JP2001265445A - Three position control method and three position controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three position control method and a three position controller capable of suppressing running costs and improving control precision. SOLUTION: At the time of holding controlled variables around a set value Tk by a controlled variable increasing means 60 for increasing the controlled variables and a controlled variable decreasing means 70 for decreasing the controlled variables, an upper control target value Tc for controlling the controlled variable decreasing means 70 is set at a prescribed position above the set value Tk, and a lower control target value Th for controlling the controlled variable increasing means 60 is set at a prescribed position below the set value Tk, and correction processing for bringing the control target value used for calculating deviation Td between the controlled variables and the control target value closer to the set value Tk is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a three-position control method and a three-position control device. More specifically, the present invention relates to a three-position control method and a three-position control device for controlling, for example, a room temperature at a set temperature.

[0002]

2. Description of the Related Art Conventionally, when a room temperature is controlled to a target value by a heating device (heater) and a cooling device (cooler), there is a time delay in the temperature control by the cooling device.
In addition, since the control accuracy cannot be ensured due to the difficulty of the control, the heating device is appropriately operated while the cooling device is continuously operated.

[0003] However, in such a conventional control method, since the cooling device is constantly operated and the heating device performs heating while cooling by the cooling device, energy efficiency is large due to large energy loss. There is a disadvantage that it is bad.

[0004] To solve the above-mentioned disadvantages, a two-position control method and a three-position control method have been proposed.

In the two-position control method, as shown in FIG. 8, the heating device is activated when the detected value _{Tpr of the} room temperature to be controlled falls below the set temperature _Tpk , and the cooling device is activated when the temperature exceeds the set temperature _Tpk. By operating, the room temperature is controlled to be kept near the set value. Such a two-position control method can accurately control the temperature near the set temperature, but has a problem that the running cost is still high because the heating device or the cooling device must always be operated.

In the three-position control method, as shown in FIG. 9, a cooling control target value T higher than a set temperature T _pk by a predetermined temperature is used.
While setting _pc , the heating control target value _Tph is set lower by a predetermined temperature than the set temperature _Tpk . And the room temperature T
_{If pr} is to remain at lower than the set temperature T _pk is a turn on the heating device indoor temperature T _pr is below the heating control target value T _ph, indoor temperature T _pr is above the heating control target value T _ph heating The operation of turning off the device is repeated. When the room temperature T _pr is higher than the set temperature T _pk ,
When the room temperature _Tpr exceeds the cooling control target value _Tpc , the cooling device is turned on, and when the room temperature _Tpr falls below the cooling control target value _Tpc , the cooling device is turned off.

The three-position control method has an advantage that the running cost can be suppressed as compared with the two-position control method because the indoor temperature is controlled by turning on or off one of the heating device and the cooling device. . However, since the room temperature is controlled not near the set temperature but near the cooling control target value or the heating control target value, there is a problem that the control cannot be performed at the set temperature and the control accuracy is poor.

As an attempt to solve such disadvantages of the conventional two-position control method and three-position control method, Japanese Patent Application Laid-Open No. 8-54901 proposes a load selection control method. In this method, as shown in FIG. 10, the heating device is turned on when the room temperature _Tpr falls below, for example, the heating control target value _Tph , and once the heating device is turned on, the room temperature _Tpr becomes the set temperature. When the temperature exceeds T _pk , the heating device is turned off. When the room temperature T _pr falls below the set temperature T _pk , the heating device is turned on. Also, the room temperature T _pr
Is greater than the cooling control target value T _pc , the cooling device is turned on. Once the cooling device is turned on, when the room temperature T _pr falls below the set temperature T _pk , the cooling device is turned off and the room temperature T _pr is turned off.
Is higher than the set temperature _Tpk , the cooling device is turned on.

In this load selection control method, the control temperature can be controlled relatively accurately in the vicinity of the set temperature in the steady state, and the temperature is controlled by turning on or off only one of the heating device and the cooling device. Therefore, there is an advantage that an increase in running cost can be suppressed.

