Inventor · Champaign, IL, US

Philip T. Krein

41Patents
23h-index
29Co-inventors
85Inventor score

Filing activity: Aug 26, 1986 → Dec 8, 2015

Most-cited inventions

PatentTitleAreaCited byStatus
US5801519A Self-excited power minimizer/maximizer for switching power converters and switching motor drive applications Emerging Cross-Sectional Technologies 367 Expired
US7945413B2 Voltage-sensed system and method for anti-islanding protection of grid-connected inverters Electricity 199 Active
US5710504A Switched capacitor system for automatic battery equalization Emerging Cross-Sectional Technologies 173 Expired
US7078883B2 Method and apparatus for starting power converters Emerging Cross-Sectional Technologies 173 Expired
US4707845A Touch panel with automatic nulling Physics 150 Expired
US4698460A Touch panel system Physics 126 Expired
US8284574B2 Method and apparatus for controlling an inverter using pulse mode control Emerging Cross-Sectional Technologies 107 Active
US4698461A Touch panel with automatic frequency control Physics 102 Expired
US5668464A Feedforward active filter for output ripple cancellation in switching power converters Physics 76 Expired
US9143053B1 Microinverters for employment in connection with photovoltaic modules Emerging Cross-Sectional Technologies 60 Active
US7663342B2 Apparatus, system, and method for controlling multiple power supplies Electricity 57 Active
US8279642B2 Apparatus for converting direct current to alternating current using an active filter to reduce double-frequency ripple power of bus waveform Electricity 51 Active
US6700803B2 Systems and methods for pulse width modulation Electricity 39 Expired
US8350411B2 Modular system for unattended energy generation and storage Electricity 32 Active
US7994657B2 Modular system for unattended energy generation and storage Electricity 32 Active
US8482947B2 Apparatus and method for controlling DC-AC power conversion Electricity 27 Active
US8325499B2 Methods for minimizing double-frequency ripple power in single-phase power conditioners Emerging Cross-Sectional Technologies 26 Active
US9093919B2 Apparatus for converting direct current to alternating current using a frequency converter Electricity 25 Active
US8842454B2 Inverter array with localized inverter control Emerging Cross-Sectional Technologies 24 Active
US7755916B2 Methods for minimizing double-frequency ripple power in single-phase power conditioners Emerging Cross-Sectional Technologies 24 Active
US8737100B2 Method and apparatus for controlling an inverter using pulse mode control Emerging Cross-Sectional Technologies 24 Active
US7681090B2 Ripple correlation control based on limited sampling Electricity 23 Active
US7982434B2 Apparatus and method for controlling a power supply Electricity 23 Active
US8004865B2 Methods for minimizing double-frequency ripple power in single-phase power conditioners Emerging Cross-Sectional Technologies 21 Active
US8423312B2 Voltage-sensed system and method for anti-islanding protection of grid-connected inverters Electricity 21 Active

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.