SCR triggering-Theory vs Practical

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textu123

Joined Jan 10, 2012
1
This is about my electoric hobby.Thyristor may be old-fashioned device,and I can't find good articles about it on the web of my country.
Refer to the figure of 'Phase-shifted signal triggers SCR into conduction.' from vol_3/chpt_7/5.html

In the figure I mentioned,I attempted to adjust firing angles(infomation:single phase,half-wave rectification:AC Power eff 20V,60Hz,Load 50 ohms,SCR SF30F13). So,approximated Anode to Kathode as an infinite resistance and as(Gate to Kathode resistance)>>(variable ressistance ) . I also presumed that the angle of voltage E is always 0degrees.
This estimation caused great gap between expressions and practical.

I thought out 'Harmonics' 'remain voltage in C' 'firing distorts sine-wave' 'added harmonics on Voltage E' 'extended on-time to msec order unusually'


Please tell me Major causes of this difference.
 
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