Active air supply type transformer substation main transformer chamber cooling method and system

Abstract

The invention provides an active air supply type transformer substation main transformer chamber cooling method and system, and the method comprises the steps: obtaining an oil temperature set value Ts, a top oil temperature measurement value Tc, and a radiation temperature Td, calculating a temperature difference value delta T according to Ts and Tc, calculating a correction value delta T according to Td through a proportional function Fw, and inputting the difference value between the temperature difference value delta T and the temperature correction value delta T into a PID algorithm, temperature control feedback used for adjusting the air supply amount is output; the PID algorithm comprises a proportionality coefficient Kp, a differential coefficient Kd and an integral coefficient Ki, and the integral coefficient Ki is equal to 0. According to the method, the integral part in the PID algorithm is deleted, and the correction value delta T is introduced, so that the corrected temperature difference value delta T is directly associated with the top oil temperature measurement value Tc, and frequent start and stop of the fan are avoided while the response speed of the fan for cooling is increased.

Description

Technical Field

[0001] This invention relates to the field of main transformer room cooling technology, specifically to an active air supply method and system for cooling the main transformer room of a substation. Background Technology

[0002] The main transformer (MT) is the core equipment in a substation, carrying out numerous functions such as voltage conversion and impedance transformation. With rising ambient temperatures due to global warming and the continuous increase in residential user load capacity, summer temperature rises are becoming increasingly pronounced. To control the temperature rise of the main transformer and improve power supply reliability, measures such as adding heat sinks to the main transformer, increasing the number of heat dissipation channels in the main transformer room, and installing air conditioners or powerful fans in the main transformer room are commonly used to reduce temperature rise and improve the power supply reliability of the main transformer.

[0003] However, among the substations already in operation, 35kV substations generally suffer from long operating times, high load ratios, and severe equipment aging. Furthermore, compared to high-voltage substations and outdoor substations, the main transformer room in 35kV indoor substations has limited space, resulting in significant current-induced thermal effects and harsher operating conditions.

[0004] Given that the existing configuration of the main transformer room cannot meet the transformer cooling requirements, in order to ensure the normal operation of the equipment, it is necessary to increase the number of personnel to continuously monitor the status of the main transformer during the summer heavy load period. If necessary, it may even be necessary to work with the maintenance unit to perform live water flushing of the main transformer equipment, which increases the safety hazards to personnel and the power grid.

[0005] To address the aforementioned issues, existing technologies propose adding cooling equipment such as fans and air conditioners, but these suffer from uneven heating and cooling circulation and low levels of intelligence. Other existing technologies propose designing water vapor cooling devices for the transformer's heat sinks, but this involves significant retrofitting work, high maintenance costs, and a substantial increase in humidity within the transformer room. Therefore, designing a highly reliable, intelligent, environmentally friendly, and easily scalable substation transformer room cooling system is of great importance. Summary of the Invention

[0006] In view of this, the problem to be solved by the present invention is to provide an active ventilation method and system for cooling the main transformer room of a substation. By removing the integral part of the PID algorithm and introducing a correction value δT, the corrected temperature difference ΔT is directly correlated with the measured top oil temperature T. c This improves the response speed of cooling fans while avoiding frequent start-stop cycles.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for cooling the main transformer room of a substation using active ventilation includes obtaining the oil temperature setpoint T of the top oil temperature of the main transformer. sThe measured value of the top oil temperature T of the main transformer c Radiant temperature T of indoor heat dissipation gas d According to the oil temperature setpoint T s Compared with the measured oil temperature T at the top layer c Calculate the temperature difference ΔT using the proportional function F. w Based on radiation temperature T d The correction value δT is calculated, and the difference between the temperature difference ΔT and the temperature correction value δT is input into the PID algorithm, and the output is the temperature control feedback used to adjust the air volume. The PID algorithm includes a proportional coefficient K. p Differential coefficient K d and integral coefficient K i And the integral coefficient K i =0.

[0008] Furthermore, the radiation temperature T d The temperature of the gas in the air intake area of ​​the heat sink near the main transformer.

[0009] Furthermore, the proportional function F w For: δT=kT c +b, where k is the proportionality coefficient and b is a preset value; the formula for the proportionality coefficient k is: k = 1 - cT w Where c is a preset value, T w This refers to the intake temperature of the outdoor cooling gas.

