Impedance detection method for diesel generator system performing parallel current sharing with energy storage converter

Abstract

The invention discloses an impedance detection method for a diesel generator system performing parallel current sharing with an energy storage converter. The method comprises the steps: building a detection rotating coordinate system, and detecting and calculating a no-load voltage of a diesel generator and system impedances in different load levels; calculating the system mean impedance through astatistical method; finally setting the output impedance of the energy storage converter according to the capacity ration of the diesel generator and the energy storage converter. According to the invention, the detected impedance of the diesel generator system is set in the energy storage converter according to the capacity ratio, thereby enabling the energy storage converter to have the same output characteristics as the diesel generator, enabling the output power to be distributed according to the capacity ratio when the energy storage converter and the diesel generator perform the parallel load operation, guaranteeing that there is no parallel loop current between the energy storage converter and the diesel generator and enabling the energy storage converter and the diesel generator to have the good parallel operation characteristics.

Description

technical field [0001] The invention relates to power electronics technology, in particular to an impedance detection method of a diesel generator system connected in parallel with an energy storage converter for current sharing. Background technique [0002] An independent power generation system in which diesel generators and energy storage converters operate in parallel is a power system that operates independently in areas isolated from large power grids, and is often used in remote mountainous areas, isolated islands and other areas. The two are connected in parallel to supply power to the load to improve the economy of power generation, reduce environmental pollution, and enhance the self-sufficiency of power supply in remote areas. However, there is a large difference in the impedance characteristics of the output port between the diesel generator and the energy storage converter, which makes it difficult to control the parallel connection of the energy storage conver...

AI Technical Summary

Problems solved by technology

However, there is a large difference in the impedance characteristics of the output port between the diesel generator and the energy storage converter, which makes it difficult to control the parallel connection of the energy storage converter and the generator in the form of a voltage source, and current circulation may occur after parallel connection , if the circulating current flows to the generator, the generator absorbs power and may damage the diesel generator