JPH0447566Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a device that controls the capacity of a water cooler/heater in accordance with the load amount for air conditioning.

[Conventional technology]

When controlling the capacity of water chillers, boilers, gas absorption chillers, and hot water machines installed for air conditioning, conventionally the capacity was controlled to maintain the temperature of the return water via the air conditioning load at a constant value. control is becoming common.

[Problem that the invention attempts to solve]

However, in conventional control, the outlet temperature of the chiller/hot water machine changes depending on the air conditioning load and does not take into account changes in outside temperature. The capacity of the machine decreases regardless of the outside temperature, and water at a sufficient temperature cannot be supplied for the air conditioning load during operation, resulting in insufficient cooling or heating conditions.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention is constructed by the following means.

In other words, there is a means for determining the correction value α according to the outside temperature, and the addition result by this addition means is used as the correction value α.
a means for adding the return water temperature set value T _SP2 to the return water temperature set value T SP2, and the addition result by this addition means as the corrected set value T _SP2C ,
A means for determining the air conditioning load L according to the corrected set value T _SP2C and the detected return water temperature _T2 , and a basic set value T for the outlet temperature of the water chiller/heater according to the air conditioning load L determined by this means. A means for determining _BS , and a basic setting value _TBS determined by this means, and the above correction value α.
and a means for setting the addition result by the addition means as a corrected set value T _SPO and controlling the capacity of the water chiller/heater according to this corrected set value T _SPO and the detected outlet temperature T _O. It is.

[Effect]

Therefore, according to this invention, the correction value α determined according to the outside air temperature is added to the predetermined return water temperature set value T _SP2 , and from this the corrected set value T _SP2C is determined. The air conditioning load amount L is determined according to the corrected set value T _SP2C and the detected return water temperature T ₂ . Then, the above correction value α obtained according to the outside air temperature is added to the basic outlet temperature setting value T _BS obtained according to this air conditioning load amount L, and thereby the corrected setting value T _SPO is obtained. Yes, this corrected setting value
The capacity of the water cooler and hot water machine is controlled according to T _SPO and the detected outlet temperature T _O , and capacity control is performed taking outside air temperature into consideration, so that the capacity of the water chiller and hot water machine is always controlled to the optimum state.

〔Example〕

Hereinafter, details of the present invention will be explained with reference to figures showing embodiments.

FIG. 2 is an instrumentation diagram, showing pumps 1 ₁ to 1 _o and
A plurality of gas absorption type cold/hot water machines (hereinafter referred to as CHW) such as water chillers, water chillers, and boilers (hereinafter referred to as CHW) 2 ₁ - 2 _o are each installed, and the incoming water pumped by pumps 1 ₁ - 1 _o is
The water is supplied via CHW2 ₁ to 2 _o , through the header 3, through the pipe line 4, through the air conditioning load equipment (hereinafter referred to as LE) 5 such as a fan coil unit, to the header 7 as return water via the pipe line 6, and again to the pump. 1 ₁ to 1 _o , and circulates through the above routes.

Furthermore, a bypass pipe line 8 and a bypass valve 9 are provided between the headers 3 and 7, and the differential pressure between the headers 3 and 7 is measured by a differential pressure gauge 11, and control is performed according to this measured value. A device (hereinafter referred to as CNT) 12 gives an opening command to the bypass valve 9, controls the sending pressure of the incoming water, and also controls the temperature gauge 14 provided in the header 7.
While measuring the return water temperature T ₂ by
Thermometer 15 ₁ to 15 _o each on the delivery side pipe of CHW2 ₁ to 2 _o
are provided, and these control the opening degree of the capacity control valve of each CHW2 ₁ to _{2 o so} that the measured outlet temperature TO becomes a constant value, and also controls the return water temperature.
The load amount by LE5 is determined according to T ₂ , and the number of operating CHW2 ₁ to 2 _o is controlled accordingly.

In addition, the outside air temperature T ₃ is measured by the thermometer 16, and this value is taken in by the CNT 12 and used for determining correction values for capacity control.

Note that the CNT12 sends and receives data signals to and from the central control unit (not shown in the diagram) via the transmission path 19, and receives basic control data, etc., while also transmitting control status monitoring data, etc. It has become a thing.

Figure 3 is a block diagram of CNT12, which is a processor such as a microprocessor (hereinafter referred to as CPU).
21, fixed memory (hereinafter referred to as ROM) 2
2. Variable memory (hereinafter referred to as RAM) 23, and
Interfaces (hereinafter referred to as 1/F) 24 to 28 are arranged around the periphery, and these are connected by a bus bar.
Based on the input data Di such as each measurement output given via the I/F 24 and the data received via the communication I/F 26, the CPU 21 executes instructions in the ROM 22 to perform control calculations and make decisions during control. The output data D _O is sent as a command to each control target part via the I/F 25.

Note that the CPU 21 executes instructions while accessing necessary data from the RAM 23 during control calculations and control decisions.
Display data is sent to the display unit (hereinafter referred to as DP) 29 via I/F 27 to display the control status, and the keyboard (hereinafter referred to as DP) via I/F 28 is sent to the display unit (DP) 29 to display the control status.
KB) According to the operation output of 30, data is set or updated in RAM 23, and
These DPs 29 are used for display.

FIG. 4 is a front view showing the operation panel of the CNT 12, in which a multi-digit character display 31 and a plurality of indicator lights 32 are provided, which constitute a DP 29, and a KB 30 is provided. The display 31 displays data or numerical values using alphanumeric characters or symbols and numbers, while an indicator light 32 provided corresponding to the name plate 33 displays alarms and the like.

