Page 203 - Power Electronic Control in Electrical Systems

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Power electronic control in electrical systems 191

Fig. 6.15 Ideal transient-free switching waveforms. (a) switching on; and (b) switching off.

Fig. 6.16 Circuit for analysis of transient-free switching.

dv
i ˆ C ˆ ^ vo 0 C cos (o 0 t ‡ a) (6:9)
dt
where a ˆ p/2. Now o 0 C ˆ B c is the fundamental-frequency susceptance of the
capacitor, and X c ˆ 1/B c its reactance, so that with a ˆ p/2
^
i ˆ ^ vB c sin (o 0 t) ˆ‡i AC sin (o 0 t) (6:10)
^
^
where i AC is the peak value of the AC current, i AC ˆ ^ vB C ˆ ^ v/X C .