Title:
LEVEL CONTROL SYSTEM FOR RESERVOIR
Document Type and Number:
Japanese Patent JPS62233813
Kind Code:
A
Abstract:
PURPOSE:To attain the stable water control by applying a spectrum analysis to the water level signal including a periodic signal via the Fourier transformation to convert the level signal into the signal corresponding frequency component and using the signal obtained from the smoothing process as the water level signal via the inverse transformation. CONSTITUTION:The past storing level data obtained every 30sec are stored in a table T1 of a memory device set at a signal processing part 5. Then the data on the table T1 are stored in a table T2 after the Fourier transformation. The difference from the data having a period larger by 30sec than the power spectrum of the table T2 is calculated for each piece of data and stored in a table T3. Then the table T3 is searched to obtain the power and frequencies p1f1-p3f3 at the points where a code is changed to a positive state from a negative state. These points are connected with a straight line. Thus the data excluding the peak of the power spectrum is stored in a table T4. Then both real and imaginary number parts of the table T2 are corrected at the rates set before and after correction of the power spectrum and stored in a table T5 after the Fourier transformation. The time series of the corrected water level signal is used as the water level signals for control and calculation of the inflow.
Inventors:
ICHIYOSHI CHIYUUZABUROU
Application Number:
JP7655886A
Publication Date:
October 14, 1987
Filing Date:
April 04, 1986
Export Citation:
Assignee:
HITACHI LTD
International Classes:
G05D9/12; (IPC1-7): G05D9/12
Attorney, Agent or Firm:
Katsuo Ogawa
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