JPS58160780A - 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 The present invention relates to an absorption refrigerator control device. An example of a conventional absorption refrigerator control device will be explained based on FIG. 1. The one shown in FIG. 1 is a double-effect absorption refrigerator that uses water as the refrigerant and an aqueous lithium bromide solution as the absorbent (solution).

In the figure, 1 is a high pressure regenerator, 2 is a low pressure regenerator, 3 is a condenser, 4 is an evaporator, 5 is an absorber, 6 is a low temperature heat exchanger, 7
1 is a high temperature heat exchanger, 8 to 13 are solution pipes, 14 is a regenerator pump, 15 is an absorber pump, 16 is an ejector 117
19 to 19 are refrigerant pipes, 20 is a refrigerant pump, 21 is a heating source pipe, 22ij is a cooling water pipe, 23 is a cold water pipe, 24d
It is a cooling water pump and is connected to the piping as shown in the figure, and the refrigerant evaporated in the high pressure regenerator 1 passes through the low pressure regenerator 2 and enters the condenser B, where it exchanges heat with the water in the cooling water piping 22 and is condensed and liquefied. Thereafter, the water enters the evaporator 4, exchanges heat with the water in the cold water pipe 23, and evaporates, and the heat removed at this time cools the water in the cold water pipe 23.

On the other hand, the refrigerant evaporated in the evaporator 4 is absorbed by a solution in the absorber 5, and the solution, which has absorbed the refrigerant and has become diluted, is sent to the pump 14, the low temperature heat exchanger 6, and the high temperature heat exchanger 7. Then, the heating source piping 21 is heated by a heating source supplied with red, and the refrigerant is evaporated and separated to become a medium concentration solution, which is then passed through the high-temperature heat exchanger 7 to the low-pressure regenerator. 2
The refrigerant enters and is heated by the refrigerant vapor, and the refrigerant is further evaporated and separated, increasing its concentration. The solution that has become highly concentrated in the low-pressure regenerator passes through the low-temperature heat exchanger 6, mixes with the solution from the absorber pump 15 in the ejector 16, and is sprayed into the absorber 5. I do.

Conventionally, in the above-mentioned dual-effect absorption refrigerator, a chilled water outlet temperature detector 25 detects the chilled water outlet temperature, and a comparator 27 compares this with a chilled water outlet temperature target value set in a temperature setting device 26. The flow control valve 29 is controlled via the flow rate regulator 28 to adjust the flow rate of the heating source, and the solution level in the high pressure regenerator 1 is detected by the liquid level detector 30, and the liquid level setting device and the liquid level setting device A comparator 32 compares the liquid level with a target liquid level set at 31, and controls a circulation rate control valve 34 via a circulation rate regulator 33 to control the circulation rate of the solution, so as to adapt to the load. It controls the capacity of the mechanism.

In the absorption chiller described above, if the amount of heat source and the amount of solution circulation are the same, there is a tendency that the lower the cooling water inlet temperature, the higher the efficiency. For example, when the cooling water inlet temperature decreases, the efficiency increases. However, with the conventional system described above, control can only be started after this effect appears on the chilled water outlet temperature, resulting in loss of heating energy, heat transfer delay, and transport There were problems such as poor controllability due to delays.

The present invention has been proposed in view of the above points, and its purpose is to provide an absorption chiller control device that can save energy and perform stable control with good followability. be.

The present invention provides a control system that detects the cold water outlet temperature and controls the amount of heat source to the regenerator, and a control system that detects the solution level in the regenerator and controls the solution circulation lid from the absorber to the regenerator. A system is installed, the cooling water inlet temperature is detected, and an appropriate value for at least one of the amount of heating source or the amount of solution circulation is determined as a function of the same temperature, and thereby the amount of heating source or the amount of solution circulating in both control systems is determined. According to the above, the cooling water inlet temperature is detected, and as a function of this temperature, at least either the heating source amount or the solution circulation amount is determined to be appropriate. It is possible to determine the value and use it as a feedforward signal to preliminarily control at least one of the amount of heat source and the amount of solution circulation. Here, efficiency increases as the cooling water inlet temperature decreases, so if the load remains the same, it means that the capacity of the machine can be increased or decreased by reducing the amount of heating source or the amount of solution circulation. By detecting the water inlet temperature and performing the above-described control using this as an index, it is possible to perform stable control with no energy loss and good followability to the operating state.

