CONTROLLING DEVICE AND METHOD

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2010-255524, filed Nov. 16, 2010, which is incorporated herein by reference.

FIELD OF TECHNOLOGY

The present invention relates to a controlling device and method in a VAV control system, or the like.

BACKGROUND

Conventionally, in the air conditioning control, an operating quantity (for example, a valve opening degree, a VAV damper opening degree, or the like) is outputted through a PID calculation from a deviation of a current temperature so that a controlled area room temperature goes to a setting temperature. In this case, in VAV (variable air volume) control for changing an airflow rate of supply air into a room, even when there is a change in the room temperature setting value, some time is required until it is reflected into the supply air temperature of the air conditioner. Because of this, there have been proposals for VAV control systems equipped with a load reset controlling function for evaluating whether or not to change the supply air temperature based on request statuses sent from various VAV control units in various controlled areas (See Japanese Unexamined Patent Application Publication H8-28940 (“JP '940”) and Japanese Unexamined Patent Application Publication H8-42902 (“JP '902”)).

However, even in the technologies disclosed in JP '940 and JP '902, there is the potential that after a user has changed the room temperature setting value, some time may be required until it is reflected in the air conditioner supply air temperature, preventing a prompt response. This problem will be explained in more detail below.

In a VAV control system, the volume of a thermal medium (cold water or hot water) that is supplied to an air conditioner is controlled by an air conditioning controlling device. In the air conditioner, the supply air, blown out by a fan, is supplied through a supply air duct to the VAV units of each of the controlled areas, to pass through the VAV units, to be supplied to the controlled areas. A VAV control unit is provided for each controlled area.

The VAV control unit calculates the required air flow rate for the controlled area based on the deviation between the room temperature measured value PV and the room temperature setting value SP of the controlled area, and controls the degree of opening of the damper of the VAV unit. The air conditioning controlling device calculates the total required air flow rate for the system as a whole from the required air flow rates sent from the VAV control units, calculates the speed of rotation of the fan from the total required air flow rate, and controls the air conditioner to achieve the calculated speed of rotation of the fan.

Additionally, the VAV control unit sends a cooling increased capacity request status when, during cooling, the room temperature measured value PV does not fall to become the room temperature setting value SP, and sends a heating increased capacity request status when, during heating, the room temperature measured value PV does not increase to the room temperature setting value SP. The air conditioning controlling device changes the air conditioner supply air temperature in accordance with the cooling increased capacity request status or heating increased capacity request status sent from the VAV control unit. Increasing the supply air temperature capacity in this way is known as “load reset control.”

Here when a user has changed the room temperature setting value SP, if, for example, the room temperature setting value SP has been reduced at the time of cooling, this produces a deviation between the room temperature setting value SP and the room temperature measured value PV, and thus the VAV control unit changes the requested airflow rates and controls the degree of opening of the VAV unit damper to cause the room temperature measured value PV to approach the room temperature setting value SP. However, if the maximum air flow rate has already been reached, then it is not possible to reduce the room temperature by changing the air flow rate. The VAV control unit sends a cooling increased capacity request status if, at the time of cooling, the room temperature measured value PV does not fall to become the room temperature setting value SP, but some time is required until the cooling increased capacity request status is sent, and thus some time will be required until the room temperature falls. In this type of load reset control, it may not be possible to respond promptly to a request from a user desiring an improvement in the temperature environment. In order to achieve a prompt response, it has been necessary to turn OFF the load reset control and to reduce the supply air temperature manually.

Additionally, heretofore the air-conditioning control has been achieved through PID control that tracks to the setting values. However, if, for example, the room temperature setting value has been changed from 26° C. to 25° C., then the request from the resident is not that “I want the temperature within the room to be 25° C.,” but rather often means that “I'm a little hot, so would like to be cooler.” In the conventional air-conditioning control, control stability is emphasized when determining the control outputs of the air-conditioning equipment so as to not overshoot, in order to go to 25° C.; however, there have been complaints that if the result of the control output calculation is a state wherein change is slow, then the resident who has changed the setting will be unaware of the change in temperature.

