JP3519552B2 - VAV type air conditioning system and control method thereof - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a VAV (Variable).
The present invention relates to an air volume (variable air volume) type air conditioning system and its control method, and more particularly to a VAV air conditioning system using a general-purpose motor-driven damper and its control method.

[0002]

2. Description of the Related Art In recent years, a VAV type air conditioning system has been widely adopted as an air conditioning system excellent in individual air conditioning and energy saving operation. The VAV type air-conditioning system aims to achieve the two purposes of individual air-conditioning and energy-saving operation at the same time by installing multiple dampers in the same duct system and controlling the air volume individually for each damper. Is.

By the way, conventionally, as shown in FIG.
According to an operation signal from an external control unit (not shown), the opening of the blade 16 can be adjusted by the drive motor 14 via the motor adjusting unit 12, and the amount of air blown through the duct 18 can be adjusted. So-called general-purpose motor-driven damper 10
It has been known. Such a general-purpose motor-driven damper 1
0 is inexpensive, has a small installation space, is easy to install and maintain, and has excellent operability, and is therefore used in many duct facilities.

However, it has been difficult to apply the general-purpose motor-driven damper described above to a VAV type air conditioning system. That is, a general-purpose motor-driven damper does not have a function that allows individual feedback control of static pressure and air volume for each damper, and open-loop control of air volume is performed according to an operation signal from an external control unit. It only has the function to do. Therefore, when applied to a VAV type air conditioning system in which a large number of dampers are provided in the same duct system and these must be operated at the same time, when the static pressure in the duct fluctuates greatly and the air volume is greatly disturbed, individual There is a problem that static pressure control or air volume control in a general-purpose motor-driven damper does not work well, so it is difficult to control room temperature in each zone, and it is also impossible to secure the minimum ventilation volume. Furthermore, it was more difficult to control the room temperature when an energy saving function was added to this.

Of course, even in the case of a VAV type air conditioning system using a general-purpose motor-driven damper, pressure loss in all duct paths, blower characteristics (air volume-static pressure-rotation speed), and all damper characteristics It is possible to calculate the optimum opening of each damper according to the static pressure fluctuation of the main duct by complex convergence calculation, and perform individual air conditioning for each zone by controlling the capacity of the blower. It takes a huge amount of time and effort, and it is actually difficult to realize because it is necessary to calculate the control parameters unique to each installation site.

Therefore, conventionally, the following VA
Various dedicated damper units for V-type air conditioning systems have been proposed and used.

(1) Throttle type unit This throttle type unit 20 is, as shown in FIG.
A constant air volume mechanism 24 such as a rubber bellows and a spring provided in the duct 22 absorbs the static pressure variation in the duct, and at the same time, follows the indoor load variation detected by the indoor thermostat 26, and the control section 28 regulates the constant air volume. The mechanism 24 is operated to adjust the passing air volume. However, since the pressure loss occurs due to the constant air volume mechanism, the transport power is consumed.

(2) Bypass type unit As shown in FIG. 8, the bypass type unit 30 adjusts the blades 33 by the control unit 32 in accordance with the indoor load fluctuation detected by the indoor thermostat 31 to supply the indoor power. The amount of air supplied to the air conditioning zone through the air passage 34 and the amount of bypass to the ceiling through the bypass passage 35 are adjusted. That is, in the case of the bypass type unit 30, the air supply to the air-conditioning zone is variable, but the air-conditioner processing air volume is constant. However, the bypass air means that the inside of the ceiling is air-conditioned, and that amount causes energy loss.

(3) Attraction type unit As shown in FIG. 9, this attraction type unit 40 attracts high temperature indoor air with low temperature high pressure primary air and supplies the air to the room at a mixing ratio suitable for the load. Is. Therefore, the air supply to the air conditioning zone is constant. However, since this unit itself does not have a constant air volume function, it is generally provided with a constant air volume device (CAV) on the upstream side. In this case, pressure loss occurs as in the throttle unit.

(4) Electronic unit with built-in wind speed sensor The electronic unit 50 with built-in wind speed sensor shown in FIG.
This is the most used damper, and each unit is provided with an air volume adjusting device 51. The air volume adjusting device 51 drives the drive motor 53 by the motor adjusting portion 52 to adjust the opening degree of the blade 54. You can At that time, the air flow rate adjusting device 51 receives the load data for each air conditioning zone from a thermostat (not shown) and the passing air flow rate from a wind speed sensor 55 provided on the downstream side of the blade 54 as inputs, and adjusts the opening degree of the blade 54. Therefore, it is possible to perform feedback control of the amount of air passing through the duct regardless of the static pressure in the duct.

Although some examples of the damper unit dedicated to the VAV type air conditioning system have been described above, all of these dedicated units control the static pressure and the air volume for each unit to control the temperature for each air conditioning zone. It has a problem of being expensive and occupying a large space.

