Self-adaptive regulation and control method and system for mine main ventilator under time sequence

Abstract

The invention belongs to the technical field of mine intelligent ventilation, and particularly discloses a self-adaptive regulation and control method and system for a mine main ventilator under a time series, and the method comprises the following steps: S1, monitoring ventilation parameters and environment parameters which dynamically change underground in real time; s2, constructing a real-time wind network resolving model, and performing coordinate analysis on the motion trail of the operation condition point of the fan under the time sequence; s3, determining whether the operation condition point of the fan is within the tolerance reliable range or not; s4, a real-time air flow regulation and control model is constructed, and the optimal solution of the fan regulation and control scheme is achieved; and S5, based on the optimal solution, a control signal is issued to a frequency converter of the main ventilator, and the fan is regulated and controlled in a self-adaptive mode. By adopting the technical scheme, the operation state of the fan is intelligently adjusted according to the real-time mine environment change, the tolerance range of fan operation is introduced into the optimal solution strategy of the regulation and control scheme, airflow turbulence caused by excessive adjustment of fan parameters is avoided, and the safety, efficiency and stability of a ventilation system are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of mine intelligent ventilation, and relates to a method and system for adaptively controlling a main ventilation fan of a mine under a time series. Background Art

[0002] With the advancement of smart mines, the mechanized production speed of mines has increased significantly, and high-speed production will inevitably lead to the expansion of mining scale. This expansion not only requires the air supply efficiency of the main fan to be improved to cope with the expanded production control area, but also causes the ground stress and surrounding rock stability of the shaft and tunnel to change dynamically under the disturbance of rock mass self-weight stress and mining field stress, thereby changing the characteristics of the shaft and tunnel wall resistance. The changes in fan efficiency and the changes in the characteristics of shaft and tunnel wall resistance make the fan working conditions and shaft and tunnel resistance present non-constant characteristics. The changing shaft and tunnel resistance and fan static pressure, as energy terms of the Bernoulli equation, will cause the shaft and tunnel ventilation pressure to be redistributed, the distribution weight of the ventilation network air volume will change, and the ventilation parameters (air volume, air pressure, wind speed, etc.) will fluctuate dynamically in the time series. At the same time, the expansion of production scale is manifested in the longitudinal space as an increase in mining depth. Under the joint action of geothermal flow, geological slope and air volume compression effect, a non-steady-state thermal environment field and gradient flow field will be formed inside the high-mining depth mine. The wind flow presents a non-isothermal flow state, and its thermodynamic parameters and kinetic parameters change in a linked manner. That is, in the time and space scale, the ventilation parameters of mine airflow change in conjunction with environmental parameters (temperature, pressure, density, etc.), and the airflow has the characteristics of thermal flow coupling.

[0003] As the core power equipment of the ventilation system, the main fan directly controls the operating stability of the entire ventilation network. Its operating status determines the existence of ventilation parameters, which in turn affects the effect of mine ventilation. If the main fan cannot be adjusted in time according to the dynamically changing mine environment under the time series, it may lead to uneven ventilation, turbulent wind flow in local areas, and even the risk of insufficient air supply or accumulation of harmful gases. Therefore, the performance and operating status of the main fan play a decisive role in the efficiency and safety of mine ventilation.

[0004] Traditional methods for controlling the main ventilation fans in mines usually rely on setting fixed parameters, such as setting a certain fan frequency and blade angle value according to a decision-making plan to ensure stable operation of the fan. However, this control method fails to take into account the changes in the mine environment and wind flow conditions under time series, especially the fluctuations in ventilation parameters and environmental parameters. This makes it impossible for traditional methods to achieve flexible fan adjustment when facing non-steady-state environments or emergencies in mines, which often leads to low fan efficiency, energy waste, and even system failures. It is imperative to conduct adaptive control of fans based on the dynamic environment of mines.

[0005] The mine environment itself is complex and unstable, affected by various factors such as ground climate, altitude gradient, roadway layout, etc. This requires the fan to be dynamically adjusted based on real-time mine environment data to ensure the ventilation effect of the entire mine. However, it is not only unrealistic but also extremely dangerous to frequently adjust the fan for all environmental changes. Excessive and frequent adjustment of the blade angle and frequency of the fan may lead to chaotic airflows and even phenomena such as reverse airflows, which will pose great hidden dangers to the safe production of the mine. Summary of the Invention

[0006] The purpose of the present invention is to provide a self-adaptive regulation method and system for the main mine ventilation fan under time series, improving the safety, efficiency and stability of the ventilation system.

[0007] To achieve the above purpose, the basic solution of the present invention is: A self-adaptive regulation method for the main mine ventilation fan under time series, including the following steps:

[0008] S1, Real-time monitor the ventilation parameters and environmental parameters that change dynamically underground;

[0009] S2, By analyzing the dynamic change law of the environmental parameters of the mine air current under time series, construct a transient heat flow characteristic model of the air current and a model of fluctuating natural wind pressure and ventilation resistance, and solve the fluctuation values of natural wind pressure and ventilation resistance under time series;

[0010] Take the fluctuation values of natural wind pressure and ventilation resistance under time series as the iterative initial values, construct a real-time wind network calculation model, and analyze the movement trajectory of the fan operating condition point under time series in a coordinate manner;

[0011] S3, Based on the fan reliable operation interval data, combined with the movement condition point, determine whether the fan operation condition point is within the tolerable reliable range. If so, execute step S1; otherwise, execute step S4;

[0012] S4, Take the fluctuating natural wind pressure and ventilation resistance as environmental variables, the adjustment resistance of the roadway as the decision variable, and the minimum system power consumption as the objective function, construct a real-time air current regulation model, and realize the optimal decision-making for the fan regulation plan;

[0013] S5, Based on the optimal decision-making, send a control signal to the frequency converter of the main ventilation fan to adaptively regulate the fan.

