786 results about "Fault model" patented technology

Methods and apparatus are provided for analyzing a complex system that includes a number of subsystems. Each subsystem comprises at least one sensor designed to generate sensor data. Sensor data from at least one of the sensors is processed to generate binary evidence of a sensed event, and complex evidence of a sensed event. The complex evidence has more sophisticated mathematical properties than the binary evidence. The complex evidence comprises one or more of: a condition indicator (CI), a health indicator (HI), and a prognostic indicator (PI). A system fault model (SFM) is provided that defines statistical relationships between binary evidence, complex evidence, and an underlying failure mode (FM) that is occurring in the complex system. The binary evidence and the complex evidence are processed to identify failure modes taking place within one or more of the subsystems. Based on the binary evidence and the complex evidence and the SFM, diagnostic conclusions can be generated regarding adverse events that are taking place within the complex system, and prognostic conclusions can be generated regarding adverse events that are predicted to take place within the complex system.

The embodiment of the invention provides a modeling method of an early warning model of mixed failures and a modeling system. The modeling method provided by the invention comprises the following steps of: generating a function analyzing module on the basis of HAZOP (Hazard and Operability Analysis) or FMEA (Failure Mode and Effects Analysis); generating a degeneration analyzing module on the basis of FMEA analyzing results and a theory of stochastic processes; generating an accident analyzing module according to state monitoring data and maintenance action information; generating an action analyzing module according to output results of the function analyzing module and the degeneration analyzing module through combining a DBN (Dynamic Bayesian Network) theory; taking the output of the accident analyzing module as an inference evidence and utilizing a DBN inference algorithm to process forward and backward inferences in the same time period to generate an evaluating module for outputting factors and consequences of system failures; taking the output results of the evaluating module and the accident analyzing module as the inference evidence and utilizing the DBN inference algorithm to process forward and backward inferences in the different time periods to generate a predicating module for outputting prospective degeneration tendencies of each member of the system. The model provided by the invention can be used for tracking the failure factors of the system and inferring possible failure consequences and probability.

The invention discloses a fault structure three-dimensional modeling method. The method comprises the steps that fault data are integrated in a three-dimensional visualization system; fault control points are extracted and a fault line is explained and formed; connection analysis of multiple conditions and fault line and fault attribute revision are carried out; the relationship between faults is calculated, and a fault network which reflects the topology structure is established; intersection is carried out on fault faces and a constructed initial stratum model to acquire an initial intersection line of the stratum and the faults; fault distance calculation is carried out on each fault point on the initial intersection line, and a three-dimensional fault line with upper and lower walls is acquired; weight setting is carried out on produced fault data of various kinds, and then fault face fitting is carried out to form a fault face network; and stratum model construction is carried out. Data detection can be effectively carried out. The accuracy of a fault model is ensured. The fault structure three-dimensional modeling method can be applied to petroleum, geology and other fields.

Simulation test equipment for validating the reliability of satellite attitude control and a test method thereof belong to the field of satellite attitude control. The test equipment comprises a ground simulation support module, a fault injection module and a satellite-born module, wherein, the ground simulation support module includes a monitoring terminal, a satellite model, a signal exciting source and a moment reverse-solution unit; the fault injection module includes an analog-to-digital converter, a signal transfer circuit, a fault injection processor, a man-machine interface unit and a digital-to-analog converter; and the satellite-born module includes a sensor, a satellite-born controller and an actuator. The test method comprises the following steps of: fault model setting; satellite initialization; orbit and attitude information renewal; the satellite-born controller collects signals of the sensor and outputs actuator command signals to the fault injection module; the actuator receives actuator pseudo command signals and outputs feedback signals to the fault injection module; the moment reverse-solution unit collects the pseudo feedback signals output by the fault injection module and outputs moment control signals to the satellite model. The equipment and the method of the invention have high feasibility and high performance-price ratio.

The invention presents a design method of a four-rotor fault-tolerant controller based on a nonlinear observer. The method includes the following steps: establishing a dynamic model of a four-rotor unmanned aerial vehicle (UAV), and dividing the UAV system into an attitude subsystem and a position subsystem; for the attitude subsystem, establishing a fault model, designing a nonlinear fault observer, carrying out real-time detection and online estimation on an unknown actuator fault, and designing a fault-tolerant controller based on a fast non-singular terminal sliding mode method by using the obtained fault estimation information; and for the position subsystem, inversely solving the control rate and the desired attitude angle of the position subsystem by combining a backstepping methodand a sliding mode method and designing an intermediate virtual quantity. A four-rotor UAV is enabled to track the desired position and yaw angle even when the actuator fails, so as to ensure the stability of the pitch angle and roll angle.

