Abstract:Since the original situation information in the unmanned swarm confrontation problem is complicated, it is difficult to accurately identify the situation elements such as the swarm formation and swarm movement trend. In order to improve the identification ability for unmanned swarm situation elements, an identification method for unmanned swarm adversarial situation elements using Transformer was designed. On the basis of the Transformer model, a Transformer-Decoder attention layer model that can be applied to unmanned swarm confrontation situation element identification problem was constructed, so as to achieve a good ability to identify swarm situation elements. The inter-layer attention structure was designed to improve the feature expression ability of Transformer-Decoder to further improve the recognition accuracy. First, the situation sequence information of the unmanned swarm was input into LSTM and encoded into time sequence feature information. Then the Transformer-Decoder attention module and the inter-layer attention module were used to extract the comprehensive high-order situation information of the swarm. Finally multi-dimensional classification network and softmax layer were adopted to realize the classification of multiple situation elements. The experimental results showed that the unmanned swarm adversarial situation elements recognition method using Transformer and inter-layer attention exhibited good performance on situation element classification problem, and could accurately classify multiple situation elements synchronously. Compared with the baseline method, the swarm situation recognition method using Transformer and inter-layer attention had higher accuracy in the recognition of swarm formation and movement trend. Especially in the classification of situation elements that reflect the relative trends within the swarm, the proposed method clearly showed better performance.

Abstract:To reduce the computational cost and improve the computational efficiency in optimal design of seismic isolation device for ultra-high voltage (UHV) porcelain-housed surge arresters, this paper proposes a novel modeling method for lower degrees of freedom for arresters. The characteristic of the elasticity at the cementing joint between porcelain housing and metallic flange was firstly investigated quantitatively based on test data. It shows that the flexural rigidity distributed unevenly along the axial direction of the arrester, which provides basis for the discretization of elasticity characteristics and the establishment of the multibody model of the arrester. Then, each porcelain unit was taken as a rigid body, and the flexural behavior of the overall system was simulated by torsional springs at flange cementing joint. A model of multibody system with pin-joints and torsional springs was constructed based on the multibody dynamics theory. The joint coordinate method was adopted to derive the governing equations of motion for the multibody system under seismic excitation. Lastly, a 1 000 kV porcelain arrester was modeled by the proposed method, and static analysis and seismic response history analysis were performed. Comparison between calculated results and test results showed a good agreement. Results show that the numbers of degrees of freedom of the multibody system for an arrester was equal to the numbers of its porcelain units, which is usually less than 6. Due to its simplicity in form, it is easy to construct the model of isolated arresters equipped with seismic isolation device by the proposed method. The method can also be easily extended to the seismic analysis of similar column-type porcelain electrical equipment in substation.

Abstract:To improve the measurement accuracy of interferometric imaging spectrometer for space target, reduce the response difference of each detection element in the sensor, and improve the on-orbit radiance measurement accuracy of imaging spectrometer, we proposed a spatial calibration method based on calibration field reflectance measurement parameters, calculation program simulation, and on-orbit measurement data comparison of imager. Firstly, the concept of hyperspectral calibration was introduced, and a high-precision calculation method of pupil entrance radiance under different spectral response functions and different site conditions was proposed. Secondly, the on-orbit relative radiation correction of the interferometric imaging spectrometer was performed, so as to correct the correspondence difference of each detection element in the sensor. The on-orbit absolute radiometric calibration test was carried out by using reflectance-based method. The on-orbit radiometric calibration calculation model was established for visible and near-infrared bands. The optimization design problems of test scheme including multiple reflectivity sites and high-precision test area indication were solved, which realized high-precision on-orbit calibration of spaceborne high-resolution interferometric imaging spectrometer. Results show that the on-orbit measurement accuracy of imaging spectrometer reached 5% by using this calibration technology. The environmental conditions of the calibration sites had impacts on the calculation accuracy of the model: the reflectance-based method was suitable for large-area uniform field, while the small-area uniform field could be calculated by introducing the adjacent pixel effect. The accuracy of reflectance measurement data could be improved by arranging manual indication targets. The calibration technology has been applied in engineering.