[0014] The working principle and beneficial effects of this basic solution are as follows: This technical solution monitors the ventilation parameters and environmental parameters that change dynamically underground in real time, and uses them as data sources to substitute into the wind network calculation model and the air flow regulation model. It can automatically decide the optimal solution for adjusting the operating state of the fan according to the real-time working conditions, without relying on set fixed parameters. This adaptive regulation ability greatly improves the response ability of the fan to changes in the mine environment, and avoids the problems of low efficiency caused by fixed parameters or the inability to cope with sudden changes in ventilation requirements in traditional methods.

[0015] The present invention introduces a tolerance range for the operation of the fan to ensure that when the mine environment changes, adjustment is only made when the working conditions exceed the reliable working area, avoiding air flow disorder and potential safety hazards caused by excessive adjustment. Compared with the prior art, this tolerance mechanism effectively reduces the frequent adjustment of the fan and improves the safety and stability of the mine ventilation system.

[0016] Furthermore, the transient thermal flow characteristic model of the air flow is:

[0017]

[0018] The fluctuating natural ventilation pressure and ventilation resistance model:

[0019]

[0020] h i-r (t)′ = ((ρ i (t) / ρ i )α i L i U i / S i 3 )q i 2 = (ρ i (t) / ρ i )R i q i 2 = R i (t)′q i 2

[0021] Among them, t is time; ρ is the air flow density; T is the air flow temperature; P is the air flow pressure; is the relative humidity of the air flow; P sa is the absolute partial pressure of saturated water vapor; Rdry and Rhumid are the gas constants of dry air and water vapor respectively, with the values R dry = 287.04, R humid = 461.39; h N(t)' is the corrected fluctuating natural mine air pressure; m is the number of control airways with end nodes at different heights; P in (t) is the starting pressure value of the downward air current; P out (t) is the starting pressure value of the upward air current; Z is the vertical height difference of the roadway; j is the air roadway number of the downward air current, j ∈ {1, 2, 3, …, i}; k is the air roadway number of the upward air current, k ∈ {1, 2, 3, …, i}; g is the acceleration of gravity; P j (t) is the air density in airway j; ρ k (t) is the air density in airway k, h i-r (t)' is the corrected fluctuating ventilation resistance of roadway i; ρ i is the air density of the air current flowing through roadway i; α i is the friction resistance coefficient of roadway i; L i is the length of roadway i; U i is the perimeter of the cross-section of roadway i; S i is the cross-sectional area of roadway i; q i is the air quantity flowing through roadway i; R i is the friction air resistance of roadway i, N·s 2 / m 8 ; R i (t)' is the fluctuating friction air resistance of roadway i; ρ i (t) is the change value of the air density of the air current in roadway i.

[0022] Since the air current has the characteristics of a continuous medium when flowing in the ventilation system, fluctuating corrections to the natural mine air pressure and ventilation resistance of a single roadway in the time series will inevitably cause a chain reaction in a large number of related roadways affected by the fluctuating corrected roadways (or fans), thereby causing fluctuations in the air quantity of the entire air network. To synchronously map the dynamic continuous operation state of the ventilation system, based on the law of air pressure balance, the corrected hN(t)' and Ri'(t) fluctuation values are used as the iterative initial values, and the continuous time is used as the distribution times to construct a wind network solution model in the time series, and the cross algorithm is used to complete the reverse iteration to calculate the air quantity qi(t) (unit: m3 / s) of each branch in the wind network in the time series.

[0023] Taking the operating point that can reflect the characteristics of ventilation power and underground network linkage as the observable quantity, using the dynamic operating condition fluctuation movement trajectory to represent the change in the air quantity of the network q i (t)' caused by the correction of ventilation resistance and natural mine air pressure, and the negative feedback effect of the change in q i (t)' on the change in ventilation resistance and natural mine air pressure, to achieve an accurate description of the dynamic behavior of the entire ventilation system. The transient calculation formula for the position coordinates of the operating point is proposed.

[0024] Furthermore, the real-time wind network solution model is:

[0025]

[0026] Among them, q(t)' is the branch air volume vector; C is the basic loop matrix; q y (t)' is the co-tree branch air volume vector; R(t)' is the branch air resistance column vector; diag is a subscript indicating a diagonal matrix composed of vectors; H f is the fan air pressure column vector; H N (t)' is the fluctuating natural air pressure column vector;

[0027] The transient calculation formula for the working condition observation position coordinates S(X, Y) is proposed:

[0028] S(X, Y) = S(Q(t)', h N (t)' + a0 + a1Q(t)' + a2(Q(t)')[[]] 2 )

[0029] Among them, the fan working air volume is Q(t)'; hN(t)' is the fluctuating natural air pressure, and a0, a1, and a2 are fan characteristic coefficients.

[0030] The real-time wind network solution model has a simple structure and is convenient to use.

[0031] Furthermore, the real-time air flow regulation model is:

[0032]

[0033] Among them, under the time series, h i (t) is the ventilation pressure of roadway i; Δh i (t) is the adjustment resistance of roadway i; h N (t) is the ventilation pressure of roadway N; q i (t)' is the branch air volume vector of roadway i; v is the number of mine roadways; B is the basic incidence matrix; G is the branch mass flow vector; C is the basic loop matrix; H r (t)' is the branch fluctuating ventilation resistance column vector; H f is the fan air pressure column vector; H N (t)' is the fluctuating natural air pressure column vector.

[0034] Based on the real-time air flow regulation model, a ventilation network intelligent decision analysis program is connected to realize the optimal decision-making of the fan regulation plan.

[0035] Furthermore, according to the characteristic curve of the mine main fan, the floating range of the fan air volume, the 90% maximum working air pressure curve, and the 60% efficiency curve under the blade angle are defined, and the area between the four curves is defined as the reliable working area of the fan;

[0036] When the operating point is within this reliable operating area, the fan operation is considered reliable and no adjustment operation is required.

