Automatic identification and empty-fetch protection method for photovoltaic water pump frequency converter

• Main Authors: CHEN MING, ZHANG SHENGJIE, MA ZHIBAO, YAO JUN, PENG KAI, XIE FUHUA, ZHU GUOJUN, QU XIAOLI
• Format: Patent
• Language: Chinese; English
• Published: 11.07.2012
• Subjects: CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; GENERATION

The invention discloses an automatic identification and empty-fetch protection method for a photovoltaic water pump frequency converter. A digital signal processor (DSP) is used for continuously sampling the input voltage and the input current of the photovoltaic water pump frequency converter within a plurality of periods, calculating the input power of the photovoltaic water pump frequency converter, comparing the input power with the actual operation power of the photovoltaic water pump under the present frequency of the frequency converter, simultaneously monitoring the voltage deflection of a DC bus of the photovoltaic water pump frequency converter, further judging the balance relationship between the input power of the photovoltaic water pump frequency converter and the actual operation power of the photovoltaic water pump under the present frequency of the frequency converter, and outputting a corresponding control signal to the control the photovoltaic water pump, so as to achieve automatic identific