Abstract:In view of the conceptual design optimization problem of solid rocket motor (SRM) that takes the optimal range of aircraft as the objective, the geometric parametric models of grain, combustion chamber, and nozzle of complex three-dimensional motor as well as the performance models of thrust and mass were firstly established under fixed-scale constraints. Meanwhile, considering the harsh flight environment and high performance requirements of boost-glide aircraft, a multi-constraint range capability evaluation model was proposed. Then, the maximum range of aircraft corresponding to the current motor scheme was evaluated by adaptive Legendre-Gauss-Radau pseudo-spectral method, and a constrained mixed-integer parameter optimization problem was constructed. In order to solve the high time-consuming of the mixed-integer parameter optimization problem, the Kriging surrogate model was introduced, and the sequential approximate optimization algorithm for real number was adjusted by adding integer constraints. For slow convergence rate of the traditional global sampling criterion, a local enhancement strategy was proposed and verified numerically. Simulation results show that the flight trajectory obtained by the improved adaptive pseudo-spectral method satisfied all the constraints, and the optimized maximum range was increased by 12.89% compared with the original SRM scheme. The solution of the proposed algorithm was consistent with that of genetic algorithm, but the number of time-consuming function calls was only 2% of the genetic algorithm. Compared with the traditional sequential approximate optimization algorithm, the proposed algorithm had global search capability, and effectively improved the convergence rate.

Abstract:To reduce the demand for telemetry, tracking, and command (TT&C) resources in the on-orbit software update process and shorten the update upload time, this paper proposes a statement-level software update method that requires no operating system support, has a small amount of upload data, and can be flexibly controlled. Firstly, precompiled command was used to optimize the program space to make the code of different modules stored in different segments after the compilation, so as to reduce the impact of code modification on the loaded file. Secondly, the matching path between the reference segment and the update segment was solved segment-by-segment, and the difference content of each segment was extracted, which could greatly reduce the size of the differential patch. Thirdly, through the design of version guidance program, the flexible control of satellite software version was realized. Finally, the reliability design of the files and the program was performed, which could ensure safety of the entire update process. The method was fully tested on the ZDPS-3A satellite platform. Results show that the update method proposed in this paper could be applied to on-board computers without operating systems. The software state could be rolled back and the update process was reliable. Besides, compared with the traditional method of extracting different content, the average reduction of patch file size generated by this method was more than 50.00%, greatly shortened the update upload time. Therefore, the proposed method can meet the demand for low volume data update of on-board software and can be applied to other spacecrafts such as micro-satellites.

Abstract:To reduce the low-frequency fluctuation and radiated noise of pump-jet propulsor (PJP), by adjusting the pre-whirl angles including inlet angle, outlet angle, and stagger angle of a given PJP, this paper numerically analyzes the hydrodynamic performances of the PJP with limited range of stator pre-whirl angles. Results showed that the thrust, torque, and peak efficiency all increased with increasing pre-whirl angle, and the stagger angle had the greatest effect, followed by the outlet angle, and the inlet angle was the least. Through analysis of the rotor force fluctuation in frequency domain, it was found that the force fluctuation of single rotor was affected by stator, and the corresponding frequency was stator blade passing frequency (BPF_s), with the maximum amplitude at 1BPF_s, while the frequency corresponding to the total thrust was jointly affected by rotor and stator, with the maximum at 4BPF_r. The standard deviation of surface pressure on blades was analyzed, and the region with the highest fluctuation was near the leading edge and tip of rotor, while that for stator located around trailing edge. Further analysis on pressure fluctuation characteristics of probes around rotor and stator was carried out. The obtained major frequency was 1BPF_r, and the most intense pressure fluctuation was observable at medium and high radius of PJP's wake. Overall, the low-frequency pressure fluctuation of PJP was increasing with the increase in pre-whirl angle, yet the influence law of three methods of adjusting pre-whirl angles was different under positive and negative angles. In addition, the phases of probes at same axial position but different radial positions near the leading edge of rotor were studied. Results showed that the effect of outlet angle and stagger angle was more significant, and the phase difference was obviously different according to the sign of pre-whirl angles.

