An energy-saving control method for office space air conditioner based on variable static pressure design

Abstract

This invention discloses an energy-saving control method for office space air conditioning based on variable static pressure design, comprising the following steps: S1, the control host acquires the weather data and building access control data for the day, and obtains the air conditioning operation data for a certain day; S2, the control host generates a first fan frequency control signal; S3, the fan starts; S4, the fresh air generated by the fan is delivered to variable air volume (VAV) air conditioning terminals in several office spaces in the building through air ducts; S5, the VAV air conditioning terminals adjust the opening of the air valves according to the temperature change (TX) fed back by the thermostats in the office spaces; S6, the control host generates a second fan frequency control signal at regular intervals; S7, the fan frequency controller controls the fan frequency to change according to the second fan frequency control signal. Compared with the prior art, this invention solves the problem of frequent frequency adjustments of the fan based on the air volume demand at the terminal, which affects its service life.

Description

Technical Field

[0001] This invention relates to the field of variable air volume (VAV) air conditioning systems, and more particularly to an energy-saving control method for office space air conditioning based on variable static pressure design. Background Technology

[0002] Heating and air conditioning systems account for 50% of a building's total energy consumption. Variable air volume (VAV) air conditioning systems are widely used due to their advantages of high comfort and energy efficiency. For example, Chinese patent CN104566775B discloses a VAV air conditioning system and its control method. The method includes the following steps: calculating the required air volume at the VAV terminal based on preset and actual temperature parameters; simultaneously detecting the air leakage value of the VAV air conditioning system; and adjusting the fan speed in the VAV air conditioning system based on the air leakage value, the required air volume, and the maximum fan speed, so that the air supply volume at the VAV terminal is equal to the required air volume. By compensating for the air leakage value in the VAV air conditioning system with the required air volume at the VAV terminal, it effectively corrects the matching degree between the system's air supply volume and the required air volume, improving the system's stability.

[0003] In existing variable air volume (VAV) air conditioning systems that use the variable static pressure (VSP) method for airflow control, the digital controller directly calculates the fan speed that meets the minimum static pressure control based on parameters such as the opening degree, flow rate, and fan characteristics of each terminal, thereby achieving a match between the supplied air volume and the demand air volume. However, the frequent frequency adjustments of the fan based on the demand air volume at the terminal affect the fan's service life. Summary of the Invention

[0004] The purpose of this invention is to provide an energy-saving control method for office space air conditioning based on variable static pressure design, so as to solve the problem of frequent frequency adjustment of fans according to the air volume demand of the terminal, which affects the service life.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: an energy-saving control method for office space air conditioning based on variable static pressure design, comprising the following steps:

[0006] S1. The control host obtains the weather data and building access control data for the day, compares the weather data and building access control data in the database with the weather data and building access control data for the day that are closest, and obtains the air conditioning operation data for that day.

[0007] S2. The control host calculates the static pressure value that has been maintained for the longest time in the air conditioning operation data of the day, calculates the starting frequency of the fan based on the static pressure value, and generates the first fan frequency control signal.

[0008] S3. The fan starts, and the fan frequency controller controls the fan frequency according to the first fan frequency control signal.

[0009] S4. The fresh air generated by the fan is delivered to the variable air volume air conditioning terminals of several office spaces in the building through air ducts;

[0010] S5. Human body sensors are installed in the office space. The variable air volume air conditioning terminal adjusts the opening of the air valve according to the human body detection results of the human body sensors in the office space and the temperature change TX fed back by the temperature controller in the office space.

[0011] S6. The control host calculates the change in fan frequency based on the change in static pressure JX in the duct at regular intervals and generates a second fan frequency control signal.

[0012] S7. The fan frequency controller controls the fan frequency to change according to the second fan frequency control signal;

[0013] In step S5, when the human body sensor does not detect the presence of a human body in the office space, if the temperature change TX reported by the thermostat is less than the set value T1, the variable air volume air conditioning terminal does not adjust the opening of the air valve. If the temperature change TX reported by the thermostat is greater than the set value T1, the variable air volume air conditioning terminal adjusts the opening of the air valve according to the temperature change TX.

[0014] In step S6, the control host connects to the emergency adjustment unit. When the first change JX of the static pressure value in the duct monitored in real time is greater than the set threshold JX1, the emergency adjustment unit generates a frequency emergency adjustment signal. The control host generates a second fan frequency control signal based on the second change JX of the static pressure value included in the frequency emergency adjustment signal.

