154results about How to "In line with actual operating conditions" patented technology

The invention discloses a method and a system for dynamically setting a performance index threshold of IT equipment. The method is characterized by comprising the steps of acquiring historical index data of each performance of the IT equipment; according to the historical index data, calculating the index threshold interval of each performance through a unary linear regression equation and a floating coefficient; and setting the upper limit and the lower limit of the index threshold of each performance according to the threshold interval. The method and the system provided by the invention can dynamically calculate and set the performance index threshold of the equipment, thereby improving abnormity warning accuracy of monitoring equipment.

The invention provides a random reactive optimization method for a power distribution network including a wind power plant, which is used for eliminating adverse effects caused by various undetermined factors of the power distribution network and keeping the power distribution network run in a qualified voltage state. The method comprises the following specific steps: firstly, establishing a probability calculation model considering various random factors; secondly, establishing determining trend including a fan equivalent circuit, establishing a random trend model for the power distribution network including the wind power plant in combination with a semi invariant and Gram-Charlier series expansion method, and solving the voltage of each node and the probability distribution of reactive output of a generator; and lastly, establishing a reactive optimization model including the wind power plant by taking the voltage of each node and the probability distribution of the reactive output of the generator as the chance constraints of reactive optimization, taking the reactive output limit of the wind power plant as a constraint condition and taking a minimum active consumption expected value as a target function, and solving by using a genetic algorithm.

The invention discloses a fluctuation quantity method-based user side harmonic emission level practicality estimation method, belongs to the field of power quality harmonic treatment, is used for dividing rights and liabilities of harmonic pollution on a power supply side and an electricity side and belongs to a theoretical method practicality technology. The invention provides a complete processfor estimating the user side harmonic emission level by employing a fluctuation quantity method, provides a method for quantizing deviation between a power supply side harmonic impedance amplitude estimated value and an actual value, provides power supply side harmonic impedance amplitude estimated value accuracy for engineering, and easily and quantitatively judges whether the estimated value meets the requirement on engineering accuracy. In the method, various problems which possibly exist in actual engineering are considered theoretically. The conception of the time-varying dynamic phasor-based fluctuation quantity method is stated, the conventional harmonic impedance estimated value algorithm is improved, the least squares fitting algorithm which is wider in applicability and higher in accuracy is provided to estimate power supply side harmonic impedance; therefore, a practical flow more accords with actual operating conditions of a power system.

The invention discloses a static safety risk assessment method for an AC-DC hybrid micro-grid in island operation. The method comprises the following steps of: simulating the N-1 open-circuit fault ofthe AC-DC hybrid micro-grid in island operation with a given topology; performing a disconnection analysis to obtain an island system with the fault disconnected and the unrecoverable power loss loadin a fault area; establishing a probability distribution model of the random failure of an interlinking converter and a distributed generation device, the random output of an intermittent distributedgeneration device, and the load random fluctuation, performing Monte Carlo sampling to obtain a random input variable sample value; performing regional load-shedding operation on the island system toobtain the power loss load in a non-fault area, and performing conventional power flow calculation by using an accelerated LM algorithm with non-monotone linear search (ALMNL); and obtaining the probability distribution of each static safety risk indicator. The method of the invention can assess the static safety risk level of the AC-DC hybrid micro-grid in island operation, is an effective method for researching the static safety reliability of the AC-DC hybrid micro-grid in island operation, and provides technical support for the planning and operation of the AC-DC hybrid micro-grid.

The invention discloses a method and a system for intelligently identifying the operation state of an inhaul cable. The method is to respectively detect vibration frequencies before and after loading through a sensor arranged on the inhaul cable to carry out FFT conversion and related calculations respectively, thereby acquiring cable force, bending rigidity and rotational restrict stiffness at two ends of the inhaul cable. The method and the system have the advantages of simplicity, easy realization, high precision and small power consumption.

The invention provides a power system cascading failure simulation method based on a unified power flow controller and belongs to the technical field of power system security and reliability protection. A computer is used for determining the installation position of the unified power flow controller in a power system firstly, determining an active power flow betweenness threshold value of each node of the power system, performing power system cascading failure simulation based on the unified power flow controller and finally calculating measurement index for reflecting severity of cascading failure through procedures. The power system cascading failure simulation method gives consideration to power flow directivity and the operation mode of the system, optimizes the installation position for installing the unified power flow controller, effectively performs line parameter regulation while meeting safe operation constraints of the power system, and can reflect the propagation process of the cascading failure of the power system actually. The power system cascading failure simulation method based on the unified power flow controller can be widely applied to the cascading failure simulation of the power system, is particularly suitable for the cascading failure simulation of a large-scale complicated power system, and provides a scientific basis for preventing occurrence of the cascading failure of the power system.

