JPS62106241A - Air-conditioning device - Google Patents

Abstract

PURPOSE:To control the outlet water temperature of an utilizing side heat exchanger within a predetermined temperature range and prevent freezing in the heat exchanger by a method wherein a compressor operating and stopping means, operating or stopping a compressor on an operating signal or a stopping signal generated from an operating stopping compressor selecting means, is provided in the title device. CONSTITUTION:When a temperature detecting signal, generated from a temperature detector 10, has arrived at a signal level corresponding to a preset temperature, an operating or stopping compressor selecting means 15 selects a compressor 2a or the compressor 2b to be stopped on the basis of an output signal generated from a compressor stopping water temperature judging means 11, and a selected compressor operating and stopping means 3a for A series or the same means 13b for B series stops the operation of the compressor. On the other hand, when the output signal generated from the compressor stopping water temperature judging means 11 is supplied, the temperature detecting signal generated from the temperature detector 9 is memorized. When a signal level difference between the temperature detecting signal and the other temperature detecting signal, generated from the temperature detector 9 later, has arrived at the signal level difference corresponding to a preset temperature difference, the compressor 2a or the same 2b which is to be operated is selected by the operating and stopping compressor selecting means 15 on an output signal generated from an inlet water temperature changing amount judging means 14, whereby the compressor operating and stopping means 13a or the same means 13b starts said compressor.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention enables the operation of an air conditioner having a plurality of compressors without any problem even if the capacity of the air conditioner and the flow rate of circulating water for air conditioning change. , relates to an air conditioner capable of capacity-controlling the temperature of the circulating water within a predetermined temperature range.

[Conventional technology]

Conventionally, as a method for controlling the temperature and capacity of circulating water for air conditioning in an air conditioner having a plurality of compressors, a method using the inlet water temperature of a heat exchanger on the user side has generally been used.

In Fig. 6, (1) indicates two mutually independent compressors (2a), (2b), an unused side heat exchanger (aa), (
8b) An air conditioner having a mutually independent refrigeration cycle ^3 composed of a throttle device (4a), (4b) and a user-side heat exchanger (5a), (5b),
Air is taken into the non-use side heat exchangers (8a), (21b) by blowers (50a), (50b).

In addition, an inflow pipe (6) and an outflow pipe (7) for inflowing and outflowing circulating water for air conditioning are connected in parallel to the heat exchangers (5a) and (5b) on the user side. Side heat exchanger (5a).

Circulating water for air conditioning is taken in (5b). (8) is a second temperature detection device for capacity control, which is provided with a temperature sensing section (8a) in the multi-stage flow section of the inflow pipe (6). In the figure, solid line arrows indicate the flow direction of the refrigerant, and dashed line arrows indicate the flow direction of the air conditioning circulating water.

One function of the air conditioner (1) having such a configuration will be explained. The high pressure gas refrigerant discharged from the compressors (2a) and (2b) is transferred to the non-use side heat exchangers (la) and (8b).
The air is guided by the blowers (50a) and (50b) and condensed by radiating heat to the air, which is then drawn into the expansion devices (4a) and (4).
The pressure is reduced in b), and the user side heat exchanger (5a), (5b)
At the same time, the heat exchanger on the user side (5a),
It constitutes a well-known refrigeration cycle in which air-conditioning circulating water (hereinafter referred to as cold water) flowing through (5b) is cooled and returned to the compressors (2a) and (2b). In addition, the cold water inlet (6
) and the outlet (7) are connected to a cold water circulation pump and an indoor fan coil unit through water piping (not shown), and the user side heat exchangers (5a), (5b)
The room is cooled by the cold water supplied by the system. In addition, the temperature detection device (8), which is provided with a temperature sensing part (8a) in the cold water inflow pipe (6), detects the temperature of the compressor (2a) according to the cold water inlet temperature, that is, the temperature of the cold water after passing through the indoor fan coil unit.
This is a one-time system that controls the start and stop of (2b) and constantly supplies cold water commensurate with the load. FIG. 6 shows the operating temperature characteristics of the temperature detection bag @ (8) and the operating state of the air conditioner (1). It is a step type thermostat. In other words, the set temperature, for example, the high temperature side cutting wetness, is 10
,5℃, high temperature 13.5℃, low temperature 9℃
, the low-temperature temperature is 12°C, and the compressor (2a) is operated by the high-temperature side contact.

