109 results about "Stability constraints" patented technology

A method and system may determine, in a vehicle, a desired path around an object based on a location of the object relative to the vehicle, relative speed, road parameters and one or more vehicle parameters. The method and system may calculate one or more vehicle control parameter values which minimize a predicted deviation from the desired vehicle path. The method and system may determine whether the one or more vehicle control parameter values would cause the vehicle to exceed one or more vehicle stability constraints. If the one or more vehicle control parameter values would cause the vehicle to exceed one or more vehicle stability constraints, the one or more vehicle control parameter values may be reduced to one or more vehicle control parameter values not causing the vehicle to exceed the one or more vehicle stability constraints. The method and system may output the one or more vehicle control parameter values to a vehicle automated control device.

The present invention relates to a power system and provides a method for considering the network security constraints of in the operation of economic dispatch of power systems, which comprises the power flow constraint of branches, the static voltage stability constraint and the transient stability constraint, and provides an effective way for coordinating contradiction between the economy and security of power system operation. The security region based security-constrained economic dispatching method comprises the following steps: step 1, calculating the coefficients for the active power static security region, the cut-set voltage stability region and the dynamic security region respectively; step 2: building the models for security region based security-constrained economic dispatch; step 3: solving the unit on/off state optimal sub-problem through Social Evolutionary Programming; step 4: calculating the generation cost, the static voltage stability margin and the transient stability margin in the dispatching period; step 5: obtaining a feasible economic dispatching scheme, otherwise, return to step 3. The invention is mainly applied in load dispatching optimization.

A system and method for separating a mixture of audio signal into desired audio signals (430) (e.g., speech) and a noise sign (440) is disclosed. Microphones (310, 320) are positioned to receive the mixed audio signals, and an independent component analysis (ICA) processes (212) the sound mixture using stability constraints. The ICA process (508) uses predefined characteristics of the desired speech signal to identify and isolate a target sound signal (430). Filter coefficients are adapted with a learning rule and filter weight update dynamics are stabilized to assist convergence to a stable separated ICA signal result. The separated signals may be peripherally-processed to further reduce noise effects using post-processing (214) and pre-processing (220, 230) techniques and information. The proposed system is designed and easily adaptable for implementation on DSP units or CPUs in audio communication hardware environments.

The invention discloses a micro-grid system voltage stability control method based on robust control. The control structure of an intelligent micro-grid system is composed of a system control layer, a concentrated control layer and a local control layer, and energy optimization and voltage and frequency stability control of the micro-grid system are realized through multi-layer coordination control. According to the micro-grid system voltage stability control method based on robust control, a comprehensive load module of an induction motor is established, wherein dynamic loads are connected with static loads in parallel. On the premise that the constraint conditions of system performance and robust stability are met, a micro-grid voltage stability robust controller is designed by the adoption of a method of solving the problem of mixed sensitivity so as to improve the micro-grid voltage stability. The micro-grid system voltage stability control method based on robust control can be adapted to wide-range change of load parameters, has high robustness for the situations that due to the factors such as changes of running conditions, influences of external environment and frequency switching of the loads, perturbation is generated in model parameters of a micro-grid and uncertainty exists in the topologic part and the unmolded part and can better restrain parameter drift and noise interference, and meanwhile, the controller is simple in structure and easy to realize.

A system for accurately determining real-time Available Transfer Capability and the required ancillary service of large-scale interconnected power systems in an open-access transmission environment, subject to static and dynamic security constraints of a list of credible contingencies, including line thermal limits, bus voltage limits, voltage stability (steady-state stability) constraints, and transient stability constraints.

The invention discloses a method for calculating the optimal admitting ability for wind power multipoint access of a regional power grid and belongs to the technical field of wind power penetration methods of the power grid. The method for calculating the optimal admitting ability for the wind power multipoint access of the regional power grid comprises the steps that the installed capacity of all wind power plants is initialized, and data such as the local wind speed are acquired; the output condition of all the wind power plants is calculated, and unit commitment and optimization within all dispatching cycles are conducted, so that an annual unit commitment mode of an electric power system comprising the wind power plants is obtained; power flow calculation is conducted based on each period of time, whether an operation constraint condition of the system is met is verified, and a final objective function value is calculated after simulation is conducted on the system for more than 8760 hours; the installed capacity of the wind power plants is updated, optimized iteration is conducted on an objective function, and optimal solution of the wind power generating capacity is achieved, namely the optimal admitting ability of the power grid which enables the economical efficiency of the system to be optimized on the premise that the safety and stability constraint conditions are met is achieved. According to the method for calculating the optimal admitting ability for the wind power multipoint access of the regional power grid, an optimal wind power admitting capacity calculation model with the largest net earning of a wind power plant and power grid combination system (with the environmental benefit considered) as the purpose is established, and suggestions can be provided for the proper establishment of the installed capacity of the regional wind power plants.

