Micro-positive pressure-dew point double closed-loop and subdivision autonomous control system and method for Sagomean energy storage station

Abstract

The invention discloses a micro-positive pressure-dew point double closed loop and subdivision autonomous control system and method for a Sagomean energy storage station. The system forms a parallel closed loop of a micro-positive pressure ring and a dew point difference ring through differential pressure and dew point sensing in each separable sub-cabin, and the safety difference value of the micro-positive pressure relative to the outside in the cabin and the safety difference value of the dew point in the cabin relative to the outside dew point are maintained respectively. And subdivision metering and priority distribution are carried out on the drying / air supply resources through the resource scheduling bus, and air path isolation is carried out on subdivisions in case of abnormity. The system combines access control, environmental event feedforward, step pressurization self-inspection and dustproof non-return structures, realizes low dust entry and dew formation resistance, improves the station-level availability rate, and is suitable for containerization / cabin type BESS in the Sagomean environment.

Description

Technical Field

[0001] This invention belongs to the field of environmental and safety control technology of battery energy storage systems (BESS), specifically involving the technology of implementing dual closed-loop control of "in-cabin micro-positive pressure" and "dew point difference" for containerized or cabin-type BESS in "desert" environments. Background Technology

[0002] The desert and Gobi regions are characterized by high wind speeds, strong dust storms, and large diurnal temperature variations. Micro-leakage is unavoidable in containerized / bay-type BESS (Battery Safe System) enclosures, door seams, cable penetrations, and maintenance access points. When external gusts of wind, sudden temperature changes, or door openings for maintenance occur, a momentary negative pressure forms inside the bay, causing dust to be passively drawn in through all these micro-seams. Dust deposition on battery cell channels, cooling heat exchangers, busbars, and BMS connectors leads to heat dissipation degradation, creepage path formation, accelerated corrosion, and significantly increases the frequency of filter replacement and cleaning. Therefore, a continuous and controllable micro-positive pressure is needed to stably direct the leakage outwards, converting the dust ingress caused by door openings and gusts of wind into outflow, reducing the long-term impact of dust intrusion on safety and maintenance.

[0003] On the other hand, the desert experiences significant radiative cooling at night, and the temperature of the metal surfaces of the cabin (especially the top cover and corner posts) is often lower than the ambient air temperature. If the dew point of the air inside the cabin is higher than these "coldest surfaces," condensation will occur. Condensation combined with dust easily forms a conductive, wet layer, causing creepage, malfunctions, and corrosion at the busbars and terminals. Even short-term condensation will leave residual salt and corrosion products in repeated wet-dry cycles, causing irreversible deterioration. Simply controlling relative humidity is unreliable: when the temperature drops rapidly, the relative humidity will passively rise and exceed the dew point, and the "coldest surface temperature" is inconsistent in different locations, making it difficult to detect and suppress localized condensation in a timely manner. Therefore, the dew point should be the core variable to ensure that the dew point inside the cabin is always lower than the estimated "coldest surface temperature" and maintains a sufficient safety margin with the external dew point, thus preventing condensation from occurring at its source.

[0004] The shortcomings of existing technologies are as follows: First, dust prevention is generally equated with filtration or constant positive air pressure, lacking closed-loop regulation based on internal and external pressure differences and access control / gust feedforward, allowing dust to still flow in during sudden disturbances; second, humidity control is mainly based on relative humidity or dehumidification on / off switches, without tracking the safety margin of "indoor dew point - outside dew point / coldest surface temperature", making local condensation prone to occur under nighttime radiative cooling; third, multiple compartments share air conditioning / drying equipment without compartment autonomy and air path isolation, allowing abnormal compartment leaks or high humidity to be conducted through shared pipelines, forcing the entire compartment / station to reduce capacity or even shut down; fourth, there is a lack of online leak rate self-checking and setting self-adaptation, resulting in high energy consumption and difficulty in quantifying maintenance intervals. Therefore, existing solutions are unable to simultaneously achieve low dust ingress, anti-condensation, and high availability under extreme conditions in desert environments. Summary of the Invention

