31 results about "Bond graph" patented technology

The invention discloses an IGBT fault diagnosis method for a traction drive system of a CRH5 type high-speed train, and the method comprises the steps: modeling a traction part bonding graph: respectively building a traction inverter model, a traction motor model, and a gearbox bonding graph model; carrying out system modeling: building a traction drive system model of a high-speed train, and simulating the operation states when the system is normal and an IGBT fault happens; building a global analysis redundancy relation: building a simplified system global analysis redundancy relation, obtaining a fault characteristic matrix, and analyzing a system fault propagation approach; carrying out fault diagnosis: enabling system output to be substituted into the global analysis redundancy relation, forming a residual error set and a consistency vector, comparing the residual error set and the consistency vector with the fault characteristic matrix, and detecting the health state of the system, and positioning an IGBT fault source. The method diagnoses the IGBT fault of the traction drive system of the high-speed train through employing a bonding graph method, builds the motor model through multiple bonding graphs, carries out the unified modeling of an electromechanical system, achieves the positioning of an IGBT element with a fault, and provides a solution for the modeling of the traction drive system of the CRH5 high-speed train and the diagnosis of the IGBT fault.

The invention discloses a numerical control machining parameter adaptive fuzzy control rule optimization method. The method includes the following steps: step1, parameter operation of a numerical control machine tool drive system is created, an input variable and an output variable of an adaptive fuzzy control model are confirmed, and a value taking interval is confirmed according to practical machining conditions; step 2, a drive system module of a numerical control machine tool is analyzed and confirmed, a bond graph method is utilized to obtain a simulative effect picture of corresponding change relations of an input language variable and an output language variable; step3, combining the step 1 with the step 2 and according to the simulative effect picture, the change relations among the variables are analyzed, and dynamic optimization is carried out on a fuzzy control rule list. According to the numerical control machining parameter adaptive fuzzy control rule optimization method, a power bond graph method is utilized to optimize fuzzy control rules. The numerical control machining parameter adaptive fuzzy control rule optimization method is used on on-line adaptive control of numerical control machining parameters, the control performance and the machining stability of a fuzzy controller are improved.

The invention discloses a model based IGBT open-circuit fault diagnosis method for a traction inverter of a CRH3 electric multiple unit. The method comprises the steps of (1) establishing a bond-graph model of the traction inverter; (2) deducing a system behavior constraint equation of the model; (3) based on the system behavior constraint equation, identifying the state of each current switch by utilizing a least square method; (4) performing difference operation on each IGBT pulse signal (represented by 0 or 1) given by a control system and the state (represented by 0 or 1) of each current switch to obtain six fault identification vectors; and (5) if an element in the fault identification vectors is greater than 0, indicating that an open-circuit fault occurs to a corresponding IGBT. According to the model based IGBT open-circuit fault diagnosis method for the traction inverter of the CRH3 electric multiple unit, when faults occur to any one or two IGBTs, the faults can be detected and positioned quickly and accurately; and the problem that a model based method cannot complete multi-fault identification in the field is solved.

The invention discloses a quick simulation analysis method for a radar antenna servo system. The quick simulation analysis method includes the steps that (1) parametric modeling of a bond graph is carried out, components in the system are simplified according to the modeling sequence of a drive motor, a transmission mechanism and a reflecting surface body and accordingly a bond graph model of the antenna servo system is built; (2) virtual prototype multi-rigid-body modeling is carried out, part rigid-body models in all links are sequentially built on the basis of the modeling theory that each solid body in the system corresponds to one rigid body in a multi-rigid-body model, the corresponding rigid bodies are combined according to a parametric model of the bond graph and accordingly a system design model is obtained; (3) a parameter synchronization mechanism is introduced, and design model parameters are transferred to the bond graph model synchronously by means of a design model information file; (4) a system mathematic model is deducted according to the system bond graph model. Mathematical modeling simulation, multi-rigid-body modeling simulation and bond graph modeling simulation methods are well combined, advantages are made use of and defects are avoided.

The invention discloses a Bayesian network-based high-speed rail traction system fault prediction method. The method comprises the following steps of: 1, establishing a closed-loop bonding graph model: adding a direct torque control module into an original bonding graph model; 2, building a Bayesian network: firstly determining nodes of a Bayesian network structure, determining the structure of the Bayesian network according to the causal relationship between the nodes provided by the closed-loop bonding graph model, and finally opening a closed loop in the Bayesian network; 3, data preprocessing: filtering and denoising the original signal, extracting features, monotonically screening and extracting deep features, and finally, carrying out k-feature extraction on the features; performingmeans clustering; and 4, fault prediction: carrying out supervised learning by using an EM algorithm, obtaining the state of an online measured value by using the data preprocessing method, and carrying out classification by using a Bayesian network to obtain the residual life range of the equipment. Equipment fault prediction can be realized, and the method is more practical and reliable.

