JPS55131781A - Frequency detector - Google Patents
Frequency detectorInfo
- Publication number
- JPS55131781A JPS55131781A JP3962079A JP3962079A JPS55131781A JP S55131781 A JPS55131781 A JP S55131781A JP 3962079 A JP3962079 A JP 3962079A JP 3962079 A JP3962079 A JP 3962079A JP S55131781 A JPS55131781 A JP S55131781A
- Authority
- JP
- Japan
- Prior art keywords
- cos
- data
- voltage
- frequency
- memorized
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
PURPOSE: To accomplish higher accuracy and higher speed by conducting a comparison, calculation and checking employing several sampling data and settling values in the determination of frequency computed with an aid of data digitalized obtained from the sampling of voltage in the power system.
CONSTITUTION: AC voltage 1 is inputted into a sample hold circuit 2 whose output is converted into a digital data with an AD converter whereby sampling data ViW Vi+4 is memorized in the input data memory 4A. The arithmetic section 11A performs a processing to compute cos 2ϕ, namely, (Vi 2-Vi+4 2)/2(Vi+1 2-Vi+3 2) and Vi+1 2-Vi+3 2=0 is determined by the comparator 14A. When Yes is given, outputted is the frequency which has been memorized in the output data memory circuit 14A immediately before the inputting of the voltage 1. On the other hand, when No is given, after the computation of cos 2ϕ in the arithmetic section 11A, the memorized value of cos 2ϕ is readout from the memory circuit 12A to check whether it coincides the result of the computation by means of the coincidence circuit 9A. When the coincidence signal is detected, the frequency f corresponding to cos 2ϕ thus computed is outputted from the gates 13A and 15A.
COPYRIGHT: (C)1980,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3962079A JPS55131781A (en) | 1979-04-02 | 1979-04-02 | Frequency detector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3962079A JPS55131781A (en) | 1979-04-02 | 1979-04-02 | Frequency detector |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS55131781A true JPS55131781A (en) | 1980-10-13 |
Family
ID=12558146
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3962079A Pending JPS55131781A (en) | 1979-04-02 | 1979-04-02 | Frequency detector |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS55131781A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4633516A (en) * | 1985-05-30 | 1986-12-30 | United States Of America As Represented By The Secretary Of The Air Force | Instantaneous frequency measurement receiver with digital processing |
-
1979
- 1979-04-02 JP JP3962079A patent/JPS55131781A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4633516A (en) * | 1985-05-30 | 1986-12-30 | United States Of America As Represented By The Secretary Of The Air Force | Instantaneous frequency measurement receiver with digital processing |
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