Adaptive distance protection strategy based on dynamic equivalent impedance of photovoltaic power station

• Main Authors: JIN ENSHU, HAN HUI, HAN BAOCAI, GAOSIRIGULENG, KONG BO, CHEN LIANJUN, ZHANG JIAYU
• Format: Patent
• Language: Chinese; English
• Published: 06.03.2018
• Subjects: CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; GENERATION

The present invention relates to the field of relay protection technology, and provides an adaptive distance protection strategy based on a dynamic equivalent impedance of a photovoltaic power station. The method comprises the steps of: employing an illumination intensity and a temperature, factory parameters, parameters of a chopper circuit, parameters of an inverter, parameters of a filter, parameters of a transformer, a grid-connected voltage of a photovoltaic module and the like to define a mathematical model of a dynamic equivalent impedance of a photovoltaic power station; employing thedynamic equivalent impedance Zps to calculate a dynamic branch coefficient kD; and obtaining a dynamic setting valve Zset of an adaptive distance protection section II. The adaptive distance protection strategy based on the dynamic equivalent impedance of the photovoltaic power station can effectively solve the non-act problem of the distance protection section II being taken as backup protectionby accessing a photovoltai