The present invention will be explained below based on illustrated embodiments.

In FIG. 2, reference numerals 1 to 64 indicate devices similar to the conventional device shown in FIG. 1, and perform the same functions.

In this embodiment, a temperature detector 101 for detecting the cooling water outlet temperature is further provided, and a function of the cooling water inlet temperature is determined based on a preset function based on the cooling water inlet temperature detected by this detector. Function generators 102 and 103 are provided to determine appropriate values for the heating source amount and the solution circulation amount, and comparators 104 and 103 are used to determine appropriate values for the heating source amount and solution circulation amount. 105, the heat source amount control valve 29 and the solution circulation amount control valve 34 are controlled.

In the above configuration, each of the function generators 102 and 103 is set with a predetermined appropriate function that increases the amount of heating source and the amount of solution circulation as the cooling water inlet temperature increases.

Here, if the cooling water inlet temperature rises or falls, the efficiency changes, and if the load remains the same, this means that the capacity of the machine can be increased or decreased by increasing or decreasing the amount of heating source or solution circulation. There is. On the other hand, when the old cooling water inlet temperature detector 1 detects the cold ship temperature and inputs it to the function generators 102 and 103,
The function generators 102 and 103 determine and output appropriate values for the amount of heat source and the solution circulation lid as a function of the cooling water inlet temperature based on a preset function.

Now, when the cooling water inlet temperature decreases, the efficiency increases, so the output of the function generators 102 and 103 decreases, reducing the amount of heating source and solution circulation, and conversely, when the cooling water inlet temperature increases, the efficiency increases. Since the temperature decreases, the amount of heating source and the amount of solution circulation are increased, and the amount of heating source and the amount of solution circulation are controlled in accordance with the cooling water temperature.

As described above, by using the PC cooling water inlet temperature as a feedforward signal for controlling the amount of heating source or solution circulation, stable control with good followability without energy loss can be realized.

In the above embodiment, an example was described in which both the amount of heat source and the amount of solution circulation were controlled simultaneously, but only one of them may be controlled.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing a conventional one, and FIG. 2 is a configuration diagram showing an embodiment of the present invention. 1: High pressure regenerator, 2: Low pressure regenerator, 3: Condenser, 4: Evaporator, 5: Absorber, 6: Low temperature heat exchanger, 7: High temperature heat exchanger, 8 to 13: Solution piping. 14: regenerator pump, 15: absorber pump, 16: ejector, 17 to 19: refrigerant piping, 20: refrigerant pump,
21: Heat source piping, 22: Cooling water piping, 23: Cold water piping, 24: Cooling water pump, 25: Cold water outlet temperature detector, 2
6: Temperature setting device, 27: Comparator, 28: Controller,
29: Heating source amount control valve, 30 = Liquid level detector, 31: Liquid level setting device, 32: Comparator, 33: Controller, 34:
Solution circulation amount control valve, 101: Cooling water inlet temperature detector, 102, 103: Function generator. 104, 105: Comparator

Claims (1)

[Claims] A control system that detects the chilled water outlet temperature and controls the amount of heat source to the regenerator, and a control system that detects the solution level in the regenerator and controls the amount of solution circulated from the absorber to the regenerator are installed. Detecting the inlet temperature and determining an appropriate value for at least one of the heating source amount and the solution circulation amount as a function of the same temperature, thereby controlling at least either the heating source amount or the solution circulation amount in both control systems. 1. An absorption chiller control device characterized by being provided with a control system for controlling the absorption chiller.