The present invention is to resolve the problem areas set forth above, and the object thereof is to provide a controlling device and method able to achieve prompt response to a request from a user desiring to improve the environment.

SUMMARY

The controlling device includes setting value obtaining means for obtaining a setting value for control; and changing means for changing temporarily a control output quantity in a direction that will promote tracking to a setting value through feed-forward control in accordance with a change in the setting value.

Moreover, in one example configuration of a controlling device, the setting value obtaining means obtain a controlled area room temperature setting value; and the changing means change temporarily a control output quantity, for a device for controlling the temperature environment of a controlled area, in accordance with a change in the room temperature setting value.

Moreover, in another example configuration of a controlling device, the device for controlling the temperature environment of the controlled area is an air conditioner and/or a heater; and the control output quantity is a supply air temperature setting value in an air conditioner, a flow rate to the controlled area, a degree of opening of a control valve for controlling a quantity of a thermal medium that is supplied to the air conditioner, and/or a heater operating quantity.

Moreover, in a further example configuration of a controlling device, the changing means change the control output quantity only when a resident of the controlled area has changed the room temperature setting value.

Moreover, a controlling method includes a a setting value obtaining step for obtaining a setting value for control; and a changing step for changing temporarily a control output quantity in a direction that will promote tracking to a setting value through feed-forward control in accordance with a change in the setting value.

The present examples enable an improvement in the comfort for the user through enabling responsive control based on a user request, through performing control that increases or decreases the control output quantity in the direction that will promote tracking to a setting value (feed-forward control) after detecting the action of a change in the setting value. The result is that the present invention is able to reduce extremely complaints from users that, for example, they are too hot or too cold. Moreover, the application of the present invention to a VAV control system enables increases in the decentralization of air conditioning control, in operability, and in comfort.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a structure of a VAV controlling system according to an example.

FIG. 2 is a block diagram illustrating a structure of an air conditioning controlling device of a VAV controlling system according to the example.

FIG. 3 is a flowchart illustrating the operation of the air conditioning controlling device of a VAV controlling system according to the example.

FIG. 4 is a diagram illustrating an example of the relationship between an amount of change in the room temperature setting value and an amount of change in a supply air temperature setting value.

FIG. 5 is a block diagram illustrating a structure of a VAV control unit of a VAV controlling system according to another example.

FIG. 6 is a flowchart illustrating the operation of a VAV control unit of a VAV controlling system according to the other example.

DETAILED DESCRIPTION

Forms for carrying out the present invention are explained below in reference to the figures. FIG. 1 is a block diagram illustrating a structure of a VAV controlling system according to a first form of embodiment according to the present invention.

The VAV control system of the present example includes an air conditioner 1; a cold water valve 2 for controlling the quantity of cold water to the air conditioner 1; a hot water valve 3 for controlling the quantity of hot water to the air conditioner 1; an supply air duct 7 for providing supply air from the air conditioner 1 to the controlled area 9; a VAV unit 8 for controlling, for each controlled area, the quantity of supply air supplied to the controlled area 9; a VAV control unit 11 that is a controlling device for controlling the VAV unit 8; an air conditioning controlling device 12 for controlling the cold water valve 2 and the hot water valve 3; a temperature sensor 13 for measuring the room temperature of the controlled area 9; a return duct 14; an exhaust air adjusting damper 15 for adjusting the volume of air that is exhausted to the outside; a return air adjusting damper 16 for adjusting the volume of return air that is returned to the air conditioner 1; an outside air adjusting damper 17 for adjusting the volume of outside air drawn in to the air conditioner 1; a temperature sensor 18 for measuring the supply air temperature; and a temperature sensor 19 for measuring the return air temperature.

The air conditioner 1 is structured from a cooling coil 4, a heating coil 5, and a fan 6. A VAV unit 8 and a VAV control unit 11 are provided for each controlled area. A damper, not shown, is provided within the VAV unit 8, so as to be able to adjust the volume of supply air that passes through the VAV unit 8. In FIG. 1, 10 is a supply air blower vent, and 20 is an outside air intake vent.

