JPS6226499A - Control of fan driving device for water cooling device - Google Patents

Abstract

PURPOSE:To permit to control the power consumption of a fan so as to minimize it by a method wherein heat exchange is effected between hot-water, flowing down through the inside of the water cooling device, and outside air, being sent into the water cooling device, while the temperature signal of cool water, comming out of the water cooling device, is compared with a set signal. CONSTITUTION:The detecting signal T2 from a cooling water temperature detector 12 and a predetermined set signal T0 are impressed on a comparator 14, and outputted deviation signal 15 is routed through a proportional controller 16 and PI controller meter 17 and its output signal 18 from the controller 17 is impressed on a speed changing stage changeover control circuit 19 as an adding control signal 23. Thus, the speed changing stage of a multi-stage speed change gear 5, driving the fan 3, is changed over from a low-speed stage into a high-speed stage as the difference between the cooling water temperature detecting signal T2 and the set signal T0 becomes larger, whereby the driving power of the fan 3 can be minimized and the cooling water temperature can be maintained automatically at a predetermined value at all times.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for controlling a fan drive device for a chilled water device, and in particular, to a method for controlling a fan drive device for a chilled water device, and in particular, a method for constantly maintaining the temperature of chilled water from a chilled water device near a predetermined value that is the minimum necessary value. This invention relates to a method for controlling a fan and drive device for chilled water equipment, which controls the rotational speed of the fan, for example, in oil refineries, petrochemical plants, power plants, etc., where a large amount of cooling water is used. It is advantageously applied in plants.

[Conventional technology]

This type of water chiller is generally a vertical tower.
It has the shape of a lattice filled with wood, etc. of appropriate material, size, and shape, and a fan is installed above the lattice to suck in the atmosphere. Heat-containing hot water is supplied from the upper part of the packing and flows down the tower-shaped water chiller after passing through a certain predetermined plant. This warm water is then brought into countercurrent contact with the atmosphere sucked in by the fan, thereby achieving the required cooling.

By the way, the temperature of the cold water discharged from such a chiller is not only the temperature of the hot water supplied to it, but also
It fluctuates greatly under the influence of the temperature and humidity of the air used for cooling.

For this reason, conventionally, taking this variation into account, the worst weather conditions at the location where the chilled water device is installed were used as a standard, and a margin was provided for the operating capacity, etc.

[Problem that the invention seeks to solve]

As mentioned above, conventional water chillers of this type were designed and manufactured to have sufficient operating capacity, so when the atmospheric temperature is low and the humidity is low, such as in winter, However, there was a problem in that more cooling than necessary was required, and power was wasted accordingly.

This invention was made in order to solve the above-mentioned problems, and the temperature of the cold water from the water chiller is always maintained near a certain predetermined value, and the rotation speed of the fan is appropriately controlled. The object of the present invention is to provide a method for controlling a fan drive device for a chilled water device, which adjusts the amount of cooling air to an appropriate amount and minimizes the power consumption of the fan. It is something.

[Means and effects for solving the problem] A method for controlling a fan for a chilled water device and a drive device according to the present invention is such that the heat-containing hot water flowing down inside the chilled water device and the gear shift are controlled by, for example, a gear shift control circuit. Heat exchange is performed with the atmosphere forced into the chilled water device by a multi-speed variable speed fan driven by a controlled multi-speed gear device, and the temperature of the chilled water flowing out from the chilled water device is The rotational speed of the fan is switched by determining the gear stage of the multi-speed gear device depending on the comparison result between the signal related to the above-described signal and a signal set separately, and the rotational speed of the fan is switched. When the gears are installed, the rotational speeds of the corresponding fans are changed in the same order as when increasing speed and when decelerating the gears of the multi-speed gear device. .

〔Example〕

FIG. 1 is a detailed illustration of the invention when the water chiller is a single unit. In FIG. 1, a packed bed 2 is installed in the middle of a water chiller 1, and a fan 3 for sucking air for cooling is installed above the packed bed 2, which is driven by an electric motor 4 through a multi-gear transmission 5. In addition, a receiving tank 7 is provided at the bottom to accommodate cold water. 10 is a plant, and hot water that has been circulated through the plant and contains heat is cooled in the chiller 1 via a pipe 6, and this cooling water passes from a receiving tank 7 through a pipe 9 and is pressurized by a pump 8. Then, the process returns to the plant 10 and the operations described above are repeated.