However, in the load selection control method, when switching between the control by turning on and off the heating device and the control by turning on and off the cooling device (see point G in FIG. 10), the control deviation is large, and the load is not controlled in a steady state. However, there is a problem that the control accuracy may be deteriorated.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and has a three-position control method and a three-position control method capable of suppressing running costs and improving control accuracy. It is intended to provide a position control device.

[0012]

According to the three-position control method of the present invention, the control amount is held around a set value by a control amount increasing means for increasing the control amount and a control amount lowering means for decreasing the control amount. A three-position control method, wherein an upper control target value for controlling the control amount lowering means is set at a predetermined position above the set value, and the control amount increasing means is set at a predetermined position below the set value. Setting a lower control target value for controlling the control amount, and using a deviation between the control amount and the control target value, performing a correction process to bring the control target value used when calculating the deviation closer to the set value. It is characterized by.

In the three-position control method of the present invention, when the control amount suddenly changes and exceeds the upper limit value, the upper control target value is forcibly set as the initial upper control target value, and the control amount changes rapidly and the lower limit value is set. If it exceeds, it is preferable that the lower control target value is forcibly set as the initial lower control target value.

On the other hand, according to a first embodiment of the three-position control device of the present invention, the control amount is held around a set value by a control amount increasing means for increasing the control amount and a control amount lowering means for decreasing the control amount. A three-position control device, wherein the three-position control device has a control unit and a target value correction unit, and the control unit can control the control amount lowering unit by an upper control target value. The control amount raising means can be controlled by the lower control target value, and the target value correction means uses the deviation between the control amount and the control target value to calculate the deviation. A correction process for bringing the control target value closer to the set value is performed.

In a second embodiment of the three-position control device according to the present invention, the control amount is raised around a set value by a control amount raising means for raising the control amount and a control amount lowering means for lowering the control amount. A three-position control device, wherein the three-position control device has a control unit, a target value correction unit, and a target value forcible change unit, and the control unit decreases the control amount by an upper control target value. Means can be controlled, and the control amount increasing means can be controlled by a lower control target value, and the target value correction means uses the deviation between the control amount and the control target value to calculate the same deviation. Correction processing for bringing the control target value used at the time of calculation closer to the set value is enabled, and the target value forcible changing means forcibly sets the control target value when the control amount reaches a preset limit value. To initial value Characterized by comprising been the ability.

[0016]

Since the present invention is constructed as described above, the control amount raising means and the control amount lowering means can be controlled in the vicinity of the set value, and can be controlled when the control amount raising means and the control amount lowering means are switched. There is no risk of disturbance. Further, according to the preferred embodiment of the present invention, even when a sudden change occurs in the control amount, the influence thereof can be minimized.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments with reference to the attached drawings, but the present invention is not limited to only such embodiments.

Embodiment 1 FIG. 1 shows a schematic configuration of a temperature control system to which a three-position control method according to Embodiment 1 of the present invention is applied, and FIG. 2 shows a schematic flowchart of the temperature control system.

The temperature control system 10 is a temperature management system for controlling the room temperature _Tr as a control amount so as to maintain the room temperature _Tr at a set value _Tk , and includes a set value _Tk , a cooling control target value (an upper control target value). ) T _c , heating control target value (lower control target value) _Th , upper limit value T _U , lower limit value _TL , capacity of heating / cooling source (heat quantity), that is, capacity of heating device 60 and cooling device 70 and room temperature T _An input unit 20 for inputting an integration coefficient n and the like set in accordance with a balance with a change amount (heat amount) of _r.
If a detection unit 30 having a temperature sensor for measuring the room temperature T _r, the control unit 40 for controlling to keep the indoor temperature T _r, which is measured by the detector 30 to a set value T _k, the control unit 4
A drive unit 50 for driving a heating device (heating means, control amount increasing means) 60 and a cooling device (cooling means, control amount decreasing means) 70 in accordance with the control result of 0 is provided.