The invention relates to an electric scooter fault diagnosis method, in particular to an electric scooter fault diagnosis and estimation method based on a bond graph model. Firstly, the model is established for an electric scooter, so that the bond graph model of the electric scooter is obtained, a redundant relationship is analyzed according to the bond graph model of the electric scooter, a residual error is generated according to the analyzed redundant relationship, a fault characteristic matrix is obtained, the parameter values of the bond graph model of the electric scooter are changed, whether the residual error exceeds a set threshold value or not is judged, if the residual error exceeds the set threshold value, an electric scooter system generates a fault, coherent vectors and thefault characteristic matrix are compared, a possible fault set is obtained, elements in the fault set and system original state variables are jointly estimated through an unscented Kalman filter method, and the actual fault of the electric scooter system is obtained. Fault parameters can be accurate to specific numerical values through fault identification, and a fault source can be diagnosed andisolated accurately in time.

The invention discloses a high-speed motorized spindle thermal error modeling method based on a bonding graph. The method comprises the following steps: 1, constructing a high-speed motorized spindle bearing temperature field bonding graph model; 2, constructing a motor stator temperature field bonding graph model; 3, constructing a motor rotor temperature field bonding graph model; 4, according to the specific structure of the high-speed motorized spindle, connecting the temperature field bonding graph models established in the steps 1 to 3 to establish a complete high-speed motorized spindle thermal error system temperature field bonding graph model; 5, establishing a thermal error mathematical model of the high-speed motorized spindle; and 6, performing system simulation according to the model, and analyzing to obtain the thermal error of the high-speed motorized spindle. According to the method, a bonding graph modeling method is adopted, all parts are convenient to connect and add, the high-speed motorized spindle system temperature field with various energy forms can be directly modeled and analyzed; therefore, the problem that singular points which cannot be analyzed are generated is solved, and the rapidity and accuracy of modeling, simulation and analysis of the high-speed motorized spindle system are improved.

The invention discloses a modeling method of a bond-graph-based movable mechanical arm system. The method comprises the steps of 1, constructing a driving motor and transmission mechanism bond graph model; 2,constructing a double-wheel differential type mobile robot mechanical system bond graph model; 3, constructing a series connection type mechanical arm mechanical system bond graph model; 4, according to the robot freedom degree, connecting the bond graph models established in step 1, step 2 and step 3, and establishing a complete robot system bond graph model by considering the force-bearing relationship between the system and the ground; 5, deriving a mathematic model according to the bond graph model; and 6, conducting system simulation and analysis according to the model. By means of the modeling method, errors caused by the operation that modeling and control are conducted on a mobile robot and a mechanical arm separately, but the coupling relationship between the mobile robotand the mechanical arm is neglected are avoided; the bond graph method is adopted, modeling and simulation problems of a robot system combining multiple energy forms are solved in a unified manner; and rapidness and precision of dynamics modeling, simulation and analysis of the robot system are improved.

The invention relates to the technical field of engineering design, in particular to an engineering design method for conducting automated evolution design on mixing field systems or various different field systems based on a bond graph tool and a genetic programming algorithm. The method includes the steps of assigning an embryo physical structure diagram, conducting user input, setting up an initial population of a genetic programming tree, conducting ontoanalysis, conducting evolution operation and ending judgment. Compared with the prior art, the design method is high in expansibility, wide in application range, high in efficiency, high in normalization and capable of designing a complex project meeting the requirements of a designer through an automated method.

The invention discloses an electric drive system multi-field coupling optimization method based on bonding graph modeling. The method comprises the following steps: S1, establishing a permanent magnetmotor bonding graph model; S2, establishing a speed reducer bonding graph model; S3, establishing an electric drive system bonding graph model, and deriving a state equation of the electric drive system bonding graph model; and S4, inputting simulation parameters, and correcting the electric drive system bonding graph model. By adopting the technical scheme, the energy transfer process of the electric drive system is clearly described, the dynamic characteristics of the electric drive system can be dynamically reflected in real time, and a theoretical basis is provided for the optimal designof the electric drive system.

