Intelligent control method based on waste heat recovery

Abstract

The invention provides an intelligent control method based on waste heat recovery, and belongs to the technical field of energy recovery. After a starting instruction of a waste heat recovery heat pump unit is received, waste heat in a data center looped network is subjected to recovery control on the secondary side of a plate heat exchanger; under the condition that supply and return water heat of a data center looped network meets the use requirement of a data machine room, heat exchange operation can be carried out as much as possible by controlling a secondary side supply and return water pipe valve and a bypass valve, adjusting the frequency of a water pump and monitoring the secondary side supply and return water temperature, so that the purposes of energy conservation and waste heat recovery are achieved.

Description

Technical Field

[0001] This invention relates to the field of energy recovery technology, and in particular to an intelligent control method based on waste heat recovery. Background Technology

[0002] With the rapid development of cutting-edge technologies such as big data, cloud computing, and artificial intelligence, data centers have gradually become a core infrastructure in the information technology field. Globally, data centers account for over 2% of annual electricity consumption, with 30%-40% of this energy used for heat dissipation, generating a large amount of low-grade waste heat (30-50℃), which directly leads to energy waste and thermal pollution. Data center PUE (Power Usage Effectiveness) requirements are becoming increasingly stringent (e.g., China requires newly built data centers to have a PUE < 1.3 by 2025), and traditional pure heat dissipation models can no longer meet energy efficiency standards. Waste heat recovery can significantly reduce carbon emissions; for example, using 1MW of waste heat from a data center for district heating can reduce CO2 emissions by approximately 3,000 tons annually.

[0003] Existing waste heat recovery technologies directly recover waste heat from servers via heat exchangers, using air-to-water heat exchangers or liquid cooling loops for building heating or hot water supply. Current control strategies are mostly single-objective PID control or static threshold regulation, such as adjusting heat pump power solely based on cooling water return temperature, or using fixed schedules to switch waste heat distribution paths (e.g., daytime heating, nighttime heat dissipation). These technologies fail to consider the coupled effects of multiple variables such as IT load, electricity prices, and ambient temperature, resulting in low overall energy efficiency, a lack of dynamic prediction and adaptive capabilities, and an inability to cope with sudden high server loads or rapid changes in external heat demand.

[0004] Therefore, a high-efficiency waste heat recovery control system is needed to meet the dynamic matching of heat source and load, the heat generation of data center changes in real time with IT load, and at the same time achieve multi-variable coordinated control with external heat demand (such as heating) to improve heat recovery efficiency and achieve the goal of high efficiency and energy saving. Summary of the Invention

[0005] To address the above technical problems, this invention provides an intelligent control method based on waste heat recovery, which solves the problems of low efficiency and poor stability in traditional technologies. It is applicable to the recovery and utilization of waste heat resources in public buildings, data centers, chemical, metallurgical, and power industries.

[0006] The technical solution of this invention is:

[0007] A smart control method based on waste heat recovery is proposed. Upon receiving the start-up command of the waste heat recovery heat pump unit, the method controls the recovery of waste heat in the data center ring network on the secondary side of the plate heat exchanger. While ensuring that the heat of the supply and return water of the data center ring network meets the requirements of the data center, the method adjusts the pump frequency and monitors the supply and return water temperature on the secondary side by controlling the valves and bypass valves of the secondary side supply and return water pipes to maximize the heat exchange operation and achieve the purpose of energy-saving waste heat recovery.

[0008] Furthermore,

[0009] By adding water pipe temperature and pressure sensors and water valve actuators to the pipelines of HVAC waste heat recovery equipment, the system can collect pipeline and water pump status information and control the start / stop and frequency adjustment of water valves and water pumps in a timely manner to achieve energy-saving control and waste heat recovery.

[0010] The control scheme includes a command initiation phase, a valve opening phase, a water pump operation phase, a temperature T0 logic judgment phase, a water pump frequency adjustment phase, a valve control phase, and a shutdown phase. All control logic is based on temperature T0.

[0011] Through the waste heat recovery unit and PLC intelligent control system, the residual heat in the data center is transferred to another office area HVAC circuit through the heat recovery plate heat exchanger, and then supplied to the office area for heating through the waste heat recovery unit.

[0012] Furthermore,

[0013] After receiving the start command for the waste heat recovery unit, the conditions for enabling the intelligent control of waste heat recovery are met.

