42 results about "Failure detection and isolation" patented technology

The invention discloses a distributed fault detection method for an intelligent power distribution network. The method comprises the following steps that a protective range of each intelligent power distribution terminal is determined; each intelligent power distribution terminal communicates with an adjacent intelligent power distribution terminal in a peer-to-peer manner, and interacts network topology structure information of a position where the intelligent power distribution terminal is located; each intelligent power distribution terminal judges a fault position on the basis of a regional longitudinal comparison protection principle and according to fault information obtained by calculation of the acquired adjacent intelligent power distribution terminal; after a line with the fault position is determined, a switch type corresponding to the line is determined according to a network topology structure, and a corresponding fault isolation strategy is made according to the switch type. The method disclosed by the invention has the beneficial effects that each intelligent power distribution terminal can interact the fault information with the adjacent intelligent power distribution terminal in the peer-to-peer manner according to the current network topology structure, so that a faulty region is accurately and effectively isolated, and the requirements on quickness, flexibility and reliability of fault detection and isolation of the intelligent power distribution network are met.

Methods for reducing the resources needed to detect and identify faulty pseudorange measurements in a GNSS receiver are described. In a Receiver Autonomous Integrity Monitoring (RAIM) method, a position solution is calculated using a weighted least squares method on measurements from satellites of one or more GNSS constellations. A test statistic is calculated from residuals and a threshold is calculated based on a probability function. If the test statistic is greater than or equal to the threshold, a subset is selected from the set of pseudorange measurements using a metric indicative of possible measurement error. A measurement is selected from the subset using a metric indicative of signal strength or some other metric and discarded from the set of pseudorange measurements. If the number of measurements remaining in the set of pseudorange measurements is greater than five, the method loops back to the step of calculating a position solution.

The invention discloses an intelligent distribution network oriented distribution type fault detection and isolation system and a working method. The distribution type fault detection and isolation system comprises intelligent power distribution terminals arranged in each measurement point of the intelligent distribution network, and a management maintenance work station arranged in a transformer substation; the intelligent power distribution terminals are in peer-to-peer communication; and the intelligent power distribution terminals and the management maintenance work station are in master-slave mode communication. The intelligent distribution network oriented distribution type fault detection and isolation system has the beneficial effects that the management functions of the management maintenance work station on remote measuring, remote signaling, remote control and the intelligent terminals can be realized due to the communication between the intelligent power distribution terminals, and the communication between intelligent power distribution terminals and the management maintenance work station; and the intelligent power distribution terminals can realize peer-to-peer fault information interaction with adjacent intelligent power distribution terminals according to the current network topology so as to realize accurate and effective isolation for the fault regions, and satisfy the demands of rapidness, flexibility and reliability of the intelligent distribution networks on the fault detection and isolation.

Method for detecting faults in a device comprising the steps of receiving a plurality of performance parameters, applying the plurality of performance parameters to a first model to produce a plurality of estimated performance parameters, applying the plurality of performance parameters to a second model to produce a plurality of estimated device parameters, computing a plurality of residuals from the plurality of estimated device parameters, computing a plurality of distance measuring from the plurality of residuals, detecting at least one parameter deviation using the plurality of residuals and the plurality of estimated performance parameters, and setting at least one detection flag if the detected at least one parameter deviation is persistent.

The invention provides a multi-model-based high speed train suspension system multi-actuator fault detection and isolation method. The method involves a first bullet train, a trailer and a second bullet train and comprises the following steps that (1) a suspension system, of a two-bullet-train and one-trailer structure, of a train is modeled to obtain a suspension system model; (2) a fault model is built for each actuator of the suspension system of the two-bullet-train and one-trailer structure; (3) a sliding-mode observer matched with each fault model is arranged based on the corresponding fault model, and the corresponding residual quantity is generated; (4) a fault warning threshold value is generated according to the train operating environment and suspension system working conditions, and a logic controller is used for decision making for all residual quantities to judge whether an alarm needs to be given out or not and point out the fault occurrence position. The application of the fault detection and isolation technology is the effective way for improving the system reliability, and an alarm is given in time when a fault occurs, particularly, the fault occurrence position is pointed out when the multiple actuators break down, and fault screening and system maintenance are facilitated.

The invention discloses a multi-source self-adaptive fault-tolerant federated filtering integrated navigation system and a navigation method. The system comprises a strapdown inertial navigation system, a satellite navigation system, a Doppler velocity measurement system, a celestial navigation system, and a main filter and three sub-filters that are in information connection with the systems respectively; the three sub-filters are all in information connection with the strapdown inertial navigation system, and are connected to the main filter through a fault detection and isolation module, the strapdown inertial navigation system is connected to the fault detection and isolation module through a state transmitter, and an output result of the fault detection and isolation module passes through an information sharing factor calculation module, then the calculation result is input into the main filter; and the main filter outputs the fused information and synchronizes a fusion result tothe three sub-filters and the state transmitter. According to the system and the method disclosed by the invention, the state of each sub-filter can be tracked more accurately, and a more precise fusion result can be obtained.

