JPS6033464A - Controller for absorption refrigerator - 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 (a) Industrial Application Field The present invention relates to a control device for an absorption chiller that extracts chilled water in accordance with the load, and particularly to an absorption chiller in which a plurality of load-side heat exchangers are installed in parallel. The present invention relates to a control device.

(B) Conventional technology Conventionally, in an absorption refrigerator, an increase or decrease in load is detected by a detector that senses the temperature of cold water taken out from the evaporator, and the signal from this temperature detector is used to determine the opening of the heat source control valve of the generator. Means for controlling the temperature of cold water supplied to the load-side heat exchanger by adjusting the temperature is known.

However, with this conventional method, when the load suddenly decreases, there is a time delay until the detector detects the change in temperature of the chilled water and operates the heat source control valve, so during that time the load is This has the disadvantage that the heat input to the absorption refrigerator becomes excessive and the temperature of the chilled water becomes too low.

Therefore, in absorption chillers where multiple load-side heat exchangers are installed in parallel, if the number of load-side heat exchangers in operation is suddenly reduced, conventional means alone cannot prevent the excessive drop in chilled water temperature. The problem was that I couldn't get it.

(c) Purpose of the Invention The present invention provides a control device that can prevent an excessive drop in chilled water temperature even when the load suddenly decreases in an absorption chiller in which a plurality of load-side heat exchangers are installed in parallel. The purpose is to

B) Structure of the Invention The present invention preferentially adjusts the maximum opening degree of the heat source control valve of the generator according to the number of load-side heat exchangers in operation using the start/stop signal of the load-side heat exchangers, and The opening of the heat source control valve is adjusted based on a signal from a detector that detects the temperature of the cold water outlet of the absorption refrigerator.

According to the present invention, for example, when the number of operating load-side heat exchangers is halved and the load is suddenly halved, the maximum opening degree of the heat source control valve is preferentially adjusted to 50%. That is, when the load is suddenly halved, the heat input to the absorption refrigerator is immediately halved for the halved load.

Therefore, according to the present invention (3), even when the load suddenly decreases, it is possible to prevent excessive heat input to the absorption chiller relative to the load, and it is possible to prevent the chilled water temperature from decreasing excessively. can.

(E) Embodiment FIG. 1 is a schematic structural diagram showing an embodiment of the control device of the present invention. In Figure 1, (1) is a generator, (2)
is a condenser, (3) is an evaporator, (4) is an absorber, and (5) is a solution heat exchanger. Tube (9) with pump (8) for recirculating the liquid, tube (1) with solution pump 00)
1) They are connected by a pipe through which the solution flows down to form an absorption refrigeration cycle by circulating the refrigerant and absorption liquid.

(I3) is a water cooler built into the evaporator (3), (14)
is a heater built into the generator (1), (1 clause and Oe
is a cooler built into the absorber (4) and condenser (2).

, O8, and Ql are the first, second, and third load-side heat exchangers, respectively.

(2 (LCI!)) are the first and second cold water headers, respectively. C21 is a cold water pump with a cold water pump (c) that connects the water cooler 031 and the first and second cold water headers (20), 01). The main pipes (24), (c), and (c) are the first and second cold water headers, (21) and the first, second, and third load side heat exchangers 0η and QL O, respectively. The first, second, and third cold water pipes (27) connected in parallel are heat source pipes with heat source control valves that connect the boiler or other heat source equipment (not shown) and heater 0 (a). (to) is the cooling water pipe. (Sl is a temperature detector that senses the temperature on the outlet side of the cold water cooler, that is, the temperature of the cold water taken out from the evaporator (3), and the signal of this temperature detector is sent to the temperature controller (C+).
vc is transmitted.

(C7) is a controller with a built-in computer, and this controller controls the signals of the temperature controller (C1) and the first, second, third
The load-side heat exchanger 07) receives on-off signals from the air conditioner (for example, on-off signals from a blower (not shown) built into the load-side heat exchanger), and processes these signals to generate a heat source. A control signal is sent to the control valve M.

Next, the operation of the control device of the present invention configured as described above will be explained. Here, in order to simplify the explanation of the operation of the control device, the rated capacity for heat exchange of the first load heat exchanger (17) is 10 refrigeration tons, and that of the second load heat exchanger (marked 0) is 2 tons.
0 refrigeration tons, the third load side heat exchanger (II) has a rated refrigeration capacity of 30 refrigeration tons, and the rated refrigerating capacity of the absorption refrigerator is 60 refrigeration tons.