The compressor (2b) is controlled to start and stop by the low-temperature side contact. Therefore, when the cooling load on the indoor fan coil unit side decreases, the chilled water inlet temperature decreases because the amount of heat extracted from the room decreases. However, when the temperature reaches the high-temperature side cutting temperature of 10.5°C, the operation of the compressor (2a) is stopped, and the cooling load is compensated for by the operation of only the compressor (2b). When the temperature decreases, the cold water inlet temperature further decreases, and when the low temperature side cut temperature reaches 9℃, the operation of the compressor (2b) also stops, and the operation of the air conditioning bag @ (1) is completely shut down. The system will stop and wait for the cooling load to increase.When the cooling load increases thereafter, the temperature detection device (8
) The cold water inlet temperature at the cold water inlet (6), which is provided with a temperature sensing part, rises, and the temperature reaches a temperature of 12℃ -
When this is achieved, the compressor (2b) is activated and begins to cool the circulating water for air conditioning.

Furthermore, as the cooling load increases, the cold water inlet temperature rises.

When the cold water inlet temperature reaches the high temperature of 18.5℃E, the compressor (2a) also starts, and the air conditioner (1) reaches 100℃.
% load (operate with a trowel.

In order to simplify the explanation, the above description is based on the case where the cooling load changes in one direction, either decreasing or increasing.
), (2b) are of course controlled by the temperature detection device (8).

[Problem that the invention seeks to solve]

As mentioned above, in conventional air conditioners, the operation of the compressor is controlled by the capacity of the inlet water temperature of the heat exchanger on the user side, so even if the capacity of the air conditioner changes, the inlet water temperature remains constant. Even if the outlet water temperature fluctuates, the range of variation in the outlet water temperature becomes large. In addition, the flow rate of circulating water for air conditioning also fluctuates due to changes in the flow rate of circulating water, and if the flow rate of circulating water decreases due to a decrease in pump capacity or clogged pipes, the outlet water temperature will drop more than necessary, and in the worst case Furthermore, there were problems such as the risk of water freezing inside the heat exchanger on the user side. Further, the temperature at which the first high-temperature side compressor (2a), whose capacity is controlled by the inlet water temperature, stops needs to be set higher than the low-temperature side cut-off temperature. In order to prevent water from freezing, the low-temperature side cut temperature is usually set at a temperature difference of 5 degrees at the entrance and exit of the heat exchanger on the user side.
Considering the above, the outlet water temperature where there is a possibility of water freezing is 4℃ + 5
A temperature of 9 degrees Celsius or higher is defined as a low temperature side cutting temperature. Therefore, the minimum temperature for the high temperature side compressor is usually around 10.5℃, for example, even if you want to set the outlet water temperature to 5℃, the temperature is 10.5-5 deg.
．． 5 degrees Celsius does not correspond to 5 degrees Celsius, and the temperature is usually higher because a child beam is taken.

This invention was made to solve the above-mentioned problems, and even if the capacity of the air conditioner or the flow rate of circulating water for air conditioning changes, the water can be compressed within a constant water temperature range according to the circulating water flow rate. The purpose is to obtain an air conditioner that can control the capacity of the machine and control the water temperature.