The invention relates to a method of toolpath generation and cutting parameters optimization for high speed milling of a convex pocket, wherein said method comprises a first sub-method of generating a toolpath and a second sub-method of generating optimized chatfree cutting parameters using a genetic algorithm wherein the first sub-method generates milling toolpaths that minimize the radial depth of cut variations as well as the curvature change variations while avoiding leftover material at the corners, wherein said toolpaths automatically avoid self-intersecting features encountered during the offsetting of pocket boundary such that the said toolpaths result in reduction in milling time for a given maximum acceptable radial depth of cut and wherein said second sub-method allows the free choice of cutting parameters and optimizes the milling time and wherein the optimization method incorporates relevant milling constraints as milling stability constraint, cutting forces, machine-tool and cutting tool capabilities.

The invention discloses a new energy available capability assessment method considering transient security constraints, belongs to the field of new energy available capability assessment. According to the invention, on the basis of the EEAC theory, transient security constraints are added into an existing new energy available capability assessment method; and on the basis of the existing assessment method with peak and frequency modulation constraints as reference, full consideration is given to the transient security stability constraints of an outgoing channel, the transient power angle stability margin, transient voltage security margin and transient frequency drop acceptability margin are quantified, and the unit adjustment sequence is determined according to the magnitude of sensitivity of the output adjustment of a new energy unit under a buckling mode. The invention is capable of achieving optimal output adjustment of the new energy unit under a transient buckling forbidden faulty set, and meanwhile achieving the new energy grid-connected maximum availability while satisfying safe and stable operation of a power grid.

The invention discloses an addressing and capacity configuration method used for a UPFC. A UPFC addressing and capacity configuration model with transient stability constraints is established, a difference evolution algorithm serves as a framework, and the installation position and the capacity of the UPFC are optimized; in addition, a centrality correction interior point method is adopted for carrying out optimization and fitness assessment on continuous variables of each difference evolution unit. The difference evolution algorithm is simple in operation, high in searching capability, fewer in adjusting parameters and suitable for mixed optimization, and the interior point method is good in convergence and strong in robustness, so that the provided mixed algorithm can well solve the problems of UPFC addressing and capacity configuration, the method is highly efficient and convenient, and the application prospect is good.

The invention belongs to the technical field of logistics, and discloses a dynamic optimization box stacking method and an information data processing terminal. The method comprises the steps that a tray is divided in space, and a gap information table is initialized; box information is placed into a dynamic box queue according to the sequence, and a gap information table Gap-Table is built/updated; an available gap for placing a box is searched for; according to the box size, the Gap-Table is searched for all gaps capable of containing the box, and the gaps are stored into the Gap-Table; thegaps in the Gap-Table are subjected to priority ordering, and a prior sequence is given; box placing positions are subjected to heuristic dynamic programming; and the tray is replaced. In the achieving process, box number and size information incomplete restraint, stacking sequence restraint and stability restraint are ensured, complete supporting is adopted, and therefore it is ensured that wholestacking is kept stable and free of collapsing. The method can adapt to a practical stacking site and ensures the good tray space utilization rate.

The invention belongs to the power system calculating and analysis technology field, and is applicable to calculate limit powers of associated electricity transmission cross-sections considering static, transient and dynamic security and stability constraints. The limit power calculating method of associated electricity transmission cross-section based on parallel calculating model comprises the steps of firstly calculating a static security limit, and then calculating security and stability limits of the transient and dynamic, on the basis of estimating the power increasing amount of each cross-sections considering over loading security of equipment; classifying the power increasing space of each cross-sections in turn according to the examined failure number and the example calculating capability of a parallel processing platform, and carrying out security and stability calculations for the run modes of different electricity transmission power combinations of each cross-sections by parallel example; judging whether to carry out security and stability calculations of the next round according to the precision requirement of limit calculation after all examples of the round being calculated, and filtering the examined failure set before each round of calculation; and finally, calculating mutual influence factors between limit powers of each cross-sections by analyzing the limitcalculation process information.

The invention provides an agile satellite task planning and scheduling modeling method based on genetic optimization, which comprises the following steps of: dynamically decomposing a to-be-observed complex observation target task area according to an observation demand of a user and a resource condition of a satellite, and generating a meta-task set with a plurality of time windows; constructinga constraint analysis model according to the task constraint, the resource constraint and the relationship between the task constraint and the resource constraint, wherein the constraint analysis model comprises a satellite energy constraint model, a storage constraint model, a minimum pitch angle constraint model and an attitude maneuver stability constraint model; establishing a single-satellitetask planning mathematical model according to the multi-time window element task set; and utilizing a genetic search algorithm to optimize and solve the single-satellite task planning mathematical model, judging whether the established constraint analysis model is met or not, and generating a final executable observation plan scheme. According to the method, the task observation plan scheme meeting the maximum objective function and different constraint analysis can be generated, satellite resources are effectively utilized, and the task planning efficiency is improved.

