P

Inventor

NAKAGAWA HIROTO

JP29 patents
⚠️ This page may combine multiple inventors who share the name “NAKAGAWA HIROTO”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.

HITACHI LTD

19 patents
US5026256AJun 25, 1991

Variable speed pumping-up system

HITACHI LTD102 citations95
US4754156AJun 28, 1988

Control apparatus for variable-speed hydraulic power generating system

HITACHI LTD66 citations95
US4812729AMar 14, 1989

Protecting apparatus for secondary excitation type variable speed AC generator/motor

HITACHI LTD64 citations94
US4694189ASep 15, 1987

Control system for variable speed hydraulic turbine generator apparatus

HITACHI LTD85 citations94
US5561358AOct 1, 1996

Variable speed pumping-up generator

HITACHI LTD22 citations92
US4920277AApr 24, 1990

Control system for a variable speed hydro-power plant apparatus

HITACHI LTD43 citations92
US4823018AApr 18, 1989

Control system for variable speed water-wheel generator apparatus

HITACHI LTD37 citations92
US4952852AAug 28, 1990

Power system and synchronizing breakers for a variable speed generator motor system

HITACHI LTD48 citations91
US4812730AMar 14, 1989

Variable-speed generator/motor system

HITACHI LTD28 citations89
US6336322B1Jan 8, 2002

Method of controlling a pump turbine

HITACHI LTD16 citations80
US5099409AMar 24, 1992

Semiconductor electric power conversion system enabling fault and/or overtemperature protection

HITACHI LTD20 citations80
US4870339ASep 26, 1989

Variable-speed power generating system

HITACHI LTD22 citations80
US9629052B2Apr 18, 2017

Traffic management server

HITACHI LTD2 citations73
US5456115AOct 10, 1995

Method of counterflow through a pump and method of controlling the operation of a pump in a pumping installation

HITACHI LTD9 citations72
US5265002ANov 23, 1993

Fault protection for a multiphase bridge power converter

HITACHI LTD15 citations72
US5090872AFeb 25, 1992

Method of controlling the operation of a pump in a pumping installation by detecting counterflow

HITACHI LTD11 citations72
US4766360AAug 23, 1988

Induction generator/motor system

HITACHI LTD9 citations72
US4980629ADec 25, 1990

AC-excited generator/motor apparatus

HITACHI LTD13 citations70
US4743826AMay 10, 1988

Pumping-up generator/motor system and method of operation of the same

HITACHI LTD4 citations60

TOYOTA MOTOR CO LTD

6 patents

NAKAGAWA HIROTO

2 patents

(unassigned)

1 patent

ANANDENKI CO LTD

1 patent