[0015] As a further description of the above technical solution:

[0016] In step S1, the weather data for the day includes temperature, sunshine duration, wind intensity, and wind direction.

[0017] As a further description of the above technical solution:

[0018] In step S6, the control host generates a second fan frequency control signal every 10-30 minutes based on the change JX of the static pressure value in the duct.

[0019] As a further description of the above technical solution:

[0020] In step S5, when the human body sensor detects the presence of a human body in the office space, the variable air volume air conditioning terminal adjusts the opening of the air valve according to the temperature change TX fed back by the thermostat in the office space.

[0021] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0022] 1. In this invention, when setting the static pressure setpoint of the air conditioning system for a specific day, the system selects the air conditioning operation data of the day most similar to the current day's conditions based on the weather data of the building's location and the building's access control data for that day. It then obtains the static pressure value that the air conditioning system maintains for the longest period during that day's operation, thereby setting the initial static pressure value and fan frequency. This ensures that the fan frequency matches the terminal airflow demand most of the time, achieving energy-saving control of the air conditioning system. Furthermore, it minimizes fan frequency changes and effectively protects the fan when terminal airflow demand is adjusted or the static pressure value in the duct changes.

[0023] 2. In this invention, the frequency of the fan is adjusted according to the air volume demand at the terminal, thereby achieving energy-saving control of the air conditioner. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a flowchart of an energy-saving control method for office space air conditioning based on variable static pressure design. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0028] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0029] In the description of the embodiments of the present invention, it should be noted that the terms "upper" and "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0030] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Example 1

[0032] Please see Figure 1 This invention provides a technical solution: an energy-saving control method for office space air conditioning based on variable static pressure design, comprising the following steps:

[0033] S1. The control host obtains the weather data and building access control data for the day, compares the weather data and building access control data in the database with the weather data and building access control data for the day that are closest, and obtains the air conditioning operation data for that day.

[0034] S2. The control host calculates the static pressure value that has been maintained for the longest time in the air conditioning operation data of the day, calculates the starting frequency of the fan based on the static pressure value, and generates the first fan frequency control signal.

[0035] S3. The fan starts, and the fan frequency controller controls the fan frequency according to the first fan frequency control signal.

[0036] S4. Fresh air generated by the fan is delivered to variable air volume air conditioning terminals (VAV BOX) in several office spaces in the building through air ducts.

[0037] S5. The variable air volume (VAV) air conditioning terminal adjusts the opening of the air valve based on the temperature change (TX) fed back by the thermostat in the office space.

[0038] S6. The control host calculates the change in fan frequency based on the change in static pressure JX in the duct at regular intervals and generates a second fan frequency control signal.

[0039] S7. The fan frequency controller controls the fan frequency to change according to the second fan frequency control signal.

[0040] In step S1, the weather data for the day includes temperature, sunshine duration, wind intensity, and wind direction. This effectively identifies the historical operating data of the air conditioning system that most closely matches the weather conditions of the day, thereby determining the most suitable fan frequency and duct static pressure value, reducing fan frequency variations, and minimizing fan wear while ensuring energy efficiency.

[0041] In step S6, the control host generates a second fan frequency control signal every 10-30 minutes based on the change JX in the static pressure value inside the duct. This ensures that the control host can change the fan frequency according to the change JX in the static pressure value, while also preventing the fan from changing its frequency too frequently, which would lead to high fan wear.

[0042] In step S6, the control host connects to the emergency adjustment unit. When the change in static pressure JX in the duct, which is monitored in real time, exceeds a set threshold JX1, the emergency adjustment unit generates an emergency frequency adjustment signal. Based on the change in static pressure JX included in the emergency frequency adjustment signal, the control host generates a second fan frequency control signal. That is, if the change in static pressure in the duct is too large within the control host's normal fan frequency adjustment interval, exceeding the set threshold, the control host performs an additional emergency fan frequency adjustment to effectively and promptly meet the air supply requirements of the air conditioning system.

[0043] In step S5, human body sensors are installed in the office space. The variable air volume (VAV) air conditioning terminal adjusts the opening of the air damper based on the human body detection results from the sensors and the temperature change (TX) fed back by the thermostat. Specifically:

[0044] When the human body sensor detects the presence of a human in the office space, the variable air volume (VAV) air conditioning terminal adjusts the opening of the air valve based on the temperature change (TX) reported by the thermostat in the office space.

