43 results about "Wind power penetration" patented technology

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.

A wind power penetration limit calculating method that considers frequency constraint and wind power frequency modulation; the method comprises the following steps: using a weight equivalence polymerization method to solve a wind power plant primary frequency modulation response transfer function model and a wind power primary frequency modulation active increment; considering a wind power virtualinertia control strategy, and solving a power system equivalent inertia time constant under different wind power penetration rates; calculating a load damping effect, building a power grid frequencyresponse model that is equivalent to a rotor swing equation, and using the model to describe power system frequency response characteristics; using the power system frequency stable state deviation boundary and frequency rate of change boundary as constraints, and proposing the power grid wind power penetration limit calculating method. The method introduces the real wind power virtual inertia response, the active increment formed by the primary frequency modulation response and the power system frequency constraint into the wind power penetration limit calculation, thus improving the power grid robustness under the wind power grid connection condition, ensuring the power grid to stable and safely operate, and providing important guiding meanings for wind power grid connection planning construction.

The invention discloses a control method of active power of clustered wind power plants, which is used for calculating a planned value of active power distributed to each wind power plant, issued by a provincial (municipal) level scheduling mechanism. The method for calculating the distributed active power provided by the invention can determine the active power planned value of each clustered wind power plant in the next control period, and the total capacity of wind power penetration into a power grid is calculated in real time, so that the power of each clustered wind power plant is maximized under the premise that an electrical power system operates safely and stably is guaranteed. According to the invention, many-sided factors such as the change of the total capacity of wind power penetration into the power grid, the current power of each wind power plant, wind power forecast conditions and load forecasting conditions, the planned value of each wind power plant is calculated in the fixed period and is sent to each wind power plant, the planned value is an upper limit value, the wind power plant can freely generate electricity when the current value is below the planned value, and an application is needed when the current value is above the planned value. According to the invention, the generating efficiency of the wind power plants is improved furthest, and wind power penetration into the power grid system is maximized.

The invention discloses a dynamic primary thermal power generating unit frequency modulation control method for a power grid with the high wind power penetration rate, and relates to a dynamic primary thermal power generating unit frequency modulation control method. In order to reduce influences caused by wind power output power fluctuation on system frequency stabilization, the primary frequency modulation control method for dynamically adjusting a difference adjustment coefficient of a thermal power generating unit is proposed by analyzing the frequency response characteristics of the thermal power generating unit when primary frequency modulation is conducted on the thermal power generating unit on the premise that the stability of the thermal power generating unit is guaranteed. According to the control method, the primary frequency modulation capability of the thermal power generating unit can be effectively improved, the thermal power generating unit can achieve the higher flexibility and capability when primary frequency modulation is conducted on the thermal power generating unit, and therefore frequency stabilization of a wind power-containing system is promoted. In a wind power-containing single-area simulation system, when 15% of wind power prediction errors are taken into account, the maximum fluctuation deviation of the system frequency is decreased to 0.0663 Hz from 0.126 Hz, and therefore the requirement of the power grid on the frequency is met. The control method is applied in the field of thermal power generating unit control.

The present invention discloses a wind power penetration power limit analysis method based on a stochastic optimal power flow. The method comprises the following steps: establishing a wind power penetration power limit calculation model based on a probabilistic optimal power flow, and setting system information and particle swarm algorithm initial parameter(s); generating control variable initialvalue(s) and particle initial speed(s) randomly; generating wind farm wind speed sample(s) randomly, calculating system power flow(s) of particles under all sample(s), and judging the fact that whether chance constraint(s) are met; adding the chance constraint(s) into a fitness function, calculating fitness value(s) of all particles, obtaining an individual optimal value and a global optimal value, and updating the speed(s) and position(s) of all particles; and judging the fact that whether a maximum iteration number is met, if the maximum iteration number is not met, regenerating the wind farm wind speed sample(s) randomly and calculating, and if the maximum iteration number is met, outputting optimal decision variable(s) and a wind power penetration power limit value. The method can satisfy wind power randomness and power flow equality constraint(s), and thus the wind power integration capability can be calculated directly.