[0010] An active air supply cooling system for the main transformer room of a substation includes an air supply module for supplying outdoor heat dissipation gas into the main transformer room, a duct mechanism for supplying outdoor heat dissipation gas to the radiator below the main transformer, an exhaust module for discharging hot air from the room, and a temperature control module. The temperature control module adjusts the air supply volume of the outdoor heat dissipation gas by controlling the operation of the air supply module and the exhaust module.

[0011] Furthermore, the main transformer room is equipped with a duct system for circulating cold air. Between the air inlet and the air outlet of the duct system, there are sequentially arranged a straight rectifier section, an arc-shaped climbing section, and a bifurcation section. The rectifying section is equipped with spiral guide vanes to reduce turbulence. The cross-section of the climbing section gradually narrows to increase the flow velocity. The diversion section includes several diversion outlets, and each of the diversion outlets is equipped with annular rectifying grids to adjust the wind direction and reduce the cross-section of the diversion outlet.

[0012] Furthermore, the air outlet of the air duct mechanism is provided with a blower mechanism for blowing cold air into the gaps between the heat sink fins of the radiator. The blower mechanism includes several contraction tubes located below the radiator and arranged vertically, and the outlet ends of the contraction tubes are provided with strip-shaped rectifier grids with adjustable width and angle.

[0013] Furthermore, the inlet end of the contraction tube is sealed to the corresponding diversion outlet of the air duct mechanism, and a honeycomb plate to reduce turbulence is provided in the inlet section.

[0014] Furthermore, the gaps between the strip-shaped air vents of the strip-shaped rectifier grid and the heat sink are arranged opposite to each other.

[0015] Furthermore, the air supply module includes an air supply fan installed outside the main transformer room, the front end of the air supply fan is provided with a dustproof component, and the rear end of the air supply fan is sealed and connected to the air inlet of the air duct mechanism.

[0016] Furthermore, the outer surface of the blower is provided with an epoxy zinc-rich primer layer, a fluorocarbon heat-insulating paint layer, and a self-cleaning nano layer from the inside out.

[0017] The advantages and positive effects of this invention are: This solution features a cooling system with a supply air module and an exhaust air module working together. The supply air module delivers outdoor heat-dissipating gas into the main transformer room to cool the main transformer. The outdoor heat-dissipating gas absorbs the heat energy of the main transformer and converts it into hot air, which is then exhausted by the exhaust fan. The temperature control module controls the air supply volume of the supply air module and the exhaust air module to efficiently cool the main transformer.

[0018] Based on the common architectural features of the main transformer room, this solution designs a duct system and a blower system. The duct system can transfer all the outdoor heat dissipation gas delivered by the air supply module to the area below the heat sink and exhaust it at high speed. The blower system can further accelerate the outdoor heat dissipation gas and blow it into the gaps between the heat sinks, thereby improving the heat dissipation efficiency of the outdoor heat dissipation gas.

[0019] This solution removes the integral part of the PID algorithm and introduces a correction value δT to adjust the temperature difference ΔT, so that the corrected temperature difference ΔT is directly correlated with the measured top oil temperature T. c The correlation enables the fan's operating power to follow the measured value T of the top oil temperature. c The stepless adjustment of the changing conditions avoids the problems of rapid power saturation and frequent start-stop of cooling equipment such as fans caused by traditional PID algorithms, while ensuring the rapid response of cooling fans after fluctuations in the main transformer oil temperature.