[0005] The purpose of this invention is to provide a BESS (Body Environment System) control system and method for desert environments. By using "micro-positive pressure inside the cabin relative to the outside" and "safe difference between the dew point inside the cabin and the dew point outside the cabin" as two parallel closed-loop variables, a mutually decoupled and coordinated control relationship is established. Combined with autonomous resource scheduling and gas path isolation of each cabin, the system can still suppress dust backflow and avoid condensation under disturbances such as door opening maintenance, gust impacts, and strong radiation cooling at night. At the same time, it ensures that abnormal cabins do not affect other cabins, shortens recovery time, reduces energy consumption, and improves station-level availability.

[0006] The technical solution of this invention: a micro-positive pressure-dew point dual closed-loop and compartmentalized autonomous control system for the Shagohuang energy storage station, comprising: The BESS compartment is divided into several compartments by partitions. Each BESS compartment 1 is equipped with a dual closed-loop environmental control unit, including a differential pressure sensor, an in-chamber dew point sensor group, a makeup air micro fan, a recirculation fan, a drying unit, and an intake / exhaust proportional valve. The differential pressure sensor, makeup air micro fan, and intake / exhaust proportional valve form a micro positive pressure loop, while the in-chamber dew point sensor group and the drying unit form a dew point differential loop. The recirculation fan is used to coordinate and mix the two loops. The resource scheduling bus, including the distribution valve group and flow meter, distributes the dry airflow to each compartment according to the flow rate; The controller operates a micro-positive pressure loop and a dew point difference loop in parallel. It receives the pressure difference ΔP between the inside and outside of the cabin from the differential pressure sensor. Using ΔP as the controlled variable, it controls the operation of the make-up air fan and the intake / exhaust proportional valve to maintain the micro-positive pressure inside the cabin relative to the outside at 30-120Pa. At the same time, the controller receives the dew point signal from the dew point sensor group inside the cabin and calculates the difference ΔTdp between the dew point inside the cabin and the dew point outside. Using ΔTdp as the controlled variable, it controls the operation of the distribution valve group and the drying unit to maintain the dew point inside the cabin at a preset difference of 5-8℃ lower than the dew point outside or no higher than the preset upper limit of the dew point. When any compartment deviates from the setting, the controller controls the distribution valve group and the drying unit to prioritize the allocation of drying and make-up air resources to the compartment that deviates from the setting and isolates that compartment from other compartments in the gas path.

[0007] Furthermore, when there is a control conflict in the dual closed loop, the controller switches priorities according to the operating mode: in the door opening and personnel entry and exit mode, it prioritizes maintaining a slight positive pressure no lower than the first set threshold; in the closed steady state mode, it prioritizes satisfying the dew point difference and maintains the slight positive pressure no lower than the second set threshold.

[0008] Furthermore, the controller includes an event feedforward module that performs positive pressure feedforward to suppress dust ingress before the door is opened, performs a rapid drying-slow pressure recovery curve after the door is closed, and actively enhances drying and recirculation capabilities under external sandstorm or nighttime rapid cooling warning conditions.

[0009] A better scheme can also be set: the controller estimates the equivalent leakage rate by performing step pressurization and pressure holding tests on the compartments and using the self-test pressurization / pressure holding module. Based on this, it adaptively corrects the micro-positive pressure target, drying load and maintenance cycle, and triggers the degraded operation of the compartment when the leakage rate exceeds the threshold, while keeping other compartments online.

[0010] Preferably, the cabin dew point sensor group is deployed in the upper part of the compartment and the door area. The controller performs consistency verification on the dew point at multiple points and uses robust estimation for the dew point difference loop to reduce the deviation caused by local hot spots or dead airflow.

[0011] Preferably, the supplementary air blower and the recirculation blower are equipped with dustproof and check structures, including a labyrinth dustproof and breathing membrane structure, which normally meets IP6X, and prevents cross-flow between compartments through one-way check in the compartment isolation state.

