The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 2013
Filed:
Nov. 05, 2009
Mina Ogawa, Tokyo, JP;
Itaru Ando, Akita, JP;
Kiyoshi Ohishi, Niigata, JP;
Shoutaro Shindo, Niigata, JP;
Mina Ogawa, Tokyo, JP;
Itaru Ando, Akita, JP;
Kiyoshi Ohishi, Niigata, JP;
Shoutaro Shindo, Niigata, JP;
Hitachi Medical Corporation, Tokyo, JP;
Institute of National College of Technology, Tokyo, JP;
National University Cooperation Nagaoka University of Technology, Niigata, JP;
Abstract
An inverter circuit allowing a single drive circuit to perform both tracking control for tracking resonance frequency fluctuations caused by load fluctuations, and power control, thereby reducing switching loss. An inverter drive circuit part obtains a phase difference between output current and output voltage directed to a load circuit connected to a midpoint of two arm circuits of the inverter circuit, and controls a phase of the driving signal directed to each semiconductor switch such that the phase difference becomes zero or a predetermined value, enabling an operating frequency of the inverter circuit part to track a resonance frequency of the load circuit, and enabling a current phase to be delayed with respect to a voltage phase, thereby achieving ZCS. Since the phase difference is used, an auxiliary circuit is not necessary for measuring a current value in proximity to the semiconductor switches.