[0020] Here, the integrated coefficient n is, for example, 10, to a predetermined temperature T ₁ of a value higher than the cooling control target value T _c set value T _k, the heating control target value T _h is a predetermined temperature than the set value T _k T
Set to _two lower values respectively. The upper limit value T _U is generally set to a value higher than the cooling control target value T _c by a predetermined temperature T ₃ ,
The lower limit T _L is typically set respectively to a predetermined temperature T ₄ lower than the heating control target value T _h. However, the upper limit value T _U
May have been in to match the cooling control target value T _c, the lower limit T _L may have been matched to the heating control target value T _h.

The control unit 40 is similar to the ordinary three-position control.
Then, a heating device (heating
Means) 60 and a cooling device (cooling means) 70
For example to activate or deactivate, i.e.
Control means 41 for controlling the temperature and the measured room temperature T_rTo
Whether there is a sudden change, that is, the room temperature T_rIs the upper limit T_UMa
Or lower limit T_LDetermining means 42 for determining whether or not
And the measured room temperature T_rIf there is no sudden change in
The heating device 60 and the cooling device 70 are turned on and off, respectively.
Heating control target value T that functions as a threshold_hand
Cooling control target value T_cIs the measured room temperature T_rIn response to the
A target value correcting means 43 for correcting the temperature and the measured room temperature T
_r, The heating control target value T_hAnd cooling system
Goal value T _cTarget value compulsory change to the initial value
Further means 44.

Next, the control contents of the temperature control system 10 will be described with reference to FIG.

First, the initial set value T _k0 of the room temperature, the target value T _{h0 of} the initial heating control, the target value T _{c0 of} the initial cooling control, and the upper limit value T
_U , lower limit value _TL , integration coefficient n, etc. are set (step S
1). Next, the indoor temperature _Tr is measured (step S).
2). The measured room temperature _Tr is sent to the control means 41 and the determination means 42. The control means 41 controls the heating device 60 and the cooling device 7 based on the input room temperature _Tr.
0 is turned on and off (step S3). The determining means 42 determines whether or not the input room temperature _Tr has changed abruptly (step S4). If there is no sudden change in the room temperature _Tr , a target value correction process is performed by the target value correction means 43 (step S5). On the other hand, if there is a sudden change in the room temperature _Tr , the control target value is forcibly changed by the target value forcible changing means 44 (step S6).

Hereinafter, the processing in each of the means 41, 43, and 44 will be described more specifically.

First, referring to FIG.
Will be described.

The processing in the control means 41 is repeatedly executed every predetermined time (for example, 1000 ms).

In the process by the control means 41, as shown in FIG. 3, it is determined whether or not the measured room temperature _Tr is higher than the cooling control target value _Tc (step S11). If it is higher, it is determined whether the heating device (heater) 60 is off (step S12). If it is not off, it is turned off (step S13). If it is off, the cooling device (cooler) 70 is on without any change. Is determined (step S
14). If the cooling device 70 is not on, it is turned on (step S15), and if it is on, the process returns to the start in that state.

[0028] In the step S11, if the indoor temperature T _r is less than the cooling control target value T _c is further room temperature T _r is determined whether less than the heating control target value T _h (step S16). If it is low, it is determined whether the heating device 60 is on (step S17). If it is off, it is turned on (step S18). If it is on, it is determined whether the cooling device 70 is off without any change. Judgment (Step S1
9). If the cooling device 70 is not turned off, it is turned off (step S20), and if it is off, the process returns to the start in that state.

[0029] In the step S16, if the indoor temperature T _r is higher than the heating control target value T _h, the heating device 60 determines whether the off (step S21), and turns off if it is not turned off (step S22 If it is off, it is determined whether or not the cooling device 70 is off as it is (step S23). If the cooling device 70 is not off, it is turned off (step S24), and if it is off, the process returns to the start in that state.