[0012] Preferably, the drying unit includes at least one of an adsorption drying unit and a membrane drying unit, and achieves compartmentalized metering and two-stage drying through a distribution valve and a flow metering unit, wherein the basic drying load is provided by the membrane unit and the peak drying load is provided by the adsorption unit.

[0013] A control method for the system includes: collecting the pressure difference and dew point inside and outside the compartment, and constructing a parallel closed loop of a micro-positive pressure loop and a dew point difference loop; executing positive pressure feedforward before a door opening event, and executing a rapid drying and slow pressurization recovery sequence after the door is closed until both loops reach the target simultaneously; when any compartment deviates from the setting, prioritizing the allocation of drying / replenishment resources to that compartment and isolating the gas path when necessary, while keeping non-faulty compartments online; periodically performing step pressurization self-checks to estimate the leakage rate, and adjusting the settings and maintenance strategies accordingly; when there is a sandstorm or rapid temperature drop at night, increasing the drying and recirculation capabilities, and restoring to energy-saving operating conditions after stabilization.

[0014] The beneficial effects of this invention are as follows: This invention uses dew point difference instead of relative humidity as a closed-loop variable and decouples it from micro-positive pressure control, which significantly reduces the risk of dust intrusion and condensation; compartment autonomy and gas path isolation avoid the chain reaction of abnormal compartments, improving station availability and recovery speed; event feedforward and online leak rate self-check enable the control to have predictive and adaptive capabilities, reducing annualized energy consumption and maintenance frequency; the structure is simple, adaptable to the modification of standard container cabins, and meets IP6X and related environmental test requirements. Attached Figure Description

[0015] Figure 1 This is the overall system structure of the present invention; Figure 2 This is a front view of the air replenishment micro fan and recirculation fan; Figure 3 This is a back view of the air supply micro-blower and recirculation blower; Figure 4This invention relates to the compartmentalized gas path and resource scheduling strategy; 1. BESS cabin; 1-1. Compartment partition; 1-2. Compartment access control; 2. Dual closed-loop environmental control unit; 2-1. Differential pressure sensor; 2-2. Cabin dew point sensor group; 2-3. Make-up air micro fan; 2-4. Recirculation fan; 2-5. Drying unit; 2-6. Inlet / outlet proportional valve; 2-7. Dustproof and check valve structure; 3. Resource scheduling bus; 3-1. Distribution valve group; 3-2. Flow meter; 4. Controller; 4-1. Event feedforward module; 4-2. Self-test pressurization / pressure holding module; 5. External weather / dust sensor. Detailed Implementation

[0016] A micro-positive pressure-dew point dual closed-loop and compartmentalized autonomous control system for the Shagohuang energy storage station, see [link / reference]. Figure 1 , 2 3. The BESS chamber 1 is divided into two compartments by a partition 1-1. Each BESS chamber 1 is equipped with a dual closed-loop environmental control unit 2, including a differential pressure sensor 2-1, an in-chamber dew point sensor group 2-2, a makeup air micro-fan 2-3, a recirculation fan 2-4, a drying unit 2-5, an intake / exhaust proportional valve 2-6, and a dustproof and check valve structure 2-7. The differential pressure sensor 2-1 is used to measure the pressure difference between the inside and outside of the chamber, with a range of 0-1000Pa and a resolution of ≤1Pa. The in-chamber dew point sensor group 2-2 is arranged in the upper space and door area of ​​the compartment, with a dew point accuracy of ≤±0.5℃. The controller performs consistency checks on the dew points at multiple points and uses robust estimation for the dew point differential loop to reduce deviations caused by local hot spots or dead air zones. An external meteorological / dust sensor 5 is arranged on the leeward side of the chamber.