Within the air conditioner 1, the speed of rotation of the fan 6 and the degrees of opening of the cold water valve 2 and the hot water valve 3 are controlled by the air conditioning controlling device 12. During a cooling operation, the volume of cold water supplied to the cooling coil 4 of the air conditioner 1 is controlled by the cold water valve 2. On the other hand, during a heating operation, the volume of hot water supplied to the heating coil 5 of the air conditioner 1 is controlled by the hot water valve 3. The air that is cooled by the cooling coil 4 or the air that is heated by the heating coil 5 is blown out by the fan 6. The air that is blown out by the fan 6 (that is, the supply air) is supplied through the supply air duct 7 to the VAV unit 8 of each of the controlled areas 9, so as to be supplied to each of the controlled areas 9 through the VAV units 8.

The VAV control unit 11 calculates a required air flow rate for the controlled area 9 based on the deviation between the room temperature measured value PV, measured by the temperature sensor 13 in the controlled area 9, and the room temperature setting value SP, and sends the required air flow rate value to the air conditioning controlling device 12, and also controls the opening of the damper (not shown) within the VAV unit 8 so as to ensure this required air flow rate.

The air conditioning controlling device 12 calculates a total required air flow rate value for the system as a whole from the required air flow rate values that are sent from the individual VAV control units 11, calculates the rotational speed of the fan in accordance with the total required air flow rate value, and controls the air conditioner 1 so as to produce the calculated fan rotational speed.

Moreover, the VAV control unit 11 sends a cooling increased capacity request status when the room temperature measured value PV at the time of cooling does not fall to become the room temperature setting value SP, and sends a heating increased capacity request status when the room temperature measured value PV, at the time of heating, does not rise to reach the temperature setting value SP. The air conditioning controlling device 12 changes the supply air temperature in accordance with the cooling increased capacity request status or the heating increased capacity request status that is sent from the VAV control unit.

The supply air that passes through the VAV unit 8 to be blown out from the blower vent 10 into the controlled area 9, after contributing to the cooling control in the controlled area 9, passes through the exhaust duct 14 to be exhausted through the exhaust air adjusting damper 15, but a portion thereof is returned to the air conditioner 1 as return air through the return air adjusting damper 16. Following this, outside air is drawn in, through the outside air adjusting damper 17, at a specific proportion relative to the return air that is returned to the air conditioner 1. The respective degrees of opening of the exhaust air adjusting damper 15, the return air adjusting damper 16, and the outside air adjusting damper 17 are controlled by the air conditioning controlling device 12.

The air conditioning controlling device 12, at the time of a cooling operation by the air conditioner 1, sets the degree of opening of the hot water valve 3 to 0% and controls the degree of opening of the cooling water valve 2 so that the supply air temperature measured value, measured by the temperature sensor 18, will match the supply air temperature setting value. Moreover, the air conditioning controlling device 12, at the time of a heating operation of the air conditioner 1, sets the degree of opening of the cooling water valve 2 to 0%, and controls the degree of opening of the heating water valve 3 so that the supply air temperature measured value, measured by the temperature sensor 18, will match the supply air temperature setting value.

The operations described above are the same as in the conventional VAV control systems disclosed in JP '940 and JP '902.

The distinctive characteristics of the present examples are explained next. FIG. 2 is a block diagram illustrating one configuration of an air conditioning controlling device 12 according to the present form of embodiment. FIG. 3 is a flowchart illustrating the operation of an air conditioning controlling device 12 according to the present example.

