JPH03122461A - Control method of condensing pressure - Google Patents

Abstract

PURPOSE:To improve the reliability of a compressor and expand an available range of the outside temperature for saving energy by a method wherein the range of change in the condensing pressure is decreased by means of a combination of a fan group control method and a water spray control method of an air-cooled condenser. CONSTITUTION:Water spray is carried out on an air-cooled condenser 2 and the total number of fans 1 are opearted during normal operation. When the outside temperature falls below the set point, the operating number of the fans 1 is reduced to raise the condensing pressure. When the outside temperature falls further and the condensing pressure drops below the set point, water spray is stopped, and in addition, two or more or all the number of the fans are brought in operation to raise the condensing pressure. In the case the outside temperature drops while the water spray is stopped, causing the condensing temperature to drop below a set point, the operating number of fans 1 is reduced with water spray kept stopped, and the air flow rate is reduced for adjusting the condensing pressure. By this control, a sharp drop of the condensing pressure is restrained and the reliability of a compressor 4 is improved with saving energy.

Description

[Detailed Description of the Invention] [Industrial Application Field] A condensing pressure control system that combines a water sprinkling mechanism and a blower control system.

[Conventional technology]

The conventional device has a g! In air conditioners, the main purpose of water sprinkling is to lower the condensation pressure during high loads when the outside air temperature is high, and even in the case of air conditioners with multiple blowers, water sprinkling is performed when all the blowers are operating. It is being done.

In the above method, if the outside temperature drops from the water discharge state,
First, watering is stopped, and when the outside temperature drops further, the blower starts operating 117! The condensing pressure is adjusted by reducing the number.

[Problem to be solved by the invention]

Figure 8 shows the change in condensing pressure with respect to outside air temperature using both types of detailed blower control, Figure 4 shows the change in condensing pressure with respect to outside air temperature with the water spray control method, and Figure 6 shows the flow of condensing with four pressure controls in the conventional technology. , FIG. 7 shows the condensing pressure change with respect to FIG. 6.

As shown in FIGS. 8 and 4, in the blower pancreatic suppression system, the range of change in condensing pressure with respect to changes in outside air temperature is large, and in the case of the water sprinkling control system, the range of change in condensing pressure is small.

However, the operating range in which outside air can be used is small for both of the groan suppression methods.

In the conventional condensation pressure control system shown in FIG. 7, watering was started and stopped when the outside air temperature was high, so there was a large change in foundation and line pressure when watering was started and stopped.

In the case of a compressor that stores oil on the high-pressure side, such as a screw compressor, if the discharge pressure suddenly decreases, the refrigerant dissolved in the oil will foam, causing bubbles to form in the oil supplied to the bearings. Contamination may shorten the life of the compressor bearing.

In addition to the above-mentioned improvement in reliability, the high discharge pressure at a time of relatively high load immediately before the start of watering increases the input to the compressor, which is disadvantageous in terms of energy saving.

The purpose of the present invention is to compress +! The objective is to improve the reliability of KVC, expand the range of operation for outside flight A, and save energy.

[Means to solve the problem]

In order to achieve the above objective, we combined the blower #control method and the water discharge method, and when in the water condition, the condensation pressure change range with respect to the outside air @ degree is small, so if the outside air temperature drops below a certain set value, the outside air Thermostat reduces the number of blowers in operation! : Increases aphrodisiac pressure. In the case of water sprinkling or water sprinkling stopped from the collar, since the condensing pressure changes widely due to changes in outside air temperature, if the outside air temperature drops and the condensing pressure falls below a certain set value, the pressure switch will stop watering. At the same time, a plurality of blowers or all blowers are operated to increase the condensing pressure.

Setting 1: When watering is stopped, the outside temperature drops and there is condensation pressure.
Even when the air pressure drops to below normal, the number of blowers in operation is reduced by reducing the pressure.

[Effect]

During excessive operation, water is sprinkled on the air-cooled condenser and all blowers are operated, and when the outside air temperature drops below a certain set value, the outside air thermostat is activated to reduce the number of blowers in operation and increase the condensing pressure. Furthermore, when the outside air temperature drops and the condensing pressure drops below a certain set value,
The pressure switch is activated to stop the water discharge and to operate multiple or all blowers to increase condensation and line pressure. If the outside air temperature drops and the condensation pressure drops below a certain set value when watering is stopped, a pressure switch is activated to reduce the number of operating blowers and suppress the amount of air blown while watering remains stopped.
(Difference 7 compression pressure by A.

The above +ft1J noise suppresses a sudden drop in condensing pressure, improves the reliability of the compressor, and makes it possible to save energy.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Figure 1 is a 1S diagram of 11 O air conditioners according to the present invention, in which 1 is the blower, 2 is the air-cooled condenser, 8 is the water sprinkler mechanism, scratches are the compressor, 5 is the evaporator, and 6 indicates an expansion valve. Figure 2 shows the original F! A7) This is a diagram showing the air conditioner control circuit. In the diagram, 7 is the outside air thermostat (3 rows).
B, OFi at 5'C? , ON at 35°C), 8 is a pressure switch (OFF at 15kIj/12G as an example,
ON at 101q/cs2G), 9 is pressure force switch (for example, oFF at 13 kg/cm2G, 18 kg/cs
10 is the first blower motor 11 is the second blower motor, 12 is the water sprinkling command relay.

