According to the technical scheme provided by the present invention, the black-start speed and stability of the power grid are improved.

Abstract

The present invention provides a converter valve design method used for DC system black-start. The method comprises the steps of building a converter valve system simulation model; utilizing the converter valve system simulation model to obtain the voltage and the current stress in a converter valve and the loss of damping loops, a thyristor and a lightning arrester when a DC system is utilized to carry out the power grid black-start; configuring the parameters of the lightning arrester of the converter valve; utilizing the converter valve system simulation model and integrating the loss of different damping loops, the turn-on and turn-off loss of the thyristor and a converter valve phase commutation overshoot peak value to obtain an optimal scheme of the damping parameter configuration and the waterway configuration; analyzing the black-start operation capability of the converter valve, and determining whether the lightning arrester acts when the converter valve is at the power grid black-start by a leakage current waveform of the lightning arrester of the converter valve obtained by simulation; determining whether the converter valve can operate stably on the black-start condition by the loss of the lightning arrester. According to the technical scheme provided by the present invention, the black-start speed and stability of the power grid are improved.

Description

technical field [0001] The invention relates to a design method of a converter valve, in particular to a design method of a converter valve for black start of a direct current system. Background technique [0002] In the field of power grid black start technology, many years of theoretical research have been carried out at home and abroad from the selection of black start power supply, the rule strategy of the black start phase, and the optimization of power grid recovery paths, and a series of exchanges have been successfully carried out based on the research results. Grid black start test. Compared with the start-up of the AC system, the DC system has the characteristics of large transmission power, fast start-up and adjustment speed, and strong controllability. These characteristics can play a greater role in the early stage of black start, which can speed up networking and enhance power transmission. ability. However, it is still in its infancy to use the DC system to ...

AI Technical Summary

Problems solved by technology

However, it is still in its infancy to use the DC system to drive the black start of the power grid. It is also based on the ideal operating state of the converter equipment, and does not consider the capacity of the converter equipment to withstand the voltage, current and loss during the black start.

[0003] When the converter is black-started in the power grid, it will cause a series of problems such as increased commutation overshoot, increased loss of thyristors in the converter valve due to frequent switching off, increased transfer energy of arresters, etc.

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