JPH0447565Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for controlling the operating capacity of an absorption type water chiller/heater such as a gas absorption type chiller/heater.

[Conventional technology]

Absorption type water coolers use an absorption liquid such as lithium bromide to heat and circulate it. Gas valves adjust the amount of heating fuel gas in the high-temperature regenerator, and the steam regenerated by the boiler is controlled. It is equipped with capacity control valves such as steam valves that adjust the supply amount, but even if the opening degree of these control valves is changed, the operating capacity does not respond immediately, and the operating capacity does not respond to changes in the air conditioning load. It is difficult to immediately follow changes in load, so multiple chiller/heater units are installed, the number of units in operation is changed, and the control valve opening degree is controlled solely by the temperature of the chilled/hot water being sent out. It has become a thing.

[Problem that the invention attempts to solve]

Therefore, in the past, it was not customary to set the capacity control valve opening to a low opening at startup and then gradually increase the opening to the optimum opening.
The number of repeated shutdowns increases, and excess energy is consumed for heating to replenish the boiler's cooling capacity at startup.During shutdowns, it is necessary to add moisture to the absorption liquid, which necessitates dilution operation. This causes problems such as ineffective energy being consumed.

[Means for solving problems]

In order to solve the above-mentioned problem, the present invention is constructed by the following means. That is, a device that controls the number of absorption type water chillers and hot water machines in operation according to the air conditioning load amount, and controls the opening degree of the capacity control valve of the chiller and hot water machine to control its operating capacity. , a detection means for detecting that any one of the above-mentioned cold/hot water machines is started in standalone operation and low capacity operation, a time limit means for maintaining the detected power of the detection means for a certain period of time, and a time limit output of the time limit means. and sending means for supplying a low opening degree signal to the capacity control valve of the water chiller/heater which is activated in independent operation and low capacity operation.

[Effect]

Therefore, according to this invention, when it is detected that one of the plurality of absorption type water chiller/heaters is started in independent operation and low capacity operation, the timer is set according to the detection power of the absorption type water chiller/heater. The detected force is maintained for a certain period of time, and in accordance with this time-limited output, the sending means gives a low opening degree signal to the capacity control valve of the water chiller/heater which is started in independent operation and low capacity operation. For this reason, the capacity control valve of the water chiller/heater, which is started in standalone operation and low capacity operation, starts at a low opening for a certain period of time and then shifts to the appropriate opening, thereby avoiding the start of operation due to excessive capacity. The number of starts and stops during low-ability exercise is reduced, which improves energy consumption.

〔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 absorption type chiller/heaters (hereinafter referred to as CHWs) such as gas absorption type _chiller /heaters and _chillers are installed.
The incoming water pumped by pump 1 ₁ ~ 1 _o is CHW2 ₁
~1 _o , is supplied via a header 3 and a conduit 4, and is supplied to load equipment such as a fan coil unit (hereinafter referred to as
LE) 5, the water reaches the header 7 as return water through the pipe 6, and is again pumped by the pumps ₁₁ to _1o .
It is designed to circulate 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 monitoring the return water temperature _T2 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 capacity control valve opening degree of each CHW2 ₁ to _2o individually in the direction that the measured incoming water temperature T _O becomes a constant value, and also controls the capacity control valve opening degree command. Based on the value, the load amount by LE5 is determined, and the number of operating CHW2 ₁ to 2 _o is controlled accordingly.

The CNT12 sends and receives data signals to and from the central control unit (not shown in the diagram) via the transmission line 19, and while receiving basic control data, it also sends control status monitoring data, etc. It has become something to do.

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 I/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 control decisions. , 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 showing the control situation during low capacity operation by the CPU 21.
01, and if this is Y (YES), further determines "Capacity reduction?" 102, and if this is also Y, "send stop command" 111 to the CHW operating independently, If cooling is in progress, return water temperature
“T ₂ > T _sp ”1 by comparing T ₂ and set temperature T _sp
12, and if it becomes Y, solo operation is started.
The CHW wakes up and performs "send command" 121, then "sends minimum opening signal" 122 to the capacity control valve of this, and "holds this state for a certain period of time" 123 using a timer configured in the CPU 21.
After performing this, the program moves to a general "normal control" 124, and repeats steps 101 and subsequent steps via "RET".

FIG. 1 is a functional block diagram that performs the above control, in which a number control unit 61 using a well-known method determines the number of operating CHW2 ₁ to 2 _o according to the air conditioning load, and starts up the CHW2 in accordance with this. Command signal S ₁ ~ _{S o}
CHW2 ₁ ~ 2 _o , and these signals S ₁ ~
On the other hand, the logic circuit 62 detects either island operation based on S _o , and the outgoing water temperature T _O
The control calculator 63 is set according to the set temperature TOSP.
It performs control calculations such as PID, and provides an opening command signal D to the capacity control valve of the CHW operating independently via a switch 64 serving as a sending means.

Further, the output of the control calculator 63 is detected to be below a certain value by the comparator 65, and the detected power is given to the AND circuit 66 as a low capacity operation signal. Since the operation detection signal is also given, the number control unit 61
When the unit sends a start command signal for independent operation, if the detection force of the comparator 65 is also generated at this time, the AND
The circuit 66 sends out an output, which indicates the start of individual operation and low capacity operation. In response, a timer 67 is started, and its timed output drives the switch 64 for a certain period of time to control the opening. This is used to select the set value D _SP .

Therefore, the opening setting value _DSP , which is set in advance to a low opening such as the minimum opening, is sent as the opening command signal D, and as a result, the independently operating CHW is started at a low opening and is in this state. is maintained until the timer 67 as a timer expires, and then the control calculator 6
Return to the normal control state by the output of step 3.

Therefore, when starting individual operation due to low capacity operation, the capacity control valve starts with a low opening and gradually shifts to the appropriate opening, so the operating capacity does not become excessive and once started, it can be operated for a relatively long time. Operation continues, the number of repeated startups and stops is reduced, and the energy loss associated with this is reduced.

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

[Effect of idea]

As is clear from the above explanation, according to the present invention, when any one of the plurality of absorption type water chillers/heaters is started up individually, the capacity control valve of the chiller/heater is kept at a low opening for a certain period of time to prevent startup. In addition, since the opening is shifted to the appropriate opening degree, operation starts due to excessive capacity are avoided, and the number of repeated starts and stops is reduced, resulting in a reduction in energy consumption. A great effect can be obtained on the machine.

[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. FIG. 5 is a flowchart of the control situation. 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 ...Thermometer, 21...
CPU (processor), 22...ROM (fixed memory), 23...RAM (variable memory), 24-28
...I/F (interface), 62...Theoretical circuit, 63...Control calculator, 64...Switch, 6
5... Comparator, 66... AND circuit, 67... Timer.

Claims (1)

[Scope of Claim for Utility Model Registration] Controlling the number of absorption type water chillers and hot water machines in operation according to the air conditioning load, and controlling the opening degree of the capacity control valve of the chiller and hot water machine. A device for controlling operating capacity, comprising: a detection means for detecting that any of the cold/hot water machines is started in standalone operation and low capacity operation; and a time limit means for maintaining the detected power of the detection means for a certain period of time; and sending means for supplying a low opening signal to the capacity control valve of the chiller/heater which is activated in independent operation and low capacity operation in accordance with the timed output of the timer. Capacity control device.