192.6.2. Static V-I Characteristics of a Thyristor:An elementary circuit diagram, for obtaining static. V-I characteristics,, of a thyristor is shown in Fig. 2.9(a). The anode and cathode are connected to main source through the load. The gate and,cathode are fed from a source Es which provides positive gate current from. Gate to cathode.Fig.2.9(b) shows static V-I charact. of a thyristor. Here Va is the anode voltage across, thyristor terminals A, K and la is the anode current. Typical SCR characteristic shown in Fig. 2.7(b) reveals that a thyristor has three -basic modes of operation namely reverse blocking mode, forward blocking (off-state) mode and forward conduction (on-state) mode.Fig.2.9 2.6 .3 THYRISTOR TURN-ON METHODSWith anode positive with respect to cathode, a thyristor can be turned on by anyone of the following techniques:V-I