JP2577141B2 - Heat storage type heat source device and its peak cut control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat storage type heat source device and a peak cut control method therefor, and more particularly, to an optimum peak cut type for an ice storage type heat source device having a sufficient capacity for a load on a building. The present invention relates to a peak cut control method for a heat storage type heat source device that automatically performs setting.

[0002]

2. Description of the Related Art The purpose of an ice storage heat source device is to correct a difference in power demand between day and night and to level power demand. Therefore, during the summer time when power demand is greatest (13:00 to 15:00), the so-called peak cut function of forcibly stopping the heat source device and performing air conditioning only with the heat stored in the heat storage tank is provided. This is one of the most important functions of the ice storage type heat source device.

[0003] By the way, in the past, when peak cutting is performed, for example, “Study on ice heat storage method for large buildings” (Academic Transactions on Air Conditioning and Sanitary Engineering, 1985. 9 /
As described in (30-10 / 2), a reduction in the daily accumulation capacity of the ice storage type heat source device due to the peak cut is considered. That is, when performing the peak cut, since the heat source device is forcibly stopped during the peak cut operation, the operation time of the heat source device for one day is shortened, and the integration capability of one day is reduced accordingly. In this method, the capacity of the apparatus is selected in consideration of the decrease in the integration capacity, and a peak cut time is set by a timer or the like (for example, 13:00 to 15:00) to perform a peak cut operation. Alternatively, the operation of the heat source device is stopped by manual operation while observing the operation status, and the peak cut is performed by a method of performing the peak cut operation.

[0004]

In the above prior art, no consideration has been given to automatic setting of the peak cut time, and the following problems have been encountered. (1) In general, for example, in selecting an air conditioner, even when peak cut is not considered, the air conditioner is usually selected with a margin of about 10% with respect to an expected load. Therefore, the heat storage remains until about one hour before the end of the air conditioning, and the operation pattern is such that the entire heat storage amount is radiated just before the end of the air conditioning. However, if the peak cut time is automatically set so as to dissipate the amount of heat finally radiated and the means for controlling the peak cut operation can be provided without being conscious of the peak cut, the load can be reduced. , While contributing to the equalization of power demand.

(2) When the equipment capacity is selected without particularly considering the peak cut as in (1) above, it is unclear how long the peak cut is possible, and the peak cut with a timer as in the prior art is not clear. , It was difficult to determine the time to be set. Also, for consumers who are not conscious of peak cut, setting the timer is a heavy burden.

(3) When selecting equipment capacity in consideration of peak cut, load estimation is performed in advance to determine equipment capacity. However, when the load prediction does not match the actual load, if the initially set peak cut timer is set, the load may not be able to be covered immediately before the end of the air conditioning.

An object of the present invention has been made in view of the above problems, and an object of the present invention is to provide a regenerative heat source apparatus capable of effectively performing peak cutting while satisfying the demand for heat from a load. It is to provide a peak cut control method.

[0008]

In order to achieve the above object, a heat storage type heat source device according to the present invention comprises a heat source device, a heat storage tank connected to the heat source device, and a means for controlling these. In a regenerative heat source device that performs heat storage and cold storage by phase change using nighttime electric power and uses this heat for daytime load, a means for detecting the state of the load, a means for recording the state of the load, Means for setting a peak cut time based on the recorded load state.

Further, in order to achieve the above object, a configuration of a peak cut control method for a regenerative heat source device according to the present invention comprises a heat source device, a heat storage tank connected to the heat source device, and means for controlling these. The method of controlling a regenerative heat source device that uses nighttime power to perform heat storage and cold storage using a phase change and uses this heat for a daytime load, detects the state of the load for a predetermined period, and detects the state of the load. Record the data, extract the data of the maximum load day from the stored load data , calculate the daily integrated load on the maximum load day, and calculate the integrated load.
And the daily accumulation capacity of the regenerative heat source device,
Calculate the peak cut time from the capacity per unit time
And set the peak cut time during the operation schedule,
The peak cut control is performed based on the set peak cut time.

[0010] More specifically, the extraction of the data of the maximum load day of recorded has been loaded, the cold water inlet and outlet for the heat storage tank, the average temperature difference between day cold performed by selecting the largest day, or , Is calculated by calculating the daily accumulated load and selecting the largest day.

The following is a more specific description. An operation state detection unit that functions as a means for detecting a state of the load and detects various operation data is provided.
An operation state storage section for storing various operation data, which functions as a means for recording the state of the load, is provided inside the storage device of the microcomputer, and the microcomputer controls the actual load based on the data stored in the operation state storage section. The margin is calculated, and the peak cut time is automatically set based on the calculation result.