[0020] This solution proposes setting the intake air temperature T... w The negative correlation proportionality coefficient k is used to adjust the radiation temperature T. d By generating a correction value δT, the output of the PID algorithm can be adjusted in the opposite direction to the increase or decrease of the outdoor intake air temperature, thus saving the operating power of the fan. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 A front view of the main transformer room of an active air supply substation main transformer room cooling system; Figure 2 A top view of the main transformer room of an active air supply substation main transformer room cooling system; Figure 3 A front view of the main transformer room, which includes a chimney-type air duct mechanism, as an active air supply cooling system for the main transformer room of a substation. Figure 4 A top view of a substation main transformer room containing a chimney-type ductwork mechanism, which is an active air supply type substation main transformer room cooling system. Figure 5 The curves showing the relationship between the top oil temperature of the main transformer in the substation and the radiation temperature at different locations are shown. Figure 6 This illustrates the principle of a typical temperature control PID algorithm. Figure 7 A schematic diagram of an active ventilation cooling method for the main transformer room of a substation. Figure 8 The diagram shows the changes in wind turbine power output for a typical PID control algorithm, a PID control algorithm with the integral component removed, and the control method of this application. Among them, 1. Air supply module; 2. Air duct mechanism; 201. Diversion outlet; 22. Smoke-type air duct mechanism; 2201. Smoke-type air outlet; 3. Air blower mechanism; 4. Heat sink; 5. Exhaust fan; 6. Main transformer room. Detailed Implementation

[0022] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed terms.

[0025] This invention provides an active air supply type cooling system for the main transformer room of a substation, such as... Figure 1 and Figure 2 As shown, the system includes a main transformer compartment with the main transformer installed inside. Heat sinks are installed on both the front and rear sides of the main transformer, and each heat sink includes several arranged heat dissipation fins. In one embodiment of this application, a windproof outer shell is provided on the outside of the heat sink. The bottom and top surfaces of the windproof outer shell are open, allowing outdoor cooling air to circulate only vertically, preventing the cold air from escaping and improving the cooling efficiency of the cooling air.

[0026] The main transformer room is equipped with a duct system for transporting outdoor cooling air. This system transports the outdoor cooling air to below the heat sink and ejects it at high speed. An exhaust module is located above the heat sink fins to promptly expel the hot air after cooling. The operation of the air supply and exhaust modules is as follows: the air supply module delivers outdoor cooling air into the main transformer room, where it blows across the heat sink fins and absorbs heat, cooling the main transformer. Simultaneously, the outdoor cooling air is converted into hot air and exhausted by the exhaust module. In one embodiment of this application, the exhaust mechanism includes several exhaust fans positioned opposite the heat sink fins.

[0027] The duct structure includes a straight pipe rectifying section, an arc-shaped ascending section, and a bifurcated branching section. The rectifying section reduces the proportion of turbulence in the outdoor cooling air, allowing it to enter the room quickly; the ascending section changes the direction of movement of the outdoor cooling air from horizontal to vertical; and the branching section evenly distributes the outdoor cooling air.

[0028] The rectifying section is a circular tube structure with spiral guide vanes to reduce turbulence. This reduces the proportion of turbulent gas (gas flowing in irregular directions) within the rectifying section, effectively minimizing the interference of turbulence on the overall gas velocity and increasing the gas velocity within the rectifying section. The ascending section gradually narrows its cross-section to increase velocity. The ascending section changes the gas direction and simultaneously increases gas pressure by reducing the pipe's cross-section, further increasing the gas velocity. The splitting section includes several split outlets, each equipped with annular rectifying grids to adjust airflow direction and reduce the cross-section of the split outlets. The splitting section disperses the high-speed, high-pressure outdoor cooling gas. The annular rectifying grids adjust the direction of the outdoor cooling gas while also reducing the cross-section of the split outlets, ensuring high-speed ejection of the outdoor cooling gas.

[0029] One embodiment of this application is: 1) The rectifier section pipe is straight, and the inlet end is provided with a straight pipe with a length-to-diameter ratio of L / D=8. The inner wall is provided with spiral guide ribs to reduce the initial turbulence of the airflow to below 8%. The design of the horizontal pipe can ensure that the outdoor heat dissipation gas that has just been sent into the air duct flows into the depth of the pipe quickly.

[0030] 2) The ascending section ascends gently at an 8° inclination angle, and the pipe diameter gradually contracts according to Bernoulli's equation, thereby increasing the flow velocity and controlling the static pressure loss to ΔP < 50Pa. The slow incline design at the beginning of the diversion section is to prepare for the reversal of outdoor heat dissipation gas, reduce losses during the flow process, and ensure the smooth transmission of outdoor heat dissipation gas; 3) The diversion section is a Y-shaped diversion pipe: The Y-shaped bifurcation adopts a gradually expanding tee with a radius of curvature R=3D, and the outlet end is equipped with an annular rectifier grid (porosity 85%) to ensure that the wind speed deviation rate of the two outlets is <5%. The "Y"-shaped diversion pipe divides the outdoor heat dissipation gas into two parts. By adjusting the diameter of the corresponding pipes of the two outlets of the diversion pipe, the cross-sectional area of ​​the air outlet is reduced, the pressure at the air outlet is increased, and the cold air acting directly on the radiator is strong enough, thereby ensuring heat dissipation efficiency. The outlet of the Y-shaped diversion pipe is rectangular.