If we look at the multi-speed gear device 5 provided between the electric motor 4 and the fan 3 in this case, it is equipped with a speed change gear and a clutch for engaging and disengaging in a number corresponding to the number of gears. However, it is also possible to make the lowest speed gear a freewheel and connect it directly to the output shaft of the chamber@machine.
The latter option has the advantage of simplifying the configuration of the drive device and reducing its cost.

# Oi b K T 1i12 OCORBl Ol
! ;! Let us take as an example a case in which a multi-speed gear device whose lowest speed gear is driven by a freewheel is used.

A control circuit for implementing the method according to the embodiment of the present invention is configured as follows. Comparators 14, 20, proportional controller 16 and P-control controller 17 connected in series with comparator 14, adder 22, signal setting sections 24, 25, 26, comparators 27, 28, 29, AND gate 38, Relay circuit 3
5 and solenoid valves 37, 40, 42, a gear change control circuit 19, signal setting sections 24, 25, 26, comparators 27, 28, 29, and an AND gate 38. Next, the operation of this device will be explained. A detection signal T2 from a cold water temperature detector 12 installed in a pipe 9 for supplying cold water is applied to the (+) terminal of a comparator 14, while a predetermined setting signal T is applied. is applied to one terminal, and the deviation signal 15 output from this is applied to the proportional controller 16. The output from the proportional controller 16 is added to the proportional controller 17, and
Output signal 18 is changed. On the other hand, a detection signal T from the hot water temperature detector 11 installed in the piping B that supplies hot water
.

is applied to the (+) terminal of the comparator 20, and also at the predetermined setting signal. is applied to its (-) terminal, and a deviation signal 21 is output. The output signal 18 from the PI controller 17 is applied to the (upper terminal) of the adder 22, and the output signal 18 from the PI controller 17 is applied to the other (upper terminal). is the one to which the deviation signal 21 is applied, but when only the comparator 14 is operating, the output signal 18 is directly used as an adjustment signal to the gear change control circuit 19; When the comparator 20 is also operating, the sum of the output signal 18 and the deviation signal 21 is used as the adjustment signal.If the comparator 20 is also operating as in the latter case, , although temperature fluctuations of the hot water discharged from the plant 10 are quickly detected and the responsiveness of the gear shift control circuit 19 is improved, in the following explanation, the comparator 20 does not operate. will be explained using an example.

When the additive adjustment signal 26, which is equivalent to the output signal 18, is applied to the gear shift control circuit 19, it is compared with a predetermined setting signal by one of the comparators 27, 28, 29. Now, assuming that the magnitude of the addition adjustment signal 23 is between the low speed setting signal 24 and the medium speed setting signal 25, the comparator 2
7 becomes positive and the remaining comparators 28.
The output signals 31.52 from 29 are both negative. Therefore, only the output signal 30 passes through the diode 27A and becomes H.
A signal 34 is applied to the relay circuit 35 to activate the corresponding solenoid valve 37. Then, the switch of the electric motor 4 is turned on, and the rotational operation is started.
The power is transmitted to the fan B via the wheel shaft, causing it to rotate at a low speed. Next, when the magnitude of the addition adjustment signal 23 shifts between the medium speed setting signal 25 and the high speed setting signal 26, the output signal 31 from the comparator 28 becomes positive, and the output from the remaining comparator 29 Signal 32 goes negative.

At this time, the AN provided after the comparator 28
When the logic condition of the D gate 38 is established, the corresponding solenoid valve 4
0 is activated. As a result, the middle speed clutch is engaged, and the rotational operation of the electric motor 4 is transmitted to the fan B via the middle speed clutch of the multi-speed gear device 5, so that the fan B rotates at a medium speed. When this medium-speed rotation is performed, the freewheel for low-speed rotation idles, and the transmission of the low-speed rotation to the fan 3 is cut off. Next, when the magnitude of the addition adjustment signal 23 exceeds the magnitude of the high speed setting signal 26, the output signal 6 from the comparator 29
2 becomes positive, the solenoid valve 42 is activated via the relay circuit 35, the high-speed clutch is engaged, and the motor 40 rotates while high-speed transmission is performed via the high-speed clutch of the multi-speed gear device 5. , the logical condition of the AND gate 38 is not satisfied, and the solenoid valve 4 corresponding to medium speed rotation operation
0 is opened, and the middle speed clutch is disengaged.

