Calculation method for fixed DC voltage controller parameter of voltage source converter

Abstract

The invention relates to a calculation method for a fixed DC voltage controller parameter of a voltage source converter. An equivalent model of the voltage source converter comprises a three-phase equivalent power voltage, a power grid equivalent resistor, a power grid equivalent inductor and a voltage source converter and is characterized in that the method comprises the following steps of I, building a simplified equivalent model of the voltage source converter; II, building an electromagnetic transient model of the equivalent model; III, figuring out an active power small-interference linear model of the voltage source converter; IV, building a small-interference linear Thevenin equivalent model of the voltage source converter; V, building an equivalent DC system model and an equivalent DC system small-interference model of a fixed DC voltage controller of the voltage source converter; and VI, calculating the parameter of the fixed DC voltage controller of the voltage source converter. According to the method, the equivalent DC system small-interference model of the fixed DC voltage controller of the voltage source converter is built, the system order is reduced, and the accuracy of the controller parameter is improved.

Description

technical field [0001] The invention relates to the technical field of flexible high-voltage direct current transmission, in particular to a method for calculating parameters of a constant direct current voltage controller of a voltage source converter. Background technique [0002] Voltage source converter (voltage source converter, VSC) plays an important role in the field of power conversion, where VSC can be in the form of modular multilevel converter (MMC), or two-level or three-level form. The VSC-based flexible DC transmission technology is a new type of power transmission technology following the AC transmission and conventional DC transmission technologies, and its emergence has brought the power transmission technology to a new level. Since active power and reactive power can be independently controlled and power flow reversal is easy to achieve, it has major technical advantages in new energy generation grid connection and consumption, transnational power trading...

AI Technical Summary

Problems solved by technology

According to the principle of power balance, the active power input to the VSC on the AC side is equivalent to the sum of the output power on the DC side and the absorbed power of the capacitor, which can simplify the analysis of the dynamic behavior characteristics of the VSC and help to establish a small-disturbance linearization mathematics of the VSC with a lower order Model, so as to quantitatively design the parameters of the constant DC voltage controller, but when calculating the parameters of the constant DC voltage outer loop controller, some ignore the influence of the DC current on the entire system, and some only give the selection range of the parameters , and no quantitative calculation of the controller parameters

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