60results about How to "The practical value of the project is good" patented technology

The invention relates to a sliding mode variable structure control method for a low-speed friction servo system which is based on a gray predictor. The method comprises two stages: the first stage, the sliding mode variable structure control method of the exponential approach rate is adopted to control the servo system, simultaneously, the gray control theory is utilized to estimate the uncertain part of the servo system and the outside unknown interference model parameter; the second stage, after former steps, based on the control law at the first stage, the gray predicting compensation control quantity can be calculated according to the estimate parameter, and can take part in controlling the servo system along with the control quantity of the fist stage. The control method can guarantee the low-speed friction servo system to also obtain better robust even though the effects of the uncertain part and the outside unknown interference model parameter are considered, so as to reach high precision tracing effect. The control method has the simple and pellucid program, provides a new control strategy for systems which have nonlinear and uncertain control objects as well as outside unknown interference, thereby having certain practical engineering value.

The invention discloses a discriminating and measuring method for partial discharge modes of a transformer. The method includes: measuring discharge conditions of different discharge modes in a measuring device, acquiring and analyzing measuring results to make spectrums, and calculating fingerprints to form a fingerprint database. For an unknown discharge mode of the transformer, the measuring device is used to acquire and analyze the unknown discharge modes to make a spectrum, calculated fingerprint of the unknown discharge mode can be compared with fingerprint information in the fingerprint database, and accordingly, the partial discharge mode of the transformer can be discriminated. By building up the fingerprint database of the partial discharge of the transformer and using information provided by various discharge spectrums, different discharge modes can be discriminated, and valuable data is provided for fingerprint diagnosis and mode discrimination technology. The method has excellent practical value in engineering, and reliability of the method can reach 99.5%.

A load flow calculation method of a distributed power supply connection power grid comprises the steps that S1. initial data of an electric power system are read; S2. sampling frequency N and the dimensions s of input random variables are determined; S3. an s * N order sampling matrix is generated; S4. sampling frequency is initialized, namely n is equal to 1; S5. whether n is larger than the sampling frequency N is judged, and yes, the probability statistics results of the variables are directly output; otherwise, S6 is carried out; S6. a wind power and photovoltaic power generation output model is determined, and a load random model is determined; S7. a load flow calculation model is determined; S8. an optimized economic model is determined; S9. load flow calculation is carried out; S10. data such as voltage, branch power and power generation cost of a <n>th node group are determined; and S11. a next round of load flow calculation is carried out, t is equal to t + 1, and S5 is carried out. The probability distribution of the output random variables can be estimated well, the uncertainty problem in an electricity market can be well solved, debugging manpower and material resources are saved, and production cost is lowered.

The invention discloses a method for estimating the stability of an anti-inclined slope, which belongs to the technical field of rock and soil engineering and is characterized by comprising the following steps: on the basis of slope geometric dynamic boundary conditions, determining the potential destruction mode of the anti-inclined slope; establishing a uniform expression formula of slope rock block physical quantities, such as equivalent inclination weight, transfer coefficients and the like, which only depend on slope rock block number, and sequentially establishing an inclination destruction stability analysis model of the anti-inclined slope to enable the slope inclination stability analysis to be formulized and programmed. The method is applicable for the condition of oblique crossing of two groups of structural surfaces and expands the applied range of slope inclination stability analysis; and meanwhile, the method is easy for compiling a stability analysis program on the basis of Excel which is widely familiar to engineering technical personnel, and realizes the rapid programmed analysis of the stability of the anti-inclined slope. The invention is applicable for the stability estimation work of the anti-inclined slope in the fields of mines, water conservancy and hydropower, roads and bridges and the like and has good engineering practical value.

The invention provides an optimized dispatching method for a power grid including pumped storage units. The method includes the following steps: step 1, aiming at minimizing the operating costs of allunits, establishing an objective function model; step 2, setting various types of constraint conditions according to the daily actual working conditions of a power grid system including the pumped storage units; step 3, obtaining a mixed integer nonlinear programming model for power grid optimized dispatching according to the objective function model and the various types of constraint conditions, and performing linearization on the nonlinear part of the model to obtain a mixed integer linear programming model for power grid optimized dispatching; and step 4, calling a mathematical optimization toolbox CPLEX solver to solve the mixed integer linear programming model. The dispatching method considers the start-stop costs of each unit and the rotational reserve capacity constraints that canbe provided by the pumped storage units under different operation conditions, also performs linearization on an expression to convert the model into the mixed integer linear programming model, can carry out fast and reliable solution by using a mature solver, and has a good engineering practical value.