[0012]

The operation state detecting section is, for example, a detector mounting section for detecting the temperature of the cold water inlet and the outlet of the heat storage tank, and detects the cold water inlet temperature and the cold water outlet temperature of the ice heat storage type heat source device at each time. Detect changes in daily load. The operation state storage unit is provided in the storage device of the microcomputer, and stores data detected by the operation state detection unit for a certain period. After a lapse of a certain period, the microcomputer selects data of the maximum load day from the data in the operation state storage unit, and calculates a difference between the daily integrated load calorie of the maximum load day and the daily integrated capacity of the ice storage type heat source device.

A peak cut time corresponding to a difference between the daily accumulated heat quantity of the day of the maximum load and the daily accumulated capacity of the ice storage type heat source device is calculated in the microcomputer, and the peak cut time is set. This makes it possible to automatically determine and set the amount of heat that can be used for peak cut, eliminating the burden of determining the set value of the timer and setting the timer as in the past, and at the same time, especially reducing the peak cut. The peak cut can be realized without being conscious, and the leveling of power demand can be promoted.

[0014] Further, even with the ice storage type heat source device selected on the premise of performing the peak cut, in the conventional method of predicting the load and setting the timer, if the load is not predicted, there is a possibility that a problem that the load on the air conditioner near the end no longer corresponds threshold occurs, but according to the above method, can be automatically performed the best Pikukatsuto time set based on the actual load.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. 1 is a system diagram of an ice storage type heat source device according to one embodiment of the present invention, FIG. 2 is a configuration diagram of a microcomputer provided in a control panel of the device of FIG. 1, and FIG. 3 is a heat source in the device of FIG. It is a diagram of start / stop control of a device. In FIG. 1, 1
Is a heat source device, for example, a refrigerator, and 2 is a brine / water heat exchanger, which performs heat exchange between the antifreeze cooled by the heat source device 1 and cold water returned from the load during air-conditioning operation. Reference numeral 3 denotes a heat storage tank for storing heat generated using nighttime electric power, and 4 denotes an ice making heat exchanger provided in the heat storage tank 3, and the ice making heat exchanger 4 is a heat source device using nighttime electric power. 1 is operated to exchange heat between low-temperature brine generated and water in the heat storage tank 3 to form ice in the heat storage tank 3.

5 is a chilled water pipe for guiding chilled water from a load;
Are water spray pipes for spraying cold water exiting the brine / water heat exchanger 2 in the heat storage tank 3, and 7 and 8 are control valves for controlling the amount of cold water flowing into the heat storage tank 3 to control the temperature of the cold water outlet. , 9 are temperature detectors for detecting the chilled water outlet temperature, 10
Is a temperature controller that issues an open / close signal to the control valve 8 based on a signal from the temperature detector 9, and 11 is a brine pipe that connects the heat source device 1 to the brine / water heat exchanger 2 and the ice making heat exchanger 4. 12, 13, 14 and 15 are switching valves for switching the flow direction of the brine between the air-conditioning operation and the heat storage operation;
Is a water level detector provided in the heat storage tank 3. The water level detector 16 detects a water level in order to estimate a heat storage amount during the heat storage operation and a heat storage remaining amount during the air conditioning operation. 17
Is a conduit for guiding the water level to the water level detector 16, 18 is a temperature detector, and 29 is a cold water pump.

Reference numerals 19, 20, and 21 are the core of the present invention. That is, 19 is a control panel with a built-in microcomputer, and 20 is a chilled water inlet temperature detector for the heat storage tank 3 of the ice storage type heat source device (specifically, a brine / water heat exchanger 2).
Is a chilled water outlet temperature detector for the heat storage tank 3 of the ice heat storage type heat source device. The chilled water inlet temperature detector 20 and the chilled water outlet temperature detector 21 correspond to an operating state detecting unit that functions as a unit that detects a state of a load. The microcomputer provided in the control panel 19 functions as a means for recording a load state, that is, an operation state storage unit, and a means for setting a peak cut time based on the recorded load state.

The microcomputer has a CPU as shown in FIG.
(Central processing unit) 24, memory (storage unit) 22,
A bus 2 for transmitting data between the CPU 24 and the memory 22
3. An input interface 25 for inputting a signal from the outside and converting it to a signal for the CPU 24, a cable 28 for transmitting data between the input interface 25 and the CPU 24, and an output for converting a signal from the CPU 24 to a signal for an external device Interface 26 and CP
It comprises a cable 27 for transmitting data between the U24 and the output interface 26, and processes input signals and output signals in accordance with software logic stored in the memory 22.