[0045] When the human body sensor does not detect the presence of a human in the office space, the temperature change TX reported by the thermostat is less than the set value T1, and the variable air volume (VAV) air conditioning terminal does not adjust the air valve opening. When the temperature change TX reported by the thermostat is greater than the set value T1, the VAV air conditioning terminal adjusts the air valve opening according to the temperature change TX.

[0046] That is, when adjusting the opening of the air valve at the variable air volume (VAV) air conditioning terminal, if there are no people in the office space and the temperature change is not significant, the opening of the air valve should not be adjusted to avoid frequent adjustments of the air volume, which could lead to unstable static pressure in the duct, reduce the frequency of fan adjustments, and protect the fan.

[0047] Variable air volume (VAV) air conditioning terminals in multiple office spaces on the same floor of a building are connected to the same terminal air volume regulator. The terminal air volume regulator obtains human presence detection results and the damper opening of the VAV air conditioning terminals in the multiple office spaces on the same floor.

[0048] When the air valve opening of the variable air volume (VAV) air conditioning terminal in the office space with the most people on a floor is greater than 90%, the terminal air volume regulator controls the VAV air conditioning terminal opening in the office space where the temperature change TX reported by the thermostat on that floor is less than the set value T1 to decrease by 2%-10%. Thus, without changing the fan frequency, priority is given to cooling the office space with more people and greater difficulty in temperature control, increasing airflow and improving the comfort of people in the office space.

[0049] Working principle: When setting the static pressure setpoint of the air conditioning system for a specific day, the system selects the air conditioning operation data from the day most similar to the current day's conditions, based on the weather data for the building's location and the building's access control data (to determine the number of people inside the building). It then obtains the static pressure value that the air conditioning system maintained for the longest period during that day's operation, and uses this data to set the initial static pressure value and fan frequency. This ensures that the fan frequency matches the terminal airflow demand most of the time, achieving energy-saving control of the air conditioning system. Furthermore, it minimizes fan frequency changes and effectively protects the fan when terminal airflow demand adjusts or static pressure changes occur in the ductwork.

[0050] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An energy-saving control method for air conditioning of office space based on variable static pressure design, characterized in that, Includes the following steps: S1. The control host obtains the weather data and building access control data for the day, compares the weather data and building access control data in the database with the weather data and building access control data for the day that are closest, and obtains the air conditioning operation data for that day. S2. The control host calculates the static pressure value that has been maintained for the longest time in the air conditioning operation data of the day, calculates the fan starting frequency based on the static pressure value, and generates the first fan frequency control signal. S3. The fan starts, and the fan frequency controller controls the fan frequency according to the first fan frequency control signal. S4. The fresh air generated by the fan is delivered to the variable air volume air conditioning terminals of several office spaces in the building through air ducts; S5. Human body sensors are installed in the office space. The variable air volume air conditioning terminal adjusts the opening of the air valve based on the human body detection results of the human body sensors in the office space and the temperature change TX fed back by the temperature controller in the office space. S6. At regular intervals, the control host calculates the change in fan frequency based on the first change in static pressure JX in the duct and generates a second fan frequency control signal. S7. The fan frequency controller controls the fan frequency to change according to the second fan frequency control signal; In step S5, when the human body sensor does not detect the presence of a human body in the office space, if the temperature change TX reported by the thermostat is less than the set value T1, the variable air volume air conditioning terminal does not adjust the opening of the air valve. If the temperature change TX reported by the thermostat is greater than the set value T1, the variable air volume air conditioning terminal adjusts the opening of the air valve according to the temperature change TX. In step S6, the control host connects to the emergency adjustment unit. When the first change JX of the static pressure value in the duct monitored in real time is greater than the set threshold JX1, the emergency adjustment unit generates a frequency emergency adjustment signal. The control host generates a second fan frequency control signal based on the second change JX of the static pressure value included in the frequency emergency adjustment signal.

2. The energy saving control method for office space air conditioning based on variable static pressure design according to claim 1, characterized in that, In step S1, the weather data for the day includes temperature, sunshine duration, wind intensity, and wind direction.

3. The energy saving control method for office space air conditioning based on variable static pressure design according to claim 1, characterized in that, In step S6, the control host generates a second fan frequency control signal every 10-30 minutes based on the change JX of the static pressure value in the duct.

4. The energy saving control method for office space air conditioning based on variable static pressure design according to claim 1, characterized in that, In step S5, when the human body sensor detects the presence of a human body in the office space, the variable air volume air conditioning terminal adjusts the opening of the air valve according to the temperature change TX.

Images