[0017] The execution unit includes a replenishment micro-fan 2-3 capable of rapid air replenishment with variable air volume, a recirculation fan 2-4, a drying unit 2-5, and an intake / exhaust proportional valve 2-6. The replenishment micro-fan 2-3 and the recirculation fan 2-4 are equipped with dustproof and check valve structures 2-7, employing a labyrinthine dustproof and breathable membrane structure. Under normal conditions, they meet the IP6X protection level, and in the compartmentalized isolation state, one-way check valves prevent cross-flow between compartments. The drying unit 2-5 adopts a centralized adsorption drying configuration on the resource scheduling bus 3, and supplies a quantitative amount of drying airflow to each compartment through the distribution valve group 3-1 and the flow meter 3-2.

[0018] Controller 4 operates the micro-positive pressure loop and the dew point difference loop in parallel. The micro-positive pressure loop includes a differential pressure sensor 2-1, a makeup air micro-fan 2-3, and an intake / exhaust proportional valve 2-6. Controller 4 receives the pressure difference ΔP between the inside of the cabin and the outside, measured by the differential pressure sensor 2-1. ΔP is the controlled variable. By adjusting the operation of the makeup air micro-fan 2-3 and the intake / exhaust proportional valve 2-6, the airflow is regulated to maintain ΔP within the range of 30-120 Pa, with a steady-state target of 50-90 Pa. The dew point difference loop includes an in-cabin dew point sensor group 2-2, a drying unit 2-5, a distribution valve group 3-1, and a flow meter 3-2. Controller 4 receives the dew point signal from the dew point sensor group 2-2 inside the cabin, calculates the difference ΔTdp between the cabin dew point and the external dew point, and uses ΔTdp as the controlled variable in the dew point difference loop. By adjusting the operation of the drying unit 2-5 and the distribution valve group 3-1, it supplies an appropriate amount of drying airflow to the compartments to maintain the cabin dew point at a preset difference of 5-8°C lower than the external dew point, or ensures that the cabin dew point does not exceed a preset upper limit (e.g., -5°C). When any compartment deviates from the setting, the controller controls the distribution valve group 3-1 and the drying unit 2-5 to prioritize the allocation of drying and replenishment air resources to the compartment that deviates from the setting and isolates that compartment from other compartments in the air path. The recirculation fan 2-4 is used for coordination and mixing between the two loops to avoid local hot spots.

[0019] The controller 4 includes an event feedforward module 4-1, which controls the execution unit to suppress dust ingress before the door opens and to increase pressure after the door closes. When the sub-compartment access control 1-2 opens, the event feedforward module 4-1 increases ΔP to ≥90Pa 2-5 seconds before the door opens to suppress dust ingress; after the door closes, it executes a "rapid drying-slow pressure increase" recovery curve: first, it increases the drying load and recirculation amount, and then slowly increases the pressure to steady state after ΔTdp reaches the target, with a typical recovery time of 120-300 seconds. When the external weather / dust sensor 5 detects a sandstorm or rapid cooling at night, the controller controls the execution unit to operate, pre-enhancing the drying and recirculation capabilities. When there is a control conflict in the dual closed loop, the controller switches priorities according to the operating mode: in the door opening and personnel entry / exit mode, it prioritizes maintaining a slightly positive pressure no lower than the first set threshold; in the closed steady-state mode, it prioritizes satisfying the dew point difference and maintains the slightly positive pressure no lower than the second set threshold.

[0020] Controller 4 periodically performs leak rate self-checks via self-test pressurization / pressure holding module 4-2: self-test pressurization / pressure holding module 4-2 drives the actuator to replenish air to the compartment, applying a ΔP step change of +15Pa for 10-20 seconds and recording the pressure differential decay curve, fitting a first-order leakage model ΔP(t) = ΔP0·e (−t / τ)The equivalent leak rate is estimated, where ΔP(t) is the pressure difference at time t, ΔP0 is the initial pressure difference during leak rate self-testing, t is the elapsed time during leak rate self-testing, and τ is the time constant. When the leak rate increases, the controller automatically lowers the upper limit of ΔP, increases the drying priority, or shortens the maintenance cycle. When a sub-compartment experiences an abnormal leak rate or wet load, its branch is restricted or isolated via distribution valve group 3-1, maintaining only the safety lower limit ΔP ≥ 30 Pa and ΔTdp ≥ 3℃, while other sub-compartments remain online without degradation.