[0031] The air outlet of the air duct mechanism is equipped with a blower mechanism for blowing cool air into the gaps between the heat sink fins. The blower mechanism includes several vertically arranged contraction tubes located below the heat sink, each corresponding to a branch outlet. The cross-section of the contraction tubes gradually decreases from bottom to top, which can increase the flow velocity of the outdoor cooling air. The outlet end of the contraction tube is equipped with a strip-shaped rectifier grid with adjustable width and angle. The strip-shaped air outlets of the rectifier grid are positioned opposite the gaps between the heat sink fins. The outlet of the blower mechanism is close to the gap opening of the heat sink fins, ensuring that all heat sink fins can be directly acted upon by outdoor cool air. At the same time, the outlet pressure of the blower mechanism is maximized and the air velocity blowing onto the heat sink fins is highest, which can maximize the heat dissipation efficiency of the heat sink.

[0032] The inlet section of the contraction tube is sealed to several branch outlets of the air duct mechanism. The inlet section is equipped with a honeycomb plate to reduce turbulence, thereby reducing the proportion of air turbulence in the contraction tube and minimizing interference with low flow velocity.

[0033] One embodiment of this application is: 1) A hexagonal honeycomb plate with a pore size of Φ50mm (porosity of 82%) is provided in the inlet section to reduce the airflow turbulence in the inlet section to below 6%; 2) The contraction tube forms a gradually narrowing flow channel with a contraction ratio of 1:4, increasing the flow velocity from 12m / s to 22m / s, and the static pressure conversion efficiency reaches 91% (ISO 5801 standard). 3) The outlet end has a rectangular structure, and the strip rectifier grid makes the outlet end an adjustable width strip structure (standard width 80mm, adjustment range 50-120mm). The air outlet angle can be at most 15°±1° with the heat sink, forming an attached jet effect and improving heat dissipation efficiency.

[0034] Another embodiment of the duct mechanism is as follows: the output end of the rectifier section is connected to a pipe-shaped deflector, and the output end of the deflector is sealed to the inlet section of the contraction tube. The rectifier section and the deflector together form a pipe-shaped duct mechanism, such as... Figure 4 As shown, after the outdoor cooling air enters the duct mechanism, it passes through the rectifier section and then directly into the interior of the pipe. After being buffered and redirected by the pipe-shaped deflector, it is discharged. For example... Figure 5 As shown, the "pipe" shaped installation is complete, and the built-in air outlet module has only one pipe-shaped air outlet, which is "elliptical".

[0035] The air supply module includes a blower installed outside the main transformer room. The rear end of the blower is sealed to the air inlet of the duct mechanism, and the front end of the blower is equipped with a dustproof component. In one embodiment of this application, the dustproof component includes a diamond-shaped grid on the outer side and a square grid on the inner side. The spacing between the diamond-shaped grid and the square grid is optimized using finite element topology. The aperture of the diamond-shaped grid is Φ6mm (wire diameter Φ1.2mm, 304 stainless steel); the aperture of the square grid is Φ3mm (wire diameter Φ0.8mm, 316L stainless steel). The spacing between the two grids, optimized by finite element topology, ensures protective performance (blocking biological intrusion with a body length >50mm) while reducing airflow resistance to 120Pa (compared to 210Pa for traditional single-layer filters), and the wind speed loss rate is <8%.

