Distributed water mixing system and regulation and control method

Abstract

The invention discloses a distributed water mixing system and a regulation and control method. The distributed water mixing system comprises a distributed water mixing unit, a water mixing unit controller and distributed water mixing control system software. The distributed water mixing unit comprises a main water supply valve in front of a building, a main water return valve in front of the building, a water supply and return communicating pipe, a dynamic flow control valve, a water mixing pump, an electric three-way water mixing valve, a water mixing temperature transmitter, a water return temperature transmitter, an in-building water supply valve and an in-building water return valve. A wireless communication module is arranged in the water mixing unit controller and is in two-way communication with distributed water mixing control system software, so that remote regulation and control of the water mixing unit by the control system software are realized; and meanwhile, the operation of the distributed water mixing unit can be locally controlled. And the distributed water mixing control system software automatically calculates the average return water temperature and issues an adjusting instruction of each distributed water mixing unit to a water mixing unit controller according to the average return water temperature so as to remotely control the operation adjustment of the distributed water mixing units. After the method is used for a heat supply secondary network system, the flow and the electricity consumption of a heat exchange station circulating pump can be greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of heating, ventilation, and air conditioning (HVAC), and in particular to a distributed mixing system and control method for a secondary network of a heating system. Background Technology

[0002] Currently, hydraulic imbalance is a common problem in secondary heating networks. The conventional method is to install various manual or electric regulating valves at the heating inlet in front of the building and adjust the valve opening to achieve hydraulic balance.

[0003] Another method involves installing booster pumps in the water supply pipeline in front of the building, known as a distributed booster pump system. In this system, the water volume delivered by the heat exchange station is the same as the total flow rate in the entire building. This method has the problem of high power consumption in the heating distribution system. Summary of the Invention

[0004] The purpose of this invention is to provide a distributed mixing system and control method. A distributed mixing unit is installed at the heating inlet of a building with a secondary heating network. The controller of the mixing unit collects the supply and return water temperature data in the building and uploads it to the distributed mixing system control software on the server for remote automatic operation.

[0005] This invention provides a distributed mixing system and control method, characterized in that: the distributed mixing system and control method includes a distributed mixing unit installed at the entrance of each building, a mixing unit controller, and distributed mixing system control software in a server.

[0006] The distributed mixing unit includes: a main water supply valve at the front of the building, a main water return valve at the front of the building, a water supply and return connecting pipe, a dynamic flow control valve, a mixing pump, an electric three-way mixing valve, a water supply temperature transmitter, a water return temperature transmitter, a water supply valve inside the building, and a water return valve inside the building.

[0007] In the distributed mixing unit, the dynamic flow control valve and the mixing electric pump are installed in the connecting pipe of the supply and return water pipelines, and the dynamic flow control valve is installed on the inlet side of the mixing pump.

[0008] In the distributed mixing unit, the dynamic flow control valve is a known product with a constant circulating flow function. It will not be affected by fluctuations in water pressure in the pipeline. When used in conjunction with the mixing pump, it can keep the amount of water drawn by the mixing pump from the return water pipe in the building constant.

[0009] In the distributed mixing unit, the electric three-way mixing valve can adjust the flow rate of high-temperature water from the heat exchange station locally or remotely through the distributed mixing system control software.

[0010] The mixing unit controller has functions for collecting supply and return water temperatures, controlling the mixing pump, and controlling the electric three-way mixing valve. It can control the operation of the mixing pump and the opening of the electric three-way mixing valve locally. The mixing unit controller has a built-in wireless communication module, which can communicate with the server in two directions to realize remote adjustment of the mixing pump and the electric three-way mixing valve.

[0011] The distributed mixing system control software can receive the supply water temperature, return water temperature, mixing pump operating status, and electric three-way mixing valve opening status uploaded by the mixing unit controller. It can also issue pump start / stop and electric three-way mixing valve opening adjustment commands to the mixing unit controller in both manual and automatic modes.

[0012] The distributed mixing operation process is as follows: the heat exchange station circulation pump delivers heated hot water to each building through the water supply pipe. The distributed mixing unit mixes a portion of the building's return water with the high-temperature hot water from the heat exchange station through the mixing pump and dynamic flow control valve. The resulting medium-temperature hot water then enters the building to dissipate heat. A portion of the return water returns to the heat exchange station for further heating, while another portion continues the mixing process through the mixing pump and dynamic flow control.

[0013] This repeated cycle achieves a new circulation mode that reduces the circulation flow of the heat exchange station and distribution pipelines while increasing the circulation flow within the building, which can significantly reduce the power consumption of the heat exchange station's circulation pump.