Abstract:To construct a human-machine interaction (HMI) information structure model of manned submersible under complex tasks and improve the understanding of submersible cockpit designers on the cognitive process of oceanauts for mission information, this paper proposes a construction method of all elements hierarchical structure model with impact factors based on decision ladder (DL) and DEMATEL-ISM method. Taking a near-bottom operation of a manned submersible as the object, DL was used to analyze the task information demand and processing process of the oceanaut, and identify the elements and relations of HMI information. The comprehensive impact matrix and attribute eigenvalues were calculated based on DEMATEL. Combined with the research purpose, the threshold calculation method of the overall impact matrix and the discriminant formula of the reachability matrix were improved to obtain the reachability matrix containing impact factors. Then, a stable cause-effect hierarchy structure was extracted by the method of anti-rotation hierarchy extraction, and a fuzzy operator pair was introduced to calculate the skeleton matrix with influence value. The HMI information structure model containing influence value was constructed by combining the hierarchical structure. Results show that a six-layer directed weighted structure model consisting of 31 interactive information elements and their relations was obtained, and the effectiveness of the proposed method in ensuring node integrity, optimizing the hierarchical structure, and quantifying factor relations was proved through scheme comparison. The obtained model defines the attribute characteristics, causative relationship, and causative degree of HMI information elements, which has good explanatory power for the HMI information processing process based on the cognition of the oceanaut under complex tasks and can provide theoretical basis for the design of HMI information of manned submersible cabin.

Abstract:Considering the problems of numerical divergence and initial value dependence of the output error method in parameter identification of unstable aircraft, a system identification method combining neural network, particle swarm optimization algorithm, and Levenberg-Marquardt (LM) algorithm was designed. First, in order to solve the numerical divergence problem of the output error method, the neural network was utilized to approximate the dynamic characteristics of the system to be identified. The flight test data at different moments were used to train the neural network. The trained network could directly predict the motion state at the next moment, so as to avoid solving the unstable motion equation. Then, the particle swarm optimization algorithm was adopted to search the best damping factor in LM algorithm, and the improved LM algorithm was used to replace the Gauss-Newton algorithm in the output error method. Next, the improved LM algorithm was combined with the trained neural network to form a new parameter identification algorithm. Finally, the proposed algorithm was verified based on the closed-loop simulation flight test data of unstable aircraft. Research results show that compared with the estimation results of the traditional least square method and output error method with artificial stabilization, the proposed algorithm had higher estimation accuracy, and it could randomly select the initial value of the parameters to be identified, which overcomes the dependence of the output error method on the initial value of the parameters. The research results of this paper can be directly used in the identification of other unstable nonlinear dynamic systems, as well as other nonlinear optimization fields after modification.

Abstract:Since the satellite maneuvers directly affect the performance of positioning, navigation, and timing service of the global navigation satellite system, when satellite maneuver occurs, the maneuvering satellite needs to be processed separately so as to generate high-precision orbital information. The carrier phase triple difference method can be used for satellite maneuver detection, but it is affected by differential measurement noise. Although such noise can be reduced by multi-epoch accumulation, the results of maneuver detection may be affected by the selection of baseline. Therefore, a satellite maneuver rapid detection and period determination method based on discrete wavelet transform was proposed. On the basis of the carrier phase triple difference model, the carrier phase triple difference residuals were extracted, and the priori information of the triple difference residuals at the start and end moments of satellite maneuvers was exploited. The carrier phase triple difference residuals were then decomposed based on the scale characteristics of multi-resolution analysis. The level of wavelet decomposition was determined by the detection results of detail and approximation coefficients. By analyzing the approximation coefficients and detail coefficients of different frequency characteristics, the satellite maneuver information implicit in the carrier phase triple difference residuals was obtained, and the satellite maneuver rapid detection and period determination could be realized. Experimental results show that compared with the traditional carrier phase triple difference method, the discrete wavelet transform method achieved faster detection of satellite maneuvers by using the single-epoch method, and the results of satellite maneuvering detected by different baselines were consistent, which is a more accurate satellite maneuver detection and period determination method.

Abstract:To reduce the event-triggered times of uncertain discrete-time linear/nonlinear systems and save communication resources, we proposed an event-triggered control (ETC) strategy based on state approximation. First, the approximate solution of the uncertain discrete-time linear system was constructed piece-wisely by using the analytical solution of the certain linear system, sampled signals, and system matrices. The measurement error was defined as the difference between the current system state and the approximate solution. The event-triggered condition and controller were constructed, and the stability conditions were established by designing Lyapunov functions. Then, for a class of Lipschitz discrete-time nonlinear system, linearization was performed. According to the analytical solution of undisturbed linear system, similar to the technique for linear system, the piece-wise approximate solution was constructed, and the measurement error was redefined. The event-triggered condition and controller were designed respectively, and the stability conditions of the system were developed. By combining the state approximation technique with dynamic triggered method, the measuring error and the trigger threshold were reduced, and the event-triggered times were further decreased, indicating better control effects. Simulation results of inverted pendulum system and Chua's circuit showed that compared with the traditional event-triggered scheme, the state approximation approach significantly reduced the event-triggered times and avoided wasting communication resources.