[0037] Based on the data of the reliable operating range of the fan, the stable regulation of the fan is carried out.

[0038] The present invention also provides an adaptive regulation system for the main mine ventilator under time series, including a multi-parameter fusion monitoring sensor unit, a decision-making and control platform, and a MySQL database;

[0039] The multi-parameter fusion monitoring sensor unit is used to monitor the ventilation parameters and environmental parameters that change dynamically underground in real time. The output end of the multi-parameter fusion monitoring sensor unit is connected to the input end of the decision-making and control platform;

[0040] The decision-making and control platform accesses the MySQL database to store the data of the reliable operating range of the fan. The decision-making and control platform outputs a control signal according to the method of the present invention to control the operation of the controller of the frequency converter of the main ventilator.

[0041] This system realizes the precise adjustment of the fan through real-time data acquisition and analysis, ensuring the efficient and safe operation of the fan.

[0042] Further, the multi-parameter fusion monitoring sensor unit includes a wind speed sensor, a differential pressure sensor, a temperature and humidity multi-parameter sensor, a monitoring sub-station and a power supply;

[0043] The wind speed sensor and the temperature and humidity multi-parameter sensor are arranged in the main intake airways and all return airways of the mine ventilation system, and the installation positions are all higher than the center line of the roadway section. A pair of differential pressure sensors are installed in front of and behind all air doors in the mine;

[0044] The monitoring sub-station and the power supply are arranged near the set points of the wind speed sensor, the differential pressure sensor, and the temperature and humidity multi-parameter sensor. The wind speed sensor, the differential pressure sensor, and the temperature and humidity multi-parameter sensor are connected to the monitoring sub-station, and the collected data of various sensors are matched and fused through a data fusion algorithm. The power supply is connected to the monitoring sub-station.

[0045] By combining the wind speed sensor, the differential pressure sensor, and the temperature and humidity multi-parameter sensor, a multi-parameter fusion monitoring sensor network that can realize the real-time monitoring of ventilation parameters and environmental parameters is formed to collect the required parameters.

[0046] Further, it also includes a display module, and the input end of the display module is connected to the output end of the decision-making and control platform.

[0047] The decision signal output by the decision-making and control platform is displayed for easy viewing.

[0048] The present invention also provides a ventilation system, which includes an inlet air collector, a front main body cylinder, a Class-I explosion-proof motor, a first-stage impeller, a second-stage impeller, a rear main body cylinder, a Class-II explosion-proof motor, a diffuser, a diffuser tower, and the mine main ventilation fan adaptive control system according to the time series of the present invention;

[0049] The inlet air collector is arranged at the front end of the front main body cylinder, the rear end of the front main body cylinder is connected to one end of the rear main body cylinder, and the diffuser and the diffuser tower are sequentially connected to the other end of the rear main body cylinder;

[0050] The Class-I explosion-proof motor and the first-stage impeller are arranged inside the front main body cylinder, and the output shaft of the Class-I explosion-proof motor is connected to the first-stage impeller;

[0051] The second-stage impeller and the Class-II explosion-proof motor are both placed inside the rear main body cylinder, the output shaft of the Class-II explosion-proof motor is connected to the second-stage impeller, and the first-stage impeller and the second-stage impeller are arranged oppositely.

[0052] The ventilation system has a simple structure. Based on the mine main ventilation fan adaptive control system according to the time series, the efficient and safe operation of the fan is realized. Description of the Drawings

[0053] Figure 1 It is a schematic diagram of the characteristic curve of the mine main ventilation fan of the mine main ventilation fan adaptive control method according to the time series of the present invention;

[0054] Figure 2 It is a schematic diagram of the installation structure of the multi-parameter fusion monitoring sensor unit of the mine main ventilation fan adaptive control system according to the time series of the present invention;

[0055] Figure 3 It is a schematic diagram of the structure of the multi-parameter fusion monitoring sensor unit of the mine main ventilation fan adaptive control system according to the time series of the present invention;

[0056] Figure 4 It is a schematic diagram of the structure of the mine main ventilation fan adaptive control system according to the time series of the present invention;

[0057] Figure 5 It is a schematic diagram of the axial flow fan structure of the ventilation system of the present invention.

[0058] The reference numerals in the drawings of the specification include: inlet air collector 25, front main body cylinder 26, Class-I explosion-proof motor 27, first-stage impeller 28, second-stage impeller 29, rear main body cylinder 30, Class-II explosion-proof motor 31, diffuser 32, diffuser tower 33, motor base 34, junction box 35. Detailed Embodiments

[0059] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0060] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0061] In the description of the present invention, unless otherwise specified and defined, it should be noted that the terms "mounted", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or the communication inside two elements. It can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific situations.

[0062] Existing research generally defaults that the air flow in the mine is a power flow and regards the flow of the air flow as an isochoric process characterized by a constant density. However, in an actual mine, there is unsteady heat and mass transfer between the underground air flow in the gradient flow field and the atmospheric and underground environmental fields formed under the action of factors such as atmospheric temperature and geothermal heat flow. This will cause dynamic changes in environmental parameters (density, pressure, temperature, etc.) and ventilation parameters (wind speed, air volume, wind pressure, etc.). That is, the essence of the mine air flow process is a variable heat flow process of air dynamic coupling thermal action.

[0063] The dynamically changing environmental parameters and ventilation parameters will cause continuous fluctuations in the natural wind pressure and ventilation resistance. Then, the air volume calculated by the traditional wind network calculation model constructed with fixed ventilation resistance and natural wind pressure is a fixed value, rather than fluctuating in the time series, so it is inaccurate. Similarly, the traditional air flow regulation model is constructed with natural wind pressure, ventilation resistance and air volume as constant values. Then, it will not be able to determine the optimal solution set of air flow regulation, and thus it is impossible to achieve precise regulation of the air volume in the ventilation network.