[Means for Solving Problems] Invention 1 This air conditioner includes a refrigerant compressor that takes in refrigerant, compresses it and discharges it, and a refrigerant supplied from this compressor and a fluid to be heat exchanged. A non-use side heat exchanger, a use side heat exchanger that exchanges heat between the refrigerant supplied from the compressor and air conditioning circulating water that is circulated to an air conditioning load device such as a fan coil unit, and this use side heat exchanger. A first temperature detector detects the outlet water temperature of the heat exchanger and generates an output signal corresponding to the outlet water temperature; a second temperature sensor that generates an output signal; and a compressor that generates an output signal when the temperature detection signal generated from the first temperature sensor reaches a signal level corresponding to a preset temperature. a stop water temperature determining means, an inlet water temperature storing means for storing a temperature detection signal generated from the second temperature detector when the output signal generated from the compressor stop water temperature determining means is supplied; When the signal level difference between the temperature detection signal generated from the temperature detector and the temperature detection signal stored in the inlet water temperature storage means reaches a signal level difference corresponding to a preset temperature difference, an output signal is generated. Based on the output signal generated from the inlet water temperature change amount determining means, the compressor stop water temperature determining means, and the output signal generated from the inlet water temperature change amount determining means, An operation stop compressor selection means for selecting a compressor to be operated or stopped from among the compressors and generating an operation or stop signal for the selected compressor; and an operation or stop signal generated from the operation stop compressor selection means. The above object is achieved by configuring the above air conditioner by providing a plurality of compressor operation/stop means for operating or stopping the compressor (1).

(Operation) In the present invention, when the temperature detection signal generated from the first temperature sensor reaches a signal level corresponding to a preset temperature, the temperature detection signal generated from the first temperature detector is based on the output signal generated from the compressor stop water temperature determining means. The operation stop compressor selection means selects the compressor to be stopped, and the selected compressor operation stop means stops the operation of the compressor.Meanwhile, an output signal generated from the compressor stop water temperature determination means is supplied. , the temperature detection signal generated from the second temperature sensor at that time is stored, and this stored temperature detection signal and the second
When the signal level difference with the temperature detection signal generated from the temperature sensor reaches a signal level difference corresponding to a preset temperature difference, the operation is started based on the output signal generated from the inlet water temperature change amount determining means. The compressor to be operated is selected by the stop compressor selection means, and the compressor operation stop means operates to start the compressor.

[Embodiment] FIG. 1 is an overall configuration diagram of an air conditioner showing an embodiment of the present invention. The refrigeration cycle side of this embodiment is the same as that of the conventional embodiment, but as is clear from the figure, the control section is configured as follows. (9) is a second temperature detection device installed in the inlet pipe (6) of the user-side heat exchanger (5a), (5b) to detect the inlet water temperature and generate an output signal according to this inlet water temperature. α1 is installed in the outflow pipes (7) of the user-side heat exchangers (5a) and (5b), and detects the outlet water temperature, and generates the output power according to this outlet water temperature. Temperature detector 1, αυ, is a compressor stop water temperature determination means, and when the temperature detection signal generated from the first temperature detector αQ reaches a signal level corresponding to a preset temperature, an output signal is generated. is generated. In (2), the output signal generated from the compressor stop water temperature determining means is supplied, and at this time the second temperature detector (
9), α4 is a temperature detection signal generated from the second temperature detector (9) and the temperature detection signal stored in the inlet water temperature storage means @; signal level difference.

The inlet water temperature change amount determination means generates an output signal when a signal level difference corresponding to a preset temperature difference f is reached. (laa) and (18b) are based on the output signal generated from the compressor stop water temperature determination means east.
Based on the output signal generated from the first inlet water temperature change amount determination means α4 while stopping the steps a) and (2b).

This is a compressor operation stop means for starting the compressors (2a) and (2b). C1G is the compressor (2a) based on the output signal generated from the compressor stop water temperature determining means.

(2b) If both are in operation, set the refrigeration cycle of A to the pressure g
i (2b) If only one unit is in operation, select the B refrigeration cycle and output the output signal of the compressor stop water temperature determination means aU of each compressor 6 operation/stop means (compressor stop water temperature determination means aU), and check the above-mentioned inlet water temperature change. Based on the output signal generated from the quantity determining means σ4, if both compressors (2a) and (2b) are stopped, the refrigeration cycle of B is started, and if only one compressor (2a) is stopped, the refrigeration cycle of A is started. The operating/stopping compressor selecting means selects a cycle and outputs an output signal of the inlet water temperature change amount determining means to each compressor operating/stopping means.