Abstract:To improve the heat rejection efficiency of low Earth orbit (LEO) communication satellite and reduce the platform mass, through the analysis of the orbital heating flux of each honeycomb panel of in-orbit satellite, this paper proposes an inverted trapezoidal extension panel with heat pipes as conduction network. First, according to the integral average values of orbital heating flux of LEO communication satellite in orbit, the average heat rejection capacity of each honeycomb panel was obtained through numerical calculation, and the heat rejection performance of two box-type configuration schemes was compared. Then, in order to ensure the uniform temperature of honeycomb panels, a heat pipe network consisting of embedded heat pipes and external heat pipes was designed, so as to enhance the thermal coupling characteristics within and between honeycomb panels. Finally, the inverted trapezoidal extension panel configuration scheme was adopted for a LEO communication satellite, and hot and cold thermal balance tests were carried out. Research results showed that with the same area constraint, by using the inverted trapezoidal extension panel configuration, the heat rejection capacity of +X honeycomb panel was improved by 36.3%, -X honeycomb panel by 36.4%, +Z honeycomb panel by 10.2%, -Z honeycomb panel by 98.6%, and the heat rejection capacity of the whole satellite was improved by 34.6%, compared with the positive trapezoidal configuration. The thermal balance test results showed that the satellite platform met all temperature requirements under hot and cold cases. The whole satellite met the heat rejection requirement of 2 200 W, and the peak heat rejection was 870 W for the +Z panel phased array, indicating the feasibility of the inverted trapezoidal extension panel configuration based on the heat pipe network.

Abstract:A testability test optimization method based on subsystem contribution rate and prior distribution credibility was proposed to deal with the problems such as the difficulty in obtaining system-level prior information, the unreasonable calculation of prior distribution weight, and the large sample size in existing methods. First, the testability multi-source prior information was systematically analyzed and the subsystem contribution rate was defined. On this basis, the subsystem prior data was converted to obtain the system-level prior data by the information theory. Then, the similarity measure of prior distribution was introduced to characterize the compatibility between prior distribution and experimental data. Next, the technique for order preference by similarity to ideal solution-analytic hierarchy process (TOPSIS-AHP) method was proposed to determine the credibility of prior distribution, and then the mixed prior distribution was obtained. Finally, on the basis of the mixed prior distribution determined by subsystem prior information, the sequential posterior odd test (SPOT) method was used to make the test optimization plan. Case analysis results show that the mixed prior distribution obtained from the data conversion method based on contribution rate and the weight calculation method based on credibility was more accurate. The sample size of the SPOT method decreased by 18.6% on average compared with the sequential probability ratio test (SPRT) method, and was 61.1% smaller than the Bayes method. Besides, this method could effectively reduce the risk of both sides. The SPOT method considering contribution rate and credibility has good application effects in acquisition of prior information, weight of prior distribution, number of test samples, and risk of both sides.

Abstract:A method was proposed to realize SiC-SiC bonding at the temperature below 300 ℃. Cu and Au were taken as intermediate layer, and Pt was used to catalyze formic acid atmosphere to pretreat metal surface and provide reducing protective atmosphere for bonding. Firstly, the bonding of SiC samples with Cu layer in N₂ atmosphere, formic acid atmosphere, and Pt catalyzed formic acid atmosphere was studied. By comparing the bonding strength, the possibility of SiC-SiC bonding with Cu interlayer in Pt catalyzed formic acid atmosphere was verified. Secondly, the samples were characterized by scanning acoustic microscope (SAM) and scanning electron microscope (SEM). The influence of key process parameters on the bonding strength was studied by changing the bonding temperature and pressure. Finally, the SiC-SiC bonding results of Cu and Au in different atmospheres were compared. Results show that compared with N₂ atmosphere and formic acid atmosphere without Pt catalysis, Pt catalyzed formic acid atmosphere reduced the oxides on the surface of Cu effectively and realized SiC-SiC bonding with Cu interlayer at low temperature. SAM and SEM images show that there was no obvious void in the bonding interface. Compared with SiC samples with Au interlayer, the bonding strength of SiC samples with Cu interlayer was significantly higher at low temperature, which indicates the superiority of the proposed method in the metal surfaces with oxidation layer. High-strength SiC-SiC bonding at low temperature was achieved through Pt catalyzed formic acid atmosphere pretreatment and protection. Shear strength of 12.5 MPa at 200 ℃ was obtained, and an effective bonding between SiC and SiC was achieved.