[0064] The present invention discloses an adaptive regulation method for a mine main ventilator under a time series, realizing intelligent adaptive regulation of the air flow under the conditions of a mine unsteady environmental field. The adaptive regulation method for a mine main ventilator under a time series includes the following steps:

[0065] S1. Monitor in real time the ventilation parameters (such as wind speed, air pressure, humidity, etc.) and environmental parameters (such as density, temperature, pressure, etc.) that change dynamically underground.

[0066] S2. By analyzing the dynamic change rules of the environmental parameters of the mine air flow under the time series, construct a transient heat flow characteristic model of the air flow and a model of fluctuating natural air pressure and ventilation resistance, and solve the fluctuation values of the natural air pressure and ventilation resistance under the time series.

[0067] Take the fluctuation values of the natural air pressure and ventilation resistance under the time series as the iterative initial values, construct a real-time wind network solution model, and analyze the movement trajectory of the fan operating condition point under the time series in a coordinate manner.

[0068] S3. Based on the reliable operating range data of the fan, combined with the movement condition point, determine whether the fan operating condition point is within the tolerable and reliable range. If it is, execute step S1; otherwise, execute step S4. The tolerable range of the fan operation is introduced into the optimal decision-making strategy of the regulation plan to avoid the air flow disorder caused by excessive adjustment of the fan parameters.

[0069] The main function of the fan is to supply air underground in the coal mine, and its performance is usually described by the characteristic equation of the fan: h = a0 + a1q + a2q 2 where h represents the working air pressure of the fan, a0, a1, a2 are characteristic coefficients, and q is the working air volume of the fan. According to this equation, the operating state of the fan can be characterized by the characteristic curve. At the same time, there is a quadratic proportional relationship between the air volume and air pressure underground in the coal mine, which can usually be expressed by the following resistance relationship: H = RQ 2 where H is the underground resistance value and Q is the total return air volume underground.

[0070] Since the main function of the fan is to supply air underground in the coal mine, the air pressure provided by the fan should be equal to the ventilation resistance consumed by the underground system, and the air volume of the fan should be equal to the return air volume underground. Based on this, combining the fan characteristic equation and the underground resistance equation, the following relationship can be obtained:

[0071] h = a0 + a1q + a2q 2 = H = RQ 2

[0072] The solution (h, q) of this equation is the operating condition point of the fan. Specifically, the operating condition point is the intersection of the fan characteristic curve and the underground air volume-air pressure relationship curve. The air pressure and air volume values corresponding to this intersection point are the fan operating states under the actual operating conditions. In the time series, due to the real-time fluctuation characteristics of the air volume, it means that the operating condition point of the fan will also change dynamically accordingly. Therefore, it is necessary to continuously update the coordinates of the operating condition point through real-time wind network solution. That is, the operating condition point under the time series does not have a fixed value, but is dynamically adjusted with the fluctuations of the underground air volume and system resistance.

[0073] S4. Taking the fluctuating natural wind pressure and ventilation resistance as environmental variables, the regulating resistance of the roadway (the result calculated by the air flow regulation model is the regulating resistance allocated to the roadway) as the decision variable, and the minimum system power consumption as the objective function, a real-time air flow regulation model is constructed to achieve the optimal decision-making for the fan regulation scheme;

[0074] S5. Based on the optimal decision-making, a control signal is sent to the frequency converter of the main ventilator to adaptively regulate the fan.

[0075] The sensor network is used to monitor the dynamically changing ventilation parameters and environmental parameters underground in real time. Based on this as the data source, the fluctuations of the natural wind pressure and ventilation resistance are corrected. The corrected fluctuating ventilation resistance and natural wind pressure are substituted into the wind network calculation model for real-time air volume calculation and the solution of the operating point coordinates. According to the calculated operating point coordinates, it is judged whether they are within the tolerable range to determine whether air flow regulation is required. If the operating point exceeds the tolerable range, the system will start the regulation mechanism. During this process, the fluctuating natural wind pressure, ventilation resistance and air volume will be substituted into the air flow regulation model for the decision-making of the optimal regulation scheme. Finally, the regulation decision will be applied to the fan frequency modulation to achieve the dynamic adjustment of the underground air supply.

[0076] In a preferred embodiment of the present invention, the transient thermal flow characteristic model of the air flow is:

[0077]

[0078] Fluctuating natural wind pressure and ventilation resistance model:

[0079]

[0080] h i-r (t)′ = ((ρ i (t) / ρ i )α i L i U i / S i 3 )q i 2 = (ρ i (t) / ρ i )R i q i 2 = R i (t)′q i 2

[0081] Among them, t is time; ρ is the air flow density; T is the air flow temperature; P is the air flow pressure; is the relative humidity of the air flow; Psa is the absolute partial pressure of saturated water vapor; Rdry and Rhumid are the gas constants of dry air and water vapor respectively, with values R dry = 287.04, R humid = 461.39; m is the number of control airways with end nodes at different heights; P in (t) is the starting pressure value of the downward air current; P out (t) is the starting pressure value of the upward air current; Z is the vertical height difference of the roadway; j is the airway number of the downward air current, j ∈ {1, 2, 3, …, i}; k is the airway number of the upward air current, k ∈ {1, 2, 3, …, i}; g is the acceleration due to gravity; P j (t) is the air density in airway j; ρ k (t) is the air density in airway k, R i is the frictional air resistance of roadway i, N·s 2 / m 8 ;

[0082] h N (t)' is the corrected fluctuating natural ventilation pressure, Pa; h i-r (t)' is the corrected fluctuating ventilation resistance of roadway i; ρ i (t) is the change value of the air density in roadway i; R i (t)' is the fluctuating frictional air resistance of roadway i; hi-r(t)' is the corrected fluctuating ventilation resistance of roadway i, Pa; ρ i is the density of the air flowing through roadway i, Kg / m 3 ; α i is the frictional resistance coefficient of roadway i, kg·m 3 ; L i is the length of roadway i, m; U i is the perimeter of the cross-section of roadway i, m; S i is the cross-sectional area of roadway i, m 2 ; q i is the air volume flowing through roadway i, m 3 / s; R i (t)' is the fluctuating frictional air resistance of roadway i, N·s 2 / m 8 .

