JPH08320168A - Control method for absorption type cold/hot water machine - Google Patents

Abstract

PURPOSE: To improve controllability and prolong the life of an apparatus by interrupting combustion in a regenerator based on the temperature of warm water discharged from an evaporator and restarting the combustion in the regenerator based on the temperature of hot water refluxing to the evaporator. CONSTITUTION: After combustion of a gas burner 1B of a high temperature regenerator 1 is restarted, a temperature sensor 29 detects temperature of hot water discharged from an evaporator 4 each predetermined time, and when the detected temperature exceeds predetermined set temperature plus first predetermined temperature, a heating quantity control valve 25 is closed and combustion of the gas burner 1B is interrupted. After the combustion of the gas burner 1B is interrupted, a temperature sensor 30 detects temperature of hot water refluxed to the evaporator 4 each predetermined time, and when the detected temperature becomes lower than temperature yielded by subtracting a second predetermined temperature from the detected temperature by the temperature sensor 30 that is stored in a RAM 37, the heating quantity control valve 25 is opened and the combustion of the gas burner 1B is restarted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption chiller-heater, and more specifically, to improve controllability and reduce the frequency of stopping / restarting combustion operation in a regenerator that evaporates and separates a refrigerant to reduce the life of the apparatus. The present invention relates to an absorption chiller-heater that is extended.

[0002]

2. Description of the Related Art There is a temperature of a heat-operated fluid which is cooled or heated to be taken out from an evaporator and circulated and supplied to a cooling / heating load by an endothermic action caused by evaporation of a refrigerant liquid or a heat dissipation action caused mainly by condensation of a refrigerant vapor. In order to keep the temperature within the temperature range, capacity control is generally performed by the outlet temperature of the thermally operated fluid taken out from the evaporator.

[0003]

However, in the conventional capacity control described above, the stop / restart control of the combustion for evaporating and separating the refrigerant in the regenerator is also controlled based on the evaporator outlet temperature of the heat-operated fluid. There is. Therefore, especially in a 2-position control device that simply repeats stop and full open, and a 3-position control device that controls stop / intermediate / full open, the capacity change due to the stop / restart of combustion is large, and a temperature sensor is installed on the evaporator outlet side. However, there is a problem that the stop / restart operation of combustion is frequently performed because it is directly affected by the influence, and not only the controllability but also the life of the apparatus is shortened, and the solution to this point has been a problem.

[0004]

As a concrete means for solving the above-mentioned problems of the prior art, the present invention constitutes a refrigerating cycle by connecting a regenerator, a condenser, an evaporator, an absorber and the like by piping. Absorption-type cold / hot water that cools or heats the required thermal operation fluid by the endothermic effect due to the evaporation of the refrigerant liquid in the evaporator or the heat dissipation effect mainly due to the condensation of the refrigerant vapor, and circulates and supplies this thermal operation fluid to the required equipment. In the machine

Combustion in the regenerator is stopped based on the temperature of the heat operating fluid discharged from the evaporator, and combustion in the regenerator is restarted based on the temperature of the heat operating fluid returning to the evaporator. Control method of the configuration of

In the control method of the first configuration, the temperature of the heat-operated fluid that has cooled and recirculated to the evaporator is recirculated to the evaporator when the previous combustion in the regenerator was stopped. A second control method for restarting combustion in the regenerator when the temperature of the heat-operated fluid + a predetermined temperature or higher;

In the control method of the first configuration, the temperature of the heat-operated fluid that is heated and is returned to the evaporator is returned to the evaporator when the previous combustion in the regenerator was stopped. A temperature of the heat-operated fluid-a control method of a third configuration for restarting combustion in the regenerator when the temperature exceeds a predetermined temperature;

