ALEXANDRIA, Va., March 19 -- United States Patent no. 12,255,464, issued on March 18, was assigned to Huawei Digital Power Technologies Co. Ltd. (Shenzhen, China).
"Islanding detection method and apparatus" was invented by Xiongfei Wang (Aalborg, Denmark), Fangcheng Liu (Shenzhen, China) and Teng Liu (Aalborg, Denmark).
According to the abstract* released by the U.S. Patent & Trademark Office: "An islanding detection method includes: an alternating current frequency of an inverter is monitored. The alternating current frequency fluctuates within a preset range when in a normal mode. When an instantaneous shifting value of the alternating current frequency exceeds the preset range, a frequency detected before instantaneous shifting is a fi...