JPS637290B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method of controlling a water chiller/heater having a plurality of water chillers/heaters arranged in parallel.

In this specification, a cold/hot water machine refers to a refrigerator, a cold water machine, a hot water machine, or a cold/hot water machine. Cold and hot water refers to cold water or hot water.

[Conventional technology]

If multiple water coolers and hot water machines with different characteristics are installed, depending on the operating conditions, one of the water coolers and hot water machines should be operated primarily, and the other water coolers and hot water machines should be operated with as light a load as possible. may be desired. For example, if one is an electric centrifugal chiller and the other is a gas-cooled/heated water machine, if the energy supply conditions change, it is preferable to mainly use the more advantageous one.

[Problem that the invention seeks to solve]

However, for example, when two cold/hot water machines are installed in parallel like this, and only the cold/hot water outlet temperature controller is installed in each cold/hot water machine, the temperature setting values of these two controllers If they are the same, both No. 1 and No. 2 water coolers can only be controlled at the same load factor, and if the temperature settings of the two controllers are different, the temperature of the cold and hot water after merging will be different. It is unclear whether it has changed.

Except for the above-mentioned drawbacks of the conventional method of the present invention, a cold/hot water system that can select an advantageous one among a plurality of cold/hot water machines and mainly operate it, and stably obtain a predetermined confluence temperature. The purpose of this invention is to provide a control method for the following.

[Means for solving problems]

The present invention provides a method for controlling a hot and cold water device in which a plurality of cold and hot water machines that produce cold and hot water are arranged in parallel, and the cold and hot water from each of the cold and hot water machines is combined and supplied to a cold and hot water load. A certain number of cold/hot water machines in the first group individually control their capacity so that the cold/hot water outlet temperature of the cold/hot water machines reaches a predetermined individual setting temperature, and the cold/hot water machines in the second group of other machines control their respective capacities independently. The water machine performs capacity control so that the combined cold and hot water supplied to the cold and hot water load reaches a predetermined combined water set temperature according to the size of the cold and hot water load, and adjusts the individual set temperature to the combined water set temperature. A method for controlling a cold/hot water device, which is characterized by setting as follows.

Note A When mainly operating the 1st group (i) When producing cold water Individual set temperature < Combined water set temperature (ii) When producing hot water Individual set temperature > Combined water set temperature B When mainly operating the 2nd group (i) When producing cold water: Individual set temperature > Combined water set temperature (ii) When producing hot water: Individual set temperature < Combined water set temperature.

〔Example〕

Embodiments of the present invention will be described using the drawings.

In Fig. 1, 1 is a cold water inlet, 2 is a return header, 3 and 4 are pumps, and 5 is a first cold water machine.
Refrigerator, 6 is a second refrigerator as a cold/hot water machine, 7.
8 is a cold water outlet, 9 is an outgoing header, and 10 is a cold water merging outlet. 11 and 12 are energy supply valves, 1
3, 14, and 15 are temperature regulators, and 16, 17 are changeover switches.

The first refrigerator 5 and the second refrigerator 6 are each capable of independently controlling the capacity by a temperature controller 13 provided at the cold water outlet 7 or a temperature controller 14 provided at the cold water outlet 8. , the capacity can also be controlled by the temperature regulator 15 provided at the cold water confluence outlet 10 using the changeover switches 16 and 17.

Now, assuming that the first refrigerator 5 is more advantageous than the second refrigerator 6 in terms of energy, the first refrigerator 5 is mainly operated to produce cold water. In this case, the capacity of the first refrigerator 5 is independently controlled by the temperature regulator 13 based on the temperature of the cold water outlet 7 by the changeover switches 16 and 17, and the capacity of the second refrigerator 6 is controlled according to the size of the cold water load. The capacity is controlled by the temperature controller 15 based on the temperature of the cold water confluence outlet 10 so that the combined cold water supplied to the cold water load has a predetermined combined water set temperature. For example, if you want the cold water temperature of the combined water to be 7°C, set the combined water temperature of the temperature controller 15 to 7°C.
℃, and the individual setting temperature of the temperature controller 13 is set lower than 7℃.