In the control method of the first configuration, in the regenerator, when the temperature of the heat-operated fluid that is cooled and is discharged from the evaporator is equal to or higher than a set temperature−first predetermined temperature + second predetermined temperature. When the temperature of the heat-operated fluid discharged from the evaporator after starting combustion becomes equal to or lower than the set temperature minus the first predetermined temperature, the combustion in the regenerator is stopped and the heat returned to the evaporator is returned. Fourth, restarting combustion in the regenerator when the temperature of the operating fluid is equal to or higher than the temperature of the thermal operating fluid that has returned to the evaporator when the previous combustion in the regenerator was stopped + the second predetermined temperature Control method of the configuration of

In the control method of the first configuration, in the regenerator, when the temperature of the heat-operated fluid that is heated and is discharged from the evaporator is equal to or lower than a set temperature + first predetermined temperature−second predetermined temperature. After the heating is started, the combustion in the regenerator is stopped when the temperature of the heat-operated fluid discharged from the evaporator becomes equal to or higher than the set temperature + the first predetermined temperature, and the heat is returned to the evaporator. Fifth, the combustion fluid in the regenerator is restarted when the temperature of the operation fluid becomes equal to or lower than the temperature of the thermal operation fluid that has recirculated to the evaporator when the previous combustion in the regenerator has stopped-the second predetermined temperature. And a method of controlling the configuration of (1) above are provided to solve the above-described problems of the related art.

[0010]

[Function] The path from the evaporator outlet to the temperature detecting portion of the heat-manipulating fluid flowing back to the evaporator is long, and the amount of the heat-manipulating fluid held therein is sufficient so that combustion in the regenerator is turned on / off. Since it is not easily affected by the change in capacity, and the restart of the combustion is performed based on the temperature of the heat-operated fluid that is returned to the evaporator reflecting the magnitude of the cooling / heating load,
Not only is the controllability improved, but the frequency of stopping / restarting combustion is reduced and the device life is extended.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. The one illustrated in FIG. 1 is a dual-effect absorption refrigerator as a chiller-heater that circulates cold water or hot water in a load, and water is used as a refrigerant and lithium bromide (Li) is used as an absorbent.
Br) An aqueous solution is used.

In the figure, 1 is a high temperature regenerator equipped with a gas burner 1B, 2 is a low temperature regenerator, 3 is a condenser, 4 is an evaporator, 5 is an absorber, 6 is a low temperature heat exchanger, and 7 is a high temperature heat exchange. Container, 8 to 11 are absorption liquid pipes, 13 is an absorption liquid pump, 14
Reference numeral 17 is a refrigerant pipe, 19 is a refrigerant pump, 22 is cold water or hot water for circulating cold or hot heat to a cooling / heating load (not shown), and cold / hot water pipe provided with an evaporator heat exchanger 4A on the way, and 23 is A cooling water pipe provided with an absorber heat exchanger 5A and a condenser heat exchanger 3A on the way, 24 is a gas supply pipe connected to the gas burner 1B, 25 is a heating amount control valve provided on the way of the gas supply pipe 24, 26 28 are on-off valves,
Each of these devices is connected by piping as shown in FIG. 1, and the configuration itself is well known in the art.

That is, in the double-effect absorption refrigerator having the above-mentioned structure, the on-off valves 26, 27 and 28 are closed, the cooling water is passed through the cooling water pipe 23, the gas burner 1B is ignited, and the high temperature regenerator 1 discharges the solution. When heated, the refrigerant evaporated and separated from the solution in the high temperature regenerator 1 flows through the refrigerant pipe 14, and the low temperature regenerator 2
The intermediate absorption liquid is heated and condensed in the condenser 3 to enter the condenser 3, and the refrigerant separated from the intermediate absorption liquid in the low temperature regenerator 2 flows to the condenser 3,
After heat exchange with the water flowing from the cooling water pipe 23 to the condenser heat exchanger 3A to condense and liquefy, it flows together with the refrigerant from the refrigerant pipe 14 to the evaporator 4 via the refrigerant pipe 15.