The invention relates to the technical field of new energy grid connection, particularly to an energy storage system configuration method considering power grid frequency support requirements. The method is characterized by mainly comprising two parts of system maximum power increment solving and energy storage configuration, and comprises the following steps of: solving a maximum power incrementcapable of being borne by a system by taking a frequency change rate and a frequency deviation as limiting conditions; determining the output power and capacity of the energy storage system accordingto the maximum power increment; and finally carrying out virtual inertia configuration on the basis that the energy storage system grid-connected inverter adopts a three-order active support control strategy. According to the invention, the configuration method can flexibly govern the power flow discharge of the energy storage system, and effectively solves the problem of lack of inertia support and frequency modulation capability in the synchronous power grid under high wind power penetration.

The invention belongs to the field of dispatch of a power grid with wind power, and particularly relates to a wind power penetration limit calculation method in consideration of demand side response. The ability of absorbing the wind power by the power grid is enhanced through simultaneous control on source and load sides. The method mainly comprises steps: an active power output model for the wind power is built; a demand side response model is built; ideas of the economics and a node admittance matrix are used for building an electricity price sensitivity concept; a wind power generation limit penetration power expression is determined; and necessary constraints in an event are added in the case of calculation for simulation calculation. The result shows that by adopting the method of the invention, the wind power integration rate can be improved, and a greater wind power capacity can be integrated.

The invention provides a wind power frequency modulation control method suitable for a high wind power penetration level, and relates to the field of wind power generation grid connection, and the method comprises the following steps: monitoring the frequency of a power grid in real time, calculating the instantaneous frequency of the power grid, and when the frequency deviation of the power grid exceeds a set dead zone range due to the disturbance of a power system, measuring the rotating speed of a fan, and when the rotating speed omega r of a fan rotor is larger than the allowable minimum rotating speed omega min, starting a virtual inertia control module of the doubly-fed wind turbine generator, wherein the fan actively participates in frequency modulation; calculating the active increment of the wind turbine generator; calculating the equivalent active power increment of the time domain; calculating an active reference value of the fan; and after the time delta t, gently switching the active power output of the fan to the maximum power tracking output power, so the rotating speed gradually recovers to the initial state. A virtual inertia control link is additionally added to a wind turbine generator rotor side converter controller, when the power grid frequency exceeds the limit due to disturbance, the virtual inertia control link participates in frequency modulation of a power system by use of the rapid throughput of kinetic power of the fan rotor, the frequency modulation response is faster, and the effect is better.

The invention belongs to the technical field of modeling of daily net active powers of high wind power penetration busbars, and relates to a novel modeling method of considering that the net active power of each busbar has dual uncertainty characteristics of randomness and fuzziness. The method comprises the following steps: selecting daily net active power data of the busbars in a specific region over the years, fitting the probability distribution of the net active power data within each time period divided according to the requirements when the confidence ratio is 0.05 by a MATLAB probability density curve, and determining a confidence interval and a membership function model of the parameter fluctuation range; defining the net active powers as random fuzzy variables, obtaining an opportunity measurement function of the net active powers and building a random fuzzy uncertainty model; and finally providing the process and step of simulation generation of simulated daily net active powers of the busbars through a random fuzzy simulation technology and an inverse transform method. The novel modeling method can relatively comprehensively describe multiple uncertainty characteristics of the daily net active powers of the high wind power penetration busbars, and provides a corresponding guiding basis for electricity generation scheduling and dispatching of a high wind power-integrated power system in the future.

The invention provides a method for considering the influence of wind power and load characteristics on a power system. The method comprises the steps of establishes a VSC-HVDC AC/DC system model thatconsiders the wind power and load characteristics, an AC and DC continuous power flow model that considers the wind power and load characteristics, and a voltage stability risk indicator, calculatingrisk indicators in different scenarios by using an improved Monte Carlo simulation method to obtain weak points of the system, and analyzing voltage stability risks under different wind power penetration rates and VSC control methods. According to the method, the influence of wind power randomness and load characteristics on system voltage stability are fully considered, the risk indicators whichintegrate voltage changes and load margin changes are proposed, a weak area of the system is determined by using the indicators, the voltage risk values in different scenarios are evaluated by changing wind power permeability and DC control parameters, the accuracy of an AC system AC and DC voltage stability risk assessment result is greatly improved, and a reference can be provided for guiding the stable operation of the system.