Fig. 8 shows the change in condensing pressure in the vertical direction and the change in outside air temperature in addition to that, and shows the change in condensing pressure with respect to the change in outside air temperature using the conventional blower system. No. 41A shows the change in condensing pressure with respect to the change in outside air temperature due to the conventional 7) water sprinkling control method. FIG. 5 shows the change in condensing pressure with respect to the change in outside air temperature according to the present invention. 13 and 14 in the diagram
15 and 16 are in a water collecting state, 13 and 15 are in bad operating condition with one IL blower, and 10 is in operating condition with two blowers. FIG. 6 shows a prior art pseudo condensation pressure control flow, and FIG. 7 shows changes in condensing pressure with respect to changes in outside air temperature with respect to FIG.

41 to 7 are diagrams assuming that the number of blowers is two.

During normal operation, the blower motors 10 and 1 are
1. The water sprinkling command relay 12 is turned on, the two blowers 1 shown in FIG. This lowers the condensing pressure and reduces the input to the IE condensation tank.

As shown in FIG. 5, when the outside air temperature decreases, the condensing pressure also decreases due to the demand for condensing capacity. At this time, if the condensing pressure is extremely reduced, the pressure difference before and after the expansion valve becomes too small, so that sufficient t of refrigerant liquid is not supplied, resulting in an inefficient refrigeration cycle. Therefore, when the outside air temperature drops during watering, the outside air thermostat reduces the number of operating blowers to increase the condensing pressure (FIG. 5, 16->15).

In this case, the outside air thermostat is used to increase the condensing pressure. As shown in FIG. 4, the inclination of the condensing pressure change with respect to the outside air temperature is small during watering.

If the outside 'A temperature further decreases and the condensing pressure falls below the set value (for example, l 3 <ti/ls G ),
When the pressure switch 9 energizes the blower motor 11, the D watering from the watering mechanism 3 is stopped, and the two blowers 1 are operated to increase the condensing pressure (Fig. 5, 15-14). When watering is stopped and the outside temperature is low, the condensing pressure is lower than the set value (l Okg/l).
s G ), the pressure switch 8 is in the OFF state 1
By reducing the number of blowers in operation and suppressing the amount of air flow, #! Increase the compression pressure (Fig. 5 14→13).

D, which uses a pressure cassette, has a large slope of condensation A and power saving change J'') relative to the outside air temperature when watering is stopped, as shown in Figures 3 and 4, so it depends on the pressure.
This is because +H is more effective.

As described above, according to the embodiment of the present invention, by combining the blower # control method and the water spray rflIJ 1lt11 method, the change in condensing pressure is reduced, thereby suppressing rapid changes in condensing pressure and improving the reliability of the compressor. This not only improves performance but also expands the usable range with respect to outside temperatures.

In addition, by sprinkling water during normal operation, it is possible to reduce the input to the compressor and save energy.

〔Effect of the invention〕

According to the invention, plural +t! 7) Air-cooled condenser with a blower, air-cooled condenser, and embroidery device/) In an air conditioner with a water sprinkling mechanism, water is sprinkled during regular operation, and when the outside temperature drops, the number of blowers in operation is reduced, and when the outside temperature drops, By stopping water sprinkling when the pressure drops, the condensing pressure is stabilized regardless of changes in outside temperature, making it possible to improve the efficiency of the compressor and save energy.

[Brief explanation of drawings]

FIG. 1 is a structural diagram of an air conditioner according to an embodiment of the present invention (7).
Figure 2 shows the first air conditioner stop machine n-IJ (to) circuit D.
It is a circuit diagram showing a part. FIG. 8 is a diagram showing the condensing pressure cuff 0- by the conventional blower group control method, FIG. 4 is a diagram showing the condensing pressure cuff flow by the conventional one-way water spray control method,
FIG. 5 is a diagram showing the condensing pressure cuff flow according to the embodiment of the present invention, and FIG. 6 is a diagram showing the condensing pressure 1. IfIII
FIG. 7 is a diagram showing the condensing pressure flow according to the prior art. 1...Blower 2...Upper cooling compressor 8...Water sprinkler 4...Compressor 5...Evaporator 6...Expansion valve 7...Outside air thermostat 8...Pressure switch 9...Pressure changeover switch lυ...1st
Blower motor 11...Second blower motor 12
...Water discharge command relay 18...When one blower is operating with watering stopped 14...When two blowers are operating with watering stopped 15...When one blower is operating with watering stopped 16. ...When operating two blowers in icy conditions. 1 straw, 2 i! Direct insult. 4 Pressure t~ Machine 7 Kuta (→Namoszu・!<← 10 Ya 1j (11 I Kan7-ta Z Of course, Nikkan 5S, Sapphichi δ Stone Lf) Suzu・Iihi 11 Naka Z selfh -1 shift 3rd.ε-fu 3 temple i cyano ni 8' 6 Qincho rod q hh+77 glaze I...洟2 pane 7 finger/+cho L- shave 41 yen 1 6th m

Claims (1)

[Claims] 1. In an air conditioner having an air-cooled condenser having a plurality of blowers and a water sprinkling mechanism for the air-cooled condenser, normally,
All of the blowers are operated and water is sprinkled on the air-cooled condenser, and when the outside temperature drops, the number of blowers in operation is first reduced, and then when the outside temperature drops, the water sprinkling is stopped and the number of blowers in operation is increased to multiple or all units. Then, again,
A condensing pressure control method characterized by reducing the number of operating blowers while watering is stopped when the outside temperature further drops after watering is stopped. 2. In the product according to claim 1, when watering, the change in condensation pressure in response to a change in outside air temperature is controlled by adjusting the number of operating blowers using an outside air thermostat, and when watering is stopped, the change in condensation pressure in response to outside temperature is controlled by a pressure switch. A condensing pressure control method characterized in that the condensing pressure is controlled by adjusting the number of operating blowers.