[0083] Take the corrected natural ventilation pressure fluctuation value and frictional air resistance fluctuation value as the iterative initial values, and use continuous time as the number of distribution times to construct a wind network solution model under the time series.

[0084] Take the fluctuating natural ventilation pressure and ventilation resistance as environmental variables, the regulating resistance as the decision variable, and the minimum system power consumption as the objective function to construct a corrected air current regulation model based on the thermal-fluid coupling characteristics of the air current. The branches and airways mentioned in the text refer to roadways.

[0085] In a preferred embodiment of the present invention, the real-time air network calculation model is as follows:

[0086]

[0087] where q(t)′ is the branch air volume vector; C is the basic loop matrix; q y (t)′ is the co-tree branch air volume vector; R(t)′ is the branch air resistance column vector; diag is a subscript indicating a diagonal matrix composed of vectors; H f is the fan air pressure column vector; H N (t)′ is the fluctuating natural air pressure column vector;

[0088] The transient calculation formula for the observation position coordinates S(X, Y) of the proposed working condition is presented:

[0089] S(X, Y) = S(Q(t)′, h N (t)′ + a0 + a1Q(t)′ + a2(Q(t)′) 2 )

[0090] where the fan working air volume is Q(t)′; h N (t)′ is the fluctuating natural air pressure, and a0, a1, and a2 are fan characteristic coefficients.

[0091] In a preferred embodiment of the present invention, the real-time air flow regulation model is as follows:

[0092]

[0093] where, in the time series, h i (t) is the ventilation pressure of roadway i; Δh i (t) is the regulation resistance of roadway i; h N (t) is the ventilation pressure of roadway N; q i (t)′ is the branch air volume vector of roadway i; v is the number of mine roadways; B is the basic incidence matrix; G is the branch mass flow vector; C is the basic loop matrix; H r (t)′ is the branch fluctuating ventilation resistance column vector; H f is the fan air pressure column vector; H N (t)′ is the fluctuating natural air pressure column vector.

[0094] In a preferred embodiment of the present invention, as Figure 1 shown, according to the characteristic curve of the mine main fan, the fan air volume floating range (tolerable air volume floating lower curve, tolerable air volume floating upper curve), 90% maximum working air pressure curve, and 60% efficiency curve at the blade angle are defined. The area between the four curves is delimited as the reliable working area of the fan, specifically [0.9Q, 1.1Q].

[0095] When the operating point is within this reliable operating range, the fan is considered to be operating reliably and no adjustment operations are required. When the operating point exceeds the tolerance range of the fan's reliable operating range, the adjustment mechanism will be triggered, and a suitable fan frequency adjustment scheme will be determined based on the intelligent decision-making analysis program for the ventilation network.

[0096] Assume that the required air volume in the mine is Q (i.e., the fan air volume). Defining the air volume floating range as [0.9Q, 1.1Q] is determined based on the safety and stability considerations during the actual operation of the mine and combined with engineering application experience. During the operation of the fan, usually the air volume demand may fluctuate due to environmental factors or changes in operating conditions. However, if the fan is adjusted as long as the Q value is not met, it will cause disorder in the underground air flow. Setting the tolerance range of the air volume as [0.9Q, 1.1Q] can ensure that even if there are small fluctuations in the fan air volume, it will not have a significant impact on the ventilation effect and can maintain the safety of the mine environment.

[0097] For the case of an air volume of 1.1Q, although there is a certain amount of energy waste, this situation will not affect the safe operation of the fan, and providing more air volume helps to ensure the stability of ventilation and avoid unnecessary vibrations or instability of the fan due to too low a load. Therefore, this kind of fluctuation is acceptable.

[0098] As for the case of an air volume of 0.9Q, although the provided air volume is slightly lower than the target value Q, there are usually multiple ventilation openings and ventilation channels in the mine. Even if the air volume is slightly lower than Q, it can be supplemented by the natural air pressure of the mine or other ventilation devices to ensure that the ventilation is not affected too much. Only in specific situations (such as when there are special gas emissions or fires in the working area and other emergency situations), precise control of the air volume is required. Therefore, an air volume of 0.9Q can still meet the ventilation requirements in most cases.

[0099] When the air volume fluctuation range is limited to [0.9Q, 1.1Q], if within this range, the fan does not need to be adjusted. In this case, based on the working characteristic curve of the fan at the current blade angle h = a0 + a1Q + a2Q 2 The working curves of the fan within the acceptable fluctuation range can be derived as follows:

