JPH01244228A - Control method for heat accumulation type air-conditioning system - Google Patents

Abstract

PURPOSE:To reduce an ice-making amount during the night when a load is low and a remaining quantity of heat in a heat accumulating tank is high, by a method wherein when a water temperature in a heat accumulating tank before ice-making operation during the night is started is below a given value and an amount of ice in the heat accumulating tank exceeds a given value, an ice-making amount in the heat accumulating tank is reduced. CONSTITUTION:A heat accumulating tank 1 having a first heat exchanger 4 to make ice by using brine, a radiator situated in a room to be air-conditioned, and a second heat exchanger 7 to cool water by using brine fed from a heat source machine are interconnected through a piping so that water is circulated. Through drive of the heat source machine during the night, water in the heat accumulating tank is cooled to make ice, and during the daytime, water in the heat accumulating tank is circulated to a radiator to perform air-conditioning. When the load of a room to be air-conditioned is high, through drive of the heat source machine, water is cooled by means of a second heat-exchanger. In this heat accumulation type air conditioning system, where a water temperature in the heat accumulating tank, before ice making operation during the night is started, is below a given value or an amount of ice in the heat accumulating tank exceeds a given value, an ice-making amount in the heat accumulating tank is reduced. Thereby, when a cooling load during the daytime is low and a remaining ice amount in the heat accumulating tank is high, the set value of an ice-making amount during the night is reduced to reduce a remaining ice amount in a preceding day.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a control method for a regenerative air conditioning system that stores heat through ice at night and performs cooling operation during the day by cooling the ice. (1) Prior Art Conventional technology for controlling a regenerative air conditioning system that stores heat at night is described in Japanese Patent Publication No. 17332/1983. The system described in this bulletin uses late-night electricity to store heat in the form of hot or cold water in a heat storage tank, and when daytime air conditioning is required, the stored heat is extracted and used for air conditioning. 'The amount of heat required for daytime air conditioning is predicted from the relationship between the past outside air temperature and the amount of residual heat so that the amount of heat available (residual heat amount) in the heat storage tank is minimized when air conditioning is finished, and the amount of heat required for daytime air conditioning is The heat storage operation is performed by modifying the predicted amount of heat according to the temperature.

(c) Problems to be solved by the invention In such conventional regenerative air conditioning systems, the operation time is set to cool or heat the heat medium during the middle of the night when electricity is not supplied, and the system is used during the day. The premise was that all of the heat storage would be obtained from late-night electricity.

Therefore, the amount of heat medium stored in the heat storage tank is necessary to withstand use during the day, and the heat source equipment must be able to store all the heat medium stored in the heat storage tank during the hours when electricity is supplied in the middle of the night. Since it requires the ability to cool or heat up to a temperature of

In addition, since the total amount of heat stored by the heat medium is large, accuracy is required in predicting the amount of heat stored at night, and the prediction conditions include correction based on the outside temperature of the past few days, correction based on the amount of residual heat, and a time conversion factor. Since this is carried out using various types of condition detectors, setting of the amount of heat storage becomes complicated, and the control device also tends to become complicated.

In view of these problems, the present invention provides an optimal control system that allows sufficient air conditioning even when using a small-capacity heat source device.

(d) Means for Solving the Problems The present invention provides a heat storage tank having a first heat exchanger for making ice using the water stored therein and the brine supplied from the machine, and a heat storage tank provided in a conditioned room. The radiator is connected with a second heat exchanger that cools water using brine that can be supplied from the heat source machine, using piping so that the water circulates. In the control method of a regenerative air conditioning system that cools water using a heat exchanger, when the water temperature in the heat storage tank is below a predetermined temperature or the amount of ice in the heat storage tank is above a predetermined amount before starting ice making operation at night, This is to reduce the amount of ice made in the heat storage tank and set it to t.

(f) Function In the control method of the regenerative air conditioning system configured in this way, when the load during the day is large and the amount of heat stored in the thermal storage tank is insufficient, the first heat exchanger is used to assist the air conditioning operation. conduct,
When the load is small and the amount of residual heat in the heat storage tank is large, the amount of ice made at night is reduced.

(F> Example) Hereinafter, an example of the present invention will be explained based on the drawings. Fig. 1 is a schematic diagram of this system. 1 is a heat storage tank, and this heat storage tank stores water used as a heat medium. an ice-making section 2,
It has a first heat exchanger 4 that cools or heats water in the ice making section 2. By driving the pump 5, the water in the ice making section 2 is pumped through the radiator (provided in the conditioned room) and the second
The heat exchanger 7 sequentially flows through the heat exchanger 7 and returns to the heat storage tank 1 again.