The invention provides a method and device for diagnosis and early warning of vehicle faults. The method includes the steps of establishing statistic models corresponding to various operation parameters in vehicles respectively according to the operation parameter data of a large number of vehicles, obtaining the operation parameter data corresponding to various fault types according to the maintenance records of the vehicles, determining parameter status data corresponding to the operation parameter date according to the statistic models, for each fault type, establishing a statistic model of the corresponding operation parameter status data to obtain the fault model, obtaining the operation parameter data reported by the vehicles in real time, determining the parameter status data corresponding to the operation parameter data according to the statistic model, performing abnormal alarm when abnormal operation parameters exist, determining whether the vehicles are going to break down or break down according to the fault model, and performing fault early warning or alarm when the vehicles are going to break down or break down. The method and device achieve automatic diagnosis and early warning of the vehicle faults.

The invention discloses a quad-rotor UAV fault tolerance control method based on an adaptive fault estimation observer, and belongs to the field of aviation aircraft control. The method comprises thata fault model of a quad-rotor attitude system is established according to a dynamic model of a quad-rotor UAV by considering a performer fault of a UAV system; a performer of the UAV includes four rotor motors in practicality, faults correspond to the four rotor motors, the fault model is processed, the faults are divided into two groups decoupled mutually, and a final attitude fault model is obtained; according to the provided fault model, the adaptive fault estimation observer is designed, corresponding adaptive laws are provided, the performance fault is estimated, and an H(infinite) method and an interval matrix method are used on external disturbance and parameter nondeterminacy respectively in the design process; and an attitude system error fault model is obtained on the basis of the fault model, a dynamic output feedback fault tolerance controller is designed on the basis of a fault estimated value, and fault tolerance control of the quad-rotor UAV is realized. Influence of the performer fault on performance of the quad-rotor UAV can overcome, and the safety and reliability of the UAV in the flight process are ensured fully.

An operation management apparatus monitors the performance information of a system executing services and extracts correlation variants of the performance information, thus allowing the management to detect and localize performance-degrading faults of the system. It is determined whether or not the range of correlation collapse ascribed to the performance information falls within the normal range of correlation collapse measured in the normal operation of the system. A history is retained with regard to the range of correlation collapse ascribed to the performance information which does not fall within the normal range of correlation collapse. It is determined whether or not the history accumulating the predetermined number of ranges of correlation collapse approximates to the fault range of correlation collapse measured in the faulty operation of the system, thus discriminating a fault model on the basis of the performance information.

The invention discloses an embedded satellite-borne fault-tolerant temperature control system and a verification method thereof. The system comprises a satellite management computer, an on-satellite temperature control system and a ground monitoring and fault injection computer; the on-satellite temperature control system comprises a temperature control calculation host machine, a temperature control calculation standby machine and an environmental simulation computer; and the temperature control calculation host machine and the temperature control calculation standby machine are temperature control computers. The verification method comprises the following steps of: 1, initializing a file allocation; 2, initializing the system; 3, beginning simulation; 4, injecting and executing a fault; 5, processing redundant fault tolerance; 6, monitoring the ground and evaluating the fault; and 7, evaluating a fault model and a redundancy strategy of the temperature control system. The fault injection and the verification process of the whole running stage of the real satellite-borne temperature control system are completely realized; and the method is simple, convenient and reliable, and greatly reduces the test time and expense for the practical system.

The invention discloses a method and a system for track traffic failure recognition based on improved Bayesian algorithm. The method comprises the following steps of: 1) determining various failure modes and corresponding monitoring values of each traffic device according to circuit structure of the traffic device, and building a failure model aiming at each failure mode and corresponding monitoring value; 2) recognizing a parent child relation among the monitoring data according to the failure model, thus obtaining a standard failure sample data; 3) training with the standard failure sample data through a Bayesian algorithm to obtain a failure recognition model, wherein weight of a parent node in the failure recognition model of each failure mode is greater than that of a child node; 4) monitoring and acquiring various monitoring values of the traffic device in real time, and recording time sequence of the monitoring values; 5) recognizing data through the failure recognition model, and determining corresponding failure. By the method and the system, accuracy of failure recognition is improved, failure repair time is reduced, the device can perform failure self-diagnosis, and traffic safety is guaranteed in the operation and maintenance aspect and the device aspect.

