Robust dicyclic photovoltaic grid-connected control method based on power feedforward

Abstract

The invention discloses a robust dicyclic photovoltaic grid-connected control method based on power feedforward, which mainly comprises three parts: proportion integration (PI) control of exocyclic voltage, dead-beat control of endocyclic robust predictive current and power feedforward control, wherein the exocyclic PI control of the voltage is used for stabilizing the capacitive voltage of a direct-current side; the dead-beat control of the endocyclic robust predictive current is used for carrying out linear prediction on the voltage of a power grid at a next control period and carrying out non-linear prediction on grid-connected current by advanced control so as to obtain the command value of the grid-connected current at the next period; and then, PWM (pulse-width modulation) and grid-connected control are realized by the dead-beat control. According to the robust dicyclic photovoltaic grid-connected control method based on the power feedforward, a photovoltaic grid-connected inverter has higher robustness, wider stability margin and quicker dynamic response, and the requirement of grid-connected running of an inverter is better met.

Description

technical field [0001] The invention relates to the fields of smart grid and solar power generation, in particular to a robust double-loop photovoltaic grid-connected control method based on power feedforward. Background technique [0002] With the deterioration of the ecological environment and the depletion of non-renewable energy sources, energy conservation and emission reduction and new energy technologies have become current research hotspots. As an abundant non-polluting and clean energy, solar energy has become an important way to solve energy problems. As renewable energy is connected to the low-voltage distribution network through the construction of a distributed power generation structure, the grid-connected control strategy as a key technology for solar photovoltaic grid-connected power generation , and its research has received increasing attention. How to improve the overall conversion efficiency and power factor of the inverter, and reduce the distortion rat...

AI Technical Summary

Problems solved by technology

[0008] The technical problem to be solved by the present invention is to provide a robust double-loop photovoltaic grid-connected control method based on power feedforward to overcome the shortcomings of the existing double-closed-loop control method and solve the problems existing in deadbeat control. One-beat lag control, PWM action delay, dead time delay, and inductance parameter mismatch, etc.

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