[0030] Thus, at a temperature range higher than the cooling control target value T _c is the cooling apparatus 70 is turned on, the heating device 60 is turned on at a lower temperature region than the heating control target value T _h, heating and cooling control target value T _c In the temperature range between the control target value _Th and the normal three-position control process in which both the cooling device 70 and the heating device 60 are turned off.

Next, the process of correcting the control target value by the target value correcting means 43 will be described with reference to FIG.

[0032] In the correction processing of the control target value, first determines the measured indoor temperature T _r is whether higher than the set value T _k (step S31). By subtracting the T _k values from T _r value is higher, it calculates the deviation T _d between the set value T _k and the room temperature T _r (step S32), processing, for example, dividing the T _d value by integrating factor n Or multiply (step S3
3) The current correction value T _ds is calculated, the calculated T _ds value is subtracted from the cooling control target value T _c , the result of the subtraction is newly set as the T _c value (step S34), and the process returns to the start.

In step S31, the room temperature _{Tr is determined.}
If There is less than the set value T _k, by subtracting T _r values from T _k value to calculate the deviation T _d between the set value T _k and the room temperature T _r (step S35), the T _d value Calculation processing, for example, division or multiplication by the integration coefficient n (step S3
6), the current correction value T _ds was calculated by adding the calculated T _ds value in heating control target value T _h, newly T _h this addition result
The value is set as a value (step S37), and the process returns to the start.
Note that the division or multiplication in the arithmetic processing is appropriately selected according to the value of the integration coefficient n.
In the case of 0, while division is performed, the integration coefficient n is 0.1
Is multiplied. However, in general, since the capacity (heat amount) of the heating / cooling source, that is, the capacity of the heating device 60 and the cooling device 70 is larger than the room temperature change amount (heat amount), the integration coefficient n is set to be divided.

[0034] In the process according to FIG. 4, when the indoor temperature T _r in the step S31 is determined to not more than the set value T _k, which is corrected in accordance with heating control target value T _h to the deviation T _d and was, but due the state of the environment, without the heating and cooling control on the object, if the indoor temperature T _r is kept to the set value T _k, step without this correction process S3
The processing of steps S5 to S37 may be skipped, and the process may return to step S31. This eliminates the need to operate the heating device 60 and the cooling device 70, and has the advantage that unnecessary power is not used.

[0035] By the above processing, on the room temperature T _r is cooling device 70, in a state of being controlled by off gradually approaches the set value T _k at a rate cooling control target value T _c is in accordance with the integrated coefficient n , to follow it even indoor temperature T _r, on the cooling device 70 in the vicinity of the set value T _k, it is controlled by off.

On the other hand, on the room temperature T _r is the heating device 60, in a state of being controlled by off gradually approaches the set value T _k at a rate heating control target value T _h is in accordance with the integrated coefficient n, the room temperature T _r even follow it, on the heating device 60 in the vicinity of the set value T _k, it is controlled by off.

[0037] That is, as shown in FIG. 5, the indoor temperature T _r
On the but cooling device 70, gradually descends room temperature T _r as the cause and lowering of the ambient temperature in a state of being controlled by the off, when below the heating control target value T _h, the heating control target value T _h ON of the heating device 60 with the reference value as
Heating control target value T _h with control of the room temperature T _r is initiated by off gradually approaches the set value T _k. At this time, the cooling control target value _{Tc is changed} to the initial cooling control target value _Tc0.
To the heating control target value _Th and the cooling control target value _Tc.
It is preferable to control so as to keep the interval between them constant.