The invention discloses a distributed fault diagnosis method for a circuit system. The distributed fault diagnosis method comprises: modeling is carried out on a circuit system and causal relationships between various parameters are configured to obtain a global diagnostic bond graph model of the circuit system; a minimum sub system based on each sensor is extracted from the circuit system by using all sensors in the circuit system as basic units and measuring values of sensors as local outputs of the circuit system to obtain local diagnostic bond graph models of all minimum sub systems respectively; according to the local diagnostic bond graph models of the minimum sub systems, a distributed analytical redundancy relationship is obtained, and the distributed analytical redundancy relationship is analyzed to obtain a distributed fault feature matrix; and on the basis of the distributed fault feature matrix, fault diagnosis is carried out. According to the invention, under the conditions of single fault and multiple faults, the performance of fault isolation is improved effectively; the complexity of subsequent fault component identification is reduced; and the diagnostic speed anddiagnostic accuracy of the fault are enhanced.

The invention discloses a speed reducer bonding graph model optimization method based on a six-degree-of-freedom gear engagement model. The speed reducer bonding graph model optimization method comprises the following steps: S1, establishing a six-degree-of-freedom first-stage gear pair engagement kinetic model; S2, establishing a six-degree-of-freedom first-stage gear pair bonding graph model; S3, deducing a state equation of the first-stage gear pair bonding graph model; S4, establishing a speed reducer bonding graph model; S5, deriving a state equation of the speed reducer bonding graph model; S6, performing simulation analysis on the state equation of the speed reducer bonding graph model, and correcting the speed reducer bonding graph model. By the adoption of the technical scheme, the built gear pair bonding graph model and the built speed reducer bonding graph model can accurately analyze the characteristics of the speed reducer and the characteristics of other gear transmissionmechanisms, and a theoretical basis is provided for optimization design of the speed reducer and other gear transmission systems.

The invention discloses an active fault-tolerant control method for a nonlinear electromechanical system. The active fault-tolerant control method comprises the following steps: establishing an uncertainty diagnosis bonding graph model of the system; deducing an analysis redundancy relation and a dynamic model of the system according to the uncertainty diagnosis bonding graph model; designing and optimizing an adaptive threshold based on a particle swarm optimization algorithm to improve the fault detection performance under the parameter uncertainty condition; based on a recursive terminal sliding mode theory, a recursive terminal sliding mode control law, namely a closed-loop control law, of the system is designed, and load position tracking of the system in a healthy state is achieved; aiming at a parameter fault of the system, estimating an unknown parameter fault item in real time by utilizing an adaptive fuzzy system, compensating an estimated value into a control law, and designing an adaptive fuzzy recursive terminal sliding mode control law, namely a fault-tolerant control law, of the system; and when a parameter fault occurs in the system, the closed-loop control law is switched to the fault-tolerant control law, so that active fault-tolerant control on the parameter fault of the system is realized.

The invention discloses a downstream pressure compensation system parameter sensitivity analysis method, which comprises the following steps of: 1, constructing a power bonding graph model of a downstream pressure compensation system; 2, deducing a state equation of a downstream pressure compensation system; and 3, deducing a parameter sensitivity differential equation of the downstream pressure compensation system, and determining the parameter sensitivity. The invention provides a post-valve pressure compensation system parameter sensitivity analysis method, which establishes a post-valve pressure compensation system mathematical model based on a power bonding graph theory so as to solve the sensitivity analysis problem of a post-valve pressure compensation system, and aims to provide a post-valve pressure compensation system parameter sensitivity analysis method. And a research foundation and a theoretical basis are laid for analyzing key parameters influencing the dynamic characteristics of the load-sensitive proportional multi-way valve in the pressure compensation valve and optimizing the dynamic characteristics of the load-sensitive proportional multi-way valve and design parameters of the pressure compensation valve.

The invention discloses a dynamic simulation system and method for an integrated energy system. The integrated energy system comprises a power network, a heat supply network and connectable coupling equipment connected between the power network and the heat supply network. The electric power network and the heat supply network are mutually coupled through the connectable coupling equipment, and the electricity and heat utilization requirements of users are met at the same time. According to the method, on the basis of a bonding graph theory, dynamic characteristics of the regional integrated energy system are combined, and a bonding graph model of main basic elements of the regional integrated energy system is established. According to the method, a state equation of the regional integrated energy system is further constructed and solved, a dynamic simulation result of the regional integrated energy system can be obtained by utilizing an output equation, the dynamic characteristics of the regional integrated energy system are fully considered, numerical simulation and analysis are performed on a certain actual regional integrated energy source through an example, and the dynamic simulation result of the regional integrated energy system is obtained. And an effective theoretical basis is provided for safe and stable operation of the regional comprehensive energy system.