Distributed photovoltaic inverter depth adjusting method and device

Abstract

The invention discloses a depth adjustment method and device for a distributed photovoltaic inverter. The adjustment method comprises the following steps: calculating a reference current instruction according to a system power reference instruction; extracting a reference current instruction and positive-sequence, negative-sequence and zero-sequence components of the output current of the inverter based on a reduced-order resonance regulator; independently carrying out closed-loop control on the positive sequence component, the negative sequence component and the zero sequence component; performing Park inverse transformation on a closed-loop control result to obtain an inverter output reference voltage; generating an inverter power device trigger pulse in response to the resulting reference voltage; acquiring three-phase voltage and current information of each feeder line in the power distribution area; and calculating three-phase power information of each feeder line, performing regulation and control by taking three-phase power balance as a target, generating a three-phase power reference instruction of each distributed photovoltaic inverter in the transformer area, and issuing the three-phase power reference instruction to the corresponding inverter. According to the technical scheme, deep adjustment of the distributed photovoltaic inverter is realized, and a new way is provided for operation control of a power distribution network.

Description

technical field [0001] The invention relates to the technical field of operation control of an AC distribution network, in particular to a method and device for depth adjustment of a distributed photovoltaic inverter. Background technique [0002] The distribution network has a wide coverage, complex and changeable structure, unbalanced access of a large number of single-phase loads in the distribution network and uncertainty of the load, which leads to the three-phase imbalance problem of the distribution network. In recent years, in order to alleviate energy problems, a large number of renewable resources such as distributed photovoltaic power sources have been connected to the power grid, which has changed the single trend direction of the distribution network. Three-phase unbalance problem. [0003] When the three-phase unbalance problem occurs in the distribution network, if it is not solved in time, it will bring about adverse consequences such as voltage waveform dis...

AI Technical Summary

Problems solved by technology

[0004] There are a large number of distributed photovoltaic inverters in the distribution network. The traditional operation mode has three-phase balanced output, and the regulation is relatively rough. It cannot provide support for a single phase. In order to fine-tune the regulation of distributed photovoltaic inverters, Realize deep adjustment, so as to better solve the three-phase unbalance problem in the distribution network platform area without adding phase-changing equipment. This invention proposes a distributed photovoltaic inverter depth adjustment based on a phase-splitting control strategy method

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