[0014] After the start-up conditions are met, start the pump by first opening the V02 switch valve. Once the V02 valve is fully open, the pump will start running from 0Hz to the initial set frequency. At the same time, the bypass regulating valve V03 will be opened to its maximum, and the main valve V01 will be closed.

[0015] Maintain the current operating state, and after a 2-minute delay, enter the PID automatic adjustment state. The water pump frequency resumes automatic adjustment. At this time, monitor the outlet water temperature T0 of the plate heat exchanger. When the outlet water temperature is less than or equal to the set temperature, open the main regulating valve V01 and simultaneously reduce the opening of the bypass valve V03. Simultaneously, appropriately increase the frequency of the circulating pump. When the outlet water temperature of the plate heat exchanger is higher than the set temperature, reduce the operating frequency of the circulating pump until the minimum operating frequency, reduce the V01 main regulating valve, and simultaneously increase the opening of the bypass valve to lower the outlet water temperature. When the V01 main regulating valve has been reduced to the minimum opening and the temperature continues to rise, and the secondary incoming water temperature is high, the system enters the bypass short circulation state and prepares for a delayed shutdown.

[0016] Enter the shutdown procedure, stop the circulating pump, and wait for the circulating pump speed to drop to 0Hz and stop. Then close the V03 bypass valve, V01 main valve, and V02 switch valve. Wait for the startup conditions to be met again before automatically restarting.

[0017] The beneficial effects of this invention are

[0018] 1. Significantly improves data center energy efficiency

[0019] By collecting heat from data center server rooms through waste heat recovery equipment and transferring it to waste heat recovery heat pump units, the collected heat can be used for heating office areas, which can significantly reduce carbon emissions in office areas and increase energy efficiency.

[0020] 2. Effectively reduce PUE

[0021] The heat recovery system works in conjunction with the refrigeration unit to reduce the energy consumption of cooling tower fans / pumps, thereby lowering the power efficiency (PUE).

[0022] 3. Simplify the physical structure of waste heat recovery pipelines

[0023] By adding secondary side supply and return water valves, bypass pipelines and valves, the physical design meets the function of waste heat recovery, and with the support of the control system, the goal of high efficiency and energy saving is achieved.

[0024] 4. Increase the stability and reliability of waste heat recovery pipelines.

[0025] The intelligent remote control of the waste heat recovery control system is integrated into the original group control system, ensuring the stable operation of the original group control while merging the control scheme and method of waste heat recovery, making the whole system stable and reliable. At the same time, the design of the waste heat recovery pipeline is also a reliable guarantee. Attached Figure Description

[0026] Figure 1 It is a water temperature regulation logic - using only the bypass regulation diagram;

[0027] Figure 2 This is the water temperature regulation logic - using bypass and main pipeline valve regulation diagram;

[0028] Figure 3 This is a schematic diagram of a waste heat recovery system;

[0029] Figure 4 This is a point table for the waste heat recovery monitoring system.

[0030] in, Figure 1 Figure 2 It is a logic control scheme that utilizes a PLC control cabinet;

[0031] Figure 3In the diagram, (3) is the plate heat exchanger, (2) is the primary circulating water pump, and (3) is the temperature and pressure control and valve control of the pipeline. The implementation on site is carried out according to this schematic diagram.

[0032] Figure 4 This is the physical unit information that needs to be collected on-site, and the PLC control cabinet is assembled according to this point table. Detailed Implementation

[0033] 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 some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] This invention provides an intelligent control method based on waste heat recovery. It primarily involves adding water pipe temperature and pressure sensors, water valve actuators, and other equipment to the piping of HVAC waste heat recovery equipment. By collecting pipeline and pump status information, the method controls the start / stop and frequency adjustment of water valves and pumps in real time, achieving energy-saving control and waste heat recovery. This intelligent control system has two control schemes, mainly divided into seven stages: command initiation stage, valve opening stage, pump operation stage, temperature T0 logic judgment stage, pump frequency adjustment stage, valve control stage, and shutdown stage. All control logic is based on temperature T0.

[0035] This invention primarily utilizes a waste heat recovery unit and a PLC intelligent control system to transfer surplus heat from the data center to another office area's HVAC circuit via a heat recovery plate heat exchanger. The heat is then supplied to the office area for heating via the waste heat recovery unit. Its principle is based on the conservation of energy, primarily relying on the laws of thermodynamics, the principles of energy conversion and transfer, and the integrated application of materials science and engineering thermophysics, thereby improving overall energy efficiency and reducing energy waste and carbon emissions.