The present invention relates to a method, a computer program product and a system for performing functional formal verification. Error detection logic is verified by injecting errors in a hardware design description without any changes to the original design description. With the present invention both permanent and transient faults can be modelled, and the complete error space can be covered for all types of fault models that can be used at the RTL. The number of detected design errors is used to determine the overall coverage in relation to the number of injected errors. The error injection is prepared by adding additional circuits to an RTL netlist representation of the hardware logic design. Signal values for selected signals related to the error detection logic are compared for a modified netlist representation and for the original netlist using a formal verification tool.

The invention provides a method for diagnosing a fault by a functional fault directed graph, which can be applied to the field of fault diagnosis for some systems of aircrafts (such as an air source system, an anti-icing system and an air-conditioning system of an airplane gas path). The method comprises the steps of: decomposing a diagnosis object system to determine component relation and build a system structural model, confirming the corresponding input and output based on the component functions, determining the component fault model, analyzing fault propagation path and influence relation, setting test points and test information of a sensor, monitoring parameter variation that indicates the potential fault, forming an FF-SDG model, and at last, searching the potential fault source by a hierarchical policy inference method based on the FF-SDG model to perform fault diagnosis. The method can quickly and effectively find out the system fault source of the aircraft system, discover the fault cause, and make up shortage of the fault diagnosis technique based on manuals and cases when some fault cannot be predicated and the knowledge is difficult to be acquired by domain experts.

The invention discloses a near spacecraft fault diagnosis and fault-tolerant control method. Firstly, a dynamical model of an attitude control system of a reentry phase of a near spacecraft is established and the dynamical model of the attitude control system is transferred to a nonlinear equation in a general type through coordinate transformation; secondly, a fault model with actuator invalidation and actuator dynamic damage existing simultaneously is established; thirdly, real-time online estimation of self-adaption estimation observer to actuator dynamic damage factors and actuator invalidation factors is respectively established; and finally a sliding module fault-tolerant controller is designed through the estimated actuator dynamic damage factors and the estimated actuator invalidation factors and parameters of the controller is updated in real time. According to the near spacecraft fault diagnosis and fault-tolerant control method, in the condition that when the actuator dynamic damage and the actuator invalidation occur simultaneously in a flight control system, fault information can be estimated rapidly and accurately, strong fault-tolerant capacity is achieved and an expected requirement of the flight control system is reached.

A method and system for developing fault models from structured text documents, such as service procedures. A service procedure or other structured text document is parsed using diagnostic rules to extract symptoms, failure modes, and correlations. Testing procedures and repair instructions are also parsed to create a fault tree and identify additional symptoms and failure modes. Reachability analysis is then used to find hidden dependencies in the fault tree, thus yielding additional correlations. The resultant symptoms, failure modes, and correlations are then assembled into a fault model, which can be used for real-time fault diagnosis onboard a vehicle, or for off-board diagnosis at service shops.

Methods, storage mediums, and apparatuses for evaluating the reliability of Three-Dimensional (3D) Network-on-Chip (NoC) designs are described. The described embodiments provide a 3D NoC specific fault-injector tool which is able to model logic-level fault models of 3D NoC specific physical faults in 3D-NoC platform. These embodiments automate the whole process of static and dynamic fault injection base on the user preference and reports the specific reliability metrics for 3D NoC platform as a single tool. The described embodiments can be used for the reliability evaluation and effectiveness of fault-tolerant designs in any of the 3D-many core designs such as manycore systems in different ranges of application from embedded systems in cellphones to larger systems which can be used in next generation of autonomous cars or hypercube memory cells.

The invention discloses a power distribution network fault processing method based on multi-source information fusion. The method includes five steps of 1) multi-source information searching, 2) fault data information collection, 3) fault model matching, 4) fault location and 5) fault processing. According to the method, a fault source is located by means of multi-source information collection and information matching, then fault processing and disclosing are conducted, the specific fault source can be accurately and timely located when operation faults of a power distribution network occur, corresponding processing is conducted, an auxiliary decision making function is provided for first-aid repairing and management of the faults, automation building of the power distribution network can be promoted quickly, and good application prospects are obtained.

Provided are a fault detector and a fault detection method for an attitude control system (ACS) of a spacecraft. The fault detector includes a first interacting multiple model (IMM) fault detection block for generating a normal model filter of the plurality of actuators and a plurality of upper level filters including fault model filters corresponding to the respective actuators, and detecting faults of the plurality of actuators using an IMM estimation technique from the plurality of upper level filters, and a second IMM fault detection block for generating a plurality of lower level filters each including a fault type model filter of the fault-detected actuator in the first IMM fault detection block, and detecting a fault type of the failed actuator using the IMM estimation technique.