[0021] The drying unit 2-6 includes at least one of an adsorption drying unit and a membrane drying unit, and achieves compartmentalized metering and two-stage drying through a distribution valve 3-1 and a flow metering unit 3-2. The basic drying load is provided by the membrane type, and the peak drying load is provided by the adsorption type.

[0022] When the system is in use, it collects the pressure difference and dew point inside and outside the compartments, and constructs a parallel closed loop of micro-positive pressure loop and dew point difference loop; before the door opens, it executes positive pressure feedforward, and after the door closes, it executes a recovery sequence of rapid drying and slow pressurization until both loops reach the target simultaneously; when any compartment deviates from the setting, it prioritizes the allocation of drying / replenishment gas resources to that compartment and isolates the gas path when necessary, while non-faulty compartments remain online; it periodically performs step pressurization self-checks to estimate the leakage rate and adjusts the settings and maintenance strategies accordingly; when there is a sandstorm or rapid cooling at night, it enhances the drying and recirculation capabilities and restores to energy-saving conditions after stabilization.

[0023] This invention establishes a mutually decoupled and coordinated control relationship by treating "the slight positive pressure inside the compartment relative to the outside" and "the safe difference between the dew point inside the compartment and the dew point outside" as two parallel closed-loop variables. Combined with the autonomous resource scheduling and gas path isolation of the compartments, the system can still suppress dust backflow and avoid condensation under disturbances such as door opening maintenance, gust impacts, and strong radiation cooling at night. At the same time, it ensures that abnormal compartments do not affect other compartments, shortens recovery time, reduces energy consumption, and improves station-level availability.

[0024] Implementation results: Under the daily variation conditions of ambient wind speed of 0-15m / s and external dew point of -5 to +10℃, no condensation events were recorded during the statistical period; measured by filter material weight gain and cleaning frequency, the dust intake was reduced by about 40-60% compared with single-loop positive pressure control; the average recovery time of the entire door opening and closing process was shortened by about 25%; when a compartment fails, other compartments remain online, and the station-level availability is significantly improved.

Claims

1. A micro-positive pressure-dew point double closed loop and cabin autonomous control system for Shaguo Barren Energy Station, characterized in that, The application relates to a kind of modularized BESS cabin (1), which is divided into several sub-cabin by sub-cabin partition (1-1), and each BESS cabin (1) is provided with double closed loop environment control unit (2), including differential pressure sensor (2-1), cabin dew point sensor group (2-2), air supplementing micro fan (2-3), recirculation fan (2-4), drying unit (2-5), inlet / outlet air proportional valve (2-6); differential pressure sensor (2-1), air supplementing micro fan (2-3) and inlet / outlet air proportional valve (2-6) constitute a micro-positive pressure ring, and cabin dew point sensor group (2-2) and drying unit (2-5) constitute a dew point difference ring; recirculation fan (2-4) is used for coordination and mixing of the two rings. Resource scheduling bus (3) includes distribution valve group (3-1) and flow meter (3-2), and dry gas flow is distributed to each sub-cabin according to flow. Controller (4) runs micro-positive pressure ring and dew point difference ring in parallel, receives the pressure difference ΔP between inside and outside of the cabin from differential pressure sensor (2-1), takes ΔP as the controlled variable, controls the operation of air supplementing micro fan (2-3) and inlet / outlet air proportional valve (2-6), and maintains the micro-positive pressure of the cabin relative to the outside at 30-120 Pa; at the same time, controller (4) receives the dew point signal from cabin dew point sensor group (2-2), calculates the difference ΔTdp between the dew point of the cabin and the dew point of the outside, takes ΔTdp as the controlled variable, controls the operation of distribution valve group (3-1) and drying unit (2-5), and maintains the dew point of the cabin at a preset difference of 5-8°C lower than the dew point of the outside or not higher than a preset upper limit of the dew point; wherein, when any sub-cabin deviates from the setting, controller controls distribution valve group (3-1) and drying unit (2-5) to preferentially distribute dry and air supplementing resources to the sub-cabin deviating from the setting and isolate the sub-cabin from other sub-cabin in the air path. When there is a control conflict in the double closed loop, controller (4) switches the priority according to the operation mode: in the door opening and personnel entering and exiting mode, the micro-positive pressure is preferentially maintained at not less than a first set threshold, and in the closed steady state mode, the dew point difference is preferentially met, and the micro-positive pressure is maintained at not less than a second set threshold.

