34 results about "Risk theory" patented technology

The invention relates to a safety level evaluation method a power grid, comprising the following steps of: firstly determining a supposed accident list, and sequentially disconnecting elements of the supposed accident list; after a certain element is disconnected, carrying out topological structure analysis and load flow calculation on a system, and then calculating a power grid loss load risk evaluation index, a power grid overload risk evaluation index, a power grid low voltage risk evaluation index and a power grid voltage collapse risk evaluation index; repeating the process till all the elements of the supposed accident list are completely calculated; and then calculating a system single-risk evaluation index and a system total-risk evaluation index. The invention introduces a risk theory and a utility theory to the safety evaluation of the power grid, separately diagnoses the safety of the system from different side surfaces, further obtains the risk evaluation index of the whole system by an analytic hierarchy process (AHP), obtains simple and clear results and has better discrimination and can reflect the occurrence possibility of different accidental accidents and severity degree of a consequence caused by the accidental accidents.

The invention relates to an assessment method for vulnerability of a smart distribution network based on a dynamic probability trend. The assessment method comprises the following steps: adopting a basic function and a random function to form probability distribution for node injection power of the smart distribution network; computing probability distribution for busbar voltage and line power according to Gram-Charlier stage number and semi invariant; utilizing a piecewise function to compute harm severity index caused by voltage, current and power on the smart distribution network; and then computing to output the vulnerability index of the smart distribution network. According to the invention, the method based on risk theory adopts the dynamic probability trend method to access the vulnerability, and enables a self-healing control scheme of the smart distribution network to adapt to change of load and operating environment of the smart distribution network, so that the smart distribution network can operate safely, reliably and economically.

The invention discloses a power grid differentiation-based core backbone network architecture construction method. The importance of lines and nodes in a power system are taken into comprehensive account, the knowledge of a risk theory is referenced, the importance of the lines is obtained by calculating risk indicators of the lines, and the importance of the nodes is evaluated based on the knowledge of a graph theory; and a core backbone network architecture searching model is constructed based on the importance of the lines and the nodes, and network architectures are searched by a particle swarm algorithm to obtain the lines and the nodes for constructing a core backbone network architecture. The importance of the lines is evaluated by line returning risks, so that the importance of the lines can be better reflected from the point of electrical quantity variation; and a fuzzy-membership-based line returning risk evaluation method more consistent with actual conditions is provided, and the influence of uncertain factors of the power system is taken into comprehensive account.

The invention relates to an engineering-risk wireless-sensing early-warning visualization system and method. The system comprises a sensor module, a microprocessor module, a wireless receiving and transmitting module, a site early-warning module, a data storage module, a long-distance early-warning module and an upper computer. The sensor module is arranged in an engineering structure and is connected with the microprocessor module. The microprocessor module is connected with the wireless receiving and transmitting module and the upper computer respectively. The wireless receiving and transmitting module is connected with the site early-warning module, the data storage module and the long-distance early-warning module respectively. The site early-warning module is arranged at an engineering site, the long-distance early-warning module is arranged in a long-distance monitoring room, and the data storage module is connected with the upper computer. Compared with the prior art, the engineering-risk wireless-sensing early-warning visualization system and method are used for safety monitoring and early-warning of the civil engineering, a monitoring theory, an engineering risk theory and an automatic control theory are combined, the limitation of an existing monitoring and early-warning method is broken through, real-time feedback and timely early warning are achieved, and safety in the engineering construction and operation process is guaranteed to the maximum degree.

