Distribution network state estimation method based on event-triggered transmission mechanism and hybrid measurement

Abstract

The invention discloses a power distribution network state estimation method based on an event trigger transmission mechanism and hybrid measurement. The method comprises the steps of firstly obtaining the measurement in a power distribution network, then referring to the prediction feedback returned by a recursion filter, screening the measurement through the event trigger transmission mechanism,and transmitting the data meeting a trigger condition to an estimation center; after the estimation center obtains the data, carrying out filtering estimation under the conditions of simplifying hybrid measurement and considering non-triggering errors; when the filtering gain is solved, converting high-order nonlinear voltage amplitude measurement into an error-bounded quadratic nonlinear form, and designing an uncertainty term linear transformation method of a second-order nonlinear function ; solving a filtering gain when the upper bound of the covariance of the filtering error is minimum;and finally, estimating the state of the power distribution network. According to the method provided by the invention, the calculation process is greatly simplified and the calculation time is shortened on the premise of ensuring the estimation performance.

Description

technical field [0001] The invention relates to a distribution network state estimation method based on event-triggered transmission mechanism and mixed measurement. Background technique [0002] Due to the widespread connection of distributed energy sources and flexible loads, the distribution network is undergoing a fundamental change towards a more dynamic and complex structure. Therefore, in order to reliably monitor, control and protect the distribution network system, it is necessary to obtain accurate state information in real time, which puts forward higher requirements for the dynamic state estimation of the distribution network. [0003] In addition, with the rapid development of measurement and communication technologies in power systems, synchrophasor measurement unit systems (Phasor Measurement Units, PMUs) have gradually been applied to power systems to meet the requirements for accurate monitoring of system status. And a large amount of data generated by PMUs...

AI Technical Summary

Problems solved by technology

However, the calculation of the EKF filter gain is usually based on the linear approximation of the nonlinear system; if the high-order terms are considered, it involves the calculation of the Jacobian matrix and the Hessian matrix, and when the expression of the equivalent measurement has high-order nonlinear characteristics, it will make the calculation becomes very complicated; while ignoring higher-order terms inevitably leads to a decrease in estimation performance

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