The invention provides a method for implementation of micro-grid probability load flow analysis. The method includes the steps: numbering each node in a micro-grid, and forming a node admittance matrix according to micro-grid system data; working out semi-invariants of each stage of injection power according to probability distribution of each node injection power; aiming at uncertainty node injection powers, using the statistic method to obtain a mean value of micro-grid load flow and obtain a Jacobi matrix mean value of the last iteration; obtaining semi-invariants of each stage of system state variables according to the semi-invariants of each stage of each node injection power and the Jacobi matrix mean value of the last iteration; working out each coefficient of Gram-Charlier stages corresponding to a probability distribution function according to the semi-invariants of each stage of system state variables; approximately representing state variable probability distribution by means of Gram-Charlier stage truncation, and working out probability of events such as threshold crossing. Micro-grid probability load flow solution is realized by means of the conception of probability and mathematical statistics of the semi-invariants and the Gram-Charlier stages, uncertainty can be reflected, and micro-grid planning and evaluation on the micro-grid by operators can be facilitated.

The invention relates to a day-ahead optimization scheduling method considering a space-time correlation constraint of a wind farm, comprising the steps of: 1) building a robust unit commitment mathematical model which considers a power generation cost and a wind curtailment cost; 2) for a space clustering effect and a time smoothing effect of wind power, building a uncertainty set considering space and time constraint of the wind power; and 3) decomposing the mathematical model into a unit commitment main problem, a security feasibility inspection sub-problem and a wind power maximum utilization sub-problem, establishing a coupling relationship between the main problem and the sub-problems through a C&CG (Column and Constraint Generation) algorithm, and performing solving to obtain an optimization scheduling scheme. In comparison with the prior art, the day-ahead optimization scheduling method of the invention has the advantages of quick speed, reliability, high applicability, comprehensive consideration, good optimization effect, and so on.

The invention relates to an electric vehicle grid-connected scheduling method considering classification characteristics. The method is characterized by comprising the steps of (1) obtaining a probability density function of vehicle in time (tin(c,v), leave time tout (c,v) and daily mileage d(c,v) of travel characteristics of various types of electric vehicles, (2) using synchronous back substitution to carry out scene reduction on a sample scene R(v) and obtaining a reduced scene and a corresponding scene probability, (3) establishing a random unit combination model containing electric vehicles with thermal power unit total cost Fcost minimum as a scheduling target function, and linearizing nonlinear conditions in the model, and (4) using a mixed integer programming method to carry out solution and obtaining scheduling statistical information which comprises charge and discharge times and charge and discharge power of various types of electric vehicles and optimization information of the start and stop of a unit. Compared with the prior art, the method has the advantages of quickness and high reliability, high feasibility and a wide application range.

The invention provides a wheel set loading running-in test bench. A pit-type installation mode is used. The wheel set loading running-in test bench comprises a main body part 1, a walking board assembly 2, a safety sliding lift door assembly 3, an escalator assembly 4, a guardrail 5, a foundation assembly 6, an electric control system assembly 7, a hydraulic system assembly 8, a ventilation cooling device 9, a temperature detection system, a noise detection system, a vibration detection system, a camera monitoring system, a test report output printing system and a lighting device. The wheel set loading running-in test bench has an integrated detection function, can detect the operation rotation speed, can record time, can detect the bearing temperature, can detect the vibration of a gear box, can detect noise and can carry out video surveillance.

The invention discloses a self-adaptive precise recycling control method of a carrier rocket. A nonlinear model truly embodying the dynamic properties of the carrier rocket is adopted, a return phasedynamic model is built, and system parameter uncertainty and interference are introduced; in order to estimate the parameter uncertainty in the dynamic model of the carrier rocket repeatedly used andimprove the accuracy of estimation, a self-adaptive sliding-mode observer is built, and a self-adaptive estimation rule of the parameters (as shown in the description) is designed; based on a backstepping control thought, a tracking controller of a sliding-mode dynamic surface is designed. According to the method, unmodeled dynamics of pneumatic parameters and uncertain factors caused by the influence of fuel consumption are considered at the same time, so that the proposed model better conforms to the actual running condition of a sublevel control system of the carrier rocket in a vertical return phase; the designed self-adaptive parameter observer does not need the known condition of the upper bound of uncertainty and interference, and has more advantages in practical application; the accuracy of uncertain estimation is improved due to appropriate adjustment of time varying gain relative to interference.

