JPS6021304B2 - Heat source demand control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat source demand control method for controlling process equipment so that the contracted value of the heat source is not exceeded.

In air conditioning control in buildings, cold and hot heat generated by nighttime electricity use is stored in a heat storage tank from refrigerators, which are the source of cold heat, and boilers, which are the source of overflow heat, and is supplied to the load when needed, and also serves as a type of heat tank. I am accomplishing it.

In order to handle the maximum peak load, a method is used that uses a heat source of cold water or hot water stored in a heat storage tank. However, in recent years, with the spread of district heating and cooling, an increasing number of newly constructed buildings are using district heating and cooling.

Monitoring and forecasting of the contract amount of hot and cold water for district heating and cooling is not done yet, and is currently left to the judgment of building maintenance personnel. Therefore, in order to judge the operating load, accurately predict the amount of heat used for the hot water, and select the necessary load within a range that does not exceed the contract, it was necessary to rely on conventional operating experience. It is desired that these factors be judged comprehensively, that the amount of heat used be predicted in some way, and that appropriate load control be performed. SUMMARY OF THE INVENTION An object of the present invention is to provide a heat source demand control method that measures the amount of heat received by process equipment for hot and cold water, accurately predicts the amount of heat scheduled to be used, and controls the amount of heat so as not to exceed the contracted range. Hereinafter, one embodiment of the present invention will be explained in detail using the drawings.

FIG. 1 is a configuration diagram showing an example of a system to which the present invention is applied. is input. For CPU3, setter 5
After predicting the amount of heat as shown in Figure 2 based on the value set by A message is output, and if the actual value is exceeded, a command is sent to the corresponding process equipment 9 to input or disconnect. Next, the operation of the present invention will be explained using FIGS. 2 and 3. The target upper limit value MT for the elapsed time T minutes is calculated from the set target value MTS set by the setting device 5, the contract time mX minutes, and the elapsed time T minutes. (Step 10) MT = Mdai x poison. ．． ．． ．． Rule MT: Target upper limit value TX: Contract time T: Elapsed time MTS: Setting target value Next, the amount of heat detected by calorimeter 1 is integrated for each unit time,
The amount of heat used in the elapsed time T minutes is assumed to be MU, and the amount of usable heat M yen in the elapsed time T minutes is calculated from this amount of used heat MU and the target upper limit value MT in the elapsed time T minutes.

(Step 11) M yen = MT - MU...'21 M yen: Usable amount of heat MU: Used amount of heat Next, the amount of used amount of heat MU at the elapsed time T minutes, the average amount of used amount of heat from (T-1) minutes to T minutes, and the end of monitoring. The expected amount of heat used MK at the end of monitoring is determined from the remaining time until the end of monitoring.

(Step 12) MK=MU+△M×(TX-T)...
'3' MK: Expected amount of heat used △M: Average amount of heat used from (T-1) to T minutes Next, compare the set target value MTS with the expected amount of heat used MX at the end of monitoring (Step 13) When the expected amount of heat used MK exceeds the set target value MTS, an alarm message is output to the CRT display device 4 (step 14) to inform the user of the abnormal state.

Furthermore, the target upper limit value MT and the current amount of heat used MU are compared (
Step 15) If the current amount of heat used MU exceeds the target upper limit value MT, proceed to step 16 and step 17, and perform multi-stage control of the load as follows, so that the amount of heat used MU reaches the set target value MTS within the contracted time. Perform optimal control so that Here, the optimal control method is a first stage control that reduces the amount of heat MU used by the process equipment 9 that uses the amount of heat, and
This is done through second-stage control that stops the operation.

Assuming that the process equipment 9 is an air conditioner and uses cold water, the temperature of the process equipment 9 can be set from the setting device 5 via the CPU 3.The CPU 3 controls the room temperature of the room to which the process equipment 9 supplies. It is assumed that it is under control. If the current amount of heat used exceeds the target upper limit value MT, the first stage control will change the temperature setting value of the process equipment 9 by △TI from the current setting value by the setting device 5 if the elapsed time is within TX/2 minutes. . Increase by 0.

If the elapsed time is within TX minutes from TX/2 minutes, the temperature set value of the process equipment 9 is increased by ΔT〆0 from the current set value by the setting device 5. Here, ΔTI°C and ΔT〆0 are temperature ranges set in advance by the setting device 5. Due to this action, the amount of heat fed to the process equipment 9 by the district cooling/heating receiving device 2 is determined by the heat capacity of the process equipment 9 and the amount of heat due to the temperature difference △TI°C or △T2°C (H x △TI or H x △T2 ), and in the next cycle, the amount of heat used MU
increase will be less. Furthermore, after the unit time has elapsed, the target upper limit value MT and the used amount of heat MU are compared again. As a result, if the amount of heat used MU exceeds the target upper limit value, this amount of heat used MU is further set to a set value (
For example, 95% of MTS) is compared to see if it is exceeded, and if it is not, the temperature setting value of the process equipment is changed as described above to reduce the amount of heat used.
On the other hand, if it is over, the second stage control described below is performed. That is, find the difference between the expected amount of heat used MX and the set target value MTS at that time, and
Process equipment 9 that can be stopped is selected according to the scheduled priority, and these process equipment 9. The process equipment 9 whose total heat capacity brings the value corresponding to the difference, that is, the estimated amount of heat used MK, to the set target value MTS is extracted from among them, and a stop command is output. By controlling the first stage and the second stage as described above, it is possible to perform optimal control of the heat load group without exceeding the contracted heat amount. As described above, according to the present invention, the heat load can be used to the maximum without exceeding the contracted heat amount.

In addition, it is possible to perform optimal load control with high thermal efficiency without paying a penalty fee for exceeding the contracted heat amount. Furthermore, although there are many ways to combine heat load groups,
By adopting a load selection method that maximizes thermal efficiency and considering a monthly load control method for energy saving, effective optimal control can be performed.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an example of a system to which the present invention is applied;
FIG. 2 is a flowchart for explaining the present invention, and FIG. 3 is a diagram for explaining the relationship between the set target value and the amount of heat used in the present invention. 1... Calorimeter, 2... District heating and cooling receiving device, 3... Arithmetic control device, 4... CRT
Display device, 5...Setting device, 9...Process equipment, MTX...Setting target value, MT...
...Target upper limit value, MU...Used hot child, MK...
・Estimated amount of heat used. Burning Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1 In a heat source demand control method that controls the amount of heat used by process equipment that operates to achieve a scheduled set temperature so that it does not exceed the contract value, the current target upper limit value is calculated from the target value set by the contract at regular intervals. Then, the expected amount of heat used at the end of monitoring is calculated based on the average amount of heat used in the vicinity, the remaining time until the end of monitoring, and the amount of heat used up to now, and the expected amount of heat used at the end of monitoring is determined to be higher than the set target value. If it exceeds the limit, an alarm is output, and the current target upper limit value is compared with the amount of heat used so far, and if the amount of heat used so far is greater, the temperature is set to at least reduce the amount of heat used. A heat source demand control method characterized by performing control to change a value by a predetermined amount.