(Al) When all the load-side heat exchangers are operating In this case, the controller (C2) receives the operation signals from the first, second, and third load-side heat exchangers 0η, QgJ, and 01. Then, it is determined that this signal amount is the rated value.In other words, it is determined that the signal amount is equivalent to 60 refrigeration tons, and the maximum opening degree of the heat source control valve M is set to 100%. (C7) receives a signal from the temperature detector (Sl) via the temperature regulator (C1), and sends a control signal to the heat source control valve (M) while detecting an increase or decrease in load. The opening degree is adjusted as shown in Fig. 2. In Fig. 2, the vertical axis represents the opening degree [%], and the horizontal axis represents the load [%].

As can be seen from FIG. 2, the control operation when all the load-side heat exchangers are in operation is substantially the same as the operation in the conventional control device.

(B) Case where some of the load-side heat exchangers are stopped In this case, the description will be made assuming that, for example, the third load-side heat exchanger a1 is stopped.

In this case, the controller (C1) receives operation signals from the first and second load-side heat exchangers Q7) and (I mallet) and also receives a stop signal from the third load-side heat exchanger θ value. , determines that the signal amount is half of the rated value.In other words, determines that the signal amount is equivalent to 30 tons of refrigeration 17, and sets the maximum opening degree of the heat source control valve M to 50%. The control valve (■) is set from fully open to half open at the same time as the third debt side heat exchanger (1 sickle) is stopped by a control signal from the controller (C7). C1
) 17 receives a signal from the temperature detector (81) and sends a control signal to the heat source control valve (■) while detecting an increase or decrease in zero load.Then, the opening degree of the heat source control valve (■) is determined as shown in Figure 3. 2L shown in
Sea urchins are adjusted. In Figure 3, the vertical axis is the opening degree [%]
, the horizontal axis represents load [%].

In this way, when the third load side heat exchanger 09 is stopped and the load is reduced by half [7], the heat source control valve (■ is immediately changed from fully open to half open, and the heating needle of the generator (1) is also changed. Since it is immediately adjusted to half, the refrigerating capacity of the absorption chiller will not become excessive for the load.

That is, even if a meeting in a conference room (not shown) in which the third load-side heat exchanger 09 is installed ends and the operation of this heat exchanger is stopped, the first and second load-side heat exchangers 09 Exchanger (
17) and 08) can be prevented from becoming temporarily too cold in the offices (not shown) in which they are installed.

In addition, as the room temperature in the office gradually decreases as the air temperature decreases, i.e., the cooling load in the office gradually decreases, the temperature at the chilled water outlet of the absorption chiller also begins to decrease, so the temperature detector (
The heat source control valve M is controlled in the closing direction by the signal 81, and chilled water corresponding to the cooling load is supplied to the first and second load-side heat exchangers α power,
It will be supplied to 08.

FIG. 4 is a diagram showing another embodiment of the control device of the present invention, in which components similar to those in FIG. 1 are given the same figure numbers. In Figure 4, the wires are heat storage tanks, (Pl), (P2)
, (P3) are the first, second, and third cold pumps, respectively.

In FIG. 4, the controller (C1) receives start/stop signals for the first, second, and third cold water pumps (P, ), (pt), and (P3), and responds according to the number of operating cold water pumps. The maximum opening degree of the heat source control valve M is set using the heat source control valve M.

(F) Effects of the Invention As described above, when the load suddenly decreases due to a decrease in the number of load-side heat exchangers in operation, the control device of the present invention adjusts the heat source control valve to the maximum value according to the number of load-side heat exchangers in operation. Since the opening degree is set, it is possible to prevent excessive heat input to the absorption chiller for nine loads, and it is possible to prevent an excessive drop in the temperature of the chilled water. Moreover, since the temperature of the cold water taken out from the evaporator is sensed and the opening degree of the heat source control valve is adjusted, cold water suitable for the load can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration explanatory diagram showing one embodiment of the control device of the present invention, FIGS. 2 and 3 are explanatory diagrams showing an example of the operation of the heat source control valve in the control device of the present invention, and FIG. 4 is an explanatory diagram of the present invention. FIG. 3 is a schematic configuration explanatory diagram showing another embodiment of the control device. (1)...generator, (3)...evaporator, (17
), (IL ell...first, second, third load side heat exchanger, (CI)...temperature regulator, (C6)...controller, (P,), (P,) , (P3)...first, second,
Third cold water pump, (81...Temperature detector, ■...
・Heat source control valve. Figure 1- Figure 2 Figure 3'°°[-[2] 40th J'

Claims (1)

[Claims] (1) In an absorption chiller in which multiple load-side heat exchangers are installed in parallel, the opening degree of the generator heat source control valve is adjusted based on the signal from the temperature detector that detects the temperature of the cold water taken out from the evaporator. A control device for an absorption chiller, characterized in that the maximum opening degree of the heat source control valve is adjusted according to the number of operating load-side heat exchangers based on the start/stop signal r of the load-side heat exchangers. .