The invention relates to a method for constructing a motion space for a robot under inherent constraints. The method is characterized in that the method includes: (Step S1) with supporting legs as an origin of coordinates, floating body kinematics is introduced into a body base coordinate system to create a joint chain and kinematic model based on the joints of the whole body; (Step S2) on the basis of the joint chain and kinematic model, a joint angle range constraint and a stability constraint are introduced, and the Monte Carlo method is utilized to sample and solve a working space for the end actuators of the robot, so that a three-dimensional point cloud grid formed by the working space is obtained; (Step S3) on the basis of the three-dimensional point cloud grid, plane cutting is carried out, and by means of extreme value analysis, the extreme value state and position and posture diagram of the robot in each direction are obtained. In comparison with the prior art, with the solution of the working space of the robot under the complex motion of the whole body as a goal, the method obtains the boundary range of the working space of end tracks under a complex condition meeting inherent constraints on the basis of the numerical algorithm.

The invention provides a unit speed regulation system control parameter setting method considering frequency modulation and stability constraints. The method comprises the following steps: S1) carrying out analysis on stability of a possible isolated-network-operation hydropower unit speed regulation control system; S2) obtaining a range of control parameters with primary frequency modulation performance constraint of a unit being taken into consideration; S3) under the premise of meeting small disturbance stability, giving a range of control parameters of the unit speed regulation system; S4) obtaining unit prime motor and speed regulation system measured parameters through actual measurement modeling, and obtaining overlap based on the ranges of the control parameters and applying the data to simulation analysis verification instances of the setting method; and S5) for a primary frequency modulation parameter setting range and a small interference stability parameter stability range, carrying out overall consideration, and finally, obtaining a parameter value range capable of meeting both frequency modulation performance requirements and small interference stability requirements, and carrying out setting on the unit speed regulation system model parameters. The method can obtain parameter values meeting both requirements under the premise of meeting double-term index requirements.

The invention relates to an emergency dispatching method of increasing the power grid transmission capacity, belonging to the electric power system dispatching automation field. Firstly, an extremity transfer capacity of a main transmission section of a power grid is scanned online, so as to gain a transmission margin; secondly, a load increment of future time is calculated via ultra-short term load forecasting to determine a total power generation adjustment quantity of the power grid of the future time; then, an output adjustment quantity of a generator of next period according to the number of the transmission section whose the transmission margin is less than a setting value and the difference of the kinds of restrictive factors of each transmission section, when the power grid is provided with: the transmission margin of one transmission section is less than the setting value and is a static security constraint; the transmission margins of a plurality of transmission sections are less than the setting value and are the static security constraint; the transmission margin of one transmission section is less than the setting value and is a transient stability constraint. The method of the invention can improve the transmission capacity of the transmission section when the transmission margin of the main transmission section of the power grid is insufficient, so as to reduce or avoid the phenomenon of the restriction of electricity.

The invention discloses a transient stability constraint optimal power flow computation method based on an EEAC and trace sensitivity, and belongs to the technical field of power system transient analysis. The method comprises the steps that a conventional optimal power flow solution is adopted as an initial operating point to calculate a transient initial value, and an anticipated fault set is set; transient time-domain simulation and EEAC equivalent operation are carried out on all faults in the anticipated fault set, the faults are classified, and the faults meeting the fault stability margin requirement are removed out of the anticipated fault set; the trace sensitivity of the faults not meeting the fault stability margin requirement is calculated, the margin sensitivity of the faults under different types is given, and a transient stability constraint is constructed according to the margin sensitivity of the faults; after the transient stability constraint is embedded in conventional optimal power flow model, an optimal power flow model including the simple transient stability constraint is obtained, the situation that transient stability cannot be quantized when only power angles are adopted as transient stability criterions is avoided, computation complexity is reduced, and the problem of difficult convergence is solved.

The invention discloses a method for evaluating the new energy acceptance capacity of a grid-connected point by comprehensively considering the stability characteristic, and belongs to the technical field of automation of power systems. The influences of wind power generation variability and instability on a power grid, an external load level and the change condition thereof are combined; a multi-machine system is equivalent to a single-machine infinite bus system through an EEAC method by employing a static stability constraint, reactive power control and a transient constraint of the power system as conditions; the stability margin and the sampling yield are calculated; and the capability of connecting a wind power station of considering a transient stability constraint to the power grid to the maximum extent is evaluated by employing the specified range of the sampling yield as an index. By the method, the safe and stable operation level of the wind power station can be improved; the generating capacity of the wind power station is effectively ensured; and the benefits of energy conservation and emission reduction are improved.