In the evaporator 4, the refrigerant liquid is the evaporator heat exchanger 4
At A, the water from the hot / cold water pipe 22 is heat-exchanged and evaporated, and the heat of vaporization at this time cools the water flowing in the evaporator heat exchanger 4A. Then, the refrigerant evaporated in the evaporator 4 flows into the absorber 5 and is absorbed by the absorbing liquid sprayed from above.

Absorber 5 whose concentration is reduced by absorbing the refrigerant
The absorption liquid of 1 is sent to the high temperature regenerator 1 through the low temperature heat exchanger 6 and the high temperature heat exchanger 7 by the operation of the absorption liquid pump 13.
The absorbing liquid that has entered the high-temperature regenerator 1 is heated by the gas burner 1B to evaporate the refrigerant, and becomes a medium-concentration absorbing liquid that enters the low-temperature regenerator 2 via the high-temperature heat exchanger 7. Then, the absorption liquid is heated here by the refrigerant vapor flowing from the high temperature regenerator 1 through the refrigerant pipe 14, and the refrigerant is evaporated and separated to have a high concentration. The high-concentration absorbent flows through the low-temperature heat exchanger 6 to the absorber 5, and is sprayed from above.

When the absorption refrigerator is operated as described above, cold water cooled by the heat of vaporization of the refrigerant in the evaporator 4 can be circulated and supplied to the cooling / heating load (not shown) through the cold / hot water pipe 22, Can perform cooling operation.

On the other hand, when the open / close valves 26, 27, 28 are opened, the gas burner 1B is ignited without heating the cooling water through the cooling water pipe 23 and the solution is heated by the high temperature regenerator 1, the high temperature regenerator 1
The refrigerant evaporated in 2 enters the absorber 5 / evaporator 4 from the middle of the refrigerant pipe 14 mainly through the refrigerant pipe 17 having a small flow resistance, and is condensed by exchanging heat with the water in the evaporator heat exchanger 4A. The water flowing in the evaporator heat exchanger 4A is heated mainly by the heat of condensation at this time. Therefore, heating operation is performed by circulatingly supplying this hot water to a cooling / heating load (not shown).

The refrigerant condensed in the evaporator 4 is used as the on-off valve 2.
8 and flows to the absorber 5, is mixed with the absorbing liquid flowing from the absorbing liquid pipe 11, and is driven by the absorbing liquid pump 13 to pass through the low temperature heat exchanger 6 and the high temperature heat exchanger 7 and then to the high temperature regenerator 1.
Sent to. The absorbing liquid that has entered the high temperature regenerator 1 is heated by the gas burner 1B to evaporate the refrigerant, and becomes an absorbing liquid of medium concentration, and returns to the absorber 5 from the absorbing liquid pipe 11.

Reference numeral 31 is a control device provided in the double-effect absorption refrigerating machine having the above-described operation function, and a specific configuration example thereof will be described. 32 is a cold / hot water pipe 2.
2 is an input interface for inputting the temperature signals output from the temperature sensors 29 and 30 provided at the inlet / outlet of the evaporator 4, converting the signals and outputting them to the central processing unit (hereinafter referred to as CPU) 33, and 34 is a predetermined arithmetic program A storage device (hereinafter, referred to as a ROM) that stores such information, 35 is an output interface that inputs a signal from the CPU 33 and outputs a required control signal to the heating amount control valve 25, and 36 outputs a signal at predetermined time intervals. Signal generator (hereinafter referred to as CLOCK),
Reference numeral 37 denotes a readable / erasable storage device (hereinafter referred to as RAM) that stores the temperature detected by the temperature sensors 29 and 30.

In the ROM 34, the larger the difference between the predetermined temperature set in advance and the temperature of the cold / hot water detected by the temperature sensor 29, the larger the opening of the heating amount control valve 25 and the temperature sensor 29 detects. When the temperature of the cold / hot water reaches a predetermined temperature, a conventionally known capacity control program for closing the heating amount control valve 25 and stopping the combustion is stored.