[0100] h1 = a0 + 0.9a1Q + 0.81a2Q 2

[0101] h2 = a0 + 1.1a1Q + 1.21a2Q 2

[0102] In practical engineering applications, when the air supply pressure of the fan reaches 90% of the maximum working pressure that can be provided at the current blade angle, it indicates that the fan at the current blade angle can no longer provide the air volume required underground. At this time, it is necessary to adjust the blade angle or frequency. On the contrary, when the air supply efficiency of the fan is lower than 60%, it means that the air volume provided by the fan at the current blade angle is much larger than the air volume required underground, and the operating efficiency of the fan is relatively low. In this case, it is necessary to adjust the blade angle or frequency to optimize the operation of the fan. By visualizing the working curve, 90% maximum working pressure line, and 60% efficiency curve of the fan within an acceptable fluctuation range, four intersecting curves can be obtained, forming a closed quadrilateral area, which is the reliable working area of the fan. In addition, "defining the air volume fluctuation range of the fan at a certain blade angle....." means that when adjusting the fan, the frequency is selected instead of adjusting the blade angle, and the blade angle remains unchanged all the time, mainly considering the operating efficiency and stability of the main mine fan. First of all, adjusting the blade angle will cause the operation of the underground ventilation system to be unstable. Especially when the load is low, the fan may experience unnecessary vibrations, and the air flow in the underground ventilation system may become chaotic. Adjusting the frequency (i.e., adjusting the rotational speed of the fan) can change the air volume output more smoothly and can control the performance of the fan more precisely. The advantage of adjusting the frequency compared to adjusting the blade angle is that the frequency modulation technology can achieve more precise air volume adjustment, has less impact on the mechanical load of the fan, and avoids the wear and potential failure risks of the internal structure of the fan caused by frequent adjustment of the blade angle. At the same time, the frequency modulation system can usually utilize electric power resources more efficiently and reduce energy waste. Therefore, while ensuring the stability and safety of mine ventilation, the frequency modulation method has higher adaptability and economy.

[0103] The present invention also provides an adaptive control system for the main mine ventilator under a time series, as Figure 4 shown, which includes a multi-parameter fusion monitoring sensor unit, a decision-making and control platform, and a MySQL database.

[0104] The multi-parameter fusion monitoring sensor unit is used to monitor the ventilation parameters and environmental parameters that change dynamically underground in real time. The output end of the multi-parameter fusion monitoring sensor unit is electrically connected to the input end of the decision-making and control platform. For example, by directly connecting the multi-parameter fusion monitoring sensor network (multi-parameter fusion monitoring sensor unit) arranged underground using a transmission cable and a signal converter, real-time monitoring of the ventilation parameters and environmental parameters that change dynamically underground can be achieved.

[0105] The decision-making and control platform can be set up relying on a computer. The decision-making and control platform accesses the ventilation network operation status reconstruction analysis program to analyze the movement trajectory of the fan operation working condition point in the time series in a coordinate manner. The underlying mathematical logic of this program is the wind network calculation model. The decision-making and control platform accesses the MySQL database to store the data of the reliable operation range of the fan, so as to combine the movement working condition point to make a real-time decision on the necessity of fan regulation.

[0106] The decision-making and control platform accesses the ventilation network intelligent decision-making analysis program to achieve the optimal decision-making on the fan regulation plan. The underlying mathematical logic of this program is the air flow regulation model. The decision-making and control platform outputs a control signal according to the method described in the present invention to control the controller of the frequency converter of the main ventilation fan. The decision-making and control platform directly connects to the frequency converter arranged on the main ventilation fan by using a transmission cable and a signal converter to achieve the adaptive regulation of the fan.

[0107] Compared with the prior art, the present invention mainly takes the dynamically changing mine environment as an influencing factor for the fan regulation decision-making, and at the same time updates the optimal decision-making strategy for the fan regulation plan. Through intelligent decision-making and tolerance control, it avoids the air flow disorder and safety hazards caused by frequent adjustment, ensures the efficient and stable operation of the fan, and improves the energy use efficiency at the same time.

[0108] In a preferred embodiment of the present invention, as Figure 2 and Figure 3 shown, the multi-parameter fusion monitoring sensor unit includes a wind speed sensor, a differential pressure sensor, a temperature and humidity multi-parameter sensor, a monitoring sub-station and a power supply.

[0109] The wind speed sensor and the temperature and humidity multi-parameter sensor are arranged in the main intake airway and all return airways of the mine ventilation system, and the installation positions are all higher than the center line of the roadway section. A pair of differential pressure sensors are installed in front of and behind all air doors in the mine.

[0110] The monitoring sub-station and the power supply are arranged near the set points of the wind speed sensor, the differential pressure sensor and the temperature and humidity multi-parameter sensor. The wind speed sensor, the differential pressure sensor and the temperature and humidity multi-parameter sensor are electrically connected to the monitoring sub-station. All sensors are connected to the monitoring sub-station by a wired method, and the collected data of various sensors are matched and fused through a data fusion algorithm to improve the accuracy and reliability of the data. The power supply is electrically connected to the monitoring sub-station.

[0111] The monitoring sub-station underground is a centralized data collection and management site. Its main function is to collect the sensor data of each monitoring point in the mine to a unified terminal. Various sensors, such as temperature, humidity, air pressure, wind speed, coal dust concentration, gas concentration, etc., are installed at different positions in the mine to monitor various safety indicators of the mine environment in real time. The data of these sensors are transmitted to the monitoring sub-station, and the sub-station is responsible for collecting, processing and storing these data.

[0112] The specific content of the data fusion algorithm involves comprehensively processing data from different sensors to improve the accuracy and reliability of the data. Due to the complexity of the mine environment, various sensors may be affected by noise or external interference. Therefore, the goal of data fusion is to filter, correct, and fuse the collected data through algorithms to obtain more accurate and stable monitoring results. Specifically, the algorithm will match the data of different sensors such as wind speed, differential pressure, temperature, and humidity in terms of time and space, eliminate inconsistencies, and correct outliers. In this way, the system can provide more accurate real-time data to help mine managers make better decisions.

[0113] The purpose of the data fusion algorithm is to effectively integrate data from different sensors to improve the accuracy and robustness of the monitoring system. In the mine environment, the measurement results of different sensors may vary or have errors. Therefore, it is necessary to process these data through the data fusion algorithm to remove redundant information, correct biases, and integrate multi-source data into more reliable monitoring results. Sensor sub-stations and supporting power supplies are set near the installation points of wind speed sensors, differential pressure sensors, and multi-parameter sensors to form a multi-parameter fusion monitoring sensor network that can realize real-time monitoring of ventilation parameters and environmental parameters.

