发明名称 |
Negative sequence detector for a continuous wave frequency transducer |
摘要 |
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.
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申请公布号 |
US4723189(A) |
申请公布日期 |
1988.02.02 |
申请号 |
US19860945482 |
申请日期 |
1986.12.23 |
申请人 |
GENERAL ELECTRIC COMPANY |
发明人 |
LARSEN, EINAR V.;SHIFLETT, RUSSEL G. |
分类号 |
G01R29/16;G01R29/18;H02H3/34;H02H7/12;H02J3/34;H02M5/00;(IPC1-7):H02H3/26 |
主分类号 |
G01R29/16 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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