[0012]

SUMMARY OF THE INVENTION The present invention is a conventional VAV.
It was made in view of the above problems of the air conditioning system, and uses a dedicated damper unit with individual feedback control mechanism (static pressure adjustment function, air volume adjustment function, room temperature adjustment function, etc.) Instead, a system is constructed using a general-purpose motor drive damper unit of the open loop control system that is inexpensive and occupies a small space, and that does not go through complicated convergence calculations for calculating control parameters. It is an object of the present invention to provide a new and improved VAV type air-conditioning system and a control method therefor.

[0013]

In order to solve the above-mentioned problems, according to a first aspect of the present invention, an air conditioner equipped with a blower capable of automatically controlling the amount of blown air, and in communication with the air conditioner Provided is a VAV type air conditioning system including an air blowing system that blows conditioned air to each air conditioning zone, and a plurality of dampers that are installed in the air blowing system and that can adjust the opening degree according to an operation signal. The VAV type air conditioning system according to the present invention is
As described in claim 1, the blower system is composed of a main duct communicating with the air conditioner and a plurality of sub-ducts branching from the main duct to reach each air-conditioning zone; the damper is provided in each sub-duct. Equipped with a static pressure detector installed at any location in the main duct and a temperature detector installed in each air conditioning zone; the blower is in the main duct detected by the static pressure detector The static pressure detection value of the unit is capable of following a predetermined static pressure set value, and the damper is provided with a capacity control unit; the damper does not have an individual feedback control system for each unit, It is a general-purpose motor-driven damper that can open-loop control the opening.
A means for controlling the opening of the damper based on the temperature detection value of each air conditioning zone and the static pressure detection value in the main duct so that the temperature detection value detected by the temperature detector follows a predetermined set temperature. It is characterized by having.

In the VAV type air conditioning system, as described in claim 2, the static pressure control by the capacity control of the blower is executed in the first control cycle (static pressure control cycle), and the opening of each damper is further controlled. The gain value of the control formula used for the control is determined according to the static pressure detection value in the main duct and the information about the current opening state of each damper, and the gain value of this control formula is the second control value. It is preferable to be updated every cycle (room temperature control cycle).

Further, in the VAV type air conditioning system, as described in claim 3, the static pressure set value is set to a third control cycle (set static pressure) based on the opening information of each damper and the static pressure detection value. It is preferable to be updated in a control cycle).

Furthermore, in the VAV type air conditioning system, as described in claim 4, the static pressure detector is installed upstream of the first branch point of the main duct for stability of control. It is preferable in terms of obtaining.

In order to solve the above problems, the second aspect of the present invention
From the viewpoint of, an air conditioner equipped with a blower capable of automatically controlling the amount of blown air; a main duct communicating with the air conditioner and capable of blowing the conditioned air to each air conditioning zone, and communicating with the air conditioner And a plurality of sub-ducts that branch from the main duct to each air conditioning zone; and a plurality of sub-ducts that are installed in each sub-duct of the blower system and whose opening can be adjusted according to an operation signal However, each of the dampers is of a general-purpose type that does not have an individual feedback control system for each unit and can open-loop control its opening according to an operation signal from the central controller. Motor-driven damper; control method of VAV type air conditioning system comprising static pressure detector installed at arbitrary location in main duct of air blowing system; temperature detector installed in each air conditioning zone Will be provided. Then, the control method of the VAV type air conditioning system according to the present invention is as described in claim 5, wherein: the static pressure set value in the main duct and the room temperature set value in each air conditioning zone are set as initial conditions; First, the static pressure control for controlling the capacity of the blower is performed so that the static pressure detection value in the main duct detected by the detector follows a predetermined static pressure set value.
The control cycle (static pressure control cycle) is performed; the deviation between the temperature detection value and the temperature setting value is set so that the temperature detection value in each air conditioning zone detected by the temperature detector follows the predetermined temperature setting value. Further, the opening degree control of each damper is executed based on the static pressure detection value in the main duct and the information about the current opening degree state of each duct.

Furthermore, when controlling the VAV type air conditioning system, as described in claim 6, the opening control of each damper is performed by detecting the static pressure in the main duct and the current opening state of each damper. It is performed based on a control formula having a gain value determined according to the information regarding the control value. The gain value of this control formula is the second control period (room temperature control period).
It is preferably updated every time.

Furthermore, in controlling the VAV type air conditioning system, as described in claim 7, the control formula for controlling the opening degree of each damper is: among the characteristics of each damper, the air flow rate. Using the range in which the ratio between the damper opening and the damper opening is a linear characteristic, the change rate of the "air volume" is calculated.

[0020]

[Equation 3]

Replaced by the change rate of ## EQU3 ## Furthermore, the pressure loss of the ventilation path in which each damper is installed is replaced by the static pressure detection value of the main duct;

[0022]

[Equation 4]

Is calculated as the output V of the control equation; and further, the damper opening information necessary for controlling the opening of each damper based on the output V of the control expression and the static pressure detection value of the main duct. Is preferably determined.

