Title:
ELECTRIC ANGLE DETECTOR FOR SYNCHRONOUS MOTOR
Document Type and Number:
Japanese Patent JP3358504
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To exclude an influence by the change of a filter or change of characteristics, by executing detection of a current value after a predetermined time corresponding to the time constant of the filter is elapsed from the application of a voltage.
SOLUTION: A CPU 120 further waits for the elapse of a predetermined detecting period after stopping a voltage application, detects a current value via a current sensor 102, and detects an electric angle by using the current value. And, the period is set so as to satisfy the condition that the period is sufficiently longer than the time constant of a filter 106. Thus, since a time delay is incorporated in the detection of the current and hence the current can be detected without influence by a delay in rise of the current by the filters 106, 108, the angle can be accurately obtained. And, even if characteristics of the filter 106 are changed, a desired current value can be detected. And, the angle can be accurately obtained.
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Inventors:
Eiji Yamada
Yasumi Kawabata
Yasumi Kawabata
Application Number:
JP22010497A
Publication Date:
December 24, 2002
Filing Date:
July 30, 1997
Export Citation:
Assignee:
TOYOTA JIDOSHA KABUSHIKI KAISHA
International Classes:
H02P23/00; H02P21/05; H02P21/22; H02P23/04; H02P25/022; H02P25/026; H02P25/10; (IPC1-7): H02P5/28; H02P7/36
Domestic Patent References:
| JP4359691A | ||||
| JP5137385A | ||||
| JP389888A |
Attorney, Agent or Firm:
Takashi Shimode (2 others)
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