In this case, the second refrigerator 6 is controlled by the temperature regulator 15, but since the first refrigerator 5 is operated at an average load or higher, the second refrigerator 6 is operated with a light load. Since the temperature of the cold water supplied to the load is controlled by the temperature controller 15, a predetermined temperature can be stably obtained.

Note that during operation, the chilled water load is reduced and the second refrigerator 6
may stop. In that case, it would be better to stop the pumps as well to save energy. However, regardless of the stoppage of these pumps, the temperature regulator 15
If the second refrigerator 6, which is the controlled object, remains stopped, it will become uncontrollable and the temperature at the cold water confluence outlet 10 will tend to drop, which is disadvantageous in terms of energy saving.
Therefore, in this case, it is advantageous to automatically switch the changeover switch 16 so that the first refrigerator 5 is controlled by the temperature regulator 15.

Also, depending on the temperature of the individual setting temperature, if it is a centrifugal chiller, it may be continued to operate at the maximum current value allowed by the chiller, or if it is a gas chiller/heater, the gas supply valve may be fully opened. There may be situations where the first refrigerator 5 must always be operated at maximum capacity, such as by continuing to generate maximum capacity, but if an abnormality occurs due to continuing to generate maximum capacity, it is necessary to prevent it with a safety device etc. Of course.

FIG. 2 shows another embodiment in which the first refrigerator 5 is mainly operated. The first refrigerator 5 is controlled by the temperature regulator 15 by the changeover switches 16 and 17, and the second refrigerator 6 is independently controlled by the temperature regulator 14. Therefore, the individual set temperature of the temperature regulator 14 is made higher than the combined water set temperature of the temperature regulator 15. The second refrigerator 6 is operated under a light load, and the first refrigerator 5 is operated under a high load for balance. At this time, even if the second refrigerator 6 is stopped, it is sufficient to continue controlling only the first refrigerator 5.

Since the energy situation varies depending on the season, the refrigerator to be controlled by the temperature regulator 15 is selected using the changeover switches 16 and 17 accordingly.

Note that the number of refrigerators is not limited to two, but may be more than two.

The present invention is applicable not only to the above-mentioned embodiments, but also to hot water temperature control during hot water production using a water cooler or heat pump,
It can also be applied to brine temperature control in industrial equipment.

〔Effect of the invention〕

According to the present invention, it is possible to save energy by selecting and mainly using a refrigerator that is advantageous in terms of energy depending on the situation at the time, and also to cope with difficulties in supplying specific energy. It is possible to provide a method for controlling the device, and it is possible to achieve an extremely large effect in terms of practical use and energy saving.

[Brief explanation of the drawing]

1 and 2 are flow diagrams of different embodiments of the present invention. 1... Cold water inlet, 2... Return header, 3... Pump, 4... Pump, 5... First refrigerator, 6...
2nd refrigerator, 7...Cold water outlet, 8...Cold water outlet,
9...Outbound header, 10...Cold water confluence outlet, 11
...Energy supply valve, 12...Energy supply valve,
13...Temperature regulator, 14...Temperature regulator, 15
...Temperature controller, 16...Selector switch, 17...
...Toggle switch.

Claims (1)

[Scope of Claims] 1. A method for controlling a cold/hot water device in which a plurality of cold/hot water machines that produce cold/hot water are arranged in parallel, and the cold/hot water from each cold/hot water machine is combined and supplied to a cold/hot water load. The first of a certain number of hot and cold water machines
Each of the cold/hot water machines in the group independently controls its capacity so that the cold/hot water outlet temperature of the cold/hot water machine reaches a predetermined individual setting temperature, and the other number of cold/hot water machines in the second group have a large cold/hot water load. Capacity control is performed so that the combined cold and hot water supplied to the cold and hot water load reaches a predetermined combined water set temperature according to the temperature, and the individual set temperature is set as follows with respect to the combined water set temperature. A method of controlling a hot and cold water device. Note A When mainly operating the 1st group (i) When producing cold water Individual set temperature < Combined water set temperature (ii) When producing hot water Individual set temperature > Combined water set temperature B When mainly operating the 2nd group (i) When producing cold water: Individual set temperature > Combined water set temperature (ii) When producing hot water: Individual set temperature <Combined water set temperature