The invention discloses a plane multi-port power divider which comprises a plurality of radio frequency transmission lines consisting of metal strip lines and metal plates. Each metal strip line comprises a main input port and N output ports, wherein an annular strip line used for impedance matching is arranged between the main input port and the N output ports; the main input port is connected with the annular strip line by M parallel branch strip lines; the annular strip line is connected with the N output ports by N output branch strip lines; resistors are arranged between at least two of the output branch strip lines; and each resistor is connected with the two output branch strip lines by resistor connecting strip lines; M is greater than or equal to 3 and N is greater than or equal to 1. The power divider has the characteristics of small size and high isolation; the insertion loss of the power divider can be reduced by size reduction; the isolation between array unit channels can be improved by improving the isolation of the output ports of the power divider, so that the influence of mutual coupling between antenna array units is reduced, and the radiation performance is improved; and in addition, the power divider is in a pure plane structure, is easy to process and excellent in engineering practical value.

The invention discloses an early warning method for deterioration of bearing capacity of a railway steel truss arched bridge girder. The method comprises the following steps that 1, temperature data and strain data are collected; 2, components, influenced by train loads, in the strain data are removed; 3, main components of the temperature data and temperature difference data are extracted; 4, a mathematic model between the main components of the strain data and the main components of the temperature data and the temperature difference data is built; 5, the mathematic model is utilized for calculating a residual error between measured strain data and analog strain data; 6, the bearing capacity of the girder is evaluated through the strain residual error. According to the early warning method, the early warning in the deterioration process of the bearing capacity of the railway steel truss arched bridge girder is achieved, and good project practical value is achieved.

The invention discloses a linear engineering rock slope stability semi-quantitative automatic evaluation system. The linear engineering rock slope stability semi-quantitative automatic evaluation system comprises an input module, a sorting module, a drawing module, a judgment module, a storage module, an output module and a display module, wherein the sorting module is connected with the input module, the display module, the drawing module, the judgment module and the storage module respectively; the drawing module and the judgment module are connected with the output module respectively; the display module is connected with the input module, the sorting module, the drawing module and the judgment module respectively. In the system, annotation data and slope list data are sorted automatically, annotation points used in different segments of slopes in the slope list data are screened rapidly and accurately from the annotation data, and drawing work is finished automatically, so that the workload is lowered, the working efficiency is increased, the labor cost is lowered, errors caused by human factors are avoided, and the accuracy is increased; a generated judgment result is accurate, and the system can be directly applied to engineering geological survey reports or design reports.

The invention discloses electromagnetic interference modeling and simulation method and device. The method comprises the following steps: establishing a low-frequency impedance model of a direct-current brush motor; based on the low-frequency impedance model, establishing a low-frequency equivalent circuit model for commutation of the direct-current brush motor, and obtaining the low-frequency characteristics of an interference source by use of the low-frequency equivalent circuit model; calculating the high-frequency characteristics of the interference source by use of the low-frequency characteristics of the interference source; establishing a full-wave model of the simplified structure of the direct-current brush motor; integrating the high-frequency characteristics of the interferencesource into the full-wave model to obtain an integrated model; performing numerical simulation calculation on the integrated model to obtain the electromagnetic interference of the direct-current brush motor. The method and the device disclosed by the invention realize modeling and simulation analysis of the direct-current brush motor in the design stage. Meanwhile, based on the modeling and electromagnetic compatibility principle, the interference source characteristics with high frequency of hundreds of MHz are worked out, thus the method and the device can cover a relatively wide frequencyrange of electromagnetic compatibility and have a relatively great engineering value.

The invention discloses a power transmission line modeling method used for net distance measurement and a distance measurement device thereof. The modeling method comprises the following steps that 1) the distance measurement device is installed below a suspension string, an endpoint O is determined, an auxiliary distance measurement device is installed on a lead to be measured, two endpoints A and B are determined through movement of the auxiliary distance measurement device, and length L1 of a line segment OA, length L2 of a line segment OB, an inclined angle theta1 between the line segment OA and the horizontal plane and an inclined angle theta2 of the line segment OB and the horizontal plane are respectively measured; 2) a rectangular plane coordinate system with the point O acting as the origin of coordinates is established, and the coordinates of point A and the coordinates of point B are substituted into a parabolic model formula y=x2+mx+n of the lead to be measured so that parameters m and n are obtained; and 3) the auxiliary distance measurement device acquires position information of the lead to be measured and forms the position information and the parameters m and n of the parabolic model into a data frame to be wirelessly transmitted to a remote server. According to the method, the modeling process is simplified, the working efficiency is high and the operating risk is low.