Further, when controlling the VAV type air conditioning system, as described in claim 8, the control type control parameter for controlling the opening of each damper is a predetermined air conditioning space model (for example, In a general office building with an air-conditioning area of 1000 m2 or less, preferably 500 m2 or less, it is preferable to set in advance based on an air-conditioning section in which air conditioning is possible with a so-called compact air han.

Furthermore, in controlling the VAV type air conditioning system, as described in claim 9, "air volume"
Of the air conditioning zone of the air conditioning space model from the "indoor air condition", "outside air air condition", "outside air introduction ratio", "blow air condition from air conditioner" is determined according to the air conditioning space model. It is preferable to obtain the air flow rate change rate required to change the air temperature of 1 ° C.

Furthermore, when controlling the VAV type air conditioning system, as described in claim 10, the gain value which is the control parameter of the control type has a unique value in the air conditioning zone of the air conditioning space model. It is preferably determined using "ratio of time and time constant".

Furthermore, in controlling the VAV type air conditioning system, when determining the "ratio of dead time and time constant" as described in claim 11, the dead time in the air conditioning zone of the air conditioning space model is " The time taken for the air from the air outlet to reach the temperature detector "is considered, and the maximum dead time in that case is considered as the case where the indoor air appearance is" stratified flow "and is determined according to the air conditioning space model. The maximum dead time is obtained by giving "room ceiling height", "temperature detector installation height", and "air supply amount per air conditioning area"; the air conditioning zone of the air conditioning space model corresponding to the maximum dead time The time constant gives the "room ceiling height" and "temperature detector installation height" in the air-conditioned space model, provided that "the heat capacity is only air, not affected by other zones or walls". Determined by The maximum dead time and time constant determined, it is preferable to determine the "ratio of the dead time and time constant" which has a unique value for each air conditioning zone.

Furthermore, in the control method of the VAV type air conditioning system, as described in claim 12, the minimum value of the output V of the control type is preset in accordance with the minimum ventilation volume required for each damper. Is preferred.

Furthermore, in the control method of the VAV type air conditioning system, as described in claim 13, set static pressure control for updating the static pressure set value based on the opening degree information of each damper and the static pressure detected value. Is preferably executed in the third control cycle (set static pressure control cycle).

Furthermore, in the control method of the VAV type air conditioning system, as described in claim 14, when the opening degree of any one of the dampers deviates from a preset predetermined range, the static pressure The set value is preferably updated.

Furthermore, in the control method of the VAV type air conditioning system, as described in claim 15, the static pressure detector is installed upstream of the first branch point of the main duct. It is preferable for stable control.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a VAV type air conditioning system constructed according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows the system configuration of a preferred embodiment of the VAV type air conditioning system. VA shown
The V-type air conditioning system 100 includes an air conditioner 102 including a heat exchanger 102a and a blower 102b.
The blower capacity of the blower 102b can be variably controlled by a blower adjusting unit 106 such as an inverter control panel based on an operation signal from the control unit 104.
The conditioned air from the blower 102b has a predetermined blowing system 110.
Is sent to each air conditioning zone via the. The control unit 1
04 may be a microcomputer in which a computer program is installed or a sequencer.

In the air conditioning system according to this embodiment,
The blower system 110 includes a main duct 114 extending from the blower 102b of the air conditioner 102 to a branch point 112, and a sub-duct 116 (11) branching from the branch point 112 toward each air conditioning zone.
6a, 116b, ..., 116n). Further, the damper 1 is attached to each sub-duct 116.
18 (118a, 118b, ..., 118n) are installed. In the illustrated example, the five auxiliary ducts 116a-1
5 dampers 118a-1 to 16e, respectively.
Although the configuration in which 18e is installed is shown, the present invention is not limited to such an example, and can be applied to any number of auxiliary ducts and any number of dampers. Further, in the present specification, the sub duct 116 is a ventilation path in which the damper 118 is installed, and the main duct 114 is upstream of the branch point 112 that branches the sub duct 116 in which the damper 118 on the most upstream side is installed. The side air flow path.

The damper 11 installed in each sub-duct 116
Although any of 8 can be used as long as it can variably control the air volume in the installed duct, it is preferable to use a general-purpose type 8 as already described in FIG. A motor driven damper unit 10 is used. The damper unit 10 adjusts the opening degree of the blade 16 by the drive motor 14 via the motor adjusting unit 12 according to the operation signal from the control unit 104, and the auxiliary duct 116.
It is possible to adjust the amount of air blown through the inside. As will be described later, according to the VAV type air conditioning system according to the present embodiment, the general-purpose motor drive damper unit 1 which is difficult to use in the conventional system is used.
Even when 0 is used, the optimum operation control of the system can be performed.

