Photovoltaic power generation virtual inertia compensation system and method based on super capacitor energy storage

Abstract

The invention discloses a photovoltaic power generation virtual inertia compensation system based on super capacitor energy storage. The photovoltaic power generation virtual inertia compensation system comprises a photovoltaic array, a boosted circuit and a grid-connected inverter which are electrically connected in sequence, the system also comprises a super capacitor assembly used for energy storage, a bidirectional DC-DC converter and a virtual inertia control module. One end of the bidirectional DC-DC converter is electrically connected with the output end of the unidirectional DC-DC boosted circuit and the input end of the grid-connected inverter, and the other end of the bidirectional DC-DC converter is electrically connected with the super capacitor assembly; and the bidirectionalDC-DC converter comprises a power switching device. The virtual inertia control module comprises a first inverse adder, a virtual inertia converter, a second inverse adder, a first PI controller, a third inverse adder, a second PI controller and a PWM (pulse width modulator-demodulator) which are electrically connected in sequence, and the PWM outputs a pulse signal to control the on-off of the power switching device of the bidirectional DC-DC converter. According to the present invention, the influence of frequency noise on the system stability can be avoided.

Description

technical field [0001] The invention relates to the technical field of smart grid control, in particular to a photovoltaic power generation virtual inertia compensation system and method based on supercapacitor energy storage. Background technique [0002] At present, with the depletion of traditional fossil energy and the increasingly serious environmental pollution, new energy power generation has received more and more attention. Compared with traditional energy sources, photovoltaic power generation systems have many advantages, so they have broad development and application prospects in the world's energy distribution pattern. In order to maximize the use of sunlight resources, photovoltaic power generation systems usually adopt maximum power tracking control strategies, which cannot respond to grid frequency changes, and photovoltaic power generation systems usually use power electronic inverters as interface devices with large power grids. Power electronic devices are...

AI Technical Summary

Problems solved by technology

Its energy source is mainly realized through photovoltaic load shedding and energy storage batteries on the DC side. The photovoltaic load shedding scheme has limited support capacity and will lead to the inability to maximize the use of light energy and reduce the economic benefits of the photovoltaic power generation system; while the DC side The dynamic response speed of the configured energy storage battery is slow, and it cannot quickly provide inertia response for the system

At the same time, virtual synchronous machine technology is also susceptible to system frequency noise, causing power fluctuations

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