The present invention discloses a ground penetrating radar image denoising method based on shearlet conversion. The method comprises the steps of: performing frequency domain Fourier transform of collected ground penetrating radar data, performing frequency domain windowing processing, performing non-subsample shearlet conversion of the ground penetrating radar data after windowing processing, employing a double-variant model based on the maximum posterior probability estimation, performing threshold value shrinkage processing of shearlet coefficients with different sizes in different directions, updating the coefficients, and performing inverse shearlet conversion for the new shearlet coefficients to obtain a ground penetrating radar frequency domain image after denoising. The algorithm implementation is simple, the denoising effect is good, and the ground penetrating radar image denoising method based on shearlet conversion has a good engineering practical value.

The invention discloses a power distribution network fault section positioning method based on a FDM. The method comprises the following steps: firstly developing various measurement point zero-sequence currents after a single phase ground fault is existent in the power distribution network based on a generalized Fourier decomposition method (FDM) so as to obtain a series of orthogonal and mutually-independent Fourier intrinsic band functions (FIBFs) with self-adaptivity; and then defining Fourier-Hilbert spectrum (FHS) based on various band functions, and further constructing transient energydensity functions of various measurement point zero-sequence current after the fault based on the marginal spectrum, and forming fault positioning criterion. Through the positioning method disclosedby the invention, the effective technical support can be provided for the quick and accurate positioning of the single-phase ground fault of the power distribution network, and the positioning methodhas good engineering practical value.

The invention discloses a moving target line spectrum recognition method based on frequency-energy fluctuation characteristics. The method mainly comprises high-resolution low-frequency LOFAR spectrumanalysis, line spectrum trace feature extraction, line spectrum fluctuation degree calculation and moving target line spectrum recognition. The method is based on the line spectrum characteristics ofa moving target; that is to say, the moving target line spectrum has a certain fluctuation near a certain frequency, and the energy of the moving target line spectrum also has a certain fluctuation with time. The line spectrum frequency-energy fluctuation characteristic of the moving target is represented by utilizing the line spectrum fluctuation degree; according to the method, the line spectrum fluctuation degree mean value and variance characteristics are extracted, moving target line spectrum identification can be effectively achieved based on a linear discrimination function, moving target line spectrums can be well distinguished, a good characteristic basis is provided for target detection and classification identification, and concerned moving target line spectrums can be effectively distinguished from a plurality of acquired line spectrums; the method can be used in passive all-direction buoy and subsurface buoy target detection and classification identification, and has goodengineering practical value.

A digital thyristor dual-ring direct current speed regulation device belongs to the field of motor control. The digital thyristor dual-ring direct current speed regulation device comprises a digital thyristor, a control circuit, a digital triggering interface, an amplifying circuit, a digital tachometer circuit, a photoelectric encoder, a direct current motor, a keyboard / display circuit, a synchronous transformer, a synchronous circuit and a rectifying circuit. A gate pole of the thyristor is connected with a port of the amplifying circuit. A control circuit port is connected with a digital tachometer circuit port, a keyboard / display circuit port, a synchronous circuit port and a rectifying circuit port. The digital tachometer circuit port is connected with a direct current motor shaft through the photoelectric encoder. The control circuit comprises a single-chip microcomputer 8051, a programmable timing / counting chip, a programmable I / O (input / output) interface expansion chip and an A / D (analog to digital) converting chip. The digital thyristor dual-ring direct current speed regulation device is high in speed regulation range, low in overshoot of current and rotation speed, short in settling time and dynamic recovery time, stable in starting and high in control precision, and floating speed regulation is achieved.

The invention discloses a power transmission line dynamic capacity increasing method and system. According to the method, the steady-state temperature data / transient temperature rise data of all partsof a wire are measured, a maximum steady-state current-carrying capacity / maximum transient current-carrying capacity are calculated through a neural network model, and the method is more accurate incalculation compared with a conventional method. Meanwhile, a previous round of result is used as training data of a new round of neural network model, the accuracy is further improved along with continuous accumulation of the actual operation data, and the method has good engineering practical value.

