Control method suitable for bidirectional DC-AC converter of alternate current and direct current hybrid microgrid

Abstract

The invention relates to a bus voltage stability technology of an alternate current and direct current hybrid microgrid, in particular to a control method suitable for a bidirectional DC-AC converterof the alternate current and direct current hybrid microgrid. According to the method, partitioning control is conducted on voltage fluctuation aiming at the existing problem of power imbalance of thealternate current and direct current hybrid microgrid; the method is divided into an off-grid state and a grid-connected state, under the grid-connected state, partitioning is conducted according tothe voltage deviation value of a direct current bus, and different droop slopes are adopted in different partitions; under the off-grid state, working modes are chosen taking the energy supply and load consumption of an alternate current sub microgrid and a direct current sub microgrid into consideration, and meanwhile multi-slope droop control is adopted to achieve the partitioning curve dynamicdroop control of the alternate current and direct current hybrid microgrid; the control method of the bidirectional DC-AC converter of the alternate current and direct current hybrid microgrid under different states is provided, a multi-slope droop curve is adopted, the multi-slope droop curve is close to a real droop curve, and the control precision of the microgrid is ensured.

Description

technical field [0001] The invention belongs to the technical field of bus voltage stability design of an AC-DC hybrid micro-grid, and in particular relates to a control method for a bidirectional DC-AC converter suitable for an AC-DC hybrid micro-grid. Background technique [0002] my country is facing the need for energy transformation. In order to achieve energy transformation, increase the penetration rate of renewable energy, and promote distributed power generation on a large scale, it is a more feasible solution. At the same time, with the development of science and technology, a large number of DC power equipment is also booming. The use of AC and DC power supply systems can not only meet the user's AC power demand, but also meet the user's DC load, and at the same time reduce energy consumption in AC and DC. loss during conversion. The AC-DC hybrid microgrid has broad prospects in China's energy transition stage. [0003] Compared with DC microgrid and AC microgri...

AI Technical Summary

Problems solved by technology

Therefore, there is a problem that the traditional droop curve adopts a fixed slope and the capacitor charge and discharge curve is out of sync.

Images