8 is a mixing valve, and the temperature of cold and hot water flowing to the pump 5 side is always almost constant (for example, about 7°C during cooling operation).
1. Automatically adjusts the mixing ratio of the amount of water flowing in from the second heat exchanger 7 side and the amount of water flowing in from the heat storage tank 1 side so that the temperature is approximately 45°C during heating operation. It is.

The second heat exchanger 7 and the first heat exchanger 4 are connected in parallel through a piping circuit, and when the solenoid valve 10 opens, brine from the heat source device 11 flows into the second heat exchanger 7. Water is cooled or heated by Further, when the electromagnetic valve 12 is opened, brine flows into the first heat exchanger 4 to make ice in the heat storage tank 1. Note that 13 is a brine circulation pump, and 14 is a one-way valve.

Reference numeral 15 denotes a control unit of this system, which detects the detection value of a temperature detector 16 that detects the temperature of cold and hot water in the heat storage tank 1, and the detection value of a water amount detector 17 that detects the amount of ice in the ice making section 2 of the heat storage tank 1. The operation of each device is controlled based on the detected value of the temperature detector 18 which detects the temperature of the cold and hot water flowing from the radiator 6 to the second heat exchanger 7.

FIGS. 2 and 3 are operation explanatory diagrams showing the main operations of the regenerative air conditioning system by the control unit 15. This system has 24
This operation explanatory diagram represents a series of operations because the operation is constant throughout time. First time 8:00-18
In the cooling operation performed between :00, the pump 5 is driven in step S to circulate cold and hot water to the radiator 6. By this, it is determined whether the temperature T'+a of the water flowing from the radiator 6 to the second heat exchanger 7 satisfies "l',, >12", and when "T 1m>12" operates the heat source device 11, and the second heat exchanger 7 performs auxiliary cooling of water.

After 18:00, the cooling mode ends and pump 5
stop operating. Next, in step S, the temperature of the cold and hot water in the heat storage tank 1 is T1. satisfies "Tls≦5", and determines whether the cold/hot water temperature T1. When satisfies "T≦5", the ice making amount A is set to A=50%, and also when the remaining ice amount TIF in the heat storage tank 1 is "'ray≧20%", A=50.
%, otherwise set A=100%.

Thereafter, after the time 22:00, the power supply to the heat source device 1 is switched to the late-night power supply, and then the ice-making operation in the ice-making mode is started. This ice-making operation ends in step S4 when the ice-making amount TI in the heat storage tank 1 becomes "T, γ ≥ A% of the total volume," or when the time reaches 8200 on the next day. In this ice-making operation, the heat source device 11 is operated, the electromagnetic valve 12 is opened, and ice is made in the heat storage tank 1 by cooling from the first heat exchanger 4.

Note that the amount of ice to be made can be determined from a rise in the level of cold and hot water in the heat storage tank 1, a temperature change using a temperature detector, and the like.

In the regenerative air conditioning system configured as described above, the set value for the amount of ice made at night is reduced when the daytime load is small and there is a large amount of ice remaining in the thermal storage tank, or when the water temperature is low.

(G) Effects of the Invention The present invention includes a heat storage tank having a first heat exchanger that makes ice from water stored therein using brine supplied from a heat source device, a radiator provided in a conditioned room, A second heat exchanger that cools water using brine supplied from the heat source machine is connected with piping so that water circulates, and the heat source machine is driven at night to make ice from the water in the heat storage tank. A regenerative air conditioning system that circulates water in a thermal storage tank to a radiator during the day to perform air conditioning, and when the load in the conditioned room is large, it drives a heat source unit and cools the water with a second heat exchanger. In the control method, when the water temperature in the heat storage tank is below a predetermined temperature before starting ice making operation at night, or when the amount of ice in the heat storage tank is above the predetermined amount, ice making in the heat storage tank is stopped. Since the amount is set to be reduced, when the cooling load during the day is small and the amount of water remaining in the heat storage tank is large, the set value for the amount of ice made at night is reduced to reduce the amount of remaining water the next day.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a system showing an embodiment of the present invention;
1 is an operation explanatory diagram showing the main operations of the system shown in FIG. 1, and FIG. 3 is an operation explanatory diagram showing the main operations of the system shown in FIG. 1... Heat storage tank, 11... Heat source machine, 16...
Temperature detector.

Claims (1)

[Claims] (1) A heat storage tank having a first heat exchanger that makes ice from water stored therein using brine supplied from a heat source device;
A radiator installed in the conditioned room and a second heat exchanger that cools water using brine supplied from the heat source device are connected via piping so that water circulates, and the heat source device is driven at night. During the day, the water in the heat storage tank is circulated to the radiator for air conditioning, and when the load in the room to be conditioned is large, the heat source unit is driven and the second heat exchanger is used. In the control method of a thermal storage air conditioning system that cools water with A control method for a regenerative air conditioning system that is characterized by a setting that reduces the amount of ice produced within the system.