In this way, the cold water temperature detection signal T2 and the predetermined setting signal T. As the difference between Control is automatically performed to minimize the amount of power required for cooling, and to maintain the temperature of the chilled water near a certain predetermined value at all times. Note that the cold water temperature detection signal T2 and setting signal T mentioned above. When the difference between the two becomes smaller, the gear position in the multi-speed gear device 5 is changed from the high speed position to the middle speed position and then to the low speed position.

FIG. 2 is a detailed explanatory diagram of the present invention when three chilled water devices are installed in parallel. In this FIG. 2, FIG. 2 (aJ is an overall schematic configuration diagram, and FIG. 2 (b) is a logical function explanatory diagram of the gear shift control circuit +9A.

First, looking at Figure 2 (a), the same reference numerals as in Figure 1 indicate the same or equivalent parts, and the three water chillers and their associated equipment. For example, the symbols 1a, 2b, etc. are given by adding a, b, and C to the symbols in FIG. 1.

44 is a mixing tank, each cooling water device +a, 1b and 1
It accommodates the intermediate cold water flowing down from the lower receiving tanks 7a, 7b and 7C. 45° 46 and 47 are both intermediate chilled water temperature detectors, and are respectively connected to the chilled water device 1.
Comparators 48, 49, and 50, which will be described later, are provided corresponding to a, jb, and 1c, and a predetermined setting signal T is input.

A comparison is made with Now, the intermediate cold water temperature detector 4
The detection signals from T3.5.46 and T3.5.47 respectively. T,
' and T6°. These signals are processed in the comparators 48, 49 and 50 described above, respectively.
Setting signal T. and the resulting output is applied as correction signals 51, 52 and 53 to adder 22A, output signal 18 from comparator 14 and comparator 20
is added with the deviation signal 21 from
5 and is added to the gear shift control circuit 19A. In this way, the response to the temperature change of the intermediate chilled water corresponding to each chilled water device can be made quickly, but in the following explanation, the case where only the comparator 14 is operated will be taken as an example. At this time, the signal input to the comparator 14 is a certain predetermined setting signal T. , and a signal T2 regarding the temperature of the cold water taken out from the mixing tank 44.

Next, the gear change control circuit 19A illustrated in FIG. 2(b) will be explained. Nine comparison circuits 66 to 74 are provided at the input stage. Now adder 22
It is assumed that an addition adjustment signal 55, which is an output signal from A, is added.

Then, this addition adjustment signal 55 tends to increase, and the first
Higher than the set value 57 and lower than the second set value 58, the output of the comparator 66 will be positive and the positive pulse produced by the capacitor 89 will then cause the diode 90 to conduct and voltage) is applied to a first counter 87 as a pulse signal 85. Next, if the addition adjustment signal 55 increases and becomes higher than the second set value 58 and lower than the third set value 59, the output of the comparator 67 becomes positive, and accordingly the output H pulse 8
5 is added to the first counter 87. Thereafter, in the same way, the addition adjustment signal 55 further increases, and each time it exceeds the set value corresponding to each of the nine comparators 66 to 74, an H pulse is output, and these pulses are equal to the first one. counter 8
7 will be added sequentially. On the other hand, the addition adjustment signal 55 has a decreasing tendency in the gear shift control circuit 19A.
is applied, a pulse 86 of L (0 or low voltage) is outputted from the ratio controller that satisfies the comparison condition and is added to the second counter 88.

The first and second counters 87 and 88 are both so-called ternary counters, and the former counts every three times the H pulse increases, and the latter counts every three times the L pulse increases. Each of them is reset to its original state. Among the comparators 66 to 74, three of the first group correspond to low speed control, six of the second group correspond to medium speed control, and six of the third group correspond to high speed control. A converter 91 is provided before the first group, a comparator 131 is provided before the second group, and a comparator 132 is provided before the third group. 133, a middle gear start signal 164 and a high gear start signal 135 are made available.