The invention provides an information security risk assessment method oriented to a typical metallurgy process control system and belongs to the technical field of industrial control system information security. The system robustness under different attack modes and policies is analyzed by establishing an attack model under the typical scenes of the metallurgy process, and therefore, the security risk assessment on the typical metallurgy process control system in different attack modes and a failure mode can be realized. Based on the risk theory, the method is used for performing the security risk assessment by use of a random probability algorithm by defining the metallurgy process control system as a physical information fusion system; from the two aspects of the occurrence probability and the influence of attack sources or failure sources, a security assessment method based on risk indexes is developed. Quantitative estimation is performed based on risk indexes; a security incident set is created based on the established physical information fusion model and attack model, and then the security incident set is combined with the calculated robustness assessment indexes for the quantitative estimation, and therefore, the weak security links in the control system can be located conveniently.

The invention discloses an identification method of vulnerable nodes of a distribution network. The method includes the following steps: (1) establishing vulnerability evaluation indexes based on complex network theory, and a risk evaluation index based on risk theory; (2) using a hierarchical analysis method to carry out weighted summation on the vulnerability evaluation indexes of the distribution network and comprehensively analyze the vulnerability indexes and the risk index, and establishing a comprehensive estimation index of node vulnerability of the distribution network; (3) acquiringstructure data of the distribution network and a power flow calculation result, and calculating the comprehensive estimation index of the distribution network; and (4) outputting the relatively vulnerable nodes of the distribution network. The comprehensive estimation index has the following advantages that: the complex network theory and the risk theory are adopted, a structure of the distribution network is taken into account, fault risks are taken into account, and the identification problem of the vulnerable nodes in the distribution network is comprehensively solved.

The invention discloses an electric power system protection and control method based on a risk assessment. The method comprises the following steps: carrying out the risk assessment on an electric power system, and calculating power network risk values; establishing a protection and control object function; inputting electric power system running states and parameters; and according to the protection and control object function and the power network risk values, formulating electric power system protection and control measures. According to the invention, risk theories are applied to the protection and control of the electric power system, the problem of formulating protection and control measured by reliance on experience of dispatchers is solved, and quantifiable measures can be obtained by use of the method so as to effectively realize safety protection and control of the electric power system. Besides, the method, on the basis of the risk assessment, takes control cost into consideration in an integrated approach, draws up the protection and control object function and formulates the quantifiable protection and control measures according to the object function so as to reduce the control cost as much as possible under the condition that safety protection of the electric power network is realized.

The invention discloses a power grid operating state assessment method based on the risk theory. The method comprises the following steps: data is collated, and a data processing module is established; the outage probability of power grid elements is calculated; the element outage probability data is stored; the power grid operating state is extracted through the Monte Carlo method; the system state is analyzed; system state analysis is performed through a submodule 5 to judge whether problems, such as the circuit overload problem, the voltage out-of-limit problem, the bus isolation problem, the problem that a system is separated into isolated islands, etc., occur; the power grid operating risk indicators are calculated; and the power grid operating state risk indicator result is analyzed to give out the weak link of the power grid. According to the invention, risk assessment is performed on the power grid operating state; the actual operating state of the power grid is simulated by using the Monte Carlo method, the event random nature of the power grid is taken into account reasonably; different risk indicators are used, multi-angle and multi-level assessment is performed on the power grid operating state risk; and the power grid operating state risk assessment result is analyzed to give out the weak link of the power grid.

The invention provides a foundation pit risk management method based on big data analysis and a foundation pit risk management system based on big data analysis. The foundation pit risk management method comprises following steps: step1, establishment of a foundation pit risk management system hardware platform; step2, acquisition of foundation pit risk related information; step 3, dynamic acquisition of foundation pit deformation data; step 4, analysis, comparison, calculation of related data information; step 5, the display of the acquired foundation pit risk related information by adopting visualization means; step6, timely transmission of effective information to information demanders by adopting an Internet way; step7, recording of risk treatment means and treatment results proposed by the information demanders. By adopting an informatization way, the foundation pit risk related information is acquired, the storage, the extraction, the arrangement, and the analysis of the above mentioned information are facilitated; foundation pit data is timely updated; by adopting the constant accumulation and analysis of the foundation pit risk related information, a foundation pit risk theory is in dynamic adjustment, and therefore the risk management is more accurate and effective; the transmission efficiency and the transmission accuracy of the information are improved, and risk prevention early warning is provided.

