公开(公告)号：US10725107B2

公开(公告)日：2020-07-28

申请号：US15702182

申请日：2017-09-12

Applicant: ROLLS-ROYCE plc

Inventor： Sivakumar Nadarajan ,  Amit Gupta ,  Vaiyapuri Viswanathan ,  Chandana Gajanayake

IPC: G01R31/34 ,  G06F16/28 ,  H02P29/024 ,  H02P9/10 ,  H02P101/25 ,  H02P103/20 ,  F02C3/04

Abstract: A method of classifying a stator winding fault in a brushless synchronous generator includes measuring an electrical parameter of the stator winding and classifying the fault by calculating positive or negative sequence harmonics of the parameter and comparing one or more harmonic component to a threshold.

公开(公告)号：US09964600B2

公开(公告)日：2018-05-08

申请号：US14991139

申请日：2016-01-08

Applicant: ROLLS-ROYCE plc

Inventor： Chandana Jayampathi Gajanayake ,  Shantha Dharmasiri Gamini Jayasinghe ,  Sivakumar Nadarajan ,  Amit Kumar Gupta

IPC: G01R31/02 ,  G01R31/42

CPC classification number: G01R31/42

Abstract: A method of open-switch fault detection in a two-level voltage source power converter comprises the steps of: i. acquiring the waveforms of three-phase alternating current of the two-level voltage source power converter; ii. calculating at least a first time derivative of each acquired waveform; and iii. using the at least first time derivatives to determine whether an open-switch fault is present in the two-level voltage source power converter.

公开(公告)号：US09035689B2

公开(公告)日：2015-05-19

申请号：US14167088

申请日：2014-01-29

Applicant: ROLLS-ROYCE PLC

Inventor： Bikramjit Bhangu ,  Mohamed Halick Mohamed Sathik ,  Sivakumar Nadarajan ,  Chandana Jayampathi Gajanayake

IPC: H03K17/14 ,  G01K7/00

CPC classification number: H03K17/145 ,  H01L2924/0002 ,  H01L2924/00

Abstract: A thermal controller for driving a gate control unit of a gate-driven semiconductor switching device, the thermal controller comprising a junction temperature estimation module for generating an estimated junction temperature for the switching device, a gate voltage control module for modifying a gate voltage of the switching device, a switching frequency control module for modifying a switching frequency of the switching device, and a duty cycle control module for modifying the duty cycle of the switching device. In use, the thermal controller is adapted to activate one of the gate voltage control module, switching frequency control module and duty cycle control module dependent upon the estimated junction temperature in order to maintain the actual junction temperature below a pre-determined limit.

Abstract translation: 一种用于驱动栅极驱动半导体开关器件的栅极控制单元的热控制器，所述热控制器包括用于产生所述开关器件的估计结温的结温估计模块，用于修改所述栅极电压的栅极电压的栅极电压控制模块 开关装置，用于修改开关装置的开关频率的开关频率控制模块，以及用于修改开关装置的占空比的占空比控制模块。 在使用中，热控制器适于根据估计的结温激活门电压控制模块，开关频率控制模块和占空比控制模块中的一个，以便将实际结温保持在预定极限以下。