The invention discloses a water resource allocation method based on a decomposition coordination idea of a heuristic large system., which comprises the following steps of: performing water resource allocation on each calculation unit period by period by taking a natural river channel topological structure as a basis and taking the number of the calculation units as a cycle; taking the water shortage of each subsystem as heuristic information, considering the maximum supplementable amount of the riverway and the water supply capacity in the calculation unit, and performing compensation scheduling on the ecological flow of the cross section in the riverway after the calculation unit lacking water is processed; and following groundwater supplement configuration, groundwater water extraction capacity constraints and annual groundwater amount control in all time periods need to be considered at the same time, subsystem water shortage and regional groundwater consumption serve as heuristic information, and the groundwater consumption is configured. The water resource allocation method provided by the invention is high in calculation speed and high in calculation efficiency. Through the combination of the simulation model and the actual operation rule, the related constraints of the configuration problem can be better processed, the random optimization strategy is closer to the reality than the random optimization strategy of the heuristic intelligent algorithm, and the engineering practical value is better.

The invention relates to an on-line soft measurement method for furnace-entering gas components of a full-combustion converter gas industrial furnace. The soft measurement method comprises the following steps: acquiring real-time data of operation parameters of a combustion system; Preprocessing the collected data to obtain effective data for solving the calorific value of the gas; According to the obtained effective data, calculating to obtain a coal gas dry basis heat value; According to the method, the coal gas dry basis heat value is obtained through indirect solving according to the relation between the dry air amount and the coal gas heat value, and the volume content percentage of each component of furnace entering and exiting coal gas is further calculated. The method is suitable for burning converter gas and adopts air and combustion equipment adopting a gas double-preheating technology. The calculation result can be used for guiding the combustion optimization adjustment of the combustion equipment, a basis is provided for the safe and economic operation of the combustion equipment, the inconvenience and difficulty brought to the operation of the combustion equipment dueto the fact that the gas composition online analyzer is not configured in most existing steel mill gas combustion systems are solved, and the engineering practical value is very good.

The invention discloses an online measuring method of a metallurgical gas calorific value based on combustion system running parameters. The online measuring method comprises the following steps thatreal-time data of the running parameters of a combustion system is obtained; the collected data are preprocessed to obtain effective data used for calculating the gas calorific value; and a gas dry base calorific value is calculated based on the obtained effective data. According to the method, the gas dry base calorific value is calculated through the relationship between the dry air volume and the gas calorific value. Calculating results can be used for guiding combustion optimization adjustment of combustion equipment to provide reference for safe and economical running of the combustion equipment. Through the online measuring method, inconvenience and difficulty caused by the fact that currently, in most gas combustion systems of steel mills, combustion equipment is not provided with an online gas calorific value analyzing device are removed, and high engineering practical value is achieved.

The invention discloses a steel mill gas sulfur content soft measurement method. The theoretical dry flue gas amount generated by unit volume of gas combustion is directly calculated through the gas heat value, the actual dry flue gas amount generated by unit volume of gas combustion is further obtained by combining with flue gas oxygen content calculation, and finally the sulfur content of the gas is calculated by combining with the SO2 emission concentration in the flue gas. The measuring method is particularly suitable for gas combustion equipment such as a gas boiler. The sulfur content ofthe coal gas can be deduced reversely by means of online monitoring SO2 emission concentration, coal gas heat value configured by combustion equipment, flue gas oxygen content and other online measurement data, and therefore online soft measurement of the sulfur content of the coal gas is achieved. Compared with a traditional measurement method, the calculation precision is not reduced, but the solving process is greatly simplified.

The invention discloses a remedying and reinforcing method for precast hollow driven piles. The method includes the first step of checking, calculating and determining construction parameters of the single-pile allowable bearing capacity P and construction parameters of the foundation settlement S after remediation and reinforcement, the second step of carrying out statistics on defective precast hollow driven piles in a foundation reinforcement range according to a design drawing, then carrying out field measurement and location and making marks, and the third step of installing a drilling machine on a designated position of one precast driven pile, enabling a drill pipe to penetrate through the hollow portion of the precast driven pile and then starting drilling, wherein the drill pipe must keep vertical in the drilling process, the precast driven pile must be reinforced at an expected depth, and the like. Through the method, the bearing capacity and the settlement of the defective precast hollow driven piles can meet requirements of a project, and the construction quality can be easily ensured, so the remedying and reinforcing method for the precast hollow driven piles has good practical value on the project.