The invention belongs to the field of power system protection and control and particularly relates to a current protection and threshold crossing risk monitoring method for an urban power grid including EV (electric vehicle) charge-discharge stations. Probability distribution of discharge powers of the EV charge-discharge stations is formed on basis of charge-discharge data information of the EV charge-discharge stations; short circuit current probability distribution of each current protector is calculated through Gram-Charlier series and a semi-invariant; a short circuit current threshold crossing severity index is calculated through a utility theory; current protection and threshold crossing risk indexes of the urban power grid including the EV charge-discharge stations are then calculated. According to the method, risk assessment is performed by a probabilistic power flow method on basis of the utility theory and a risk theory; normal current protection is effectively guaranteed for the urban power grid including EV charge-discharge stations, and the urban power grid can run safely and reliably.

The invention discloses a power grid dispatching operation risk evaluation method taking a weather factor into consideration. The method comprises the following steps: step 1, according to weather statistical data, historical statistical data of an equipment fault rate and a three-state weather model, calculating an equipment fault probability in a dispatching operation process respectively under a normal weather condition, a bad weather condition and an extremely bad weather condition; step 2, according to a system state in the dispatching operation process, obtaining a fault tree model; step 3, according to the fault tree model and a given risk consequence index, calculating a consequence of each step of operation, and determining whether the sequence is a development fault of the last step; and step 4, according to a risk theory, calculating a risk value of each step in the dispatching operation process and a total risk value. The method is reliable, is easily implemented and is convenient to promote.

The invention discloses a low frequency risk comprehensive evaluation method for nuclear power accessed to grid, which comprises safety risk evaluation indexes with plant-grid risks combined, a low frequency risk evaluation model integrating safety and economy between the nuclear power and the power grid, and a nuclear power low frequency risk evaluation method for a low frequency safety risk transformation ratio, an index safety risk value, a device low frequency risk sensitivity and the like. The low frequency risk indexes comprise a low frequency risk index for evaluating reduction of the system frequency on the plant-grid influence degree and a device risk index based on a plant-grid low frequency protection device; the low frequency comprehensive risk model is built based on a risk theory and a plant-grid side economic index is introduced, and quantitative analysis on the low frequency risk is realized; and the risk calculation method for the safety risk transformation ratio, the index safety risk value, the device low frequency risk sensitivity and the like is easy to compare and analyze, and a basis is provided for making a protection device parameter optimization scheme and a plant-grid coordination control strategy. The structure is rigorous and clear, and requirements of risk analysis and decision are met; and model parameters have clear meaning and are easy to acquire, the modeling process is clear, quick, convenient, efficient, accuracy and strong in practicability.

The invention belongs to the technical field of computer software, and discloses a resource environment bearing capacity measurement and risk management and control method based on the risk theory, which comprises the steps that after collected data are transmitted to a computer, data preprocessing, classification and storage are carried out, risk factor recognition of a resource environment is carried out through the short board technology, and a large database of the resource environment bearing capacity is established; health, property and life risks of the resource environment are calculated and classified according to the resource environment data stored in the computer; resource environment data stored in a computer are called, and a storage data set of resource bearing capacity is established; game analysis is carried out on the basis of benefits-cost ratio, and comprehensive evaluation on resource bearing capacity is carried out; and risk adaptation, transfer and emergency disposal schemes are formulated. According to the risk-based resource environment bearing capacity evaluation principle, the risk-based resource environment bearing capacity evaluation technical method system and evaluation criteria, new theories and key technologies are provided for resource environment bearing capacity evaluation, and a basis is provided for demarcation of three red lines in territorial space development.

