CDSM-MMC electromagnetic transient overall modeling method and device based on weight method

Abstract

The invention discloses a CDSM-MMC electromagnetic transient overall modeling method and device based on a weight method. The method comprises the steps that initialization processing is conducted onsystem data; equivalently replacing a switching device in the sub-module with a double-value variable resistor, and discretizing a capacitor in the sub-module by adopting a weight numerical integration method; thevenin equivalent resistance and Thevenin equivalent voltage of each sub-module are calculated. Solving an equivalent model of the CDSM-MMC, so as to enable the equivalent model to carry out simulation operation; sorting the capacitor voltages of all the sub-modules of the MMC by adopting a classification sorting voltage-sharing algorithm to obtain a sorting result; judging whether thecurrent simulation moment is greater than the total simulation duration or not; if so, ending the simulation; If not, entering the next simulation moment, and determining the trigger state of the switching device of each bridge arm at the next simulation moment according to the sorting result and the number of capacitors and the bridge arm current which need to be input by each bridge arm at present. According to the invention, the weight coefficient can be flexibly adjusted according to the simulation requirement so as to obtain different stability and calculation precision.

Description

technical field [0001] The invention relates to the technical field of power system simulation modeling, in particular to a CDSM-MMC electromagnetic transient overall modeling method and device based on weighting method. Background technique [0002] Modular multilevel converter (MMC) has been widely used in various flexible DC transmission projects in the world. Compared with half bridge sub-module (HBSM) and full bridge sub-module The module (full bridge sub-module, FBSM) and the clamp double sub-module (clamp double sub-module, CDSM) can simultaneously isolate the DC short-circuit current and reduce costs, which have certain advantages. For CDSM-MMC with a high level number, the order of the admittance matrix of the nonlinear converter model is relatively high, which will make the conductance of the nonlinear converter model in the detailed electromagnetic transient simulation of CDSM-MMC The calculation of the nano matrix inversion is very large, which leads to the extr...

AI Technical Summary

Problems solved by technology

This model has high simulation accuracy, but it cannot be flexibly adjusted according to simulation requirements to obtain different performances such as stability and calculation accuracy.

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