FIG. 2 is a circuit diagram showing the electrical connections of the air conditioner shown in FIG. 1. In the figure, a microcomputer in the control device αη includes a CPU 01 , a memory (1), an input circuit (2), and an output circuit (material). Zeng (to)
is each temperature sensor (9), a resistor in series with QO, CIB
is an A/D converter to which the detection outputs of each temperature detector (9) and αQ are inputted and converted into digital data, and the output thereof is given to the same input circuit. The effect is a resistor in series with the operation switch.

(2) is a resistor connected in series with the protection device (2) of the compressors (2a) and (2b), and the state signal of the operation switch (4) and the protection device (7) is also applied to the input circuit (4). Compressor operation/stop means (18a)-(18b) includes auxiliary relays (ala), (81b) and contacts ( 81a-a)
.

(81b-a) and terminal (82a), (a2b)
The transistors (88a) and (88b) have resistors (
It is connected to the output circuit (a) via 84a) and (84b).

Next, the operation of the above embodiment will be explained with reference to FIGS. 3 and 4. FIG. 8 is a flowchart showing the air conditioner program stored in the memory (e) of the microcomputer (g), and FIG. 4 is an operating characteristic diagram of the Koyokoro air conditioner according to the present invention.

First, when the operation switch 4 is closed, the ON signal is input to the input circuit -, step (7) shown in Fig. 8 is executed, and then step 2 starts to determine whether the water temperature is at a temperature that allows operation to start. . This determination is made by a control separate from the control means shown in FIG.
This is only done when the engine is closed and the engine is started.
compressor (2a) by the first temperature detector QO detecting the outlet water temperature.

If the temperature at which (2b) is to be stopped is set to, for example, 8°C, the inlet water temperature is further increased to, for example, 8°C with respect to this set temperature.
If the value is higher than that, a determination of r YES J is made. The temperature of the air-conditioning circulating water detected in this judgment uses the inlet water temperature of the user-side heat exchanger (5), and the second temperature detector (
9), is digitized by an A/D converter), and is input to an input circuit.

Next, based on the result of the determination, if the determination is r No J, the determination is performed again and the determination is repeated until the 5 determination becomes rYESJ. r If YES J, proceed to step (to) and output from the output circuit, turn on transistors (88a) and (88b), and turn on the auxiliary relay (l).
la).

(81b) is excited and contacts (81a-a), (81
b-a) is closed.

A signal is output from the terminals (82a) and (82b) to the compressor electromagnetic switches (not shown) of each system A and B, and the compressor (
The blowers (50a) and (50b) start operating in conjunction with 2a) and (2b) and the compressors (2a) and (2b),
As shown at point rAJ in FIG. 4, the outlet water temperature begins to decrease.

Next, in step (to), the compressors (2a) and (2b)
jc It is determined whether there is any abnormality or not, and if it is determined that there is an abnormality, the process proceeds to step), where the output from the output circuit disappears and the auxiliary relay (lla), (81
b) is deenergized, compressors (2a), (2b) and blower (50a).

(50b) stops. The presence or absence of an abnormality is determined by inputting the signal from the abnormality detector (1) to the same input circuit and using the CPUq value. Next, in step 葡～(Foundation), compressor stop water temperature determination operation and inlet water temperature storage operation are performed.
, it is determined whether the detected outlet water temperature To and the set water temperature Ts satisfy To≦Ts, and To≦Ts.
If not, proceed to step (goods) and step (6
) (trans) tin is not executed. The area between point A and point B in Fig. 4 is the area of To>T8, and during this period the compressor (2a),
(2b) continues to operate and lowers the temperature of the air conditioning circulating water.

