region When the cold water load index and the hot water load index are 20 to 95 (see Figure 1), when transitioning from the cooling region to the neutral region, the cooling main control operation described in (a) above is performed, and the heating When transitioning from the area to the neutral area, the heating main control operation of (b) is performed.

(d) Control in the zero region When both the cold water load index and the hot water load index are 20 or less (see Figure 1), when transitioning from the cooling region to the zero region, the main cooling control turns combustion off, and the heating region changes to the zero region. When switching to , combustion is turned off by heating main control.

As described above, the present invention selectively switches the main control depending on the load conditions of cold water and hot water, and from the first refrigerant control valve provided in the refrigerant pipe leading from the water heater to the condenser, and the high temperature regenerator. While operating in conjunction with a second refrigerant control valve provided in a refrigerant vapor pipe leading to a condenser via a low-temperature regenerator, and a third refrigerant control valve provided in a refrigerant return pipe leading from a water heater to a high-temperature regenerator, Since the opening degree of the fuel control valve installed in the heat source supply pipe of the high-temperature regenerator is operated according to the total of the cold water load and the hot water load, it is determined whether the cold water load for cooling or the hot water load for heating is It is possible to perform rational fuel supply control even with such fluctuations, and it is possible to prevent the opening degree of the fuel control valve from changing significantly even when switching main control, and to perform stable control. .

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of capacity control for each main control switch, Figure 2
The figure is a block diagram of an absorption chiller/heater embodying the present invention, and FIG. 3 is an explanatory diagram of the operation of each control valve during main cooling control and main heating control in the embodiment of the present invention. 1...High temperature regenerator, 5...Condenser, 7...Water cooler, 19...Water heater, CM1, CM2, CM3...
...First, second, third refrigerant control valves, CMG...Fuel control valve.

Claims (1)

[Claims] 1 High temperature regenerator, low temperature regenerator, condenser, evaporator,
An absorber, a low-temperature heat exchanger, and a high-temperature heat exchanger are connected to form a refrigeration cycle, and a water heater is attached to the high-temperature regenerator, and the liquid refrigerant in the water heater is guided to the refrigeration cycle to produce cold water for cooling. In a dual-effect absorption chiller-heater of the type that simultaneously supplies cold and hot water, which is also used for supply, a first refrigerant control valve is provided in the refrigerant piping from the water heater to the condenser, and the first refrigerant control valve is connected to the condenser from the high-temperature regenerator through the low-temperature regenerator. A second refrigerant control valve is provided in the refrigerant vapor pipe leading to the water heater, a third refrigerant control valve is provided in the refrigerant return pipe leading from the water heater to the high temperature regenerator, and a fuel control valve is provided in the heat source supply pipe of the high temperature regenerator. The opening degree of the fuel control valve is operated according to the total of the load and the hot water load, and the main control is selectively switched depending on the load conditions of cold water and hot water, and the refrigerant control valve is operated in conjunction with the main control. A control device for a dual-effect absorption chiller/heater.