Title :
New synchronization method for thyristor power converters to weak AC-systems
Author :
Weidenbrüg, Richard ; Dawson, Francis P. ; Bonert, Richard
Author_Institution :
Inst. for Power Electron. & Electr. Drives, Aachen Univ. of Technol., Germany
fDate :
10/1/1993 12:00:00 AM
Abstract :
An improved approach to obtaining good zero-voltage-crossing signals is presented. These signals are subsequently used as synchronization signals for a phase-controlled thyristor power converter. Detection of accurate zero crossings is possible even when there are large frequency changes, sudden load changes, or large commutation overlap angles. The improved accuracy in the integrity of the zero crossing is obtained by reconstructing a voltage representing the AC source voltage. This voltage is determined from the distorted thyristor converter input voltage, the converter input current, and an online identification of the source impedance using a microcontroller-based adaptive algorithm. The improvement provided by the new zero crossing detection scheme is verified experimentally
Keywords :
commutation; electric impedance; phase control; power convertors; synchronisation; thyristor applications; AC source voltage; commutation overlap angles; converter input current; distorted thyristor converter input voltage; microcontroller-based adaptive algorithm; online identification; phase-controlled thyristor power converter; source impedance; synchronization method; thyristor power converters; weak AC-systems; zero-voltage-crossing signals; Adaptive algorithm; Bridge circuits; Circuit testing; Delay; Frequency synchronization; Impedance; Power electronics; Pulse circuits; Thyristors; Voltage;
Journal_Title :
Industrial Electronics, IEEE Transactions on
