Power sharing control method for open winding twin inverter photovoltaic power generation system

Abstract

The invention discloses a power sharing control method for an open winding twin inverter photovoltaic power generation system. In allusion to the problem of uneven power distribution of two inverterscaused by adopting a decoupling modulation strategy of 120-degree mutual difference in a common direct current bus open winding twin inverter photovoltaic power generation system, the invention bringsforward a power sharing control method based on reactive power compensation. According to the method, the reactive current command value of the two inverters is obtained by adjusting the active powerdifference of the two inverters, thus realizing the power sharing of the two inverters. Compared with an existing method, the invention has the following beneficial effects: the power quality of grid-connected current is not affected while realizing the control target, and the control method is simple and easy for engineering implementation.

Description

Technical field [0001] The invention belongs to the control technology of an open-winding dual inverter in the field of electrical engineering, and specifically relates to a power sharing control method of an open-winding dual inverter photovoltaic power generation system. Background technique [0002] As the power level of photovoltaic inverters continues to increase, multilevel inverter topology has become a key research object. Compared with the midpoint clamped and cascaded multilevel inverter topologies, the open-winding dual inverter topology can provide more levels and generate less output voltage when the number of switching devices is equal Harmonic has a higher DC side voltage utilization rate, so it has received extensive attention from many scholars. [0003] However, when the open-winding dual inverters share the DC bus, the circulating current between the two inverters needs to be suppressed. The typical solution is to use zero common mode voltage vector modulation o...

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to solve the problem of uneven distribution of active power between the two inverters that exists when the common DC bus open-winding double inverter adopts mutual difference 120 degree decoupling modulation, and proposes an open-winding based on reactive power compensation A power sharing control method for a dual-inverter photovoltaic power generation system. This method can realize the power sharing of dual-inverters without affecting the power quality of the grid-connected current, and the implementation process is simple, which overcomes the limitations of existing technical solutions. insufficient

Images