• DocumentCode
    2563322
  • Title

    A precision thermal wattmeter having a sampling control system and an analogue feedback loop

  • Author

    Takahashi, K. ; Kusui, S.

  • Author_Institution
    Japan Electr. Meters Inspection Corp., Tokyo, Japan
  • fYear
    1990
  • fDate
    11-14 June 1990
  • Firstpage
    320
  • Lastpage
    321
  • Abstract
    A precision thermal wattmeter having a sampling control system and an analog feedback loop is described. A pair of thermal converters is used as a sum and difference multiplier and as an AC/DC power comparator simultaneously. The large error caused by insufficient open-loop gain in the wattmeter is removed by the sampling control system. The wattmeter is designed for use at relatively low frequency. The maximum sensitivity is better than 1 p.p.m., and total accuracy is estimated at better than 20 p.p.m.<>
  • Keywords
    comparators (circuits); computerised control; computerised instrumentation; convertors; feedback; wattmeters; AC/DC power comparator; analogue feedback loop; error; sampling control; sum and difference multiplier; thermal converters; thermal wattmeter; Analog-digital conversion; Control systems; Equations; Feedback circuits; Feedback loop; Open loop systems; Sampling methods; Thermal force; Voltage; Wattmeters;
  • fLanguage
    English
  • Publisher
    ieee
  • Conference_Titel
    Precision Electromagnetic Measurements, 1990. CPEM '90 Digest., Conference on
  • Conference_Location
    Ottawa, Ontario, Canada
  • Type

    conf

  • DOI
    10.1109/CPEM.1990.110041
  • Filename
    110041