[0114] The multi-parameter fusion monitoring sensor network (i.e., the multi-parameter fusion monitoring sensor unit) is connected to a signal converter, which converts the real-time monitored ventilation parameters and environmental parameters from analog signals into digital signals. The signal converter is connected to the decision and control platform through a transmission cable to realize the real-time transmission of the parameters to the platform in the form of digital signals.

[0115] System integration includes the mutual cooperation of modules such as data acquisition, signal transmission, and decision-making platform. Through the above technical solutions, the adaptive regulation of the main mine fan is completed. The entire system realizes the precise adjustment of the fan through real-time data acquisition and analysis to ensure the efficient and safe operation of the fan.

[0116] To ensure the stable operation of the system, the real-time adjustment results of the fan (such as air volume, rotational speed, etc.) are fed back to the intelligent decision-making platform again to form a closed-loop control mechanism. If the fan operation does not reach the expected effect, the system will re-evaluate the fan operating conditions and adjust the regulation strategy in a timely manner.

[0117] In a preferred embodiment of the present invention, the adaptive regulation system of the main mine ventilation fan under the time series further includes a display module. The input end of the display module is electrically connected to the output end of the decision and control platform. The display module can adopt a display, and a control switch for controlling the fan can also be set thereon.

[0118] The present invention also provides a ventilation system, such as Figure 5As shown in the figure, it includes an inlet air collector 25, a front main body cylinder 26, a Class I explosion-proof motor 27, a first-stage impeller 28, a second-stage impeller 29, a rear main body cylinder 30, a Class II explosion-proof motor 31, a diffuser 32, a diffuser tower 33 (belonging to the axial flow fan structure) and the adaptive control system for the main mine ventilator under the time series described in the present invention.

[0119] The inlet air collector 25 is arranged at the front end of the front main body cylinder 26. The rear end of the front main body cylinder 26 is connected to one end of the rear main body cylinder 30. The diffuser 32 and the diffuser tower 33 are sequentially connected to the other end of the rear main body cylinder 30. The Class I explosion-proof motor 27 and the first-stage impeller 28 are arranged inside the front main body cylinder 26. The output shaft of the Class I explosion-proof motor 27 is connected to the first-stage impeller 28.

[0120] The second-stage impeller 29 and the Class II explosion-proof motor 31 are both placed inside the rear main body cylinder 30. The output shaft of the Class II explosion-proof motor 31 is connected to the second-stage impeller 29. The first-stage impeller 28 and the second-stage impeller 29 are arranged oppositely. The Class I explosion-proof motor 27 and the Class II explosion-proof motor 31 are both installed on the motor base 34. A junction box 35 is provided on the outer wall of the front main body cylinder 26. The frequency converter is connected to the explosion-proof motor of the fan through the junction box 35.

[0121] The axial flow fan is composed of structures such as fan blades, air collectors, rectifiers, and diffusers 32. The air collector, which is curved and has a continuously decreasing cross-section, is designed to make the air flow more concentrated, thereby improving the air intake efficiency. The front main cylinder is a streamlined curved conical shell that covers a movable hub. The axial flow fan and the collector form an annular inlet, which can accelerate the air flow faster and reduce losses, thus ensuring a stable speed and pressure when the air enters the impeller inlet.

[0122] The collector and the front streamline can provide reasonable inlet conditions for the fan, helping to improve the performance of the fan. It can increase the overall pressure level and reduce the turbulent loss rate. The diffuser 32 is a unique component of the axial flow fan. It usually consists of a diffuser 32 and a rectifier. Its main function is to reduce the wind speed at the outlet of the axial flow fan. The diffuser 32 housing is composed of a diffuser 32 and sound-absorbing materials. There is a conical fairing inside the diffuser 32 housing. When installing the axial flow fan, it is necessary to install the diffuser 32 at the fan outlet to reduce the speed at the fan outlet and improve the efficiency of the static pressure and the total pressure. The rectifier is used to guide the rotating air flow flowing out automatically to reduce the eddy current loss.

[0123] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0124] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for adaptively controlling a main ventilation fan in a mine under time series, characterized in that: The steps include: S1, real-time monitoring of dynamically changing ventilation parameters and environmental parameters underground; S2, by analyzing the dynamic change law of the environmental parameters of the mine airflow in time series, constructing the transient thermal flow characteristic model of the airflow and the fluctuating natural wind pressure and ventilation resistance model, and solving the fluctuation values ​​of the natural wind pressure and ventilation resistance in time series; The fluctuation values ​​of natural wind pressure and ventilation resistance in the time series are used as the initial values ​​of iteration, a real-time wind network solution model is constructed, and the motion trajectory of the fan operating condition points in the time series is analyzed by coordinate analysis; S3, based on the reliable operation range data of the fan and in combination with the motion operating point, determine whether the fan operating point is within the tolerable reliability range, if so, execute step S1, otherwise, execute step S4; S4, taking the fluctuating natural wind pressure and ventilation resistance as environmental variables, the laneway regulation resistance as the decision variable, and the minimum system power consumption as the objective function, a real-time wind flow control model is constructed to achieve the optimal solution decision for the fan control scheme; S5, based on the optimal solution decision, sends a control signal to the inverter of the main fan to adaptively control the fan.