Note that the general-purpose motor-driven damper referred to in the present specification is different from the dedicated damper unit described with reference to FIGS. It does not have a function to perform feedback control, but only has a function to perform open-loop control of air volume according to an operation signal from an external control unit (that is, static pressure adjustment completed for each damper). Function, air volume adjustment function, room temperature adjustment function). Such a general-purpose motor-driven damper is limited in its control function,
Compared to other dedicated damper units, it is cheaper, requires less installation space, and is easy to install and maintain.
To construct a VAV type air conditioning system that has the same or better individual air conditioning characteristics and energy saving as a conventional system by using such a general-purpose motor-driven damper without using a dedicated damper unit as in the past. It is in.

Referring again to FIG. 1, each air conditioning zone 12
0 (120a, 120b, ..., 120n), the temperature detectors 122 (122a, 12a, 12) corresponding to the respective dampers 118.
2b, ..., 122n) are installed, the temperature of each air conditioning zone 120 is detected, and the detected temperature value is controlled by the control unit 104.
Can be sent to. In the illustrated example, the five temperature detectors 122a to 122e are installed in the five air conditioning zones 120a to 120e, but the present invention is not limited to such an example, and an arbitrary number of air conditioning zones are provided. It goes without saying that it is possible to install an arbitrary number of temperature detectors.

Further, a characteristic point of the VAV type air conditioning system 100 according to the present invention is that the main duct 114 is located at an arbitrary position in the main duct 114 that reaches the blower 102b of the air conditioner 102 and the branch point 112 of the blower system 110. This is the point where a static pressure detector 124 for measuring the static pressure is installed.
As the static pressure detector 124, any one can be used as long as it can detect the static pressure in the main duct 114 and send the static pressure detection value to the control unit 104. From the viewpoint of control stability, it is preferable to install the main duct 114 as close to the first branch point 112 as possible (upstream side).

Although the main duct 114 and the sub duct 116 are branched from one branch point 112 in the illustrated construction, the main duct may be branched into any sub duct. Any number of branch points may be used. However, from the viewpoint of control stability, it is preferable that the branch from the main duct 114 to the sub duct 116 is performed at one branch point 112, as in the example shown in the figure. Further, the shape of each sub duct 116 from each damper 118 to each air conditioning zone 120, the presence or absence of branching, and the number of outlets may be arbitrary. Also, the duct shape on the suction side of the blower may be any shape.

Next, a control method of the VAV type air conditioning system configured as above will be described with reference to the flow chart shown in FIG.

First, the overall control flow will be described. After starting the operation of the system, in step S1, initial conditions regarding the set static pressure value of the main duct and the set room temperature of each air-conditioned space are confirmed. As an initial condition,
It is possible to use set values according to design conditions, preset set values, set values at the time of the previous operation, and the like.

Then, in step S2, after detecting the static pressure of the main duct and the present value of the room temperature of each air-conditioned space,
Static pressure control system (step S4), room temperature control system (step S4)
6), for each of the set static pressure control system (step S8), it is determined whether or not the predetermined control cycle has been reached (steps S3, S5, S7), and the predetermined control cycle (static pressure control cycle). (Step S3), room temperature control cycle (step S5), set static pressure control cycle (step S3)
When 7)) has been reached, a predetermined control system is entered. The control unit 104 has a predetermined control cycle, that is, a static pressure control cycle (step S3), a room temperature control cycle (step S5), and a set static pressure control cycle (step S7).
Is managed in. Further, in the illustrated example, the static pressure control system (step S4), the room temperature control system (step S6), and the set static pressure control system (step S8) are shown to be sequentially performed, but the VAV type air conditioner according to the present invention is used. A characteristic point in the system control method is that each control system has a predetermined control cycle (static pressure control cycle (step S3), room temperature control cycle (step S5), set static pressure control cycle (step S).
7)), and therefore the timing of executing each control system is not limited to the order of the flow shown in FIG. 2 and can be performed in any order according to each control cycle. .

The static pressure control system (step S) according to the embodiment of the VAV type air conditioning system according to the present invention will be described below.
4), the operation of each control system of the room temperature control system (step S6) and the set static pressure control system (step S8) will be described in detail.

(1) Static pressure control system (steps S3 and S4) When a preset control cycle is reached (step S)
In 3), static pressure control is performed. Thus, by providing a predetermined control cycle (static pressure control cycle) and performing static pressure control for each cycle, the pressure propagation speed due to the duct shape and length,
It is possible to relax different control conditions such as control calculation speed and static pressure detection speed for each system. Since the response of the static pressure control is relatively fast, the static pressure control cycle can be set to a cycle shorter than the room temperature control cycle described later.

The basic operation of this static pressure control is the main duct 1
The point is that the capacity control of the blower 102b is performed by the PI operation or the PID operation so that the static pressure from the static pressure detector 124 installed in 14 follows the set static pressure value.