The ROM 34 is connected to an appropriate member, for example, the control device 31 itself or the control device 31 via a signal line 51, and a remote control 40 installed in a building control room or the like turns on the absorption refrigerator. When the cooling / heating switch 41 provided together with the ON / OFF switch 40S and the like instructs the start of the cooling operation, the temperature T1 of the cold water detected by the temperature sensor 29 is detected every predetermined time.
1 is a predetermined set temperature, for example, 7 ° C. minus a first predetermined temperature, for example 1 ° C., and a second predetermined temperature A, for example, 1.5 ° C. is added to this, and calculation is performed. For example, a control program for opening the heating amount control valve 25 and starting the combustion of the gas burner 1B at the time of starting the cooling operation,

After the combustion of the gas burner 1B is started, the temperature T1 of the cold water detected by the temperature sensor 29 is detected every predetermined time, and the detected temperature T1 is from the predetermined set temperature 7 ° C. to the first predetermined temperature 1 When the temperature becomes 6 ° C. or lower, which is calculated by subtracting the temperature of 6 ° C., the heating amount control valve 25 is closed to stop the combustion, and the temperature T2 of the cold water detected by the temperature sensor 30 at this time is stored in the RAM 37. Control program,

Further, after the combustion of the gas burner 1B is stopped, the temperature T2 of the cold water detected by the temperature sensor 30 is detected every predetermined time, and the detected temperature T2 is the second value of the temperature T2 of the cold water stored in the RAM 37. Predetermined temperature A, for example 1.
When the temperature exceeds 5 ° C, the heating amount control valve 2
And a control program for resuming combustion of the gas burner 1B which opens 5 to restart combustion of the gas burner 1B.

Further, in the ROM 34, when the start of the heating operation is instructed by the cooling / heating switching switch 41 of the remote controller 40, the temperature T of the hot water detected by the temperature sensor 29.
1 is detected at predetermined time intervals, and the detected temperature T1 is set to a predetermined set temperature, for example, 45 ° C. to a first predetermined temperature, for example, 2.
5 ° C. is added and from this the second predetermined temperature B, eg 3.5
If the temperature is 44 ° C. or less, which is calculated by subtracting ℃, the heating amount control valve 25 is opened to start the combustion of the gas burner 1B.

After the combustion of the gas burner 1B is started, the temperature T1 of the hot water detected by the temperature sensor 29 is detected every predetermined time, and the detected temperature T1 is set to the predetermined set temperature 45 ° C. to the first predetermined temperature 2 Calculate by adding 5 ° C 4
When the temperature becomes 7.5 ° C. or higher, the heating amount control valve 25 is closed to stop the combustion, and the temperature T2 of the hot water detected by the temperature sensor 30 at this time is stored in the RAM 37.

Further, after the combustion of the gas burner 1B is stopped, the temperature T2 of the hot water detected by the temperature sensor 30 is detected every predetermined time, and the detected temperature T2 is the second from the temperature T2 of the hot water stored in the RAM 37. A control program for restarting combustion, in which the heating amount control valve 25 is opened to restart the combustion of the gas burner 1B when the temperature becomes equal to or lower than a predetermined temperature B, for example, 3.5 ° C., is stored.

Therefore, when, for example, the cooling operation is selected by operating the cooling / heating switching switch 41 of the remote controller 40, the control program for starting the cooling operation is activated, and the temperature sensor 29 detects that the outside air temperature is high. Temperature T
If 1 is 7.5 ° C. or higher, the heating amount control valve 25 is opened to start combustion of the gas burner 1B.

Then, the temperature T detected by the temperature sensor 29 is detected.
When the temperature T1 detected by the temperature sensor 29 becomes 6 ° C. or lower, the heating amount control valve 25 is closed to stop the combustion of the gas burner 1B. At the same time, the temperature T2 of the cold water detected by the temperature sensor 30 is stored in the RAM 37, and the temperature T2 of the cold water detected by the temperature sensor 30 is stored in the RAM 37 after the combustion of the gas burner 1B is stopped.
When the temperature exceeds the second predetermined temperature A, for example, 1.5 ° C., the heating amount control valve 25 is opened to open the gas burner 1
Restart B combustion.