After a certain time, if To≦Tsl, step (
In step 6), it is determined whether or not the compressor of system A is in operation, and if it is in operation (both systems A and 8 are in operation), the process advances to step (42-a). Output circuit @A side 0] Output is lost, and the compressor (2a) and blower (50a) stop. Immediately after the A system compressor (2a) is stopped, the inlet water temperature Ti1a is stored in the memory (2) on the microcomputer side. Point B in Figure 4 is the point where the A system compressor (2a) has stopped, and the outlet water temperature is 8.
℃ and stopped due to this. Next, in step (b) μs, in order to perform the water temperature determination performed in step (b) only in the refrigeration cycle when the compressor is stopped, the compressors (2a) and (2b) are either running or stopped. In step (goods), the B system is determined, and the process advances to step (t) where the B system compressor (2b) is in operation, where the A system is determined, Since it is stopped, the process advances to step (46a). Here, the inlet water temperature Ti2 is compared with the stored inlet water temperature Ti1a when the A system compressor is stopped. If it rises more than 'C, Ti2>
Ti1a+2, and it is determined that the compressor (2a) is in operation. But 1. When the air conditioning load of a load device such as a fan coil unit is small, the refrigeration cycle of the B system continues to operate, and the chilled water temperature continues to decrease Ti2 > T
i la + 2 does not hold and becomes rNOJ, which returns to step (to) and executes r YES If ≦Ts is established, the process proceeds to step S1 where it is determined whether the A system compressor is in operation.

In this case, the compressor (2a) of system A has already stopped.
The result is "NO", and the process proceeds to step (42b), where the output from the B system side disappears from the output circuit □□□, and compression @ (2b
) and the blower (50b) are stopped. Immediately after that, the inlet water temperature Ti1b is stored in the memory (2) of the microcomputer (g). Point C in FIG. 4 is point f when the compressor (2b) of system B stops. Next, the process proceeds to step (b), and the compressor (2b) of the B system is stopped and becomes NOJ, and the process proceeds to step (46b). After the compressor (2b) is stopped in step (46b), the temperature L of the cold water increases;
The water temperature gradually rises toward the point, and is stored as inlet water temperature Ti2. t: The artificial water temperature Ti1b when the B system compressor is stopped is compared, and the inlet water temperature Ti2 is stored. f: Inlet water temperature Ti1
For example, 2de is the pre-set temperature difference between b and f.
If the temperature rises from g℃ to 1, then Ti2>Filb+2 and f
(S fE compressor operation is determined and the process proceeds to Step 5, step (47b). The B system compressor (2b) and blower (50b) are operated, and the B system refrigeration cycle is activated to lower the chilled water temperature. Next, go back to step (to) again and determine if the protective device has been activated, and if not, go to step I.
Proceed to. In step c-, the detected outlet water temperature T
It is determined whether or not o and the set water temperature Ts satisfy TO≦Ts. In this case, for example, the air load increases and B
If the chilled water temperature does not decrease in the system refrigeration cycle alone, but increases instead, To≦Ts does not hold and r No
J, proceed to step ■, and check the B system compressor (2b month).
2a) is stopped and advances to step (46a,), step (46a)! Here, the temperature of the cold water rises 17 The artificial water temperature Ti2 is compared with the stored artificial water temperature Tima when the A system pressure hl is stopped, and the inlet water qTi2 is found to be
Preset the temperature difference between 1 and 2 degrees, for example, 2 degrees.
℃ rises by 1 nihi; if nf"i2>Ti1a+2, it is determined that the pressure a is in operation, and step (47a) 舊ζ, rA
System pressure-ii GA (, 2a), %, 7 feed J
[Xl (5s a) is operated, and thereafter the operation and stop of each refrigeration cycle are repeated according to the above flowchart. Point E in FIG. 4 is the point at which the compressor (to) starts operating again.

In addition, although the above embodiment describes the case of an air-cooled cooling-only air conditioner, the same applies to a water-cooled type.
Further, in a heat pump type air conditioner as well, the same effects as in the above embodiment can be obtained by reversing the set water temperature and the direction of water temperature change during heating as well as during cooling.