The invention discloses a wind power penetration limit determination method based on peak-regulating balance constraint. The method comprises: firstly, solving wind power penetration limit of each selected time-in-point in a time interval [ton, toff], on each time-in-point, using a discrete variable search algorithm to perform maximum search on UGt, searching a generator set state vector UGt in a generator set state space [omega], the generator set state vector UGt making wind power capacity an electric system can accept reach the maximum in the time-in-point, and through a wind power penetration limit model to calculate the wind power penetration limit value at the moment; and performing minimum search on the wind power penetration limit values obtained in all time-in-points, to obtain the minimum value of wind power penetration limit in the interval of [ton, toff]. The method uses time combining with the generator set as decision variables, and an improved bender's decoupling algorithm is used for solution and optimization, preventing influence on calculation precision by selection of operating methods of an electric system and setting of original values. The method can improve precision and efficiency of wind power penetration limit calculation.

The invention discloses a quantitative calculation method for power grid inertia weakening in wind power plant grid connection, and the method comprises the steps: solving a day-ahead equivalent inertia mean value of a whole power grid, carrying out the clustering division to replace a wind power plant adjacent small-region power grid of the whole power grid, and taking the result as a wind powerplant inertia weakening amount solving object; solving the equivalent inertia of a small-area power grid by using an equivalent electromechanical transient swing equation; decomposing and extracting the online capacity of the rotating load by utilizing the total load real-time data of each substation gateway in the small-area power grid; according to the equivalent inertia of the small-area powergrid, the online capacity of the load and the scheduling information of the synchronous generator and the wind power plant, solving the inertia of the rotating load, solving the inertia time constantof the wind power plant in a grid-connected state and an off-grid state, and further calculating the inertia weakening amount. The method can provide an application basis for making a virtual inertiacontrol strategy of the wind power plant, determining the limit of the wind power penetration power of the power grid and the like.

The invention provides a method and a system for calculating dynamic wind power penetration power limit, and relates to the technical field of security defense and restoration control of a power system. The method comprises the following steps of expressing the transient security constraints of the power system in a binary table way, so as to obtain a binary table of transient security constraints, wherein the binary table comprises threshold values and time limits; acquiring the predicted wind power output data, and obtaining the most adverse wind power output scene according to the predictedwind power output data; under the most adverse wind power output scene, calculating the dynamic wind power penetration power limit of the power system according to the vector of number of wind poweraccessing sets and the binary table of transient security constraints; fully considering the change of the restoration scene of the large-power failure system, and accounting the transient security constraints of the system, so as to determine the reliable wind power accessing capacity, thereby enabling the wind power to safely participate in system restoration.

The invention discloses a wind power plant access capability analysis method based on a convergence effect. The method comprises the following steps: firstly, constructing a wind power plant penetration power limit calculation model, setting basic information and initial parameters of a power grid system, and randomly generating a control variable initial value and a particle initial speed; secondly, generating initial wind speed sample data by adopting a MonteCarlo simulation method for the output power of the wind power plant group based on a Copula theory, and sorting wind speed samples; then calculating the system power flow of the particles under each wind speed sample; adding opportunity constraints into a fitness function, calculating fitness values of all particles, obtaining an individual optimal value and a global optimal value, and updating speeds and positions of all the particles; and then judging whether the maximum number of iterations is satisfied, if not, returning torecalculate the system power flow of the particles under each wind speed sample, and if so, outputting an optimal decision variable and a wind power penetration limit value. According to the invention, the grid-connected capability of the wind power plant of each access point under the condition of considering the convergence effect of the wind power plant can be effectively calculated.

The invention provides a wind power base output distribution method considering reactive compensation switching voltage constraint. The wind power base output distribution method considering the reactive compensation switching voltage constraint comprises the following steps that a full-output operation mode of a window power base is established and is used as the fundamental mode; the voltage fluctuation delta V[ij], caused by switching single-unit reactive compensation of the jth wind power plant, of the ith bus is calculated in a simulating mode in the fundamental mode, wherein the initial value of j is 1, and the initial value of i is 1; whether delta V[ij] exceeds a threshold or not is judged; if yes, the wind power plant which is the most sensitive to the voltage fluctuation in the fundamental mode is determined, and control measures for lowering the output of the wind power plant are taken; if not, judgment of the influence of the switching single-unit reactive compensation of each wind power plant on the threshold exceeding of voltage fluctuation of each bus in the wind power base is completed. By the adoption of the wind power base output distribution method, the wind power plant which is influenced most by the reactive compensation switching is found through sensitivity calculation, the distribution mode, meeting the requirement of the reactive compensation voltage constraint, for the largest wind power output of the wind power base can be provided, the constraint that a power grid operates safely is met and the wind power penetration is improved.