Next, the general operation of the ice storage type heat source device will be described. The operation of the ice storage type heat source device includes a heat storage operation at night and an air conditioning operation at daytime. In the nighttime heat storage operation, the heat source device 1 (refrigerator) is operated, and the brine pipe 11 is operated.
The inside of the heat storage tank 3 is cooled to 0 ° C. or lower, and heat is stored by changing the water in the heat storage tank 3 into ice by the ice making heat exchanger 4 in the heat storage tank 3. Normally, such a heat storage operation is performed during a nighttime discount period (22:00 to 8:00). In addition,
In order to reduce the size of the heat source device 1, there is also a method of performing a heat storage operation in addition to the night discount time zone. In addition, the heat storage amount is always measured by the water level detector 16 from a water level difference from a reference position (a position where the heat storage amount is zero), and when the water level difference becomes a predetermined value,
It is determined that the heat storage has been completed, and the heat storage operation ends.

During daytime cooling operation, the heat source equipment 1 (refrigerator)
Is operated to cool the brine to about 3 ° C., and lead to the brine / water heat exchanger 2 through the brine pipe 11, where:
By performing heat exchange with cold water returned from the load,
Reduce the temperature of the cold water. Thus, the control valves 7, 8 are controlled by the temperature detector 9 and the temperature controller 10 so that the chilled water exiting the brine / water heat exchanger 2 is brought to a predetermined temperature (for example, 7 ° C.) at the outlet of the unit. Control. Also,
In the operation / stop control of the heat source device 1, the difference in water level from the reference water level detected by the water level detector 16 is converted into a heat storage amount inside the microcomputer in order to use the heat storage at night as much as possible, and the operation as shown in FIG. It is controlled inside the microcomputer by the / stop curve. The above-described heat storage operation control and air conditioning operation control are controlled by a control panel 19 having a microcomputer inside.

Next, an automatic peak cut setting method, which is a feature of the present invention, will be described with reference to FIGS. FIG. 4 is a flowchart illustrating an example of a control method of the conventional ice storage air conditioning system, and FIG. 5 is a flowchart illustrating an automatic peak cut control method of the ice storage air conditioning system of the present embodiment. In the following description, step NO. The number is written in parentheses. In an air conditioning system using a conventional ice storage type heat source device, as shown in FIG. 4, an operation schedule such as an air conditioning start time, an air conditioning end time, a heat storage start time, a peak cut start time, and a peak cut time is set (step S1). 30), operation is started (step 31).

After the operation is started, it is determined whether the current time is the air-conditioning operation time or the heat storage operation time of the input schedule, or neither of them (steps 32, 50, 54).
If the current time is the air-conditioning operation time, a start command and a stop command are issued from the microcomputer of the control panel 19 to the heat source device 1 based on a start / stop control curve of the heat source device 1 (for example, a chiller of a refrigerator) shown in FIG. If a heat source device activation command is issued at this time (step 34), the heat source device 1 starts operating (step 35). First, the peak cut time is set. If the peak cut start time is reached during operation, the heat source device 1 stops operating (steps 36 and 37). Thereafter, when the time elapses and the peak cut time ends (step 38), the start / stop of the heat source device 1 is controlled again by the microcomputer (40, 41, 43, 44). If the air-conditioning time set in the schedule is completed while the heat source device 1 is being started (steps 42 and 45), the heat source device 1 stops (step 54) and waits for the heat storage time to come.

If the peak cut is not set first, or before the set peak cut time, the heat source device 1 repeats starting and stopping according to a command from the microcomputer (steps 47 and 48). When the air-conditioning time ends while the start and stop are repeated, the heat source device 1 stops (steps 46 and 49) and waits for the heat storage time to come. next,
When the heat storage time comes, the heat source device 1 starts operating and performs the ice making operation. Then, when the heat storage is completed or when the heat storage time has ended, the heat source device 1 stops and ends the heat storage operation. The above is the control procedure of the conventional ice storage type heat source device.

Next, a peak cut control method of the ice storage type heat source device of the present embodiment will be described. In FIG. 5, hatched step portions are features of the present invention that are different from FIG. The description of the same parts as those of the prior art shown in FIG. 4 is omitted. The air conditioning operation is started, and the cold water pump 2
9 starts, the temperature detectors 20 and 21 detect the cold water inlet temperature and the cold water outlet temperature of the ice storage heat source device, respectively.
The detected data is sent to the microcomputer of the control panel 19. In the microcomputer, the sent temperature data is sequentially stored in a memory 22.
And collects operation data (step 55).

Such data collection is continued for a certain period, such as one season or one year. Here, there are a method of setting the data collection period at the time of setting the operation schedule (step 30) and a method of storing the initial value in the microcomputer in advance. When the data collection for a certain period is completed (step 56), the data of the maximum load day is extracted from the accumulated operation data (step 57). In the method of extraction, when the cold water flow rate is constant, the day on which the average daily temperature difference of the cold water at the cold water inlet / outlet with respect to the ice storage heat source device, particularly the heat storage tank, is selected. Or,
It is conceivable to calculate the daily accumulated load and select the largest day.

