Assessment method considering voltage probabilities of multiple electric power systems with wind power output randomness

Abstract

The invention discloses an assessment method considering voltage probabilities of multiple electric power systems with wind power output randomness. The assessment method comprises the following steps: determining a weight coefficient, a mean vector and a covariance coefficient matrix according to a wind power predicted value matrix and a wind power actual value sample matrix of a plurality of wind power plants; calculating first-order and second-order sensitivity vector matrixes from node voltages to the wind power predicted value matrix; determining cumulative distribution functions of the node voltage corresponding to each Gaussian component according to the first-order and second-order sensitivity vector matrixes, the mean vector and the covariance coefficient matrix; determining cumulative distribution functions of the node voltage corresponding to a Gaussian hybrid model according to each cumulative distribution function and the weight coefficient. According to the assessment method, the cumulative distribution functions of the node voltages can be determined through extracting the wind power predicted value matrix and the wind power actual value sample matrix of the plurality of wind power plants, so that the used time is short; the first-order and second-order sensitivity vector matrixes are calculated, so that the nonlinear relationship between the node voltages and the wind power is fully considered and the correctness is high.

Description

technical field [0001] The invention relates to the technical field of wind farm power systems, in particular to a method for evaluating the voltage probability of a power system considering the randomness of multiple wind power outputs. Background technique [0002] In the power system, wind power output is random, and it is impossible to accurately evaluate the CDF (Cumulative distribution function, cumulative distribution function of random variables) and PDF (Probabilistic density distribution, probability density function of random variables) of the node voltage of the power system. [0003] In order to obtain the CDF and PDF of the node voltage, there are currently two main methods: linearization method and Monte Carlo simulation. in, [0004] The linearization method mainly writes the output variable (node ​​voltage) approximately as a linear function of the input variable (wind power), and then calculates the CDF and PDF of the node voltage according to some probabi...

AI Technical Summary

Problems solved by technology

However, the disadvantage of the Monte Carlo simulation method is that a large number of sampling points are required to generate sample points, and power flow calculations are performed at these sample points, and the calculation time is long

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