Abstract:For the safe operation of buried gas pipeline under the action of landslide debris flow, a pipe-soil deformation analysis model was established based on the thermo-elastic-plastic theory and the pipe-soil coupling method. The axial strain distribution of buried gas pipeline was simulated and analyzed. On the basis of the strain distribution characteristics of buried natural gas pipeline, the prediction model of axial strain distribution of pipeline was determined by nonlinear fitting method. Results show that the soil deformation area under the action of landslide debris flow was mainly the area of debris flow and its vicinity, and the soil deformation in the front area of landslide debris flow was significantly greater than that in the rear area. The main deformation of the pipeline was bending, the deformation between the pipe and the soil was not synchronous, and the deformation of the soil was obviously greater than that of the pipeline. In each path, the pipeline was under both tensile strain and compressive strain. In the area of landslide debris flow action, the extreme values of axial tensile strain were obtained from the bottom and top paths of the pipeline respectively. The breadth and thickness of the debris flow had limited influence on the strain distribution range of the pipeline, and the strain distribution range significantly expanded with the increase in the length of the debris flow, in which the area affected by the debris flow was about 3 times the length of the debris flow action zone. The strain distribution prediction model was related to three parameters of μ, σ, a₁. The data of axial tension and compressive strain of only three positions were needed to determine the axial tension and compression strain distribution of the pipe segment in the region. The research results will provide important theoretical basis for the determination of pipeline strain distribution under pipeline landslide disaster.

Abstract:The influence of the changes in surface albedo on the thermal environment of the mining area due to the destruction of the original vegetation caused by the high-intensity mining of mineral resources was analyzed. Taking Malanzhuang Iron Mine in Qian'an city of Hebei province as an example, the statistical model method was adopted to retrieve the surface albedo based on the visible light band of Landsat remote sensing image, and the pixel trisection model was used to retrieve the vegetation fractional coverage based on NDVI-DFI. By means of radiative transfer equation method, the land surface temperature (LST) was retrieved based on the thermal infrared band of Landsat remote sensing image. With the aid of superposition analysis method, correlation analysis method, and regression analysis method, the response of spatiotemporal heterogeneity of surface thermal environment to the changes in photosynthetic vegetation coverage (f_PV) and surface albedo was quantitatively and visually explored. Results showed that the spatial distribution of surface thermal environment in the study area showed obvious heterogeneity and regularity. The high temperature zone was mainly distributed in the northern Shaheshan stope, central Liuheyu dump, and the unreclaimed Baimashan dump in the south. The moderate temperature zone was mainly located at the edge of the high temperature zone and other bare surfaces. The low temperature zone was mainly located in the northern reclaimed tailings pond and reclaimed waste dump, as well as the green land and water bodies in the area. The spatiotemporal variation of photosynthetic vegetation coverage and surface albedo resulted in a large heterogeneity of the surface thermal environment during the summer midday in the study area. The mean surface temperature of underlying surface in the third phase of the image was ranked as follows: mining area bare rock > dump slag > reclamation vegetation > water body. The regression analysis results showed that f_PV at 0.01 level (double sides) had a negative linear correlation with LST (p < 0.01), indicating that the increase in f_PV has a cooling effect on surface thermal environment, and the determination coefficients (R²)were 0.63, 0.55, and 0.65, respectively. According to the regression coefficient, in 2000, 2008, and 2018, for every 10% increase in f_PV, LST decreased by 0.66, 0.74, and 1.09 ℃. The regression analysis results showed that albedo at 0.01 level (double sides) had a positive linear correlation with LST (p < 0.01), indicating that the increase in albedo has a warming effect on surface thermal environment, and the determination coefficients (R²)were 0.35, 0.40, and 0.48, respectively. According to the regression coefficient, in 2000, 2008, and 2018, every 10% increase in albedo led to the increase in LST by 1.09, 1.36, and 1.76 ℃. The research results will provide a quantitative reference for the evaluation and optimization of the surface thermal environment heterogeneity in mining area.

