Photovoltaic inverter correction control method based on voltage out-of-limit risk

Abstract

The invention discloses a photovoltaic inverter correction control method based on a voltage out-of-limit risk, and the method comprises the steps: collecting a time sequence value and a section valueof a photovoltaic inverter, and constructing a time sequence prediction model and a risk prediction model; constructing a time sequence risk prediction model based on the time sequence prediction model and the risk prediction model, and performing calculation; constructing a photovoltaic inverter correction control algorithm based on the calculation result; and controlling the output of the photovoltaic inverter based on the photovoltaic inverter correction control algorithm. According to the method, real-time photovoltaic inverter output is controlled through prediction of a probability model of photovoltaic output in the future and prediction simulation based on a time sequence, and compared with traditional voltage reactive power control, the correction control method can remarkably improve the situations of voltage out-of-limit and voltage fluctuation.

Description

technical field [0001] The invention relates to the technical field of energy systems, in particular to a correction control method for a photovoltaic inverter based on the risk of voltage exceeding the limit. Background technique [0002] Photovoltaic (PV) is a very popular renewable energy source, and the integration of PV into the grid is rapidly increasing due to its environmental protection and investment value; however, due to unpredictable weather, cloud movement, temperature and other natural conditions The resulting voltage fluctuation problem causes the output of photovoltaic power generation to be highly variable and intermittent, which also brings the risk of voltage fluctuation and over-limit. [0003] At present, for the evaluation of photovoltaic voltage fluctuation, most of them use voltage variance as the evaluation index, and use the variance of voltage fluctuation to deviate from the rated working voltage to characterize the fluctuation. However, the volta...

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Problems solved by technology

[0002] Photovoltaic (PV) is a very popular renewable energy source, and the integration of PV into the grid is rapidly increasing due to its environmental protection and investment value; however, due to unpredictable weather, cloud movement, temperature and other natural conditions The resulting voltage fluctuation problem leads to the highly variable and intermittent output of photovoltaic power generation, which also brings the risk of voltage fluctuation and over-limit

[0003] At present, for the evaluation of photovoltaic voltage fluctuation, most of them use voltage variance as the evaluation index, and use the variance of voltage fluctuation to deviate from the rated working voltage to characterize the fluctuation. However, the voltage deviation based on the current time section does not combine the voltage development. Trend and risk comprehensive judgment control, the control signal has a time lag, which has an important impact on the voltage stability of photovoltaics and the system. Once a huge deviation occurs, it will not be able to respond to the impact in time, leading to the problem of cascading voltage over-limit faults in the system

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