The three types of start signals 133, 134 and 165 described above are the count signal 1 from the first counter 87.
25, 126, 101 and the count signals 127, 128° 116 from the second counter 88 are applied to the digital control circuit 166 to control the water chiller +a, 1b.
and generates an activation signal for gear change control for 1C. First, the six types of start signals 433, 134
and 135 are the AND gates 137 of 91, respectively.
-145 are branched and input. Among them, the first group of AND gates 137, 138, and 439 are used to give initial signals for the low speed stage, middle speed stage, and high speed stage to the water chiller 1a. Similarly, the second group A
The ND gates 140 to 142 correspond to the chilled water device 1b, and the second group of AND gates 143 to 145 correspond to the chilled water device 1C.

Then, the first group of AND gates 157°438.
Initial signals 146, 147 and 148 for low, medium and high speed stages from 139 are applied to AND gates 155, 156 and 157, respectively, and count signals from first and second counters 87, 8B 125,127
A predetermined intermediate signal for the chilled water device 1a is output when the logical condition between the two is satisfied. Also, similar initial signals 149, 150 and 151 from the second group of AND gates 140, 141 and 142 are, respectively,
AND game) added to 158, 159 and 160,
Count signal 1 from first and second counters 87 and 88
When the logical condition between 26 and 128 is satisfied,
An intermediate signal for the water chiller 1b is issued. And the AND gates 143, 144 and 1 of the sixth group
Similar initial signals 152, 153 and 154 from 45
are AND gates 161, 162 and 166, respectively.
When a logical condition is established between the count signals 101 and i16 from the first and second counters 87 and 88, an intermediate signal for the chilled water device 1c is output.

Intermediate signals 164-172 outputted from AND gates 155-163, respectively, are connected to RS slip 70 knobs 173-173 provided correspondingly and operating as self-holding circuits.
181 and outputs an activation signal from its output terminal Q, which is held until a reset signal is applied to the reset input terminal k. Also, the second
Count signals 127, 128 and 116 in counter 88 are connected to AND gates 182 and 183, respectively.
and 1,84, the above-mentioned initial Vt in the middle speed gear=
147, 150 and 156 is taken, and the resulting output signals 185, 186
and 187 are used as reset signals for low speed RS flip-flops 173, 176 and 179, respectively. Next, the count signals 127, 128 and 116 in the second counter 88 are respectively A
In the ND gates 188, 189 and 190, the above-mentioned initial signals 148, 15+ and 15 at the high speed stage are
4 and the resulting output signals 191, 192 and 196 are used as reset signals for medium speed RS flip-flops 174, 177 and 180, respectively. Furthermore, the second
Count signals 127, 128 and 116 in counter 88 are passed through inverters 194, 195 and 195, respectively, to high-speed flip-flops 175, 1
Used as a reset signal for 78 and 181.

Low speed RS flip-flops 473, 176 and 17
From the respective output terminals Q of 9, low speed stage operation signals 203, 20 corresponding to the chilled water devices +a, 1b and 1c are output.
4 and 205 are output. The outputs from the respective output terminals Q of medium-speed RS flip-flops +74, 177, and 180 are applied to ANp gates 206, 207, and 208, and are applied to the corresponding high-speed RS flip-flops 175, 178, and 181, respectively. An AND condition is taken with the output from the output terminal Q, and depending on the result, the operating signals 209, 210 and 211 for the middle gear are output. Similarly, high-speed stage activation signals 212, 213 and 214 are output from output terminals Q of high-speed RS flip-flops 175, 178 and 181, respectively.

The operation of the gear change control circuit 19A as described above will be explained below. Now, assuming that the entire system including the plant 10 is started and the addition adjustment signal 55 is input via the adder 22A, and that this is lower than the first stage setting signal 57, the low speed stage start signal 133
are applied as H signals to the H active input terminals of AND gates 137 to 145, while medium speed start signal 164 and high speed start signal 135 are applied to the corresponding comparators 13
Since the H signals from 1 and 132 are not output, their output signals remain at L. Therefore, for the medium speed start signal 134 and the high speed start signal 165, an AND gate 137, 140 having an L active input terminal is used.
and 143 output low speed initial signals 146, 149 and 152 corresponding to each chilled water device 1a, 1b and 1C, respectively.