Similarly, in a state where the room temperature _Tr is controlled by turning on and off the heating device 60, the room temperature _Tr gradually increases due to an increase in ambient temperature or the like, and the cooling control target value _Tc is reduced. When the temperature exceeds the cooling control target value _Tc , the room temperature T due to the turning on and off of the cooling device 70 with the cooling control target value _Tc as the reference value
cooling control target value T _c with the control is started _r is gradually approaches the set value T _k. At this time, the heating control target value T _h to control to keep the interval between the reset to the initial heating control target value T _h0 and heating control target value T _h and the cooling control target value T _c is preferred.

Thus, the room temperature _Tr is always set to the set value _Tk.
It is possible to hold it around. Next, the process of forcibly changing the control target value by the target value forcible changing means 44 will be described with reference to FIG.

First, the measured room temperature T_rIs the upper limit T_U
Is determined (step S41). Room
Internal temperature T_rIs the upper limit T_UExceeds the control target value.
Period cooling control target value T_c0(Step S
42). On the other hand, the room temperature T_rIs the upper limit T_UMust not exceed
Then, the control target value is set to the initial heating control target value T._h0To force
It is changed (step S43). As a result,
Room temperature T _rSuddenly changes to the upper limit T_UOr lower limit T_L
Room temperature T_rQuickly
Target value T_kCan be approached. In this case,
First measured room temperature T_rIs the lower limit T_LExceeds
It may be determined whether or not this is the case.

[0041] Thus, the temperature control system 10 of the embodiment 1, on the cooling device 70 at the room temperature T _r is higher than the set value T _k states, the cooling control target value T _c which serves as a reference value of the off controlled so as to approach the set value T _k, the indoor temperature T _r is on the heating device 60 is lower than the set value T _k state, the heating control target value T _h which functions as a reference value of the off
Is controlled so as to approach the set value T _k , so that the room temperature _Tr can be controlled with high accuracy and low running cost, and it is possible to suppress the control loss at the time of switching the operation of the cooling device 70 and the heating device 60. , And the room temperature _Tr
Can be promptly dealt with even if an abnormal situation occurs that exceeds the upper limit value T _U or the lower limit value _TL .

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIG. The temperature control system to which the three-position control method according to the second embodiment is applied is different from the first embodiment only in the process of correcting the control target value by the target value correcting means 43. Description is omitted.

The correction processing of the control target value in the second embodiment is repeatedly executed at predetermined time intervals (for example, 1000 ms) as in the first embodiment. That is, first, the set value _Tk is subtracted from the measured room temperature _Tr (step S5).
1), the deviation T _d between the set value T _k and the room temperature T _r is calculated (step S52). This _Td value is subjected to arithmetic processing, for example, division or multiplication by the integration coefficient n (step S5).
3), and calculates a present correction value T _ds, the calculated T _ds values cooling control target value T _c and heating control target value T _h and Karakara subtracted, these subtraction results newly T _c values and respectively T _The value is set as the _h value (step S54), and the process returns to the start.

[0044] That is, if the indoor temperature T _r is the set value T _k above, the cooling device 70 on, together with the cooling control target value T _c which serves as a reference value for turning off gradually approaches the set value T _k , The heating control target value _Th is the cooling control target value _Tc.
Is changed following the cooling control target value _Tc so that the difference from the cooling control target value _Tc does not change.

[0045] Similarly, if the indoor temperature T _r is less than the set value T _k, on the heating device 60, the heating control target value T _h which functions as a reference value for turning off gradually approaches the set value T _k At the same time, the cooling control target value _Tc becomes the heating control target value _Th.
Difference between so as not to change, changes following the heating control target value T _h.

[0046] Thus, the cooling control target value T _c and heating control target value T _h initial value T _c0, T heating control target value and the cooling control target value T _c without performing a reset operation to _h0 T _h of
Can be kept at a predetermined interval.

As described above, the present invention has been described based on the embodiments. However, the present invention is not limited to only the embodiments, and various modifications are possible. For example, in the present embodiment, the control amount is the room temperature. However, the control amount is not limited to the room temperature, and may be various, such as a water temperature.