[0036] The outer surface of the blower is sequentially coated from the inside out with an epoxy zinc-rich primer layer, a fluorocarbon heat-insulating paint layer, and a self-cleaning nano-layer. One embodiment of this application involves selecting a fully sealed axial flow fan to improve air intake efficiency, with a blade inclination angle of 32°. Because the blower is located outdoors, and considering weather conditions and the specific requirements of the substation, an 8011-H18 aluminum alloy shell (2.5mm thickness, tensile strength ≥220MPa) is used as the rainproof cover (outer surface) of the blower. The top of the rainproof cover is inverted V-shape (45° inclination angle), and the surface is coated with a three-layer composite coating to improve its waterproof and rust-resistant performance. The bottom layer is sprayed with epoxy zinc-rich primer (dry film thickness 50μm, salt spray test ≥1000h); the middle layer is sprayed with fluorocarbon heat-insulating paint (solar radiation absorptivity α < 0.3); and the outer layer is sprayed with a self-cleaning nano-coating (water contact angle > 150°).

[0037] Both the supply and exhaust fans communicate with the temperature control module, which adjusts the airflow by regulating the operating power of the fans. The temperature control module also communicates with the top-level oil surface temperature monitoring module and the temperature acquisition module. The top-level oil surface temperature monitoring module continuously collects the measured oil temperature T at the top of the main transformer. c Top layer oil temperature T c Excessive temperature can easily lead to main transformer failure or shorten its service life. The temperature acquisition module includes a first temperature sensor and a second temperature sensor. The first temperature sensor is used to acquire the radiant temperature T between the strip rectifier grid and the heat sink. d The second temperature sensor is used to collect the intake air temperature T supplied by the air supply module. w (Outdoor heat dissipation gas temperature).

[0038] The temperature control module communicates with the substation control system via the Modbus RTU communication protocol. The temperature control module will collect the top-layer oil temperature T. c、 Radiant temperature T d and intake air temperature T w The temperature control module sends the data to the substation control system and receives temperature control feedback from the substation control system. Based on the temperature control feedback, the temperature control module adjusts the operating power of the supply fan and exhaust fan to increase the wind speed in the area around the heat sink and reduce the air temperature in the area around the heat sink, thereby effectively improving the heat dissipation efficiency of the heat sink.

[0039] A method for cooling the main transformer room of a substation using active ventilation includes obtaining the oil temperature setpoint T of the top oil temperature of the main transformer. s The measured value of the top oil temperature T of the main transformer c Radiant temperature T of indoor heat dissipation gas d According to the oil temperature setpoint T s Compared with the measured oil temperature T at the top layer cCalculate the temperature difference ΔT using the proportional function F. w Based on radiation temperature T d The correction value δT is calculated. The difference between the temperature difference ΔT and the temperature correction value δT is input into the PID algorithm, and the output is the temperature control feedback used to adjust the air supply volume. The PID algorithm includes a proportional coefficient Kp, a derivative coefficient Kd, and an integral coefficient Ki, and the integral coefficient Ki=0.

[0040] Oil temperature setpoint T s The temperature is determined by the mechanical properties of the main transformer. One embodiment of this application is as follows: In a 35kV substation, the highest oil temperature at the top layer of the main transformer is 70℃. To prevent excessively rapid aging of the oil inside the main transformer, the oil temperature is typically reduced by 10℃, i.e., the oil temperature setpoint T. s The maximum oil temperature is 60℃; an alarm will be triggered when the top layer oil temperature exceeds 70℃.

[0041] The first temperature sensor is installed inside the air supply module or blower mechanism to collect the temperature of outdoor heat dissipation gas that has not entered the indoor environment. One embodiment of this application involves: several temperature sensors being installed along the air supply duct; the average of the collected temperature values ​​is defined as the inlet air temperature T. w .

[0042] The second temperature sensor is positioned between the heat sink and the strip rectifier grid to collect the temperature of the indoor cold air entering the room but not yet dissipating heat from the heat sink (the indoor cooling gas in the air intake area of ​​the heat sink). In one embodiment of this application, three PT100 platinum resistance thermometers (temperature sensors) are evenly installed in the area between the top of the strip air vent and the bottom of the main transformer radiator. The platinum resistance thermometers are 3 cm away from the top of the strip air vent, and the average of the data from the three temperature sensors is the temperature value of the corresponding area.