The invention provides a flight control simulation system with fault diagnosis capability for an unmanned helicopter. The flight control simulation system with fault diagnosis capability for an unmanned helicopter comprises a simulation general control console, a simulation computer, a flight control management system, a sensor system, physical effect equipment, a servo system, a remote control and remote measurement system, and a task load system, wherein the simulation general control console controls the simulation computer to carry on a power on test, model generation and injection of fault model; the simulation computer selects simulation and interference model and simulates fault injection to carry on flight simulation; the flight control management system receives the information of sensors and the remote control and remote measurement system; the servo system realizes the real reaction of an operating mechanism; and the sensor system transmits the acquired sensor information to the flight control management system. For the flight control simulation system with fault diagnosis capability for an unmanned helicopter, the simulation computer can be embedded into different aircraft mathematical models, so that simulation of a plurality of aircrafts can be realized. For the flight control simulation system with fault diagnosis capability for an unmanned helicopter, the servo system and the sensor system can access a real steering engine of aircraft and real sensors so as to develop the steering engine of aircraft, to make a test flight for the steering engine of aircraft, and detecting working of the sensors.

The invention discloses a high-voltage circuit breaker fault diagnosis method based on an improved BP neural network. The method specifically comprises the steps of classifying collected samples, withclass tags, of a high-voltage circuit breaker into training samples and test samples, then building a BP neural network model based on a breeding algorithm and a particle swarm optimization algorithm, and after the training samples are used for performing training, performing decoding to generate new connection weight and threshold value; performing control by applying an iteration controller, enabling the two algorithms to carry out information interaction every multiple generations, and obtaining an optimal global parameter, wherein contents of the information interaction is relevant information of an optimal particle seed; and decoding an obtained global optimal solution, replacing all weight value and threshold value parameters of an original BP neural network, building an optimized high-voltage circuit breaker fault model, performing fault classification on the test samples, and outputting a result. According to the method, the BA and PSO algorithms are used for replacing an error back propagation-based network learning process to optimize the connection weight and the threshold value of the BP neural network, so that the fault diagnosis precision is effectively improved.

The invention discloses a dynamic correction method for reliability assessment of a large-sized oil-immersed power transformer; a transformer oil-paper insulating system is used as an assessment object, and two processes are involved; in the first process, with hotspot temperature calculation as the core, an HST-based (hotspot temperature) transformer aging fault model is established in conjunction with Weibull distribution and Arrhenius reaction law, winding HST is acquired by calculating, and fault rate gamma of the transformer oil-paper insulating system is solved; in the second process, with gray target correction analysis via dissolved gas in oil as the core, a relationship between transformer health state and its predicted life is established via grey theory, equivalent HST value is obtained, dynamic correction is provided for the basic model in the first process, and it is ensured that the assessment value is capable of well tracing and reflecting actual reliability level of the transformer. By using the method, it is possible to effectively solve the problems that, for instance, a transformer reliability analysis model has low accuracy and is difficult to popularize and apply.

The invention discloses a method for simulating faults of a power transformer. According to a current mode and method for simulating the internal faults of the transformer, a returned transformer is commonly utilized to conduct fault simulation tests, or the fault stimulation tests are directly conducted in oil in the transformer, workload is large, fault modules need to be frequently replaced, and the simulation effect is poor. According to the method for simulating the faults of the power transformer, an electric power simulation transformer structure and a transformer fault model are used as the foundation, generation, disappearance and intensifying of transformer partial discharge faults and winding deformation faults are directly controlled outside a transformer body through an external regulation control method, and regulation can be safely conducted in the boosting process. By the adoption of the method for simulating the faults of the power transformer, the trouble of replacing the fault model in the fault simulating process is avoided, generation time and intensity of the faults in the boosting process can be conveniently regulated and controlled, and the method is accurate and efficient.

The invention discloses one power system broad measurement system PMU device optimization method, wherein, the current method concentrated on small PMU for total observation and this invention considers the minimum generation tree method to improve PMU system robust property on N-1 false without impact on multiple linkage.

Cell-aware fault models directly address layout-based intra-cell defects. They are created by performing analog simulations on the transistor-level netlist of a library cell and then by library view synthesis. The cell-aware fault models may be used to generate cell-aware test patterns, which usually have higher defect coverage than those generated by conventional ATPG techniques. The cell-aware fault models may also be used to improve defect coverage of a set of test patterns generated by conventional ATPG techniques.

A system and method for providing component and sub-system state of health prognosis in a complex system using fault models and component aging models. The method includes determining a current state of health value for a sub-system using fault signature test results and determining current state of health values for a plurality of components in the sub-system using the fault signature test results. The method also determines current state of health values for components in the system that cannot use fault signature test results using a first probability model and the current state of health values for the plurality of components. The method determines predicted future state of health values for the components in the sub-system using component aging models and determines a predicted future state of health value for the sub-system using a second probability model and the future state of health values of the components.

