A probabilistic power flow calculation method for hybrid power grid considering high-dimensional random variables with correlation

Abstract

The invention discloses a method for calculating the probability power flow of a hybrid power grid considering high-dimensional random variables with correlation, including determining the probability distribution type and parameters of the random variable in the hybrid power grid according to the historical data, and calculating the probability distribution between the random variables The correlation matrix R X ; Transform the random variable that obeys any distribution into the standard Gaussian distribution domain, and the correlation matrix R between the random variables X Calculate the correlation matrix R between the standard Gaussian distributions Z ; Based on the correlation matrix R Z , to calculate the covariance matrix P between standard Gaussian distributions ZZ ;Determine the scale expansion coefficient α of the STUT algorithm when dealing with random variables that obey the standard Gaussian distribution; select the sample point Z on the standard Gaussian distribution domain; inversely transform the sample point Z to the multi-dimensional arbitrary distribution domain; convert the multi-dimensional arbitrary distribution domain 2n+1 groups of sample points are used as input to perform deterministic power flow calculation of hybrid power grid group by group. Improve the reliability and security of grid operation.

Description

technical field [0001] The embodiments of the present invention relate to the technical field of grid-connected new energy sources, and in particular to a method for calculating a probabilistic power flow of a hybrid power grid considering high-dimensional random variables with correlations. Background technique [0002] The Voltage Source Converter based High Voltage Direct Current (VSC-HVDC) system will be widely used in new energy base grid connection, asynchronous grid interconnection and regional transmission grid strengthening. A large number of probabilistic uncertainty sources will emerge in the future AC / VSC-MTDC hybrid grid. At the same time, there is often a certain degree of correlation among these sources of uncertainty. Then, the probabilistic power flow calculation of AC / VSC-MTDC hybrid grid can be defined as a high-dimensional probabilistic power flow analysis problem with correlation. [0003] The probabilistic power flow calculation methods can generally ...

AI Technical Summary

Problems solved by technology

However, when the TUT algorithm deals with high-dimensional uncertainty analysis problems, its sample points will have a "sample point discrete effect" with the increase of the dimension of the random variable, which will eventually lead to a decrease in the accuracy of the probabilistic power flow analysis

Images