The invention provides a control method and system of the switch-off process of a relay of a power battery. The control method comprises the following steps: after receiving a command of switching off the relay, judging whether the conditions of switching off an anode relay are satisfied or not according to the running states of a vehicle and a power battery system, and if yes, sending out a command of switching off the anode relay so as to switch off the anode relay; and after switching off the anode relay, judging whether conditions of switching off a cathode relay are satisfied or not according to the running states of the vehicle and the power battery system, and if yes, sending out a command of switching off the cathode relay so as to switch off the anode relay. Therefore, according to the control method disclosed by the invention, the running states of the vehicle and the power battery system are comprehensively considered, and the corresponding relay can be switched off only when the switch-off conditions are satisfied, wherein the switch-off conditions include the failure level, the interval time of states, and the constraint conditions of electric current and conform to the actual running states of the vehicle and the power battery system. Thus, the service life of the power battery system is prolonged, and the safe running of the vehicle is guaranteed.

The invention relates to a traffic safety risk field construction method based on WIM data. The method comprises the steps that the traffic flow law and traffic behavior of different axle vehicles areanalyzed based on measured WIM data, and a cellular automaton traffic simulation model considering load characteristics is constructed; potential collision energy is used as an indicator to measure risk consequences, and a traffic safety risk assessment indicator set is established; a traffic safety space-time dimension risk field model is established; and finally traffic safety risk level assessment based on the WIM data is realized. Compared with the prior art, the method provided by the invention considers the influence of load characteristics on traffic safety, realizes the visualizationof the space-time dimension of traffic risks, provides a new theory and a new method for traffic safety risk assessment and active safety control, and provides a theoretical basis and technical support for dynamic assessment and early warning of traffic safety risks of express ways, high-risk roads, and particularly bridges, tunnels and other key transportation infrastructures.

The invention discloses an automobile sideslip detector and a method for detecting sideslip. The automobile sideslip detector consists of a mechanical part and an electric part, wherein chain wheels of the mechanical part are fixed on a chain wheel shaft, and a plane link plate and two chain wheels form chain drive connection; a base plate is arranged on a sliding plate, the sliding plate is connected with a plate type linear guide rail through a ball bearing, and the sliding plate can reciprocate on the plate type guide rail transversely; a left-shift sensor and a right-shift sensor of the electric part are connected with an amplifier respectively, and the amplifier is connected with a microprocessor through an A/D converter; a rotary encoder is connected with the microprocessor through a counting circuit; and a rotating shaft of the rotary encoder and the chain wheel shaft are arranged coaxially, and the fixed parts of the left-shift sensor and the right-shift sensor are arranged on the plate type linear guide rail. The sideslip detector amplifies the detection running distance X of a detected automobile so that the detection is more accurate, and can measure sideslip values at different speeds and different loads for accurately matching suspension fork positional parameters of a front steering wheel.

The invention discloses an interval state estimation algorithm considering a power flow constraint for a power distribution network. The algorithm comprises the following steps of (1) establishing a state estimation method based on hybrid measurement data of SCADA and a PMU; (2) carrying out mathematical modeling on uncertainty of network parameters, distributed power generation, electric vehiclesand measurement data, and establishing an interval state estimation model; (3) taking a power flow equation of the network as a constraint condition of the interval state estimation algorithm, and establishing an interval state estimation model added with the power flow constraint; and (4) carrying out iteration solving by utilizing a Krawczyk operator in order to obtain a solution algorithm which is closer to an interval set of a solution set shell. According to the algorithm, the power flow equation is taken as the constraint condition of the interval state estimation algorithm, a problem that a part of the result exceeds the feasible solution interval is further relieved, the actual operation condition of the power distribution network is better met, the more rapid convergence speed can be obtained, the algorithm is quite suitable for engineering application, and the application prospect is good.

The invention relates to a method for simulating a power grid interlocking fault based on complicated network theoretical calculation and correction control, and belongs to the technical field of safety and reliability protection of power systems. The method comprises the following steps of utilizing a computer, and performing procedures; firstly, calculating the optimum trend of a power system under the normal condition; calculating the betweenness of each node, determining a betweenness threshold value of each node of the power system, simulating the interlocking fault of the power system, and finally calculating the total loss load of the interlocking fault. The method has the advantages that under the condition of meeting the safety running constraint requirement of the power system, the influence of correction control on the interlocking fault can be simulated by adjusting the output power and reduced load of a power generator, the influence of the change of load distribution on the interlocking fault can be reflected, and the propagation process of the interlocking fault of the power system can be well reflected; the method is widely applied to simulate the interlocking fault of the power system, is particularly suitable for simulating the interlocking fault of large complicated power systems, and can provide scientific basis for preventing the occurrence of the interlocking fault of the power system.