A functional coverage based test generation technique for pipelined architectures is presented. A general graph-theoretic model is developed that can capture the structure and behavior (instruction-set) of a wide variety of pipelined processors. A functional fault model is developed and used to define the functional coverage for pipelined architectures. Test generation procedures are developed that accept the graph model of the architecture as input and generate test programs to detect all the faults in the functional fault model. A graph model of the pipelined processor is automatically generated from the specification using functional abstraction. Functional test programs are generated based on the coverage of the pipeline behavior. Module level property checking is used to reduce test generation time.

A system to and method of monitoring a condition of a process tool. The system monitors a condition of a process tool to correctly detect a faulty operation or malfunction of the process tool. The system to monitor the condition of the process tool includes a first model storage unit to store one or more good models generated by data associated with the process tool, a second model storage unit to store one or more faulty models generated by the data associated with the process tool, a model selector to receive tool data from the process tool, and to select one of the good models and one of the faulty models in association with the received tool data, and an error detector to receive process data from the process tool, to compare the received process data with the good and faulty models selected by the model selector, and to estimate a condition of the process tool.

The invention discloses a rigid spacecraft performer multi-fault diagnosis and fault tolerance control method. According to the method, the kinetic and dynamic model of a rigid spacecraft attitude control system is put forward, a fault model for existing of both the performance failure fault and the deviation fault of a rigid spacecraft is established, and then a fault detection observer adopting the adaptive threshold technology and a fault estimation observer based on the adaptive technology are respectively established so that online real-time detection and estimation of the fault time and the concrete situation of the fault can be realized, and finally a backstepping sliding mode fault tolerance controller is designed according to fault information established by the fault estimation observer. Attitude stabilization control of the rigid spacecraft under the condition of the performer efficiency damage and the deviation fault can be realized, and the influence of external disturbance on the system and the observers can also be considered in the design process. Besides, the fault detection observer and the fault estimation observer can be independently designed so that the engineering application can be more easily implemented.

The invention discloses a regional distributed photovoltaic fault diagnosis system and method for an access power distribution network. The system comprises a fault information detection sub-system, a fault data processing sub-system, a fault recognition sub-system, a fault model base sub-system, a fault alarm display sub-system and a fault feedback sub-system, wherein a photovoltaic grid connected point and power grid information are automatically obtained through the fault information detection sub-system and the fault data processing sub-system; fault information screening is carried out through classification, analysis and conversion; and the system is capable of automatically judging the fault type, analyzing the fault reasons, locating the fault position, automatically alarming at a fault point after judging the fault, and displaying detailed fault information according to the fault information processing result. The regional distributed photovoltaic fault diagnosis system provides a support for establishing a distributed photovoltaic power distribution network management system, and the operation security of the power grid is ensured.

The invention provides a mixed failure detection diagnosis method based on logical deduction and failure identification. The method comprises the following steps of: acquiring a failure causal relationship and historical failure data of a system to be detected, establishing a failure tree of the system to be detected, and determining the reliable distribution of each event node of the failure tree; acquiring a plurality of latent failure modes of the system to be detected, respectively establishing failure models which correspond to a plurality of latent failure modes, and thus obtaining a plurality of latent failure models; establishing association relationships between the failure tree and a plurality of latent failure models of the system to be detected; and when the system to be detected fails, detecting the current failure mode, and thus obtaining a diagnosis result of the current failure mode according to the association relationship between the current failure model which corresponds to the current failure mode and the failure tree. By adoption of the method, failures of an aircraft can be accurately detected and diagnosed, specific parts which fail are found, the accuracy and identification capacity of failure detection diagnosis are improved, and foundation is provided for maintenance of the aircraft.

The invention discloses a high-speed train traction transmission control system real-time fault simulation platform comprising four parts of a real-time simulator, a fault injection unit FIU, a physical traction transmission control unit TCU and a real-time data acquisition and monitoring unit. The real-time simulator comprises PC-dSPACE and real-time simulation software and is used for normal model and fault model simulation of all components in a traction transmission control system and real-time simulation monitoring; the fault injection unit FIU comprises virtual and physical parts and is used for realizing fault injection and level transformation of all types of faults of all components in the traction transmission control system at a signal level; the physical traction transmission control unit TCU is used for realizing feedback signal decoding and controlling generation of PWM signals and a protection function of the traction transmission control system; and the real-time data acquisition and monitoring unit is used for real-time simulation state monitoring and functions of data monitoring, storage control and historical data viewing of the whole platform.