MMC simulation model and method based on submodule DC voltage control closed loop

Abstract

The invention relates to an MMC simulation model and method based on a submodule DC voltage control closed loop. According to the system, the alternating current side of each detailed model sub-module is equivalent to two controlled voltage sources, the direct current side of each detailed model sub-module is equivalent to a controlled current source, a capacitor and a resistor which are connected in parallel, and an equivalent model sub-module is formed; the plurality of equivalent model sub-modules form an MMC equivalent simulation model. The method comprises: generating a bridge arm switching function by using the ratio of the bridge arm modulation wave of the MMC equivalent simulation model to the DC voltage of the MMC equivalent simulation model; forming a closed loop by using the direct-current voltage of the equivalent model sub-module and a bridge arm switching function; based on the bridge arm switching function and the closed loop, generating an equivalent model sub-module switching function; and replacing the on-off process of the equivalent model sub-module with a continuous equivalent model sub-module switching function. According to the method, the simulation speed can be improved while the electrical quantity characteristics of the MMC detailed switch model are reserved.

Description

technical field [0001] The invention relates to the simulation field of a modular multi-level converter (Modular Multi-level Converter, MMC), in particular to an MMC simulation model and method based on a sub-module DC voltage control closed loop. Background technique [0002] With the rapid development of science and technology and social economy in various countries, countries around the world are paying more and more attention to new energy power generation, and have invested a lot of money in technology to support the research and development of new energy technology. Due to the decentralized nature of wind power and solar power generation, they are far from the main grid. Some new problems arise after they are connected to the AC and DC grids. The Voltage Source Converter-High Voltage Direct Current (VSC-HVDC) technology based on voltage source commutation converters is an important way to increase the proportion of renewable energy. An effective way to connect distribu...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a MMC simulation model and method based on sub-module DC voltage control closed-loop, to solve the problem that the sub-module characteristics of MMC cannot be taken into account, and the simulation speed is low

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