FIG. 5 is a flowchart of the capacity control situation by the CPU 21. First, the outside temperature "T ₃ read" 101 stored in the RAM 23 is periodically performed, and a correction value "α calculation" 102 is performed accordingly. . Next, the set value T _SP2 of the return water temperature stored in the RAM 23 in advance is “read T _SP2 ” 11
1, then “T _SP2 +α=T _SP2C ”112
, and return water temperature "T ₂ reading" 113 similar to step 101, and in accordance with these, "load amount calculation" 114 is performed by PID calculation etc., and the load amount L determined by this is Accordingly, the basic setting value " _TBS calculation" 115 is performed.

The relationship between the load amount L and the basic setting value _TBS is as follows:
In the case of air conditioning, the example is shown in Figure 6. If the outlet temperature T _O is 6°C when the load amount L is 100%, then when the load amount L is 0%, T _O
= 9°C, it is set slightly lower than before.

Next, the set value "T _SPO = T _BS + α"121 is calculated, and the outlet temperature "T _O read" 131 stored in the RAM 23 is periodically performed, and the PID etc. is calculated according to T _O and T _SPO . “Control calculation” 132 is performed, and the opening command value obtained through this is used as “capacity control command transmission”.
141 to the capacity control valves of CHW2 ₁ to 2 _o , and while repeating steps 101 and subsequent steps via "RET", the thermometers 15 ₁ to 15 _o are sent as _TO in step 131.
Each measured value is sequentially used, and the destination in step 141 is sequentially shifted correspondingly.

Note that the correction value α in step 102 is, for example, the seventh
As shown in the figure, when the outside temperature _T3 is 32℃ or higher, the
℃, 3℃ below 20℃, and an inverse proportional relationship between 20 and 32℃. In the case of T ₃ 20℃, as shown in Figure 6, the corrected set value T _SPO is 3℃ with respect to T _BS .
This is the value obtained by adding °C.

FIG. 1 is a functional block diagram for performing the above control, and shows the detected return water temperature T ₂ and the corrected set value obtained by adding the set value T _SP2 and the corrected value α using an adder 60. By T _SP2C , the computing unit 61 calculates the air conditioning load amount L and calculates _the basic setting value T _BS of the outlet temperature according to this air conditioning load amount L, while the α computing unit 62 calculates the correction value, and adder 63 adds _TBS and α.
After determining T _SPO , this is given to the control calculator 64 along with the detected outlet temperature T _O.
The opening command value D is determined by PID calculation, etc., and is sent to the gas valve, steam valve, vane, fuel valve, etc. determined according to the type of CHW.

Therefore, α corresponding to T ₃ is used, and the return water temperature set value T _SP2 is corrected by this α.
T _SP2C , the air conditioning load L is calculated according to the difference between T _SP2C and T ₂ , and according to this air conditioning load L,
T _BS is determined, T _SPO is determined based on this T _BS and α, and the capacity control valve is driven in the direction in which T _O matches T _SPO . Even if the load amount L increases or decreases, T According to condition ₃ , the CHW's capacity is always at its optimum, and water with a sufficient temperature for air conditioning is always supplied.

Note that the same applies not only during cooling but also during heating.

In addition, the relationships shown in Figures 6 and 7 can be obtained by using predetermined arithmetic expressions.
22 or RAM 23, and the contents may be read out and determined, and the relationship between these may be determined depending on the situation.

However, the configurations in Figures 1 to 4 can be selected arbitrarily depending on the situation, and in Figure 5, the steps can be replaced or replaced with equivalent ones according to the conditions. Alternatively, various modifications can be made, such as omitting unnecessary items.

[Effect of the invention]

As is clear from the above explanation, according to the present invention, the capacity of the water chiller/heater is controlled in consideration of the outside air temperature, so even if the air conditioning load changes, water at a sufficient temperature is always supplied. A great effect can be obtained in controlling the capacity of various types of water cooler/heater for air conditioning.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is a functional block diagram, Fig. 2 is an instrumentation diagram, Fig. 3 is a block diagram of CNT, and Fig. 4 is a front view showing the operation panel of CNT. Figure 5 is a flowchart of the control situation, Figure 6 is a diagram of the relationship between air conditioning load and outlet temperature set value,
FIG. 7 is a diagram showing the relationship between outside air temperature and correction value. 2 ₁ ~ 2 _o ...CHW (cold/hot water machine), 4, 6...pipeline,
5... LE (load equipment), 12... CNT (control device), 14, 15 ₁ ~ 15 _o , 16... thermometer, 2
1...CPU (processor), 22...ROM (fixed memory), 23...RAM (variable memory), 24~
28...I/F (interface), 60, 63
...Adder, 61...Arithmetic unit, 62...α arithmetic unit, 64...Control arithmetic unit.

Claims (1)

[Scope of Claim for Utility Model Registration] In a device that controls the capacity of a water chiller/heater according to the air conditioning load, a means for determining a correction value α according to outside temperature, and a method for returning water to the correction value α calculated by this means. A means for adding to the temperature set value T _SP2 , and a correction set value for the addition result by this adding means.
T _SP2C , this corrected set value T _SP2C and detected return water temperature
means for determining the air conditioning load amount _L in accordance with the air conditioning load _amount L determined by this means; means for adding the corrected value α to the basic set value _TBS , and the addition result by this adding means to the corrected set value _TSPO.
A capacity control device for a water chiller/heater, comprising means for controlling the capacity of the chiller/heater according to the corrected set value T _SPO and the detected outlet temperature _TO .