Topology structure, grid-connected system and control method of an offshore wind farm

Abstract

The invention discloses a topological structure, a grid-connected system and a control method of an offshore wind power plant; the offshore wind power plant comprises an N blowers and (N-1) sets of shunt circuits; the DC (Direct Current) output ends of the N blowers are connected in series in sequence; starting from the first one of the blowers connected in series, each two blowers are used one blower group, that is, the nth blower and the (n+1)th blower are utilized as one blower group, wherein N ranges from 1 to N-1; each blower group is connected in parallel with one set of the shunt circuit; the control method comprises the steps: when the port voltage of the previous blower of the blower group is lower than a rated voltage, controlling the shunt circuit to inject negative current to the blower group; when the port voltage of the previous blower of the blower group is higher than the rated voltage, controlling the shunt circuit to inject positive current to the blower group. Each blower is capable of independently finishing maximum-power tracking, and an offshore converter station and an offshore electric platform are cancelled; the construction of an offshore wind power generation system is reduced and the total energy loss of the system is reduced.

Description

technical field [0001] The invention relates to a distributed power supply, which belongs to the technical field of wind power generation, in particular to a topology structure, a grid-connected system and a control method of a large-scale offshore wind power farm. Background technique [0002] In today's world, energy issues have gradually become the focus of research in countries all over the world. It has become an inevitable trend of energy development to seek various new energy sources to replace the increasingly depleted fossil fuels. As a non-polluting and renewable new energy, wind energy has great development potential. Seeking solutions for the construction of large-scale wind farms, especially for the construction of large-scale offshore wind farms, has become the main research direction of scholars from all over the world. [0003] At present, the large-scale wind farms that have been built are mainly located on land or on islands, but onshore wind energy is li...

AI Technical Summary

Problems solved by technology

This kind of wind farm saves the construction of offshore converter stations and offshore electrical platforms, but the simple series connection of the wind turbines makes the output power of each wind turbine affect each other. Since the wind power captured by each wind turbine is difficult to be equal, the phenomenon of "abandoned wind" will inevitably occur. The phenomenon of "abandoned wind" means that when the DC output voltage of each fan is equal, the current flowing in the series cluster is limited by the fan with the smallest power to capture the wind, so that the output power of other fans is reduced, and a part of the wind power must be discarded.

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