As described above, the cooling water can be circulated and supplied to the cooling load (not shown) through the cold / hot water pipe 22 to perform the cooling operation, and the cooling operation is finished and the cooling water is returned to the evaporator 4. As for the temperature of the cold water to be cooled, the path from the outlet of the evaporator 4 to the temperature detecting portion of the cold water flowing back to the evaporator 4, that is, the temperature sensor 30, is long, and the amount of retained water during that time is sufficient to stop the combustion of the gas burner 1B. Since it is less affected by the capacity change due to the restart, and reflects the actual magnitude of the load, the frequency of combustion stop / restart of the gas burner 1B is reduced, the life of the device is extended, and the controllability is improved.

On the other hand, when the heating operation is selected by operating the cooling / heating switch 41 of the remote controller 40, the control program at the time of starting the heating operation is started, and the temperature T1 detected by the temperature sensor 29 is low because the outside air temperature is low. If it is 44 ° C. or lower, the heating amount control valve 25 is opened to start the combustion of the gas burner 1B.

Then, the temperature T detected by the temperature sensor 29
1 is controlled to a predetermined set temperature of 45 ° C., the capacity of the heating amount is controlled, and the temperature T1 detected by the temperature sensor 29 is 4
When the temperature becomes 7.5 ° C. or higher, the heating amount control valve 25 is closed to stop the combustion of the gas burner 1B, and the temperature T2 of the hot water detected by the temperature sensor 30 at this time is stored in the RAM 37.
After the combustion of the gas burner 1B is stopped, the temperature T2 of the hot water detected by the temperature sensor 30 is changed from the temperature T2 of the hot water previously stored in the RAM 37 to the second predetermined temperature B, for example, 3.5 ° C.
When the temperature becomes equal to or lower than the temperature obtained by subtracting, the heating amount control valve 25 is opened and the combustion of the gas burner 1B is restarted.

Therefore, also in this case, it is possible to circulate and supply hot water in a predetermined temperature range to a heating load (not shown) through the hot / cold water pipe 22 to perform the heating operation. The temperature of the hot water flowing back is determined by the temperature detecting portion of the hot water flowing back from the outlet of the evaporator 4 to the evaporator 4.
That is, the path to the temperature sensor 30 is long, and the amount of water held during that time is long enough to be less affected by the capacity change due to the combustion stop / restart of the gas burner 1B, which reflects the actual load. Combustion stop / restart frequency is reduced, the device life is extended, and controllability is improved.

Since the present invention is not limited to the above-described embodiments, various modifications can be made without departing from the spirit of the claims.

For example, in both cooling and heating, the first predetermined temperature may be set to 0 ° C. and the two-position control may be performed.

The set temperature during the cooling operation is, for example, in the range of 5.0 to 12.0 ° C. (steps can be set in 0.1 ° C. increments, the same applies below), and the first predetermined temperature is, for example, 0.5 to 2. 5
The temperature range of 2 ° C. and the second predetermined temperature can be set appropriately in the range of 1.0 to 9.0 ° C.,

The set temperature during heating operation is, for example, 4
The range of 0.0 to 60.0 ° C, the first predetermined temperature is, for example, 0.5 to 5.0 ° C, and the second predetermined temperature is, for example, 0.
It can be appropriately set in the range of 5 to 8.5 ° C.

Further, an antifreezing liquid such as ethylene glycol or calcium chloride solution may be used as the heat operation fluid flowing through the cold / hot water pipe 22.