The invention discloses a vulnerability assessment method for an electrical integrated energy system. The vulnerability assessment method comprises the following steps: S1, starting assessment; S2, calculating and inputting an estimated value of the branch removal possibility of the power transmission line; S3, calculating and inputting a branch removal possibility estimated value caused by the natural disaster; S4, calculating an estimated value of the possibility of branch removal caused by internal structure, technology and equipment factors, and inputting the estimated value; S5, calculating and inputting a transformer branch removal possibility estimated value; and S6, obtaining an evaluation value of the vulnerability of the electrical integrated energy system. According to the electric power system structure vulnerability analysis method based on the electrical betweenness and the risk theory, the effectiveness of identifying the vulnerable branches and the vulnerable nodes in system structure vulnerability evaluation by the electrical betweenness is verified.

The invention provides a quantitative optimization analysis method and system for uncertain factors of a comprehensive service station. The method comprises the following steps: constructing a probability distribution model of various uncertain factors of the comprehensive service station; introducing stochastic programming and scene analysis, converting comprehensive service station optimization scheduling containing the uncertain factors into optimization of a plurality of determined scenes, wherein each scene set is the probability of the running state of the comprehensive service station at the current time; and calculating expected loss by using a conditional value-at-risk theory, and measuring the influence of uncertain factor fluctuation on a decision target. According to the method, the probability distribution model of various uncertain factors of the comprehensive service station is constructed, the random programming theory and the conditional value-at-risk theory are applied, the influence of uncertain factor fluctuation on a decision-making target is measured, and a bidding model of the comprehensive service station for optimizing multi-type resource output in a market environment is established; the model gives consideration to the robustness and economy of the bidding decision of the comprehensive service station, can deal with severe scenes, and is more practical.

The invention discloses a risk quantification evaluation method for switch and knife switch operation processes. The method comprises following steps of (1), dividing operation states of a switch and a knife switch into three kinds of risk scenes of a successful state C1, an accident state C2 and a defect state C3, and calculating risk influence values of the switch and the knife switch in the successful state C1, the accident state C2 and the defect state C3; (2), calculating probabilities of the switch and the knife switch in the successful state C1, the accident state C2 and the defect state C3; and (3), carrying out risk quantification evaluation according to a risk theory. According to the invention, the actual switch and knife switch operation can be guided; and the method is very important in avoiding risks in the switch and knife switch operation, reducing risk coefficients of the switch and knife switch operation and maintaining safe, reliable and economical operation of an electric power system.

The invention discloses an active sensor management method based on a risk theory, and the method comprises the following steps: firstly, building a target risk model through the risk theory, and then giving a calculation method of a sensor radiation risk and a sensor tracking error to quantify potential loss, and then, establishing a target function with the minimum weighted sum of the two risks as an optimization target, and in order to obtain better combat benefits and improve the solving efficiency of the target function, using a convex optimization toolkit to solve the target function. According to the method, the model is established by using the risk theory, the target function is constructed according to the sensor radiation risk and the sensor tracking error, and the optimal solution of the target function is obtained by optimizing and solving the target function by using the convex optimization theory, so that the solving efficiency of the target function is improved.

The invention relates to an electric power system differentiation planning technology, in particular to a core backbone network frame construction method based on a risk theory, and the method comprises the steps: constructing an electric power system safety risk assessment index system based on the risk theory; calculating the weight of each index based on a CRITIC weighting method; and completing risk assessment through a probabilistic load flow calculation result, constructing a core backbone network frame search model by taking the minimum sum of the comprehensive risk level and the length of the core backbone network frame as an objective function; solving the constructed model based on an improved fireworks algorithm, and repairing the net rack connectivity through a Floyd-Warshall algorithm to obtain a core backbone net rack construction scheme. According to the method, risk factors are fully considered in construction of the core backbone network frame, the adverse conditions of voltage out-of-limit, power out-of-limit and the like are effectively improved, and the risk level of operation of the core backbone network frame is reduced. The risk level of the power system under the large-scale new energy access trend is reduced, and the disaster resistance of the system is improved.