The invention provides a novel detecting and isolating system for a fault of a RS-485 port, which comprises a bus and a plurality of slave nodes connected with the bus, wherein each of the slave nodes comprises an RS-485 communication circuit, an MCU (Micro Controller Unit) and a relay; the MCU is connected with a normally opened end of the relay and the RS-485 communication circuit; and the relay is connected with the RS-485 communication circuit and an RS-485 bus. The slave nodes of the novel detecting and isolating system for the fault of the RS-485 port can judge whether the RS-485 bus communication is abnormal or not. If the communication is abnormal, the slave nodes can automatically disconnect from the RS-485 system bus and can carry out data communication with the RS-485 communication circuit through IO ports of the slave nodes, so as to detect whether the RS-485 communication circuit can normally work or not.

The invention discloses a method and device for generating a center device relationship topology map based on data, and belongs to the technical field of computers. The method comprises the followingsteps: initializing a tree map root node to obtain a starting node for generating the topology map; creating a canvas for displaying scalable vector graphs in a browser according to the starting node;obtaining node data of a next level associated device from the background according to the node; calculating an X axis offset and a Y axis offset of the node on each layer of the canvas according tothe node data, and constructing a node offset table; and obtaining node location offset data from the node offset table, calculating an actual node location according to a unit length, and generatinga machine room device topology map. According to the method and device disclosed by the invention, the machine room device relationship topology map is generated in the browser by using the SVG technology, thereby improving the generation efficiency of the topology map, moreover, the device has a simple structure, is easy to manage and maintain, and is convenient to achieve fault detection and isolation when a fault occurs.

The invention relates to a fault-adaptive carrier rocket intelligent control semi-physical simulation method, and belongs to the technical field of carrier rocket semi-physical simulation. The methodcomprises the steps: step 1, establishing a carrier rocket six-degree-of-freedom simulation model including a kinetic model, a mass model, a gravitational attraction model, an aerodynamic force model,an engine model and a sensor model; step 2, establishing a GNC model of the carrier rocket comprising a navigation model, a guidance model and a control model; step 3, establishing a real-time faultdetection and isolation model; judging whether the engine has a fault or not according to the real-time fault detection and isolation model; step 4, planning an optimal trajectory curve of the rocketafter any fault. According to the invention, the adaptability to rocket faults is realized, a semi-physical simulation system based on a carrier rocket six-degree-of-freedom simulation computer and highly integrated rocket-borne comprehensive electronics is built, so that the semi-physical simulation verification of rocket intelligent control in a fault state is realized.

The invention discloses a fault detection and isolation method for an integrated navigation system of an unmanned aerial vehicle, which comprises the following steps of performing fault detection andisolation according to original data output by an IMU (Inertial Measurement Unit), and performing fault detection and isolation on each piece of measurement information to ensure high reliability of the integrated navigation system of the unmanned aerial vehicle. According to the method, the calculated amount is small, IMU faults and measurement faults can be detected in real time, sensors with faults are isolated, and the number of IMUs installed in a non-coaxial mode is not limited. According to the method, the IMU unit data source is directly detected, IMU faults can be prevented from beinginjected into the filter, it is guaranteed that the filter is not polluted by the faults, fault detection and isolation are carried out on each measurement, and the method is suitable for fault detection and isolation of various sensors with different rates.

The invention provides a polar zone centralized filter-based integrated navigation system residual vector fault detection and isolation method. In view of a polar zone integrated navigation system with a grid inertial navigation system as a basic navigation device, based on a residual X<2> test method, through designing a residual vector, a residual vector X<2> fault detection and isolation methodis designed, fault detection and isolation on a centralized filter are realized, and the reliability of the integrated navigation system based on the centralized filter group for the polar zone is improved. Compared with a federated filter, the centralized filter has better filter precision. The method enables the centralized filter to have the fault detection and isolation capability, and enhancement of the fault-tolerant capability of the integrated navigation system is realized on the premise of not sacrificing the filter estimation accuracy.

The invention provides a PHM-based middle and low voltage power distribution network operation and maintenance system and method. The system comprises a data information acquisition and processing module, a state monitoring and fault early warning module, a fault detection and isolation module and a power distribution network health state evaluation module. The zero-sequence voltage abrupt change energy E(k) of the neutral point of the power distribution network is used as a starting criterion of fault early warning of the power distribution network; when a certain feeder reaches an early warning level, a fault detection and isolation module is started, positive sequence current fault components measured by each terminal node on the fault feeder are used for fault direction discrimination and fault positioning, and the amplitude of each phase of voltage is used for fault type identification; and after a master station completes fault positioning and recognition, a small resistor is actively put into the neutral point of the power distribution network for fault isolation. The operation state of the power distribution system can be monitored in real time, the health state of the power distribution system is managed, and the operation efficiency and the operation and maintenance work level of the power distribution system are improved.