[0014] Compared with the prior art, the advantages of this invention are:

[0015] The distributed mixing system and control method described in this invention, compared with the existing distributed booster pump system, both install a water pump in front of the building. The water pump added in this invention is installed in the supply and return water connecting pipe. It draws a portion of the water from the building and mixes it with the incoming water from the heat exchange station. The mixture then passes through the building's water supply valve and the building's water supply pipe before entering the building for heat dissipation. In contrast, the existing distributed booster pump system has a water pump installed in the building's water supply pipe. It draws all the incoming water from the heat exchange station, pressurizes it, and then sends it into the building.

[0016] In existing distributed booster pump systems, the booster pump and the heat exchange station water pump are connected in series, with the heat exchange station water pump flow rate at 100%, the booster pump flow rate at 100%, and the building flow rate at 100%. In this invention, the mixing pump and the heat exchange station water pump are connected in parallel, with the heat exchange station water pump flow rate at 50%, the mixing pump flow rate at 50%, and the building flow rate at 100%.

[0017] According to relevant formulas in fluid mechanics, the change in circulating flow rate has a square relationship with the change in pump head.

[0018] According to the formula for water pump power consumption:

[0019] The power consumption of a water pump = circulation flow rate * head / 367 / pump efficiency / motor efficiency.

[0020] The present invention discloses a distributed mixing system and control method, which consumes significantly less electricity from the heat exchange station circulation pump compared to existing distributed booster pump systems.

[0021] Compared to existing systems, this invention reduces the flow rate of the circulating pump in the heat exchange station while simultaneously decreasing the pump head quadratically with the decrease in flow rate, resulting in a significant reduction in power consumption. The power savings far exceed the power consumption of the mixing pump in the distributed mixing unit installed in front of the building.

[0022] The distributed mixing system and control method described in this invention control the mixing volume through a mixing pump and a dynamic flow control valve. During equipment installation, the mixing volume is set using the dynamic flow control valve according to the building area. Since the dynamic flow control valve has the function of constant circulating water volume, the mixing volume will not change due to fluctuations in pipeline pressure, thus providing stable mixing adjustment conditions for the electric three-way mixing valve.

[0023] The distributed mixing system and control method described in this invention adopts the principle of consistent return water temperature. It can be manually adjusted locally using the mixing unit controller, or the adjustment command can be manually or automatically set in the distributed mixing control system software and sent to the mixing unit controller for remote adjustment. Attached Figure Description

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0025] Figure 1 Diagram of a distributed mixing system;

[0026] Figure 2 Diagram of a distributed mixing unit;

[0027] Figure 3 Schematic diagram of distributed mixing unit application;

[0028] Figure 4 Functional diagram of the distributed mixing control system software; Detailed Implementation

[0029] The present invention will be further explained below with reference to specific implementation schemes. The system flow, system composition, etc. shown in the accompanying drawings are only used to complement the content disclosed in the specification and are not intended to limit the conditions under which the present invention can be implemented.

[0030] See Figure 1The present invention provides a distributed mixing system and control method, which consists of a distributed mixing unit and a mixing unit controller installed in front of the heated building, and a distributed mixing control system software on a server.

[0031] See Figure 2 The distributed mixing unit includes: a main water supply valve 1 at the front of the building, a main return water valve 2 at the front of the building, a water supply valve 3 inside the building, a return water valve 4 inside the building, an electric three-way water exchange valve 5, a mixing pump 6, a dynamic flow control valve 7, a water supply and return connecting pipe 8, a mixing unit controller 9, a water supply temperature sensor 12 inside the building, a return water temperature sensor 13 inside the building, a heat exchange station 20, a heat exchange station water supply pipe 21, a heat exchange station return water pipe 22, a heat exchange station circulating pump 24, a water supply pipe 25 inside the building, and a return water pipe 26 inside the building.

[0032] The feature is that a connecting pipe 8 is installed between the water supply pipe in the inlet direction of the main water supply valve 1 and the water return pipe in the inlet direction of the main water return valve 2. A dynamic flow control valve 7 and a mixing pump 6 are installed in the connecting pipe 8, which is connected to an electric three-way water exchange valve 5. High-temperature water from the heat exchange station 20 mixes with a portion of the building's return water drawn by the mixing pump 6 within the electric three-way water exchange valve 5, and then enters the building's water supply pipe 25 through the building's water supply valve 3.

[0033] See Figure 2 The mixing unit controller 9 is installed in conjunction with the distributed mixing unit. The mixing unit controller 9 collects temperature data from the building's supply water temperature sensor 12 and return water temperature sensor 13, opening data from the electric three-way mixing valve 5, and start / stop data from the mixing pump 6. It can control the opening degree of the electric three-way mixing valve 5 and the start and stop of the mixing pump 6. The mixing unit controller 9 has a built-in wireless communication module, enabling bidirectional communication with the distributed mixing control system software on the server.