The air conditioning controlling device 12 comprises: a room temperature measured value for obtaining the room temperature measured values PV for each of the controlled areas 9, through each of the VAV control units 11; a room temperature setting value obtaining portion 121 for obtaining the room temperature setting values SP for each of the controlled areas 9 through each of the VAV control units 11; a supply air temperature measured value obtaining portion 122 for obtaining the supply air temperature measured value measured by the temperature sensor 18; an operating quantity calculating portion 123 for calculating operating quantities that represent the degrees of opening of the cold water valve 2 and the hot water valve 3; a supply air temperature changing portion 124 for changing temporarily the supply air temperature setting value in accordance with a change in the room temperature setting value SP; and an operating quantity outputting portion 125 for outputting the operating quantities to the cold water valve 2 and the hot water valve 3.

The room temperature measured value obtaining portion 120 obtains the room temperature measured values PV of each of the controlled areas 9 through each of the VAV control units 11 (FIG. 3: Step S1).

The room temperature setting value obtaining portion 121 obtains the room temperature setting values SP of each of the controlled areas 9 through each of the VAV control units 11 (FIG. 3: Step S2).

The supply air temperature measured value obtaining portion 122 obtains the supply air temperature measured value measured by the temperature sensor 18 (FIG. 3: Step S3).

The supply air changing portion 124 compares the room temperature setting value SP, obtained in Step S2, to the previous value for the room temperature setting value SP, and if there is a difference, evaluates that there has been a change in the room temperature setting value SP (YES in FIG. 3: Step S4). The supply air changing portion 124 performs the evaluation in Step S4 for the room temperature setting value SP for each individual controlled area 9.

Moreover, the supply air temperature changing portion 124, if there is a change in even one of the room temperature setting values SP, changes the supply air temperature setting value temporarily in the increasing or decreasing direction depending on the change in the room temperature setting value SP (FIG. 3: Step S5). If the room temperature setting value SP has been increased, then the supply air temperature setting value is increased, and if the room temperature setting value SP has been decreased, then the supply air temperature setting value is decreased.

At this time, the supply air temperature changing portion 124 determines the amount of change in the supply air temperature setting value from the amount of change in the room temperature setting value SP in accordance with a relationship that has been established in advance. One example of a relationship between the amount of change in the room temperature setting value SP had the amount of change in the supply air temperature setting value is illustrated in FIG. 4. If, for example, the change in the room temperature setting value SP is an increase of +2° C. relative to the previous value, then the supply air temperature changing portion 124 sets the amount of change, relative to the current value for the supply air temperature setting value, to be +2° C. Moreover, if, for example, the change in the room temperature setting value SP is a reduction of −2° C. relative to the previous value, then the supply air temperature changing portion 124 sets the amount of change, relative to the current value for the supply air temperature setting value, to be −2° C. In this way, the supply air temperature changing portion 124 changes the supply air temperature setting value temporarily. If multiple room temperature setting values SP of multiple controlled areas 9 are changed at about the same time, then the amount of change in the supply air temperature setting value may be determined in accordance with the maximum amount of change of the amounts of change in the multiple room temperature setting values SP. Note that the supply air temperature changing portion 124 may return the supply air temperature setting value to the value from prior to the change when a specific amount of time has elapsed after the change in the supply air temperature setting value.

Following this, the operating quantity calculating portion 123 calculates an operating quantity in accordance with a specific control calculating algorithm so that the supply air temperature measured value obtained in Step S3 will match the supply air temperature setting value (FIG. 3: Step S6). The control calculating algorithm is, for example, a PID.

Additionally, the operating quantity outputting portion 125 outputs, to the cold water valve 2 and the hot water valve 3, the operating quantities calculated by the operating quantity calculating portion 123 (FIG. 3: Step S7). The degrees of opening of the cold water valve 2 and the hot water valve 3 are controlled in this way, to control the volume of the thermal medium (cold water or hot water) that is supplied to the air conditioner 1. Note that, as described above, when the air conditioner 1 is performing a cooling operation, the degree of opening of the hot water valve 3 is constantly 0%, and when the air conditioner 1 is performing a heating operation, the degree of opening of the cold water valve 2 is constantly set to 0%.