The control parameters (proportional gain, integral time, derivative time) in this control are preferably calculated by actual measurement, but for example, compact for a general office building with an air conditioning area of 1000 m2 or less, preferably 500 m2 or less. By assuming an air han, the actual measurement examples shown in Table 1 below can be substituted. If the external static pressure on the air supply side under the design conditions is 20 mmAq, the values in the table shown in Table 1 can be applied. This number is a value obtained by the "limit sensitivity method" when the static pressure in the main duct is set to 20 mmAq.

[0047]

[Table 1]

As described above, the VA according to the present embodiment
According to the control method for the V-type air conditioning system, mutual interference between the dampers caused by using the general-purpose motor-driven damper is effectively prevented by the static pressure control that is periodically performed at a predetermined control cycle. It is possible.

(2) Room temperature control system (steps S5, S6) When a preset control cycle is reached (step S)
5) Perform room temperature control. By providing the predetermined control cycle (room temperature control cycle) in this way, it is possible to mitigate the influence on the controllability due to the operating speed of the motor damper which differs depending on the model. Since the response of the room temperature control is slower than that of the static pressure control, the room temperature control can be performed with a relatively long control cycle.

The basic operation of the room temperature control is to control the damper opening so that the temperature detection value from the temperature detector 122 installed in each air conditioning zone 120 follows the required temperature set value. However, this control is performed by the PID operation based on the deviation between the detected temperature value and the set temperature value, the static pressure value of the main duct, and the current opening degree information of each damper. Further, the control equation and the control parameters (proportional gain, integration time, differential time) at this time are calculated by the methods shown in (a) to (i) below.

(A) First, "ZIGER & NICO
The optimum value calculation method by the transient response method of LS "is adopted. Table 2 below shows "the optimum value calculation method by the transient response method of ZIGER &NICOLS".

[0052]

[Table 2]

However, in Table 2, ΔV is the operation amount of the opening (damper opening etc.) in the transient response method, and corresponds to the output operation in the control formula. ΔPV: A change amount of a control target (indoor temperature or the like) in the transient response method, which corresponds to an input change amount in the control equation. T: time constant of room L: dead time of room TI: integration time TD: differential time

(B) Further, as shown in FIG. 3, among the characteristics of the damper, the change rate of the "air volume" is calculated by using the range in which the ratio of the air volume to the damper opening is a linear characteristic.

[0055]

[Equation 5]

Replace with the change ratio of. When a damper with linear characteristics is installed in the turbulent air flow path,
The following formula is established.

[0057]

[Equation 6]

(C) Next, the pressure loss of the air blowing path in which each damper is installed is replaced with the static pressure detection value of the main duct. ΔPi = PS (i = 1,2,3 ...) (3) PS: Static pressure value of static pressure detector installed in main duct [m
mAq] ΔPi: Pressure loss of each ventilation path from the static pressure detector of the main duct to the indoor air blow (i = 1, 2, 3, ...)

(D) Next, to change the indoor air temperature by 1 ° C., which can be calculated from the indoor air conditions used in the design of a general office building, the outside air conditions, the outside air introduction ratio, the conditions of the air blown from the air conditioner Find the change rate of air flow required for. ΔG / ΔPV = α · G (4) G: Current air volume [m3 / h] ΔG: Air volume operation amount [m3 / h] ΔPV: Indoor air change amount [° C] α: Change indoor temperature by 1 ° C Change rate (ΔG / G) [° C-1]

(E) Next, by substituting the equation (3) into the equation (2), the following equation is derived.

[0061]

[Equation 7]

Further, the following equation is derived from the equations (4) and (5).

[0063]

[Equation 8]

(F) Next, the dead time of the room is considered as "time until the air from the air outlet reaches the temperature detector". Now consider the aspect of indoor air. The minimum dead time is 0 when the air appearance is “completely diffuse mixed flow”.
Can be considered. Also, the maximum dead time is when the appearance of air is "stratified flow", and as shown in Fig. 4, depending on the direction of the stratified flow, ventilation of either the upper, lower, left, or right of the room volume based on the temperature detector is performed. You can think of it as the time it takes.

VS: Air supply amount [m3 / h] Aroom: Room floor area [m2] Room: Ceiling height [m] HT: Height of temperature detector [m] In other words, the maximum dead time can be expressed by the following formula.

[0066]

[Equation 9]

The time constant of the room corresponding to the maximum dead time can be expressed by the following equation in which the heat capacity is considered to be only air without being affected by other zones. T = Aroom · Hroom / VS (8) L / T, which is the ratio of dead time and time constant, which has a unique value in each room, can be expressed by the following equation.

[0068]

[Equation 10]

(7) The L / T peculiar to the room is specified by using the following general design conditions for the office building. The general design conditions for office buildings are as follows. Ceiling height: Room = 2.5 m Height of temperature detector: HT = 1.5 m By substituting this into the equation (9), the following values are obtained.