[0043] like Figure 5 The figure shows the measured oil temperature T at the top layer of the main transformer in the substation without the blower and exhaust fans running. c With radiation temperature T d The relationship curves are shown, where L1 is the top oil temperature of the main transformer, and L2 to L5 are the radiation temperatures T measured at distances of 3, 5, 7, and 9 cm from the bottom of the heat sink, respectively. d As shown in the figure, the closer the temperature sensor is to the bottom of the main transformer's heat sink, the higher the radiant temperature T. d The stronger the correlation with the top oil temperature of the main transformer.

[0044] like Figure 6 The image shows a traditional PID control algorithm. Figure 8 The S2 curve shown represents the oil temperature setpoint T. s For a fixed value, once the top oil temperature measurement value T... c Exceeding the oil temperature set value T s The fan started immediately, and the integral stage K... iThe accumulation of [something] accelerates the response rate of temperature regulation, but it also easily causes the blower and exhaust fan to reach maximum operating power. Prolonged full-speed operation of the blower can cause the measured top oil temperature T of the main transformer to [increase / decrease]. c Rapidly cool down to below the oil temperature setpoint T s The blower and exhaust fan quickly stopped running.

[0045] Since the main transformer will continue to operate and generate heat, the top oil temperature measurement value T c If the temperature continues to rise, it will cause the fan to frequently start and stop during the cooling process, affecting the fan's lifespan. If the integral term K is abandoned... i This will lead to a significant decrease in the response rate of temperature regulation, affecting the timeliness and efficiency of heat dissipation.

[0046] The integral coefficient Ki=0 in the PID algorithm, based on the radiation temperature T. d Relative to the top oil temperature measurement value T c The correlation is introduced based on radiation temperature T. d The calculated correction value δT. An integral coefficient of 0 prevents excessively rapid temperature regulation from causing frequent fan start-stop cycles; the correction value δT ensures that the temperature difference ΔT is directly correlated with the measured top oil temperature T. c This correlation ensures a rapid response to temperature regulation while maintaining the correlation between the fan's operating power and the measured top oil temperature T. c By linking the control of the fan to avoid frequent full-speed starts, the continuity of fan control is improved, and energy savings can be effectively achieved. One embodiment of this application is: a proportional coefficient K. p Set to 0.1, differential coefficient K d Set to 0.05.

[0047] proportional function F w For δT=kT c +b, where k is the proportionality coefficient and b is the preset value.

[0048] Due to radiation temperature T d Mainly affected by transformer oil temperature and the temperature of outdoor cooling gas input to the blower (inlet air temperature T) w The combined effects of the indoor ambient temperature of the main transformer and the radiation temperature T d After the fan starts, it is affected by the outdoor intake air temperature T w The biggest impact comes from the fact that the fan's operating conditions need to meet the following: inlet air temperature T w The lower (leading to T) d The smaller the value of the proportionality coefficient k, the smaller the required output power of the fan. Therefore, the proportionality coefficient k is related to the inlet air temperature T. w For negative correlations, the proportionality constant k is calculated using the formula: k=1-cT w , Where c is a preset value, T w This refers to the intake temperature of the outdoor cooling gas.

[0049] One embodiment of this application is as follows: assuming c = 0.02, temperature difference ΔT = 5℃, and radiation temperature T... d The temperature is 42℃; when the intake air temperature T w At 40℃, the proportionality coefficient b = 0.2. When the intake air temperature T... w At 30℃, the proportionality coefficient b = 0.4, and the ratio of the two corrected temperature differences ΔT is: 5 - (0.2 × 4² + b) > 5 - (0.4 × 4² + b). Based on the principle of the PID algorithm, the larger the corrected temperature difference ΔT, the greater the operating power of the fan. The aforementioned proportionality coefficient k can cause the output of the feedback loop to increase with the outdoor intake air temperature T. w The increase or decrease can be adjusted in the opposite direction to achieve energy-saving requirements and increase the intelligence and environmental friendliness of the control scheme.

[0050] like Figure 8 As shown, S1 is the wind turbine power output curve under the scheme of this application, S2 is the wind turbine power output curve under traditional PID control, and S3 is the curve with only the integral component removed (integral coefficient K). i =0, but T is not introduced. d The power output curves of the fan under the feedback loop are shown. It can be seen that the slope of curve S1 at its starting point is much greater than that of curve S3, indicating that curve S1 has a faster response rate than S3. While curve S2 has a fast response speed, it fluctuates more frequently, with the fan starting and stopping twice a day. Curve S2, on the other hand, exhibits stable fluctuations, with the fan starting and stopping only once a day. This solution reduces the probability of frequent fan start-stops. In summary, the solution proposed in this application features fast response speed and smooth power output, ensuring cooling while extending the service life of the fan.