〔Effect of the invention〕

As described above, according to the present invention, there is provided a refrigerant compressor that takes in, compresses and discharges refrigerant, a non-use side heat exchanger that exchanges heat between the refrigerant supplied from the compressor and the fluid to be heat exchanged; A plurality of mutually independent refrigeration cycles each consisting of a user-side heat exchanger that exchanges heat between refrigerant supplied from a compressor and air-conditioning circulating water that is circulated between an air-conditioning load device such as a fan coil unit; a first temperature detector that detects the outlet water temperature of the heat exchanger and generates an output signal according to the outlet water temperature; a second temperature sensor that generates an output signal in response to the above, and generates an output signal when the temperature detection signal generated from the first temperature sensor reaches a signal level corresponding to a preset temperature; an inlet water temperature storage means for storing a temperature detection signal generated from the second temperature detector when the output signal generated from the compressor stop water temperature determination means is supplied; When the signal level difference between the temperature detection signal generated from the second temperature detector and the temperature detection signal stored in the inlet water temperature storage means reaches a signal level difference corresponding to a preset temperature difference of 1, Based on the inlet water temperature change determination means for generating an output signal, the output signal generated from the compressor stop water temperature determination means, and the output signal 1 generated from the inlet water temperature change determination means, An operation stop compressor selection means for selecting a compressor to be operated or stopped from among the compressors and generating an operation or stop signal for the selected compressor; and an operation or stop signal generated from the operation stop compressor selection means. Due to the provision of a means to stop the compressor operation,
Since the air conditioner is configured, 1. For example, even if the flow rate of the air conditioning circulating water is changed due to a decrease in the capacity of the circulation pump or a blockage in the piping, etc.

The outlet water temperature of the user-side heat exchanger could be capacity-controlled within a predetermined temperature range, and the fear of freezing inside the user-side heat exchanger could be eliminated. Furthermore, even when the capacity of the air conditioner changes, it is possible to solve the problem of the outlet water temperature fluctuating significantly or being unable to obtain a low outlet water temperature, which is the case with conventional devices.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an air conditioner showing an embodiment of the present invention, FIG. 2 is a circuit diagram showing electrical connections of the air conditioner shown in FIG. 1, and FIG. 8 is a flow chart showing its operation. Fig. 4 is an operating characteristic diagram of the air conditioner shown in Fig. 1, Fig. 5 is a configuration diagram of a conventional air conditioner, and Fig. 6 is an operating characteristic diagram of the air conditioner shown in Fig. 5. . In the figure, (2a) (2b) are compressors, (8, a) (
8b) is the heat exchanger on the non-use side, (5a) and (5b) are the heat exchangers on the use side, (9) is the temperature detector of 12, αQ is the first temperature detector, and the tool is the compressor stop water temperature determination The means and a3 are inlet water temperature storage means. (18a) and (18b) are compressor operation/stop means, Q4
1 is an inlet water temperature change amount determination means, and (A) is an operation/stop compressor selection means. r (The same reference numerals in each figure indicate corresponding parts.

Claims (1)

[Claims] A refrigerant compressor that sucks in refrigerant and compresses and discharges it, a non-use side heat exchanger that exchanges heat between the refrigerant supplied from this compressor and a fluid to be heat exchanged, and a fan coil unit that connects the refrigerant supplied from the compressor with a fan coil unit, etc. A plurality of mutually independent refrigeration cycles each consisting of a user-side heat exchanger that exchanges heat with the air-conditioning circulating water that is circulated to the air-conditioning load equipment, detects the outlet temperature of the air-conditioning circulating water of the user-side heat exchanger, and a first temperature detector that generates an output signal according to the temperature; a second temperature detector that detects the temperature of the air-conditioning circulating water inlet of the user-side heat exchanger and generates an output signal according to the inlet water temperature; vessel, above 1st
compressor stop water temperature determining means for generating an output signal when the temperature detection signal generated from the temperature detector reaches a signal level corresponding to a preset temperature; an output signal generated from the compressor stop water temperature determining means; is supplied, an inlet water temperature storage means for storing a temperature detection signal generated from the second temperature detector, and a temperature detection signal generated from the second temperature sensor and recorded in the inlet water temperature storage means. Generated from the inlet water temperature change amount determination means and the compressor stop water temperature determination means that generate an output signal when the signal level difference with the temperature detection signal reaches a signal level difference corresponding to a preset temperature difference. Selecting a compressor to operate or stop from among the plurality of compressors based on the output signal generated from the inlet water temperature change amount determination means and the output signal generated from the inlet water temperature change amount determining means, and generating an operation or stop signal for the selected compressor. An air conditioner comprising a compressor to be stopped selection means and a compressor operation stop means for operating or stopping the compressor based on an operation or stop signal generated from the operation or stop compressor selection means.