The air conditioning controlling device 12 performs the processes in Step S1 through S7, as described above, at regular intervals until the air conditioning control is terminated (YES in FIG. 3: Step S8). If there is no change in a room temperature setting value SP, then normal load reset control is performed.

An operation of the room temperature setting value SP indicates a clear intention by a user regarding the temperature environment, and is different from a situation wherein there has merely been an increase or decrease in the load in the room that increases the deviation between the room temperature setting value SP and the room temperature measured value PV, and so should be responded to promptly.

In the present example, the action that is the change in the room temperature setting value is detected, and the supply air temperature setting value of the air conditioner 1 is controlled (in feed-forward control) in response thereto, to enable air conditioning control that is responsive to the request by the user, enabling improved user comfort.

Note that while in the present example the supply air temperature setting value is changed unconditionally when there is a change in the room temperature setting value, instead the change in the supply air temperature setting value may limited to only when the supply air flow rate to the controlled area 9 for which the room temperature setting value SP has changed is the maximum air flow rate. That is, if the supply air flow rate is not the maximum air flow rate, so that there is some margin, the response will be through load reset control.

Additionally, in the present example, the user that has changed the room temperature setting value SP is not identified. As users who can change the room temperature setting values SP there are residents of the controlled areas 9 and there are building administrators. Given this, the change in the supply air temperature setting value may be limited to only when the room temperature setting value SP has been changed through an operation of an operating device (not shown) that is provided in a controlled area 9, that is, only if the change in the room temperature setting value SP can be assumed to be made by a resident. That is, it is possible to respond promptly based on a request from a room resident being a request that requires a prompt response.

Another example is explained next. While a case of a VAV control system of a method wherein the supply air temperature and air flow rate are controlled was explained in the first form of embodiment, VAV control systems include also systems of methods wherein the air flow rate is controlled with a constant supply air temperature. The this example explain a case wherein the present examples are applied to such a system. The structure of the VAV control system in the present example is identical to that in the previous example, and thus the explanation uses the the same references as are in FIG. 1. However, in the present example the supply air temperature setting value will be constant, as described above.

FIG. 5 is a block diagram illustrating one configuration of a VAV control unit 11 according to the present example. FIG. 6 is a flowchart illustrating the operation of the VAV control unit 11 according to the present example.

The VAV control unit 11 includes a room temperature measured value obtaining portion 110 for obtaining a room temperature setting value PV, measured by the temperature sensor 13 of the corresponding controlled area 9; a room temperature setting value obtaining portion 111 for obtaining the room temperature setting value SP of the corresponding controlled area 9; an air flow rate calculating portion 112 for calculating the required air flow rate for the controlled area 9 based on the deviation between the room temperatures measured value PV and the room temperature setting value SP; a flow rate changing portion 113 for changing temporarily the required air flow rate depending on a change in the room temperature setting value SP; a required air flow rate value notifying portion 114 for providing notification to the air conditioning controlling device 12 of the required air flow rate value for the controlled area 9; and a controlling portion 115 for controlling the degree of opening of the damper within the VAV unit 8 so as to secure the required air flow rate.

The room temperature measured value obtaining portion 110 obtains the room temperature measured value PV of the corresponding controlled area 9 (FIG. 6: Step S10).

The room temperature setting value obtaining portion 111 obtains the room temperature setting value SP for the corresponding controlled area 9 (FIG. 6: Step S11).

The air flow rate calculating portion 112 calculates the required air flow rate for the corresponding controlled area 9 based on the deviation between the room temperature measured value PV, obtained by the room temperature measured value obtaining portion 110, and the room temperature setting value SP, obtained by the room temperature setting value obtaining portion 111 (FIG. 6: Step S12).

The flow rate changing portion compares the room temperature setting value SP obtained in Step S11 to the room temperature setting value SP obtained the previous time, and if there is a difference, evaluates that there has been a change in the room temperature setting value SP (YES in FIG. 6: Step S13).