Next, the data of the maximum load day extracted above
From, the hourly load (kcal / h) is integrated per day
To calculate the daily integrated load (kcal / day) (step 5).
8). If the calculation of the daily accumulated load has already been performed when the maximum load day is extracted, it is not necessary to perform the calculation again. Next, heat source equipment cooling capacity (kcal / h) x air conditioning time
(H) The difference between the integrated cooling capacity of the ice storage type heat source device given by + ice heat storage amount (kcal) and the daily integrated load calculated above is obtained, and the remaining amount of the ice storage type heat source device with respect to the actual load is obtained.
Calculate the room temperature and divide it by the cooling capacity per unit time of the heat source equipment 1 , so that only the heat stored in the heat storage tank becomes empty.
So that peak cut time can be calculated.
That (step 59). Finally, the peak cut time calculated above is registered in the schedule in the microcomputer, and the setting of the peak cut time is completed (step 60).

If the schedule of the peak cut operation is not set at first in the operation schedule setting (step 30), the peak cut operation is performed according to the schedule set by the above method. If the schedule of the peak cut operation is set first in the operation schedule setting (step 30), the initial setting is ignored and the peak cut operation is performed according to the schedule calculated by the above method.

The hardware for performing the above-mentioned control uses the microcomputer, which performs the conventional operation schedule, the start / stop of the heat source device 1, and the heat storage amount control, in a time sharing manner to perform the above-mentioned automatic peak cut. In addition to performing control, it is also possible to independently prepare a microcomputer for automatic peak cut control and execute processing in parallel, in addition to a microcomputer that performs control other than peak cut.

In the above embodiment, the air conditioning system using the ice storage type heat source device has been described.
In addition to the ice storage type heat source device, a heat storage type heat source device using a heat medium other than ice (for example, a latent heat storage medium such as thione sulfuric acid) for storing heat using nighttime electric power and performing air conditioning using this heat during the day. Can be applied to the peak cut control.

[0030]

As described above in detail, according to the present invention, a regenerative heat source device capable of effectively performing peak cutting while satisfying the demand for heat from a load, and a peak cut control method thereof are provided. Can be provided. In other words, the peak cut can be automatically set, and
An optimum peak cut operation can be performed in consideration of the load characteristics of a building or the like and the capacity of the regenerative heat source device.

[Brief description of the drawings]

FIG. 1 is a system diagram of an ice storage type heat source device according to one embodiment of the present invention.

FIG. 2 is a configuration diagram of a microcomputer provided in a control panel of the apparatus of FIG.

FIG. 3 is a diagram of start / stop control of a heat source device in the apparatus of FIG. 1;

FIG. 4 is a flowchart illustrating an example of a control method of the conventional ice storage air conditioning system.

FIG. 5 is a flowchart illustrating an automatic peak cut control method of the ice thermal storage air conditioning system of the present embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 heat source equipment 2 brine / water heat exchanger 3 heat storage tank 4 ice making heat exchanger 5 chilled water pipe 7, 8 control valve 16 water level detector 18 temperature detector 19 control panel 20 chilled water inlet temperature detector 21 chilled water outlet temperature detector 22 Memory 24 CPU

Claims (4)

(57) [Claims] 1. A heat source device, a heat storage tank connected to the heat source device, and a means for controlling the heat source device, performing heat storage and cold storage by phase change using nighttime electric power, and transferring the heat to a daytime load. In the regenerative heat source device to be used, a means for detecting a load state, a means for recording the load state, and a means for setting a peak cut time based on the recorded load state are provided. Regenerative heat source device. 2. A heat source device, a heat storage tank connected to the heat source device, and means for controlling the heat source device, performing heat storage and cold storage by phase change using nighttime electric power, and transferring the heat to a daytime load. In the control method of the regenerative heat source device to be used, the state of the load is detected for a predetermined period, the state of the load is recorded, the data of the maximum load day is extracted from the stored load data, and the maximum load Calculate the daily load of the day,
Daily accumulation capacity of the heat storage type heat source device and unit time of the heat source device
Calculate the peak cut time from
A peak cut control method for a regenerative heat source device , wherein a peak cut time is set during a schedule, and peak cut control is performed based on the set peak cut time. 3. A method according to claim 3, wherein the data of the maximum load day among the recorded loads is extracted by selecting a day at which the average temperature difference of the cold water at the cold water inlet / outlet with respect to the heat storage tank is largest. Item 4. The peak cut control method for a regenerative heat source device according to any one of Items 2 and 3. 4. The method according to claim 2, wherein data of the maximum load day among the recorded loads is extracted by calculating a daily integrated load and selecting the largest day.
A peak cut control method for the regenerative heat source device according to any one of the claims.