Microprocessor Control of Phase-Controlled Converters and Cycloconverters

  • S. K. Tso
Part of the International Series on Microprocessor-Based Systems Engineering book series (ISCA, volume 1)


Phase-controlled thyristor converters [1, 2] provide AC/DC controlled power conversion. Depending on the circuit arrangement power can flow in either direction, the converters thereby acting respectively as controlled rectifiers or synchronous inverters. Apart from low-power systems the AC supply used is normally three-phase, or multi-phase as derived from suitable transformer connections or otherwise. The thyrisors in the converter are sequentially triggered into conduction and in the normal process of switching, the device(s) previously conducting will experience a reverse bias, presented by the supply voltage, and turn off after a short period of time. This mechanism is known as “natural commutation”, because no additional or external means is utilised for device turn-off or commutation purposes.


Output Voltage Phase Control Pulse Number Firing Control Timing Wave 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Schaefer, J .: ‘Rectifier Circuits, Theory and Design’ (Wiley, 1965).Google Scholar
  2. 2.
    Pelly, B.R .: ‘Thyristor phase-controlled converters and cycloconvert- ers’ (Wiley-Interscience, 1971).Google Scholar
  3. 3.
    McMurray, W .: ‘The theory and design of cycloconverters’ (MIT Press, 1972).Google Scholar
  4. 4.
    Gyugyi, L., and Pelly. B.R.: ‘Static power frequency changers’ (Wiley-Interscience, 1976).Google Scholar
  5. 5.
    Chen, H.H .: ‘A microprocessor control of a three-pulse cycloconvert- er’, IEEE Trans., 1977, IECI-24, pp. 226–230.Google Scholar
  6. 6.
    Singh, D., and Hoft, R.G.: ‘Microcomputer-controlled single-phase cycloconverter’, IEEE Trans., 1978, IECI-25, pp. 233–238.Google Scholar
  7. 7.
    Tso, S.K., Spooner, E.D., and Cosgrove, J.: ‘Efficient microprocessor-based cycloconvertor control’, IEE Proc. B, 1980, 127, pp. 190–196.Google Scholar
  8. 8.
    Tso, S.K., and Ho, P.T.: ‘Dedicated-microprocessor scheme for thyristor phase control of multiphase convertors’, IEE Proc. B, 1981, pp. 101–108.Google Scholar
  9. 9.
    Tang, P.C., Lu, S.S., and Wu, Y.C.: ‘Microprocessor-based design of a firing circuit for three-phase full-wave thyristor dual converter’, IEEE Trans., 1982, IE-29, pp. 67–73.Google Scholar

Copyright information

© D. Reidel Publishing Company 1983

Authors and Affiliations

  • S. K. Tso
    • 1
  1. 1.University of Hong KongHong Kong

Personalised recommendations