Abstract:To study the thermodynamic performance limit of two-heat-source combined cycle, an ideal thermodynamic model of two thermal medium heat-work conversion system was constructed. The concept of exergy-driven thermodynamic process (EDTP) was proposed and classified by analyzing the process power relationship between the heat engine region and the heat pump region. Quantitative analysis was performed through the proportion of output power. The parallel flow and counter flow EDTP functions were constructed and solved. The thermal characteristics and thermodynamic performance limits of different types of EDTP under ideal conditions were analyzed. Results showed that the maximum process work of the parallel flow EDTP was greater than that of the counter flow EDTP, and the temperature crossover trend between the exothermic medium and the endothermic medium of the parallel flow EDTP was more obvious. The equivalent temperature rise in the endothermic medium could be used to determine the type of EDTP, and its maximum value could characterize the limit of output power. The evaluation of actual system showed that the total heat exchange of the series-type cogeneration system was 1.97 times that of the basic organic Rankine cycle (ORC), which is more suitable for occasions with simultaneous thermoelectric demand. However, the net output power efficiency (6.55%), exergy efficiency (26.61%), and thermodynamic perfectibility (36.38%) were significantly lower compared with the basic ORC. The method to improve the thermal performance of the two-heat-source combined cycle is worthy of study. This research can provide theoretical guidance for the thermodynamic performance limit and evaluation of different types of two thermal medium heat-work conversion systems.

Abstract:To grasp the fusion combustion characteristics of multiple pool fires adjacent to each other in a shaft with side slits, we carried out tests on the fusion flames formed by two, three, and four pool fires in a 2 m-high test shaft. The influence of the spacing between the pools and the width of the side slits of the vertical shaft with typical arrangements of multiple pool fires was analyzed, and the results were compared with free combustion test results of the same multiple pool fires without the constraints of the shaft structure. Results show that the unique jet air flow formed by the shaft with side slits changed the flame fusion form between multiple pool fires and the thermal feedback to the fuel surface. The fusion rotating flame formed in the shaft strengthened the combustion efficiency and raised the flame height. With fixed structure of shaft, relative strong fusion rotating flame was formed by adopting a pool placement form that enables the fuel surface of each pool to receive the heat feedback of the fusion flame uniformly, and the generating capacity of the fusion rotating flame was strengthened by increasing the number of pools. The parameters of the fusion rotating flame were affected by the coupling of the number and relative position of the fuel pools and the width of the slits on the side of the shaft. With proper slit width on the side of the shaft and the placement method that allows the fuel surface of each pool to evenly receive the heat feedback of the fusion flame, the combustion efficiency was increased by nearly 3.7 times and the peak flame height by more than 30%. In addition, on the basis of the idea of buoyant pool flame superposition circulation, the theoretical models of the burning rate and flame height of the typical multi-pool fusion flame in the shaft were derived and fitted.

Abstract:Due to the high-energy consumption of chilled water system in the central air-conditioning and the difficulty in dynamic adjustment for system equipment parameters with load changes, an adaptive parallel artificial immune algorithm combined with exhaustive method (EM-APAIA) was proposed to optimize equipment operating parameters under different loads, so as to reduce the operation energy consumption of chilled water system. First, the power consumption model of each piece of equipment in the system was established, and the minimum power consumption of all the equipment was taken as the optimal control objective of the chilled water system. Then, EM-APAIA was used to optimize the operation parameters of the chilled water supply temperature, the number of chilled water pumps, and the speed ratio. In the algorithm, the initialization method, migration operator, and mutation probability were improved, and the exhaustive method mechanism was introduced, enhancing its ability to optimize the equipment operating parameters for the chilled water system. Finally, a simulation experiment was carried out on an actual chilled water system of central air-conditioning. Results show that compared with the conventional setting, the total energy consumption of the system was reduced by 14.8% after its equipment operating parameters were optimized by EM-APAIA. The algorithm not only achieved better control strategy than the comparison algorithms, but also exhibited fast convergence speed and strong stability, which can be better applied to the control optimization of the equipment in central air-conditioning chilled water system.