WEEK 2

WEEK 2

Activity : 
Continue study on operation of an ideal Marx Generator.

Objective : 

• To understand more about circuit diagram.

Content:

Multi Stage Marx Impulse Circuit

Due to the difficulties faced in very high voltage switching of the spark gap, increase in circuit element size, requirement of high direct current voltage to charge capacitor and difficulties in corona discharge suppression from the structures during charging period the extension of the single stage to multistage impulse generator is made.

A multistage generator is developed by cascading smaller single stage generator to generate high magnitude of output voltage. The primary requirement is to charge capacitors through the rectifier circuit and when all the capacitor reaches to the fully charged state then spark gaps are allowed to break down causing the capacitors to add in series. As a result the nominal output voltage is equal to the input voltage multiplied by the number of stages in the impulse generator circuit. At first, n capacitors are charged in parallel to a voltage (V) by a high voltage DC power supply through the resistors. The spark gaps used as switches have the voltage V across them, but the gaps have a breakdown voltage greater than V, so they all behave as open circuits while the capacitors charge. The last gap isolates the output of the generator from the load; without that gap, the load would prevent the capacitors from charging. To create the output pulse, the first spark gap is caused to break down (triggered); the breakdown effectively shorts the gap, placing the first two capacitors in series, applying a voltage of about 2V across the second spark gap. 

Consequently, the second gap breaks down to add the third capacitor to the stack, and the process continues to sequentially break down all of the gaps. The last gap connects the output of the series stack of capacitors to the load. Ideally, the output voltage will be nV, the number of capacitors times the charging voltage, but in practice the value is less.

CONCLUSION

Looking fot the multiple stage marx generator.