Order reduction method for LCL-T module of photovoltaic power generation system

• Main Authors: YU XIN, CUI YONG, BAO HAILONG, JIN ENSHU, GUO QIANG, YANG XIAOFAN, DENG FOLIANG
• Format: Patent
• Language: Chinese; English
• Published: 20.09.2019
• Subjects: CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

The invention relates to an order reduction method for an LCL-T module of a photovoltaic power generation system, which comprises the steps of in the case that an isolation transformer is unsaturated, building a mathematical model based on the LCL-T module of the photovoltaic power generation system, acquiring transfer functions between input voltage of a filter and output current of the filter and between the input voltage of the filter and primary side current of the transformer, and introducing weighted feedback current so as to realize zero and pole cancellation and achieve the purpose of simplification; and in the case that the isolation transformer is saturated, solving a transfer function between the input voltage of the filter and primary side output current of the transformer in consideration of primary and secondary side resistance and excitation resistance of the isolation transformer, and reducing the high-order LCL-T module into a first-order system with series connection of an equivalent resisto