The invention provides a gas heat value soft measurement method based on a combustion system operation parameter. The soft measurement method comprises the steps of acquiring real-time data of the combustion system operation parameter; preprocessing the acquired data, and obtaining effective data for solving the gas heat value; and according to the acquired effective value, calculating a gas dry base heat value. According to the method, the gas dry base heat value is indirectly calculated according to a relation between a dry air amount and the gas heat value, and a result can be used for guiding combustion optimization adjustment of combustion equipment, thereby providing a basis for safe and economic operation of the combustion equipment, setting inconvenience and difficulty in combustion equipment operation caused by no gas heat value online analyzer in a majority of steel plant gas combustion systems, and realizing high practical engineering value.

A planar multi-stage power divider comprises multiple radio frequency transmission lines composed of a metal strap line and a metal plate, wherein the metal strap line of each radio frequency transmission line comprises a lumped input port and K layers of ring strap lines surrounding the lumped input port, the connection between each lumped input port and the corresponding innermost-layer ring strap line and the connection between the ring strap lines are achieved through Y connection strap lines, the outermost-layer ring strap line of each radio frequency transmission line is connected with X output ports through X output strap lines extending outwards, and an isolation resistor is connected between every two adjacent output strap liens through a resistor connection strap line, wherein X is larger than or equal to 3, Y is larger than or equal to 5 and K is larger than or equal to 2. A plane of the power divider has multiple ports and is miniaturized, the flexibility of the X output ports is high, the bandwidth of the power divider is obviously increased through arrangement of the K layers of ring strap lines around each lumped input port, the isolation degree between the ports is good, and the power divider is easy to process and obtain and has good engineering practical value.

The invention belongs to the field of unmanned driving path planning, and relates to an unmanned vehicle path planning algorithm based on an improved RRT algorithm. Initializing positions and course angles of a map space, a starting point and a target point, automobile basic parameters, algorithm parameters and obstacle information in the environment; and introducing a target probability sampling strategy to obtain the position of a random sampling point Xrand. And defining a nearest node Xnear by using a multi-information fusion evaluation method. And expanding the random tree by using a target bias expansion mode, and performing smooth connection by using a Bezier curve in a node connection process. And repeating the steps until the random tree is expanded to the connectable range of the target point, and directly connecting the random tree and the target point by using a Reeds-Shepp curve. According to the method, the convergence speed of the algorithm can be effectively improved, the path length is shortened, the path smoothness is improved, the memory occupation is reduced, the kinematics constraint of the intelligent automobile is considered, and the method has good engineering practical value.

The present invention discloses a power distribution network reconstruction method based on fuzzy multi-target cooperative optimization. The method comprises the following steps of establishing a multi-target cooperative optimization model of the power distribution network reconstruction; carrying out the objective function fuzzy processing; transforming a fuzzy multi-target model into a single target model; adopting a tabu algorithm to solve a power distribution network reconstruction model. According to the present invention, a power distribution network reconstruction mathematical model for cooperatively optimizing multiple targets of enabling the network loss and the feeder line load balance index to be minimum and realizing the least switch operation times, is established, a fuzzy membership function is introduced to carry out the fuzzy processing on the targets, and according to the maxi-min rules of the fuzzy set theory, a multi-target optimization problem is transformed into the single target nonlinear planning problem; the tabu algorithm is used to optimize and solve the power distribution network reconstruction model, for a 69-node power distribution network system, four different optimization schemes are compared and analyzed, and the simulation results verify that the provided model and solution method are correct and effective.

The invention relates to an intelligent vehicle automatic driving method based on amendable proportional guidance. The method comprises the following steps: measuring the distance of deviating from alane center line by an intelligent vehicle, and estimating the differential of the deviation distance, assuming that a target is located on the lane center line and moves along the movement of the intelligent vehicle on this basis, computing a visual angle change rate of the assumption by adopting the proportional guidance law, amending on this basis to obtain the visual angle rate based on the amendable proportional guidance, and finally forming the automatic driving rule by adopting the visual angle rate based on the proportional guidance and the amended visual angle rate, thereby realizingthe automatic driving of the vehicle along the lane line. Through the method disclosed by the invention, the vehicle location deviation and the angle conversion problem of a front wheel steering anglecan be well solved through smart design, the experiment shows that the intelligent vehicle automatic guidance method is fast in elimination speed on the aspect of eliminating the location deviation,and is smooth in dynamic response, free from obvious fluctuation and oscillation conditions, extremely comfortable in riding quality and can be extensively applied to various unmanned vehicles.