[0070]

[Equation 11]

(H) The range of possible dead time L of a room is specified by using the following general design conditions for an office building. General office building design conditions Ceiling height: Room = 2.5m Temperature detector height: HT = 1.5m Air supply amount per air-conditioned area: VS / Aroom = 19.8
(M3h) / m2 By substituting this into the equation (7), the following value is obtained as the range of the dead time.

[0072]

[Equation 12]

When all are integrated, the following range of dead time can be specified. 0 ≦ L ≦ 270 sec (12)

(I) The output in the control equation

[0075]

[Equation 13]

Further, the proportional gain is set by substituting the equations (6) and (10) into "the optimum value calculation method by the transient response method of ZIGER &NICCOLS" in Table 2. However, of the three values in (10), L / T
This is adopted because the adoption of = 0.6 is a safe side for proportional gain. However, of course, it is preferable from the viewpoint of controllability that the value of L / T is determined by the ceiling height of the room and the height of the temperature detector.

Further, the value of the equation (12) is set to "ZIG
Optimal value calculation method by transient response method of ER & NICOLS "
Substitute in to set the integration time and the derivative time. However, in the state where TI = TD × 4 holds,
It has been experimentally confirmed that L has the same controllability in the range of 60 sec to 400 sec, and here L = 270.
Adopt sec. The following table shows the calculation results of the proportional gain, the integral time, and the derivative time obtained as described above.

[0078]

[Table 3]

According to the VAV type air conditioning system of the present embodiment, when the room temperature control cycle is reached (step S
5), according to the PID control formula using the control parameters in Table 3, for each damper

[0080]

[Equation 14]

The static pressure in the main duct 114 is constantly detected by the static pressure detector 124, and the control unit 104
Is the static pressure detection value of the main duct 114 and the method (a) to
The required damper opening is obtained according to the output V calculated by (i), the motor 14 is driven via the motor adjusting unit 12, and the damper opening is adjusted. It should be noted here that, in the control method for the VAV type air conditioning system according to the present embodiment, each damper opening degree is the current output V and the static pressure of the main duct regardless of the room temperature control cycle of the room temperature control system. It is a point that is constantly updated and controlled by.

That is, in the control method of the VAV type air conditioning system according to the present embodiment, the PID control method for controlling each damper opening does not directly output the "damper opening" to be controlled. To

[0083]

[Equation 15]

Is a control output V, and the opening of each damper is controlled based on this output V and the static pressure detection value of the main duct 114. As described above, since the static pressure of the main duct 114 is taken into consideration when controlling the opening degree of the damper, it is possible to effectively prevent the change of the air volume due to the change of the set static pressure. In addition, P used when controlling each damper opening
Since the proportional gain of the ID control type is constantly updated every predetermined control cycle as being suitable for the actual air volume, good damper control can always be performed. In addition, the PID control formula for controlling the damper opening is set in advance for a general office building with an air conditioning area of 1000 m2 or less, preferably 500 m2 or less. As far as the target is concerned, it is possible to save the trouble of setting control parameters for each equipment.

[0085]

[Equation 16]

In the PID control equation for calculating, the output at the design air volume is

[0087]

[Equation 17]

Therefore, the minimum ventilation amount of each damper can be secured by giving each damper a ratio (C) to the air volume at the time of design and setting the following equation as the minimum value of the output in each control equation.

[0089]

[Equation 18]

As described above, the VA according to the present embodiment
According to the control method of the V type air conditioning system, the minimum ventilation rate for the design air volume is preset in the PID control equation for controlling the damper opening degree, so that the minimum ventilation rate can be secured for each damper. it can.

(3) Set static pressure control When a predetermined control cycle set in advance is reached (step S
7), set static pressure control is performed. Set static pressure control pays attention to the opening of the damper with the largest opening of all dampers.
The set static pressure is cascade controlled so that it is always within a predetermined range. For example, in the set static pressure control flow as shown in FIG. 5, in step S11,
If it is determined that the maximum opening of the damper is 100%, the set static pressure is set to 0.2 in step S12.
The operation is performed so as to increase by the amount of × Ps and reduce the opening of the maximum opening damper. On the other hand, if it is determined in step S11 and step S13 that the opening degree of the maximum opening damper is 80 to 100%, the energy saving operation is being performed, and therefore, in step S14, the setting The pressure is maintained as it is. Further, when it is determined in step S13 that the opening degree of the maximum opening damper is less than 80%, in step S12,
The set static pressure is decreased by 0.2 × Ps, and the opening of the maximum opening damper is expanded. As described above, the opening of the damper with the largest opening of all dampers is
By controlling so that it is always 80 to 100%,
It is possible to carry out energy saving operation.

