Title:
【発明の名称】連続波周波数変換器用の逆相分検出装置
Document Type and Number:
Japanese Patent JP2758402
Kind Code:
B2
Abstract:
A negative sequence occurring in a polyphase power system control including a continuous wave frequency transducer causes a second harmonic to be generated which for a 60 Hz system comprises a 120 Hz signal. In a preferred embodiment of the invention, the continuous wave frequency transducer includes an active 120 Hz notch filter having one stage which provides a component of the 120 Hz second harmonic. This signal is coupled to a second harmonic detector implemented by a semiconductor diode connected to the output of an operational amplifier. The detector diode is coupled to one input of a comparator circuit whose other input is coupled to a selectable DC reference signal. The comparator operates to generate a fault indicating signal indicative of a negative sequence when the output from the second harmonic detector exceeds the reference. The fault indicating signal is thereafter converted to a digital type signal which can be utilized by external utilization circuitry such as a system control circuit or a diagnostic subsystem.
Inventors:
EINAA BAUN RAASEN
RATSUSERU JERARUDO SHIFURETSUTO
RATSUSERU JERARUDO SHIFURETSUTO
Application Number:
JP32423887A
Publication Date:
May 28, 1998
Filing Date:
December 23, 1987
Export Citation:
Assignee:
JENERARU EREKUTORITSUKU CO
International Classes:
G01R29/16; G01R29/18; H02H3/34; H02H7/12; H02J3/34; H02M5/00; (IPC1-7): H02H3/34; H02J3/34
Attorney, Agent or Firm:
Tokunji Ikunuma