Next, when the addition adjustment signal 55 increases and exceeds the first stage setting signal 57, the output of the comparator 66 changes from negative to positive.
An H pulse signal 85 is output via a capacitor 89 and a diode 90.

This H pulse signal 85 is given to a first counter 87 that counts H pulses, outputs a count signal 125 of the first H pulse, and inputs an H input signal to the H active input terminals of AND gates 155, 156, and 157. give. On the other hand, if the first count signal from the second counter 8q that counts the L pulses input to the negative active input terminals of these AND gates 155, 156, and 157 is in the L state, it is input to the AND gate 155. Since only the initial signal 146 that is active is HK7Z, the intermediate signal 164 of the L active output is applied from this AND gate 155 alone to the GO terminal of the RS flip-flop 1730, and the positive activation signal 203 is output from its Q terminal. , relay circuit 35A
Then, the solenoid valve 216 is operated, the switch of the electric motor 4a corresponding to the chilled water device 1a is turned on, and the rotational motion is transmitted to the fan 3a via the low speed freewheel in the speed change control device Sa.

Then, the addition adjustment signal 55 continues to increase,
When the second stage comparator 67 outputs the H pulse signal, the second H pulse count signal 126 is output,
Similarly to the above case, the AND gate 158 receiving the H active signal from the AND gate 140 becomes the L active state, inputs the future output signal 167 to the hundred terminal of the hundred flip-flop 176, and inputs the output signal 167 to the hundred terminal of the hundred flip-flop 176, The solenoid valve 219 is actuated by the H output signal 204, the electric ji4b of the water chiller 1b is turned on, and the low-speed rotation operation is transmitted to the fan 6b. Furthermore, the sixth stage comparator 6
When the H pulse signal is output from 8, the third count signal 101 becomes H, and the AND gate 161 similarly becomes the L active state, the solenoid valve 222 is operated, and the switch of the electric motor 4C of the water chiller 1C is turned on. The fan 3C is turned on, and the low speed rotation operation is transmitted to the fan 3C. By the way, 3
When the th count signal 101 is output, this signal 101 is applied to the multi-by-breaks 102' and 103, and the count signal 99. is output from the AND gates 96, 97 and 98. IDO and 101 become L and the single power signals of RS flip-flops 173, 176 and 179 which are in the active state become HK, but the low power terminal is
Unless a signal is input, the output from the Q terminal of each i) flip-flop is self-held at H.

Under such a state, when the addition adjustment signal 55 decreases in the opposite way, the comparison signal 77 from the comparator 68 changes from positive to negative, and from this, the capacitor 89
And the diode 105 outputs an L pulse signal 86. This pulse signal 86 is converted into an H pulse signal through an inverter 106, and then is input to a second counter 8.
8, the count signal 1 of the first H pulse
27 is output. Then, connect L to one L active input terminal.
When the count signal 127 is applied to the H active input terminal of the AND gate 182 which receives the signal 147, the AND gate 182 outputs the L active signal 185 from its L active output terminal, and It is added to the i terminal of the RS flip-flop 173. As a result, the R
The Q output signal 206 from the S flipflop 173 is low.
Therefore, the electric valve 216 is demagnetized, and the electric motor 4a of the chilled water device 1a is turned off.

When the additive adjustment signal 55 continues to decrease and the output signal from the comparator 67 changes from positive to negative, the electric motor 4b of the water chiller 1b is switched off in the same manner as in the case described above, and this decrease occurs. If the operation continues further, the electric motor 4C of the water chiller 1C is turned off.

Although only the case of the low speed gear has been described so far, the same operation is performed in the case of the middle speed gear and the high speed gear, and the clutches are engaged and disengaged in a predetermined order.

Next, a description will be given of a switching operation between different gear shifts, for example, a switching operation between a low gear and a middle gear. As described above, when the output signals from the comparators 66 to 68 change from negative to positive, the switch of each electric motor of each chilled water device 1a, 1b, 1c is turned on and low speed rotation operation is transmitted.