In the above embodiment, the damper opening of the maximum opening is controlled to be 80 to 100%, but it goes without saying that the present invention is not limited to this example. Further, in the above-described embodiment, the set static pressure operation amount is set to operate 20% of the current static pressure detection value, but it goes without saying that the present invention is not limited to this example. Furthermore, if the energy-saving operation itself is unnecessary, the operation control may be performed so that the set static pressure control system itself is deleted from the control flow shown in FIG.

The preferred embodiments of the VAV type air conditioning system and the control method thereof constructed according to the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims,
It is understood that those of course belong to the technical scope of the present invention.

[0094]

According to the VAV type air-conditioning system and the control method thereof according to the present invention, mutual interference between dampers caused by using a general-purpose motor-driven damper can be prevented.
It can be effectively prevented by static pressure control. Also,
The change in the air flow rate due to the change in the set static pressure can be prevented by incorporating the static pressure in the control of the damper opening. Further, since the proportional gain suitable for the actual air volume is constantly updated, good damper control can always be performed. Furthermore, a predetermined air conditioning space model, for example, an air conditioning area 10
If the control parameters are obtained in advance based on a general office building having a size of 00 m2 or less, preferably 500 m2 or less, troublesome control parameter setting is not required. Furthermore, by setting the minimum ventilation rate for the design air volume in advance for each damper, the minimum ventilation volume can be secured for each damper. Further, if the set static pressure control is executed in a predetermined cycle, it is possible to execute the energy saving operation similar to that of the conventional VAV type air conditioning system.

As described above, according to the present invention, low cost, space saving, and energy saving can be achieved by using a general-purpose motor drive type damper without using a dedicated damper unit which has been conventionally required. It is possible to build a new VAV type air conditioning system.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a preferred embodiment of a VAV type air conditioning system according to the present invention.

2 is a flowchart showing an overall control flow of a control method of the VAV type air conditioning system shown in FIG.

FIG. 3 is an explanatory diagram for understanding the control method of the VAV type air conditioning system according to the present invention, and is a graph showing an opening ratio and an air volume ratio of each damper.

FIG. 4 is an explanatory diagram for understanding the control method of the VAV type air conditioning system according to the present invention, and shows the movement of the stratified flow in each air conditioning zone.

FIG. 5 is a flowchart showing a flow of set static pressure control in the control method of the VAV type air conditioning system according to the present invention.

FIG. 6 is a configuration diagram showing a schematic configuration of a general-purpose motor-driven damper.

FIG. 7 is a configuration diagram showing a schematic configuration of a conventional throttle type damper unit.

FIG. 8 is a configuration diagram showing a schematic configuration of a conventional bypass type damper unit.

FIG. 9 is a configuration diagram showing a schematic configuration of a conventional attracting damper unit.

FIG. 10 is a configuration diagram showing a schematic configuration of a conventional electronic damper unit with a built-in wind speed sensor.

[Explanation of symbols]

10 General-purpose motor-driven damper unit 12 Motor controller 14 Drive motor 16 feathers 18 damper 100 VAV air conditioning system 102 air conditioner 102a heat exchanger 102b blower 104 control unit 106 Blower control unit 110 Blower system 114 Main duct 116 Secondary duct 118 damper 120 air conditioning zones 122 Temperature detector 124 Static pressure detector

Continuation of front page (56) Reference JP-A-4-187924 (JP, A) JP-A-2-259350 (JP, A) JP-A-5-5552 (JP, A) JP-A-4-340048 (JP , A) JP 4-20737 (JP, A) JP 63-267858 (JP, A) JP 7-332732 (JP, A) JP 9-282007 (JP, A) JP 6-317335 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F24F 11/053

Claims (15)

