Control system for multi-module photovoltaic grid-connected inverter

Abstract

The embodiment of the invention provides a control system for a multi-module photovoltaic grid-connected inverter. The inverter comprises a plurality of inverter modules. The control system comprises a plurality of first control modules and a second control module, wherein the plurality of first control modules are respectively connected with the plurality of inverter modules and used for acquiring module operation data of each inverter module as well as transmitting the module operation data to the second control module through a communication bus; the second control module is connected with the plurality of first control modules through communication buses and used for sending an inverter control instruction to the plurality of first control modules as well as acquiring the module operation data of the inverter modules, acquired by the plurality of first control modules. With the adoption of the system, the demand on hardware resource of a controller can be reduced; in addition, the hardware structure of the controller is simplified, and meanwhile, the generation loss caused by fault can be reduced.

Description

technical field [0001] The invention relates to the technical field of photovoltaic grid-connected power generation, in particular to a control system for a multi-module photovoltaic grid-connected inverter. Background technique [0002] An inverter is a power conversion device that converts direct current into alternating current, and is an important power conversion device in a photovoltaic power generation system. [0003] With the development of power electronics technology, the development of photovoltaic grid-connected inverter technology has become relatively mature. Among them, high-power photovoltaic grid-connected inverters are mainly divided into two types: centralized type and modular type. Here, for the modular inverter, it uses multiple inverter modules in parallel to expand the system power level and meet the needs of high-power photovoltaic power generation occasions; in addition, it can realize N+1 or N+M redundancy Yu design, when one or more of the invert...

AI Technical Summary

Problems solved by technology

[0005] At present, the commonly used modular inverter control system, such as figure 1 As shown, one inverter controller controls N parallel inverter modules 111-11n, and this inverter controller must complete the signal collection and monitoring of N inverter modules, and at the same time send Other external devices (for example, host computer, man-machine display interface, etc.) send the collected signals of the inverter module. The control system of this structure has a large demand for the hardware resources of the inverter controller itself, and will make the The controller circuit board has a large area, which is not easy to install; at the same time, when a certain inverter module fails, the entire system needs to be shut down for maintenance, which will cause a large loss of power generation

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