Additionally, when there has been a change in the room temperature setting value SP, the air flow rate changing portion 113 temporarily changes the required air flow rate, calculated by the air flow rate calculating portion 112, higher or lower in accordance with the change in the room temperature setting value SP (FIG. 6: Step S14). At the time of a cooling operation, if the room temperature setting value SP is increased, then the required air flow rate is reduced, but if the room temperature setting value SP is reduced, then the required air flow rate is increased. Moreover, at the time of a heating operation, if the room temperature setting value SP is decreased, then the required air flow rate is reduced, but if the room temperature setting value SP is reduced, then the required air flow rate is decreased.

For example, if during a cooling operation with an air flow rate of 50% the room temperature setting value SP is changed from 25° C. to 26° C. by a resident of the controlled area 9, then the flow rate calculating portion 112 calculates the required air flow rate in response to this change to be 30%. In a conventional VAV control system, the degree of opening of the damper within the VAV unit 8 would be controlled to secure the required air flow rate of 30%, but in the present example, the air flow rate changing portion 113 will change the required air flow rate temporarily to, for example, 0%. The air flow rate changing portion 113 determines the amount of change of the required air flow rate from the amount of change in the room temperature setting value SP in accordance with a relationship that is set in advance. The air flow rate changing portion 113 changes the required air flow rate temporarily in this way. Note that the air flow rate changing portion 113 may return the required air flow rate setting value to the most recent value calculated by the air flow rate calculating portion 112 after a specific amount of time has elapsed since the change in the required air flow rate.

The required air flow rate value notifying portion 114 provides notification of the required air flow rate to the air conditioning controlling device 12 (FIG. 6: Step S15). As explained above, the air conditioning controlling device 12 calculates a total required air flow rate value for the system as a whole from the required air flow rate values that are sent from the individual VAV control units 11, calculates the rotational speed of the fan in accordance with the total required air flow rate value, and controls the air conditioner 1 so as to produce the calculated fan rotational speed.

The controlling portion 115 controls the degree of opening of the damper (not shown) of the VAV unit 8 in order to secure the required air flow rate (FIG. 6: Step S16).

The VAV control unit 11 performs the processes in Step S10 through S16, as described above, at regular intervals until the termination of air conditioning control (YES in FIG. 6: Step S17). A VAV control unit 11 is provided in each individual controlled area 9, and the processes illustrated in FIG. 6 are performed by the individual VAV control units 11.

In the present example, the comfort of the user can be increased through the ability to perform air conditioning control with prompt responsiveness to the requests by the users through performing changes to the VAV air flow rate through the air flow rate changing portions 113 in response to changes in the room temperature setting value SP, in addition to changing the VAV air flow rate in the same manner as is conventional through the air flow rate calculating portion 112.

Note that, in the same manner as in the above example, the change in the required air flow rate may be limited only to the those cases wherein an operating device (not shown) that is disposed in a controlled area 9 has been operated to change a room temperature setting value SP, that is, to those cases wherein it can be assumed that a resident has changed a room temperature setting value SP.

Note that each VAV control unit 11 and air conditioning controlling device 12 in both examples may each be achieved through an individual computer, having a CPU, a memory device, and an interface with the outside, and through a program for controlling these hardware resources. The CPU of each device performs the processes explained in the examples, following a program stored in the memory device.

Moreover, while in the examples the explanation was for a VAV control system, the present invention is not limited to VAV, but rather can be applied to a variety of devices for controlling the temperature environment of controlled areas. As these devices that are air-conditioners, FCU's (fan coil units), package air conditioners, heaters, and the like. Moreover, while in the first and second forms of embodiment, the supply air temperature setting value and air flow rate were changed in accordance with a change in the room temperature setting value SP, there is no limitation thereto, but rather the degree of opening of a control valve (a cold water valve or hot water valve), or an operating quantity of a heater may be changed in accordance with a change in the room temperature setting value SP. Moreover, the supply air temperature setting value, flow rate, degree of opening of a control valve, and the like, may be changed simultaneously.

The present invention can be applied to VAV control systems, and the like.

CONTROLLING DEVICE AND METHOD

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