(57) [Claims] 1. An air conditioner equipped with a blower capable of automatically controlling the amount of blown air, a blower system communicating with the air conditioner to blow the conditioned air to each air conditioning zone, and an operation signal installed in the blower system. In a VAV type air conditioning system having a plurality of dampers whose opening degree can be adjusted according to: a plurality of air blow systems branching from the main duct communicating with the air conditioner to each air conditioning zone. A sub-duct; a damper installed in each sub-duct; a static pressure detecting means installed at an arbitrary location in the main duct, and a temperature detecting means installed for each air conditioning zone. The blower comprises a capacity control means by which a static pressure detection value in the main duct detected by the static pressure detection means can follow a predetermined static pressure set value; each damper is provided for each unit. Individual feedback for It is a general-purpose motor-driven damper that can open-loop control its opening according to the operation signal from the central controller without having a control system, and the temperature detection value detected by the temperature detector. A means for controlling the opening degree of the damper based on the detected temperature value in each of the air conditioning zones and the detected static pressure value in the main duct so as to follow a predetermined set temperature. VAV type air-conditioning system. 2. The static pressure control by the capacity control of the blower is executed in a first control cycle, and the gain value of a control formula used for controlling the opening of each damper is the static pressure in the main duct. The VAV type air conditioning system according to claim 1, wherein the VAV type air conditioning system is determined according to a detected value, and the gain value of the control formula is updated every second control cycle. 3. The static pressure setting value is updated in a third control cycle based on the current information regarding the opening state of each damper and the static pressure detection value.
Or the air conditioning system according to 2. 4. The static pressure detector is the first duct of the main duct.
The air conditioning system according to claim 1, wherein the air conditioning system is installed on the upstream side of the branch point. 5. An air conditioner equipped with a blower capable of automatically controlling the amount of blown air; a main duct communicating with the air conditioner and capable of blowing conditioned air to each air conditioning zone, and communicating with the air conditioner And a plurality of sub-ducts that branch from the main duct to each air conditioning zone; and a plurality of sub-ducts that are installed in each sub-duct of the blower system and whose opening can be adjusted according to an operation signal Dampers, but each of the dampers
It is a general-purpose motor-driven damper that can open-loop control its opening according to the operation signal from the central controller without having a separate feedback control system for each unit; A control method for a VAV type air conditioning system, comprising: a static pressure detector installed at an arbitrary location in the main duct; and a temperature detector installed in each air conditioning zone. The pressure set value and the room temperature set value of each air conditioning zone are set as initial conditions; so that the static pressure detection value in the main duct detected by the static pressure detector follows a predetermined static pressure set value, The static pressure control for performing the capacity control of the blower is executed in a first control cycle; the temperature detection value in each of the air conditioning zones detected by the temperature detector follows the predetermined temperature set value. Temperature detection And the temperature setting value, the static pressure detection value in the main duct, and information about the current opening state of each damper, the opening degree control of each damper is executed; Control method for VAV type air conditioning system. 6. The opening degree control of each damper is based on a control equation having a gain value determined according to the static pressure detection value in the main duct and information regarding the current opening degree state of each damper. The control method of the VAV type air-conditioning system according to claim 5, wherein the gain value of the control equation is updated every second control cycle. 7. The control formula for controlling the opening degree of each damper is as follows: Among the characteristics of each damper, the range in which the ratio between the air volume and the damper opening degree is a linear characteristic is used, and Change rate of "air volume" [Formula 1] Replaced with the change rate of the above; further, the pressure loss of the air passage in which each damper is installed is replaced with the static pressure detection value of the main duct; Is calculated as the output V of the control expression; and damper opening information necessary for controlling the opening of each damper based on the output V of the control expression and the static pressure detection value of the main duct. Is determined;
5. A method for controlling the VAV type air conditioning system according to [4]. 8. The control parameter of the control equation for controlling the opening degree of each damper is set in advance based on a predetermined air-conditioned space model. Control method for VAV type air conditioning system. 9. The change rate of the "air volume" is determined according to the air-conditioned space model, "indoor air condition", "outside air condition", "outside air introduction ratio", "air blown out from air conditioner". The control method of the VAV type air conditioning system according to claim 8, wherein the air temperature of the air conditioning zone of the air conditioning space model is obtained as the air flow rate change rate required to change 1 ° C. from the “condition”. 10. The gain value, which is a control parameter of the control equation, is determined by using a “ratio of dead time and time constant” having a unique value in the air conditioning zone of the air conditioning space model. The VA according to claim 8 or 9.
Control method for V type air conditioning system. 11. When determining the "ratio of dead time and time constant", the dead time in the air conditioning zone of the air conditioning space model is regarded as "time until the air from the outlet reaches the temperature detector". Assuming that the maximum dead time in that case is the case where the aspect of indoor air is "stratified flow", "room ceiling height" and "temperature detector installation height" are determined according to the air-conditioned space model. , "Maximum dead time is obtained by giving" air supply amount per air-conditioning area "; The time constant of the air-conditioning zone of the air-conditioning space model corresponding to the maximum dead time is" without being affected by other zones or walls. , The heat capacity is only air ", and is obtained by giving" room ceiling height "and" temperature detector installation height "in the air-conditioned space model; from the obtained maximum dead time and time constant , In each air conditioning zone Te has a unique value, "the ratio of the dead time and the time constant"
VA according to claim 10, characterized in that
Control method for V type air conditioning system. 12. The minimum value of the output V of the control equation is set in advance according to the minimum ventilation volume required for each damper, according to claim 6, 7, 8, 9, 10 or 11. A method for controlling a VAV type air conditioning system according to any one of claims. 13. The set static pressure control for updating the static pressure set value based on the opening degree information of each damper and the static pressure detected value is executed in a third control cycle. The method for controlling a VAV type air conditioning system according to claim 6, 7, 8, 9, 10, 11 or 12. 14. The static pressure setting value is updated when the opening degree of any one of the dampers deviates from a predetermined range set in advance.
VA according to any one of 8, 9, 10, 11 or 12
Control method for V type air conditioning system. 15. The static pressure detector is installed upstream of a first branch point of the main duct.
The control method for a VAV type air conditioning system according to any one of 6, 7, 8, 9, 10, 11, 12, 13 or 14.