ALEXANDRIA, Va., June 25 -- United States Patent no. 12,341,448, issued on June 24, was assigned to Hitachi Industrial Equipment Systems Co. Ltd. (Tokyo).
"Power conversion device" was invented by Kazuaki Tobari (Tokyo), Yuta Iwase (Tokyo) and Yoshiyuki Taguchi (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "A power conversion device comprising, a power converter that outputs signal to the motor to vary the motor's output frequency, output voltage and output current and control unit that controls the power converter, the control unit is, calculating the first power from the output voltage and output current, calculating the second power from the output current, electrical circuit parameters and frequen...