2. The micro-positive pressure-dew point double closed loop and sub-division autonomous control system for the Sagaris energy station according to claim 1, characterized in that, Controller (4) includes event feedforward module (4-1), which performs positive pressure feedforward before the door is opened to suppress dust entering, performs a recovery curve of fast drying and slow pressure rise after the door is closed, and actively increases the drying and recirculation capacity under the conditions of outside sandstorm or night rapid cooling warning.

3. The micro-positive pressure-dew point double closed loop and sub- compartment autonomous control system for the Sagaris energy station according to claim 1, characterized in that, Controller (4) estimates the equivalent leakage rate by step pressurization and pressure maintenance test on the sub-cabin using self-checking pressurization / maintenance module (4-2), and accordingly adaptively corrects the micro-positive pressure target, drying load and maintenance period, and triggers the degraded operation of the sub-cabin when the leakage rate exceeds the threshold while keeping other sub-cabin online.

4. The micro-positive pressure-dew point double closed loop and sub- compartment autonomous control system for the Sagaris energy station of claim 1, wherein, Cabin dew point sensor group (2-2) is arranged at the upper part of the sub-cabin and the door area, and the controller performs consistency test on multiple dew points and uses robust estimation for the dew point difference ring to reduce the deviation caused by local cold and hot spots or air flow dead angle.

5. The micro-positive pressure-dew point double closed loop and sub- compartment autonomous control system for the Saguaro Energy Station of claim 1, wherein, ​ 6. The micro-positive pressure-dew point double closed loop and sub- compartment autonomous control system for the Saguaro Energy Station of claim 1, wherein, The air supplementing fan (2-3) and the recirculation fan (2-4) are provided with dustproof and check structure (2-7), including labyrinth dustproof and breathing membrane structure, normal state meets IP6X, and in the cabin isolation state, cross flow between cabins is prevented by one-way check.

7. The micro-positive pressure-dew point double closed loop and sub- compartment autonomous control system for the Saguaro Energy Station of claim 1, wherein, The drying unit (2-6) includes at least one of the adsorption drying unit and the membrane drying unit, and realizes cabin metering and two-stage drying through the distribution valve (3-1) and the flow metering unit (3-2), wherein the basic drying load is provided by the membrane, and the peak drying load is provided by the adsorption.

8. A control method of the system according to any one of claims 1 to 7, characterized by, It includes: The differential pressure and dew point inside and outside the cabin are collected, and the micro-positive pressure ring and the dew point difference ring are constructed in parallel closed loop; the positive pressure feedforward is executed before the door opening event, and after the door is closed, the recovery sequence of rapid drying and slow pressure rise is executed until the two rings meet the standard at the same time; when any cabin deviates from the setting, the drying / air supplementing resource is preferentially allocated to the cabin and the air path is isolated when needed, and the non-fault cabin is maintained online; the step pressure self-checking is periodically executed to estimate the leakage rate, and the setting and maintenance strategy are adjusted accordingly; When sandstorm or rapid cooling at night occurs outside, the drying and recirculation capacity is improved, and after reaching stability, it is restored to the energy-saving working condition.

Images