[0048]

As described above in detail, in the present invention, the control amount is controlled to be maintained at the set value by the operation of the control amount increasing means for increasing the control amount and the control amount lowering means for decreasing the control amount. When turning on, each of the control amount raising means and the control amount lowering means is turned on / off based on the set value.
Since each control target value for switching off is set, and each control target value is corrected according to a deviation between the control amount and the set value, only one of the control amount increasing means and the control amount lowering means is controlled. It is possible to control the control amount in the vicinity of the set value by controlling, for example, switching on and off, thereby achieving an excellent effect that the running cost can be suppressed and the control accuracy can be improved. Play.

Further, according to the preferred embodiment of the present invention, even if a sudden change occurs in the control amount, its influence can be minimized.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a temperature control system to which a three-position control method according to a first embodiment of the present invention is applied.

FIG. 2 is a schematic flowchart of the temperature control system.

FIG. 3 is a flowchart showing a processing procedure by a control unit.

FIG. 4 is a flowchart showing a processing procedure by a target value correction unit.

FIG. 5 is a graph showing a control example of the present temperature control system.

FIG. 6 is a flowchart showing a processing procedure by a target value forcible change unit.

FIG. 7 is a flowchart showing a processing procedure by a target value correction unit of a temperature control system to which a three-position control method according to a second embodiment of the present invention is applied.

FIG. 8 is a graph for explaining conventional two-position control.

FIG. 9 is a graph for explaining conventional three-position control.

FIG. 10 is a graph illustrating an example of a conventional improvement technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Temperature control system 20 Input part 30 Detection part 40 Control part 41 Control means 42 Judgment means 43 Target value correction means 44 Target value compulsory change means 50 Drive part 60 Heating device (heater, heating means, control amount rise means) 70 Cooling device (Cooler, cooling means, control amount lowering means) _Tr Indoor temperature (control amount) _Tk set value _Tc Cooling control target value (upper control target value) _Th Heating control target value (lower control target value) T _U upper limit Value _TL lower limit

Claims (4)

[Claims] A control amount increasing means for increasing the control amount;
A three-position control method for controlling a control amount to be maintained around a set value by a control amount lowering unit for lowering a control amount, the method comprising controlling the control amount lowering unit to a predetermined position above the set value. Setting an upper control target value, setting a lower control target value for controlling the control amount raising means at a predetermined position below the set value, using a deviation between the control amount and the control target value, A three-position control method, wherein a correction process is performed to bring the control target value used when calculating the deviation closer to the set value. 2. When the control amount suddenly changes and exceeds the upper limit,
The high-order control target value is forcibly set as the initial high-order control target value, and when the control amount changes suddenly and exceeds the lower limit value, the low-order control target value is forcibly set as the initial low-order control target value. 3. The three-position control method according to 1. 3. A control amount raising means for raising a control amount,
A three-position control device that controls a control amount to be held around a set value by a control amount lowering unit that lowers a control amount, wherein the three-position control device includes a control unit and a target value correction unit. The control means is capable of controlling the control amount lowering means by an upper control target value, and is capable of controlling the control amount increasing means by a lower control target value; A three-position control device, wherein a correction process is performed using a deviation between the control target value and the control target value to make the control target value used in calculating the deviation close to the set value. 4. A control amount raising means for raising a control amount,
A three-position control device that controls a control amount to be held around a set value by a control amount lowering unit that lowers a control amount, wherein the three-position control device includes a control unit, a target value correction unit, and a target. Value forcible change means, wherein the control means is capable of controlling the control amount lowering means by an upper control target value, and is capable of controlling the control amount increasing means by a lower control target value; Value correction means, using a deviation between the control amount and the control target value, performing a correction process of bringing the control target value used when calculating the deviation closer to the set value; The three-position control device, wherein the control means is capable of forcibly changing the control target value to an initial value when the control amount reaches a preset limit value.