[0036] After receiving the start command for the waste heat recovery unit, the start conditions for the intelligent control of waste heat recovery are met. Once the start conditions are met, click the one-button start button. First, open the V02 switch valve. After the V02 valve is fully open, the water pump starts to run from 0Hz to the initial set frequency (35Hz). At the same time, the bypass regulating valve V03 is opened to the maximum, and the main valve V01 is closed. Maintaining the current operating state, after a 2-minute delay, the system enters PID automatic adjustment mode, and the water pump frequency resumes automatic adjustment. At this time, monitor the outlet water temperature T0 of the plate heat exchanger. When the outlet water temperature is less than or equal to the set temperature, slowly open the main control valve V01, simultaneously reduce the opening of the bypass valve V03, and appropriately increase the frequency of the circulating pump. When the outlet water temperature of the plate heat exchanger is higher than the set temperature, reduce the operating frequency of the circulating pump until it reaches the minimum operating frequency, reduce the opening of the main control valve V01 (which has a minimum opening limit), and simultaneously increase the opening of the bypass valve to lower the outlet water temperature. When the main control valve V01 has been reduced to its minimum opening, and the temperature continues to rise, and the secondary incoming water temperature is high, the system enters bypass short-circuit mode, preparing for a delayed shutdown. Enter the shutdown procedure, stop the circulating pump, and after the circulating pump speed drops to 0Hz and stops, close the bypass valve V03, the main control valve V01, and the on / off valve V02. Wait again for the startup conditions to be met before automatically restarting.

[0037] The above description is merely a preferred embodiment of the present invention and is used only to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A smart control method based on waste heat recovery, characterized in that, Upon receiving the start-up command of the waste heat recovery heat pump unit, the waste heat in the data center ring network is recovered and controlled on the secondary side of the plate heat exchanger. While ensuring that the heat of the supply and return water of the data center ring network meets the requirements of the data room, the pump frequency is adjusted by controlling the valves of the secondary side supply and return water pipes and the bypass valve, and the secondary side supply and return water temperature is monitored to maximize the heat exchange operation.

2. The method according to claim 1, characterized in that, By adding water pipe temperature and pressure sensors and water valve actuators to the pipelines of HVAC waste heat recovery equipment, the system can collect pipeline and water pump status information and control the start / stop and frequency adjustment of water valves and water pumps in a timely manner to achieve energy-saving control and waste heat recovery.

3. The method according to claim 2, characterized in that, The control scheme includes a command initiation phase, a valve opening phase, a water pump operation phase, a temperature T0 logic judgment phase, a water pump frequency adjustment phase, a valve control phase, and a shutdown phase. All control logic is based on temperature T0.

4. The method according to claim 3, characterized in that, Through the waste heat recovery unit and PLC intelligent control system, the residual heat in the data center is transferred to another office area HVAC circuit through the heat recovery plate heat exchanger, and then supplied to the office area for heating through the waste heat recovery unit.

5. The method according to claim 1, characterized in that, After receiving the start command for the waste heat recovery unit, the conditions for enabling the intelligent control of waste heat recovery are met.

6. The method according to claim 5, characterized in that, After the start-up conditions are met, start the pump by first opening the V02 switch valve. After the V02 valve is fully opened, the water pump will start to run from 0Hz to the initial set frequency. At the same time, the bypass regulating valve V03 will be opened to the maximum, and the main valve V01 will be closed. Maintain the current operating state, and after a 2-minute delay, enter the PID automatic adjustment state. The water pump frequency resumes automatic adjustment. At this time, monitor the outlet water temperature T0 of the plate heat exchanger. When the outlet water temperature is less than or equal to the set temperature, open the main regulating valve V01 and simultaneously reduce the opening of the bypass valve V03. Simultaneously, appropriately increase the frequency of the circulating pump. When the outlet water temperature of the plate heat exchanger is higher than the set temperature, reduce the operating frequency of the circulating pump until the minimum operating frequency, reduce the V01 main regulating valve, and simultaneously increase the opening of the bypass valve to lower the outlet water temperature. When the V01 main regulating valve has been reduced to the minimum opening and the temperature continues to rise, and the secondary incoming water temperature is high, the system enters the bypass short circulation state and prepares for a delayed shutdown.

7. The method according to claim 6, characterized in that, Enter the shutdown procedure, stop the circulating pump, and after the circulating pump speed drops to 0Hz and stops, close the V03 bypass valve, V01 main valve, and V02 switch valve.

8. The method according to claim 7, characterized in that, It will automatically turn on once the boot conditions are met.

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