The invention relates to an aircraft lateral parallel centroid control method based on overload control. Lateral acceleration, speed and position signals of the aircraft are measured by installing a KY-INS300 optical fiber integrated navigation system. On one hand, an overload signal is obtained by converting an acceleration signal, then nonlinear lag correction and proportional integral are carried out, and an overload comprehensive signal based on a lateral overload error rather than a lateral overload error is obtained and directly transmitted to a yawing rudder system. On the other hand, alateral position error signal is obtained by comparing the lateral position signal with an expected position instruction signal, and then nonlinear advanced correction and nonlinear integration are carried out to obtain a position error comprehensive signal which is directly transmitted to an aircraft yaw rudder system. Through the overload and position error parallel control method, the lateralcentroid control of the aircraft has good rapidity and good damping characteristics due to the introduction of overload signals, and has the advantages of simple scheme and simple measurement.

Embodiments of the invention disclose a capacitive sensor-based liquid level measurement device. The device comprises a capacitive sensor and a capacitance measurement instrument which is connected with the capacitive sensor, wherein the capacitive sensor is used for sensing the liquid level of to-be-tested liquid and converting the liquid level information into a capacitance value; and the capacitance measurement instrument is used for detecting the capacitance value and calculating the liquid level of the to-be-tested liquid according to the capacitance value. The device is suitable high-temperature (300 DEG C) liquid; the measurement precision is high; the non-invasion type capacitive sensor is adopted so that the service life of the measurement device is greatly prolonged; connection mechanisms such as a connection rod and the like are not used so that the volume of the measurement device is greatly decreased; and the structure is simple and the leads are few, so that the reliability of the device is improved, and the device is particularly suitable for small nuclear heating reactors and has a favorable application prospect.

The invention discloses a liquid level measuring device based on a capacitive sensor. The liquid level measuring device comprises a capacitance detection unit, an initialization unit and a control chip unit, wherein a plurality of capacitive sensors used for detecting a liquid level in a storage tank are arranged in the storage tank, and liquid level capacitive sensors used for carrying out real-time capacitance data detection on liquid level detection points are arranged at different vertical heights; the initialization unit is used for initializing a capacitance during no-load and a capacitance value during full-load; the control chip unit is used for making the plurality of capacitive sensors periodically measure capacitance data of an environment in the tank so as to obtain a state ofa current fixed point liquid level and judge whether a liquid reaches a liquid level height at the fixed point; and meanwhile, the capacitive sensor for detecting a gas is arranged at a top of the tank, a change curve of the capacitance in the gas along with a change of the liquid level of a liquefied natural gas in the sensor is counted, and the height of the current liquid level is calculated inan auxiliary mode through the capacitance value measured by the capacitive sensor for detecting the gas. The structure is simple, the number of leads is small, and device reliability is improved.

The invention discloses a rock mass critical sliding surface limit analysis method which comprises the following steps: collecting distribution ranges of rock masses with different properties, structural surfaces and soft layers in a target area through geological investigation; measuring physical and mechanical parameters of rock masses, structural surfaces and soft layers with different properties; dividing units; by taking the stress components of all nodes as independent variables, constructing a unit static balance constraint equation, a node stress known boundary condition constraint equation, a node stress yield criterion constraint equation and a target function, and forming a mathematical model for rock mass critical sliding surface limit analysis; and solving the optimal solution of the mathematical model and the node where the tight constraint of the mathematical model is located through a computer program, and determining the critical sliding surface of the rock mass. The method has the advantages that the method for quantitatively determining the critical sliding surface of the rock mass is provided, the defect that whether the rock mass is stable or not can only be qualitatively judged in the prior art is overcome, the theoretical basis is strict, the applicability is high, the calculation conclusion better conforms to engineering practice, and the method has good engineering practical value.

The invention relates to a metallurgical gas calorific value soft measuring method based on a heat exchange parameter of a gas preheating system. The soft measuring method is characterized in that based on real-time data of operating parameters of a combustion system, a gas calorific value is obtained through indirect solving through calculation, the idea roughly comprises the steps that an initial gas calorific value is firstly assumed, an actual dry flue gas quantity calculation value and an actual dry flue gas quantity check value are solved according to the assumed gas calorific value, theassumed gas calorific value is repeatedly corrected according to the ratio of the actual dry flue gas quantity calculation value to the actual dry flue gas quantity check value, and finally the accurate gas calorific value is obtained. The method can be used for guiding combustion optimization adjustment of pure-burning blast furnace gas or the pure-burning converter gas equipment, and a basis isprovided for safe and economic operation of combustion equipment, so that the problem that gas calorific value online analyzers are not arranged on the combustion equipment in most steel plants, andconsequently inconvenience and difficulties are brought to equipment operation is solved, and the good engineering practical value is achieved.