[0051] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of this patent.

Claims

1. A method for cooling the main transformer room of a substation using an active ventilation system, characterized in that, This includes obtaining the oil temperature setpoint T of the top oil temperature of the main transformer. s The measured value of the top oil temperature T of the main transformer c Radiant temperature T of indoor heat dissipation gas d According to the oil temperature setpoint T s Compared with the measured oil temperature T at the top layer c Calculate the temperature difference ΔT using the proportional function F. w Based on radiation temperature T d The correction value δT is calculated, and the difference between the temperature difference ΔT and the temperature correction value δT is input into the PID algorithm, and the output is the temperature control feedback used to adjust the air volume. The PID algorithm includes a proportional coefficient K. p Differential coefficient K d and integral coefficient K i And the integral coefficient K i =0.

2. The active ventilation method for cooling the main transformer room of a substation according to claim 1, characterized in that, The radiation temperature T d The temperature of the gas in the air intake area of ​​the heat sink near the main transformer.

3. The active ventilation method for cooling the main transformer room of a substation according to claim 1, characterized in that, The proportional function F w for: δT=kT c +b, Where k is the proportionality coefficient and b is the preset value; The formula for the proportionality coefficient k is: k=1-cT w , Where c is a preset value, T w This refers to the intake temperature of the outdoor cooling gas.

4. An active air supply type cooling system for the main transformer room of a substation, comprising an active air supply type cooling method for the main transformer room of a substation according to any one of claims 1-3, characterized in that, It includes an air supply module for supplying outdoor heat dissipation gas into the main transformer room, an air duct mechanism for supplying outdoor heat dissipation gas to the area below the radiator of the main transformer, an exhaust module for discharging indoor hot air, and a temperature control module. The temperature control module adjusts the air supply volume of outdoor heat dissipation gas by controlling the operation of the air supply module and the exhaust module.

5. The active air supply type substation main transformer room cooling system according to claim 4, characterized in that, The main transformer room is equipped with a duct system for circulating cold air. Between the air inlet and the air outlet of the duct system, there are sequentially arranged a straight rectifier section, an arc-shaped climbing section, and a bifurcation section. The rectifying section is equipped with spiral guide vanes to reduce turbulence. The cross-section of the climbing section gradually narrows to increase the flow velocity. The diversion section includes several diversion outlets, and each of the diversion outlets is equipped with annular rectifying grids to adjust the wind direction and reduce the cross-section of the diversion outlet.

6. The active ventilation type substation main transformer room cooling system according to claim 1, characterized in that, The air outlet of the air duct mechanism is equipped with a blower mechanism for blowing cold air into the gaps between the heat sink fins of the radiator. The blower mechanism includes several contraction tubes located below the radiator and arranged vertically, and the outlet ends of the contraction tubes are provided with strip-shaped rectifier grids with adjustable width and angle.

7. The active air supply type substation main transformer room cooling system according to claim 6, characterized in that, The inlet end of the contraction tube is sealed to the corresponding diversion outlet of the air duct mechanism, and a honeycomb plate to reduce turbulence is provided in the inlet section.

8. The active ventilation type substation main transformer room cooling system according to claim 6, characterized in that, The gap between the strip-shaped air vents of the strip-shaped rectifier grid and the heat sink is arranged opposite to each other.

9. The active ventilation type substation main transformer room cooling system according to claim 4, characterized in that, The air supply module includes an air supply fan installed outside the main transformer room. The front end of the air supply fan is equipped with a dustproof component, and the rear end of the air supply fan is sealed to the air inlet of the air duct mechanism.

10. The active ventilation type substation main transformer room cooling system according to claim 4, characterized in that, The outer surface of the blower is provided with an epoxy zinc-rich primer layer, a fluorocarbon heat-insulating paint layer and a self-cleaning nano layer from the inside out.

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