Effect of the Trigger Circuit on Delay Characteristics of a Triggered Vacuum Switch With a Six-Gap Rod Electrode System

Abstract

Nowadays, the triggered vacuum switch (TVS) is widely used in electromagnetic launcher systems. An important performance of TVS with the six-gap rod electrode system, which has long operating life and maximal switching capacity, has been used in experimental research. The delay time is an important feature of TVS. Therefore, this paper focuses on the effect of trigger circuit and trigger current on the delay characteristics of the TVS. The result shows that, in an indirect trigger circuit, by changing the parameters of the pulse transformer and capacitance <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$C\hbox{1}$</tex></formula> , the trigger current can be increased, and the delay time can be decreased simultaneously. In a freewheeling circuit, the rate of the trigger current rise can reach 150 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\hbox{A}/\mu\hbox{s}$</tex></formula> , and the delay time is 2–4 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu\hbox{s}$</tex></formula> . Yet, in the trigger circuit, in which the capacitor <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$C\hbox{2}$</tex></formula> is in parallel between the second side of the pulse transformer and the trigger electrode, the rate of the trigger current rise can reach 20 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$ \hbox{kA}/\mu\hbox{s}$</tex></formula> , and the delay time is 2 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu\hbox{s}$ </tex></formula> . In a direct trigger circuit without the pulse transformer, the rate of the trigger current rise is greater than 4 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\hbox{kA}/\mu\hbox{s}$</tex></formula> , and the delay time shortens to 500 ns, which is the minimum. The delay time can be shortened obviously by changing the trigger circuit.