[0034] See Figure 3 The heat exchange station water supply pipe 21 is connected to the mixing unit water supply pipe through the main water supply valve 1 in front of the building. The heat exchange station return water pipe 22 is connected to the return water pipe of the water exchange unit through the main return water valve 2 in front of the building. The building water supply pipe 25 is connected to the mixing water outlet pipe of the mixing unit through the building water supply valve 3. The building return water pipe 26 is connected to the return water pipe of the mixing unit through the building return water valve 4.

[0035] See Figure 4 The functions of the distributed mixing control system software include receiving temperature data from the building's supply water temperature sensor 12 and return water temperature sensor 13 uploaded by the mixing unit controller, as well as the start / stop status of the mixing pump 6 and the opening status of the electric three-way mixing valve 5, and displaying them on the software page.

[0036] Its features include: the software can automatically calculate the average return water temperature of all distributed mixing units; and automatically generate the return water temperature deviation value between each distributed mixing unit and the average return water temperature. When the software is set to automatic operation, it uses ±0.5℃ (temperature range adjustable) of the average return water temperature as the basis for adjusting a single distributed mixing unit, and sends an adjustment command to the mixing unit controller 8 to automatically adjust the opening of the electric three-way mixing valve 5.

[0037] The process of a distributed mixing system is as follows:

[0038] Before operation, the flow opening of the dynamic flow control valve 7 in the distributed mixing unit is preset according to the different heating areas of the building. Because of the dynamic control characteristics of the dynamic flow control valve, the set flow will not change due to the change of water pressure in the pipeline, thus ensuring the stability of the mixing volume of each mixing unit.

[0039] After operation, the high-temperature water from the heat exchange station 20 flows through the water supply pipe 21, enters the mixing unit, flows through the main water supply valve 1 in front of the building, and enters the electric three-way mixing valve 5 to mix with the low-temperature return water from the mixing pump to form medium-temperature water. It then flows through the water supply valve 3 and the water supply pipe 25 in the building to enter the building's resident cooling system for heat dissipation. The low-temperature water after heat dissipation flows through the return water pipe 26 in the building. Part of it passes through the connecting pipe 8, the dynamic balance valve 7, and the mixing pump 6 to enter the electric three-way mixing valve 5 to mix with the high-temperature water from the heat exchange station to form medium-temperature water, which then enters the building for heat dissipation. The other part flows through the main return water valve 2 in front of the building, the return water pipe 22, and the heat exchange station circulation pump 24 back to the heat exchange station for further heating.

[0040] This cycle repeats itself.

[0041] During operation, the circulating water volume is adjusted as follows: the mixing volume of the mixing unit reaches a stable state due to the set flow rate of the dynamic flow control valve 7. After receiving the temperature data from the building supply water temperature sensor 12 and the building return water temperature sensor 13 uploaded by the mixing unit controller 8, the distributed mixing control system software automatically calculates the average return water temperature. If the difference between the return water temperature of a single distributed mixing unit and the average return water temperature exceeds ±0.5℃, the system adopts manual setting or automatic operation mode. The mixing controller 8 sends an adjustment command to the electric three-way mixing valve 5 to open or close the mixing valve until the error between the building return water temperature of a single mixing unit and the average return water temperature is within ±0.5℃.

[0042] Matters not covered in this invention are common knowledge.

[0043] For those skilled in the art, modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features, without departing from the principles and spirit of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A distributed mixing system and its control method, characterized in that, include: Distributed mixing unit, mixing unit controller, and distributed mixing control system software. The distributed mixing unit is installed at the heat inlet of each building in the secondary network system; the mixing unit controller is installed in conjunction with the distributed mixing unit; and the distributed mixing control system software is deployed on a server.

2. The distributed mixing unit according to claim 1, comprising:

1. Main water supply valve at the front of the building; 2. Main return water valve at the front of the building; 3. In-building water supply valve; 4. In-building return water valve; 5. Electric three-way water change valve; 6. Mixing pump; 7. Dynamic flow control valve; 8. Supply and return water connecting pipe; 9. Mixing unit controller; 12. In-building water supply temperature sensor; 13. In-building return water temperature sensor; 21. Heat exchange station water supply pipe; 22. Heat exchange station return water pipe; 25. In-building water supply pipe; 26. In-building return water pipe. The feature is that a connecting pipe 8 is installed between the water supply pipe behind the main water supply valve 1 and the return pipe in front of the main return valve 1. A dynamic flow control valve 7 and a mixing pump 6 are installed on the connecting pipe 8. The connecting pipe 8 is connected to an electric three-way water change valve 5.

3. The distributed mixing control system software according to claim 1, characterized in that: The system automatically calculates the average return water temperature of all mixing units and compares it with the return water temperature of each unit. When the temperature deviation exceeds a certain value (e.g., ±0.5℃), the distributed mixing control system software automatically sends an opening or closing command to the corresponding electric three-way mixing valve 5 for automatic adjustment.

4. The distributed mixing unit controller 9 according to claim 1, characterized in that: Each distributed mixing unit is equipped with a distributed mixing unit controller.

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