Under such a state, as the addition adjustment signal 55 increases, the medium speed start output signal 134 of the comparator 161 becomes H, and the initial signals 147, 150 for the medium speed stage of each chiller.
and 153 to H, AND gate 138,
141 and 144. Next, when the output signal of the first stage comparator 69 for the middle speed gear changes to positive, the H pulse signal 85 is output to the first counter 87, and the first H pulse count signal 125 is ANDed. gate 155,
156 and 157. As a result, since only the A N D gate 156 accepts the initial signal 147, it becomes active and outputs the L signal 165 to the πg flip-flop 1740g terminal, and accordingly, the H signal is ANDed from the Q terminal. Output to gate 206. This A
Since the L signal 212 is input to the L active input terminal of the ND gate 206, the H operation signal 209 for the middle speed stage is output, and accordingly, the chiller 1a changes from the low speed stage to the middle speed stage. It will be switched in stages. Under these conditions, contrary to the previous case, the addition adjustment signal 55 decreases, the pulse signal from the comparator 69 changes from H to L, and the H pulse count signal 1 from the second counter 88 changes.
27 is input to the A N D gate 188, this A
From the ND gate 188, an L active signal is applied to the terminal of the RS clip flop 174, resulting in a Q
The output becomes L and the middle speed clutch is disengaged. On the other hand, the π100 flip-flop 176, which was in a self-holding state, outputs an H signal from its Q terminal, and by restarting transmission of low-speed rotation, a changeover from the middle speed gear to the low speed gear is performed. Switching between medium and high gears is also operated in a similar manner.

In addition, although the above-mentioned example explained the case where a digital circuit was used as a control device, it is not limited to this.
For example, a program control circuit combined with a suitable microcomputer can be advantageously applied.

〔Effect of the invention〕

As explained above, according to the method of the present invention, heat exchange is performed between the heat-containing hot water that is passed through the chiller and the atmosphere that is forcibly fed into the chiller by a multi-speed variable fan. When this is done, the rotational speed of the fan is switched depending on the comparison result between a signal related to the temperature of the chilled water output from the chiller and a separately set signal. The temperature of the chilled water from the chiller can be maintained near the optimum value without consuming significant power.

Furthermore, when a plurality of the chilled water devices are installed in parallel,
By making the switching order of the corresponding fan rotational speeds the same during speed increase and deceleration, the loads placed on these devices are averaged out.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an apparatus to which an embodiment method of the present invention can be applied, and FIG. 2 is a block diagram of an apparatus to which a different embodiment method of the invention can be applied. 1.1a~1c---Chilled water system, 6,3a~3C---Fan, 5,5a~5C---Multi-speed gear device, 10---Plant, 14---Comparator, 19.19A---Shift stage switching Control circuit, 22, 22A... Adder, 35.35A...
relay circuit. In each figure, the same reference numerals indicate the same or corresponding parts. Continued on page 1 5 Inventor Ryu Hiko Tanie 405 Shimojobo, Oaza, Kamo City

Claims (5)

[Claims] (1) Chilled water that undergoes heat exchange between the heat-containing hot water flowing down the chilled water device and the atmosphere that is forcibly fed into the chilled water device by a multi-speed variable speed fan pivoted by a multi-speed gear device. A method for controlling a fan drive device for an apparatus, wherein a signal related to the temperature of cold water outputted from the chilled water device is compared with a separately set signal, and the multi-speed gear device is controlled depending on the comparison result. A method of controlling a fan lowering device for a chilled water device, in which the rotational speed of the fan is changed by determining a gear stage. (2) A patent claim in which a comparison result between a signal regarding the temperature of the heat-containing hot water flowing down in the chilled water device and the separately set signal is used in combination to determine the gear stage of the multi-speed gear device. A method for controlling a fan drive device for a chilled water device according to scope 1. (3) A fan drive device for a chilled water device according to claim 1, wherein a plurality of the chilled water devices are arranged in parallel, and the gear speeds of the multi-speed variable fans corresponding to the respective chilled water devices are changed in a predetermined order. Control method. (4) The method for controlling a fan drive device for a chilled water device according to claim 3, wherein the gear stage is changed sequentially. (5) The method for controlling a fan and drive device for a chilled water device according to claim 3, wherein the speed change is performed in the same order as the speed increase and deceleration.