2. The method for adaptively controlling the main ventilation fan of a mine under time series according to claim 1, characterized in that: The transient heat flow characteristic model of wind flow is: Fluctuating natural wind pressure and ventilation resistance model: h i-r (t)′=((ρ i (t) / p i )a i L i U i / S i 3 )q i 2 =(ρ i (t) / p i )R i q i 2 =R i (t)′q i 2 Where, t is time; ρ is wind flow density; T is wind flow temperature; P is wind flow pressure; is the relative humidity of the wind flow; P sa is the absolute partial pressure of saturated water vapor; Rdry and Rhumid are the gas constants of dry air and water vapor, respectively, and the values ​​are R dry =287.04, R humid =461.39;h N (t)′ is the corrected fluctuating natural wind pressure; m is the number of controlled wind paths with different end nodes at different heights; P in (t) is the pressure value at the starting point of the downward wind flow; P out (t) is the pressure value at the starting point of the upward airflow; Z is the vertical height difference of the roadway; j is the number of the downward airflow path, j∈{1,2,3,…,i}; k is the number of the upward airflow path, k∈{1,2,3,…,i}; g is the gravitational acceleration; P j (t) is the air flow density in air path j; ρ k (t) is the air flow density in air path k, h i-r (t)′ is the corrected fluctuating ventilation resistance of lane i; ρ i is the density of the wind flow through lane i, ρ i (t) is the change value of wind flow density in lane i; α i is the friction coefficient of lane i; L i is the length of lane i; U i is the perimeter of the section of tunnel i; S i is the cross-sectional area of ​​tunnel i; q i is the air volume flowing through lane i; R i is the friction wind resistance of lane i; R i (t)′ is the wave friction wind resistance of lane i.

3. The method for adaptively controlling the main ventilation fan of a mine under time series according to claim 1, characterized in that: The real-time wind network solution model is: Where q(t)′ is the branch air volume vector; C is the basic loop matrix; q y (t)′ is the residual branch wind volume vector; R(t)′ is the branch wind resistance column vector; diag is a subscript, indicating the diagonal matrix composed of vectors; H f is the wind pressure column vector of the fan; H N (t)′ is the column vector of fluctuating natural wind pressure; The transient calculation formula of the working condition observation position coordinate S (X, Y) is proposed: S(X,Y)=S(Q(t)′,h N (t)′+a0+a1Q(t)′+a2(Q(t)′) 2 ) Among them, the fan working air volume is Q(t)′; h N (t)′ is the fluctuating natural wind pressure, and a0, a1, and a2 are the fan characteristic coefficients.

4. The method for adaptively controlling the main ventilation fan of a mine under time series according to claim 1, characterized in that: The real-time wind flow control model is: Among them, in the time series, h i (t) is the ventilation pressure of lane i; Δh i (t) is the regulating resistance of lane i; h N (t) is the ventilation pressure of tunnel N; q i (t)′ is the branch air volume vector of tunnel i; v is the number of mine tunnels; B is the basic association matrix; G is the branch mass flow vector; C is the basic loop matrix; H r (t)′ is the branch wave ventilation resistance column vector; H f is the wind pressure column vector of the fan; H N (t)′ is the column vector of fluctuating natural wind pressure.

5. The method for adaptively controlling the main ventilation fan of a mine under time series according to claim 1, characterized in that: According to the characteristic curve of the mine main fan, the fan air volume floating range under the blade angle, the 90% maximum working air pressure curve and the 60% efficiency curve are defined, and the area between the four curves is defined as the fan's reliable working area; When the operating point is in this reliable working area, it is considered that the fan operation is reliable and no adjustment operation is required.

6. A time series mine main ventilation fan adaptive control system, characterized in that: Includes multi-parameter fusion monitoring sensor unit, decision-making and control platform, and MySQL database; The multi-parameter fusion monitoring sensor unit is used to monitor the dynamically changing ventilation parameters and environmental parameters underground in real time, and the output end of the multi-parameter fusion monitoring sensor unit is connected to the input end of the decision-making and control platform; The decision-making and control platform is connected to the MySQL database to store the fan reliable operation range data. The decision-making and control platform outputs a control signal according to the method described in one of claims 1-5 to control the operation of the controller of the frequency converter of the main fan.

7. The adaptive control system for main ventilation fans in mines under time series according to claim 6, characterized in that: The multi-parameter fusion monitoring sensor unit includes a wind speed sensor, a differential pressure sensor, a temperature and humidity multi-parameter sensor, a monitoring substation and a power supply; The wind speed sensor and temperature and humidity multi-parameter sensor are installed in the main air intake tunnel and all return air tunnels of the mine ventilation system, and the installation position is higher than the center line of the tunnel section. A pair of differential pressure sensors are installed before and after all the air doors in the mine; The monitoring substation and power supply are arranged near the setting points of the wind speed sensor, differential pressure sensor, and temperature and humidity multi-parameter sensor. The wind speed sensor, differential pressure sensor, and temperature and humidity multi-parameter sensor are connected to the monitoring substation, and the power supply is connected to the monitoring substation.

8. The adaptive control system for main ventilation fans in mines under time series according to claim 6, characterized in that: It also includes a display module, the input end of which is connected to the output end of the decision-making and control platform.

9. A ventilation system, characterized in that: It includes an inlet air collector, a front main body cylinder, a Class I explosion-proof motor, a first-stage impeller, a second-stage impeller, a rear main body cylinder, a Class II explosion-proof motor, a diffuser, a diffusion tower, and an adaptive control system for a mine main ventilation fan under the time sequence described in one of claims 6 to 8; The inlet air collector is arranged at the front end of the front main body tube, the rear end of the front main body tube is connected to one end of the rear main body tube, and the diffuser and the diffusion tower are connected to the other end of the rear main body tube in sequence; The Class I explosion-proof motor and the first-stage impeller are arranged in the front main body tube, and the output shaft of the Class I explosion-proof motor is connected to the first-stage impeller; The secondary impeller and the II-level explosion-proof motor are both placed in the rear main body tube, the output shaft of the II-level explosion-proof motor is connected to the secondary impeller, and the primary impeller and the secondary impeller are arranged oppositely.

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