The invention discloses a frequency domain method for identifying rotor side controller parameters of a double-fed wind turbine generator. The frequency domain method includes: firstly, determining d-axis and q-axis decoupling models and the parameters to be identified on a rotor side controller; then injecting pseudo random signals to reference signals of the rotor side controller; calculating autopower spectrum of input signals and cross-power spectrum of the input signals and output signals according to the inputted pseudo random signals and outputted rotor current d-axis or q-axis weight which are acquired synchronously, and acquiring a frequency sequence of transfer function of the rotor side controller decoupling models; finally, identifying parameters on the rotor side controller on the basis of damping nonlinear least square optimization method. The experimental method is simple by identifying the rotor side controller parameters on the basis of the decoupling models; the pseudo random signals are superimposed on the inputted reference signals as excitement without affecting normal work of the double-fed wind turbine generator, and the experimental method is practical.

The invention provides a power distribution network information physical system reliability analysis method under a power distribution automation condition. The method comprises the following steps: S1, inputting power distribution network physical system element parameters and a topological connection relationship, and inputting power distribution network information system element parameters anda node adjacency matrix; S2, extracting the states of a current physical system and an information system by using a sequential Monte Carlo method; S3, calculating the fault isolation time of a current fault; S4, analyzing the influence of the current fault on load points; S5, updating the simulation time, judging whether a simulation ending condition is met or not, if so, executing the step S6,and otherwise, executing the step S2; S6, counting reliability indexes of each load point; and S7, calculating a reliability index of the whole power distribution network information physical system.The method can evaluate the influence of the distribution automation condition on the reliability of the power distribution network information physical system more accurately and more meticulously,and is more suitable for reliability evaluation and planning of a stock power distribution network and an intelligent power distribution network.

The invention discloses a power distribution system reliability assessment method considering a distributed power supply. The power distribution system reliability assessment method is characterized by comprising the following steps: S1, establishing an output power probability model of the distributed power supply; S2, establishing a load time-sequence dynamic model; S3, calculating the successful operation probability of an island based on the output power probability model of the distributed power supply and the load time-sequence dynamic model in the island; S4, for load points in the island, acquiring the reliability index of second-class load points according to the successful operation probability of the island and a minimum path method after improvement; and S5, acquiring the reliability index of first-class load points, acquiring system reliability index according to the reliability index of the first-class load points and the reliability index of the second-class load points, and carrying out assessment on power distribution system reliability according to the system reliability index. According to the power distribution system reliability assessment method, the actual power output level and load dynamic characteristics of the distributed power supply can be reflected, and the island operation manner of a power distribution system is sufficiently considered, so that the actual operation condition of a power grid is met, and the method is suitable for the power distribution system reliability assessment containing the distributed power supply.

The invention discloses a multi-energy park day-ahead economic dispatching method by considering demand response and containing electric vehicles. The method comprises the following steps: firstly, modeling each device in the park according to the determined specific composition of the multi-energy park; then introducing the electric vehicle while considering the demand response; taking the minimum total operating cost of the park as an objective function; considering related constraint conditions; combining a Monte Carlo scene theory; constructing a multi-energy park day-ahead economic dispatch random model by considering the uncertainty of wind power output and photovoltaic output, verifying the contribution advantages of demand response and electric vehicles to multi-energy park economic operation and new energy consumption, and obtaining a multi-energy park day-ahead economic dispatch strategy containing the electric vehicles and by considering the demand response. A demand response mechanism and an electric vehicle are introduced to further improve the new energy consumption capability of the park and enhance the operation economy of the multi-energy park.

The invention discloses a generation and transmission system operation reliability modeling and evaluation method considering primary and secondary frequency modulation. Firstly, in view of the problem that the existing system state analysis model does not consider primary frequency modulation of a wind turbine and secondary frequency modulation of an AGC unit, and after load shedding, the frequency is constantly kept at a lower limit, a load shedding optimization model considering a power flow model for primary frequency modulation of the wind turbine, the primary frequency modulation, the second frequency modulation and the minimum frequency deviation is provided; and on the basis, multiple uncertain factors such as the wind speed, the frequency modulation capacity of the wind turbine, the difference adjustment coefficient, element fault and load fluctuation are further considered, a generation and transmission system operation reliability evaluation method considering primary and secondary frequency modulation is provided, a frequency operation reliability evaluation index is built, and the possibility and the severity of frequency exceeding limit are reflected comprehensively; and finally, on an MATLAB platform, calculation and analysis on the generation and transmission system operation reliability evaluation considering primary and secondary frequency modulation are realized through a program.