[0038]

As described above, in the absorption chiller-heater of the present invention, the path from the outlet of the evaporator to the temperature detecting portion of the heat-operated fluid flowing back to the evaporator is long, and the heat stored in the path is long. The amount of operating fluid is sufficient so that it is unlikely to be affected by the capacity change due to on / off of combustion in the regenerator, and the restart of the combustion reflects the magnitude of the cooling / heating load and is returned to the evaporator. Since the operation is performed on the basis of the temperature of the operating fluid, not only the controllability is improved, but also the frequency of stopping / restarting the combustion is reduced to prolong the life of the apparatus.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example.

[Explanation of symbols]

 1 High Temperature Regenerator 1B Gas Burner 2 Low Temperature Regenerator 3 Condenser 4 Evaporator 5 Absorber 6 Low Temperature Heat Exchanger 7 High Temperature Heat Exchanger 8-11 Absorption Liquid Pipe 13 Absorption Liquid Pump 14-17 Refrigerant Piping 19 Refrigerant Pump 22 Cold / Hot Water Pipe 23 Cooling water pipe 24 Gas supply pipe 25 Heating amount control valve 26-28 Open / close valve 29 Temperature sensor 31 Control device 32 Input interface 33 CPU 34 ROM 35 Output interface 36 CLOCK 37 RAM 40 Remote control 40S ON / OFF switch 41 Cooling / heating Changeover switch 51 Signal line

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yuichi Suzuki 2-5-5 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd.

Claims (5)

[Claims] 1. A refrigerating cycle is constructed by connecting a regenerator, a condenser, an evaporator, an absorber, etc. with a pipe, and an endothermic action due to evaporation of a refrigerant liquid in the evaporator or a heat radiating action mainly due to condensation of a refrigerant vapor. In an absorption chiller / heater that cools or heats the required heat-operated fluid by circulating it to the required equipment, combustion in the regenerator based on the temperature of the heat-operated fluid discharged from the evaporator Is stopped, and the combustion in the regenerator is restarted based on the temperature of the heat-operated fluid that is returned to the evaporator. 2. The temperature of the heat-operated fluid that has returned to the evaporator by performing a cooling action is equal to the temperature of the heat-operated fluid that has recirculated to the evaporator when the previous combustion in the regenerator was stopped + the predetermined temperature. The method for controlling an absorption chiller-heater according to claim 1, wherein combustion in the regenerator is restarted when the above is reached. 3. The temperature of the heat-operated fluid that has returned to the evaporator by performing a heating action is the temperature of the heat-operated fluid that has recirculated to the evaporator when the previous combustion in the regenerator was stopped minus the predetermined temperature. The method for controlling an absorption chiller-heater according to claim 1, wherein combustion in the regenerator is restarted when the following occurs. 4. The combustion in the regenerator is started when the temperature of the heat-operated fluid that is cooled and is discharged from the evaporator is equal to or higher than the set temperature−the first predetermined temperature + the second predetermined temperature, and then the evaporation is performed. When the temperature of the thermally operated fluid discharged from the regenerator becomes equal to or lower than the set temperature-first predetermined temperature, the combustion in the regenerator is stopped, and the temperature of the thermally operated fluid recirculated to the evaporator is the regenerator. 2. The combustion in the regenerator is restarted when the temperature of the heat-operated fluid that has recirculated to the evaporator when the previous combustion was stopped at + the second predetermined temperature or more.
A method for controlling the absorption type chiller-heater described. 5. The heating in the regenerator is started when the temperature of the heat-operated fluid heated and discharged from the evaporator is equal to or lower than a set temperature + first predetermined temperature−second predetermined temperature, and then evaporation is performed. The combustion in the regenerator is stopped when the temperature of the thermally operated fluid discharged from the regenerator becomes equal to or higher than the set temperature + first predetermined temperature, and the temperature of the thermally operated fluid recirculated to the evaporator is the regenerator. 2. The combustion in the regenerator is restarted when the temperature falls below the second predetermined temperature of the temperature of the heat-operated fluid that has recirculated to the evaporator when the previous combustion was stopped in 1.
A method for controlling the absorption type chiller-heater described.