A method for controlling and monitoring a hybrid vehicle including a driving internal combustion engine, and an electric machine that is operational, upon an instruction, in a form of a driving engine and is powered by a battery. The method detects a vehicle operating state, in transmitting, in response, an operating instruction to the electric machine only, without requesting any particular instruction from the internal combustion engine and respecting the vehicle stability constraint and a protecting constraint of the electric components thereof.

The invention discloses a distributed electric drive vehicle multi-performance optimization torque distribution method. A MPC controller based on an improved C/GMRES algorithm is adopted to conduct multi-performance optimization torque distribution. The multi-performance optimization torque distribution method comprises the steps that a longitudinal total driving torque and a yawing torque given by an upper controller are used as the torque distribution control input by the MPC controller, tire related information fed back from the vehicle is combined, a model is updated based on the wheel rotation dynamics and the tire slip rate state, the physical characteristics of the output torque of a hub motor are considered, the wheel load rate is taken as the stability constraint precondition, minimizing of the tire slip dissipation energy is taken as the optimization objective, the MPC optimal control problem is established, the improved C/GMRES algorithm is adopted to solve the problem of the torque optimization distribution quickly, and thus the real-time optimal control of vehicle stability and economy is achieved. According to the distributed electric drive vehicle multi-performance optimization torque distribution method, the MPC controller based on the improved C/GMRES algorithm is adopted to conduct multi-performance optimization torque distribution, the tire slip dissipation energy is minimized on the precondition of ensuring the vehicle stability, and the algorithm has high computational efficiency and is suitable for real-time application.

The invention discloses an online emergency control decision-making method considering transient state and static state security and stability constraint, and belongs to the security and stability emergency control technical field of the electric power system. For overcoming the problems that multiple kinds of problems exiting in the security and stability of the large power grid are mingled, and the online decision-making time is short, different types of control measures are chosen specific to different kinds of problems exiting in security and stability; the control measures of each type are screened based on the control performance indexes separately; the screened measures of different controllable equipment are enumerated and combined; the enumerated and combined measures are screened through the power sensitivity based overload security verification and power frequency characteristic based transient state frequency security verification; and finally, the screened enumerated and combined measures are subjected to transient state and static state security and stability quantitative evaluation by adopting a cluster computing mode. The calculation strategies are classified and sequenced specific to the problems exiting in security and stability, so that the rapid and optimized decision making of the online emergency control considering the transient state and static state security and stability constraint is realized.

The invention provides a power system transient stability multi-fault constraint preventing control method. According to the method, a buckling failure is decoupled through expected fault position topology analysis; a multi-fault adjusting timing sequence is set according to fault severity, and a multi-fault constraint preventing control problem is reduced in a dimensional aspect into a multiple single fault stability control decision problem; finally, a preventing control adjusting strategy capable of meeting requirements of all transient stability constraints is obtained. According to the method, in the adjusting process, the economic type of prevention control is considered, a corresponding adjusting gear is distributed for the power adjusting space of each fault, and a strategy, smallest in adjustment, meeting the requirements of operation modes of multiple fault constraints is confirmed through a parallel calculating mode.

The invention discloses a multi-user multi-task mobile edge computing energy-saving method based on heterogeneous energy acquisition. The method comprises the following steps: firstly constructing a problem of minimizing the average energy consumption under the guarantee of time delay on the premise of meeting the stability constraint of a data queue and the stability constraint of an energy queue; in order to solve the random optimization problem, the problem is converted into two deterministic sub-problems, and a convex optimization technology and a linear programming technology are respectively adopted to solve the two deterministic sub-problems. The method does not need priori knowledge of a random process, such as channel state, data arrival and green energy collection. And energy consumption-time delay balance of [O (1/V), O (V)] is realized. And V is used as a non-negative weight, so that the energy consumption-time delay performance can be effectively controlled.

The invention discloses a design method of dual compensators of a dual-way feedforward disturbance observer. A system stability control platform has insufficient low frequency and medium frequency disturbance suppression capability, thereby failing to meet higher precision demand of system stability control. Design of the traditional disturbance observer is improved based on multi-closed loop control, so as to provide a design method of dual compensators of a dual-way feedforward disturbance observer. Design of the dual-compensator is based on system stability at first, and then design of disturbance suppression based on different frequencies is conducted, wherein an inner loop disturbs a feedforward loop to suppress low frequency disturbance, and an outer loop disturbs the feedforward loop to suppress medium frequency disturbance, and the dual compensators act simultaneously so as to improve low frequency and medium frequency disturbance suppression capabilities of the system, therefore, the system stability is ensured, and system stability control accuracy is improved effectively.