Online Junction Temperature Extraction With Gate Voltage Under Nontrigger Current for High-Voltage Thyristor

Abstract

This letter proposes a junction temperature ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$T_{j}$</tex-math></inline-formula> ) extraction method for the high-voltage thyristors with the cathode short-circuiting structure. It has been studied that the gate voltage <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$V_{gk}$</tex-math></inline-formula> under non-trigger current is a practical temperature-sensitive electrical parameter (TSEP), which can be used for online <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$T_{j}$</tex-math></inline-formula> monitoring by calibrating the linear relationship between the gate voltage <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$V_{gk}$</tex-math></inline-formula> under non-trigger current and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$T_{j}$</tex-math></inline-formula> effect. The proposed TSEP does not affect the operating state of the thyristor and is suitable for complex operating conditions since it is extracted during OFF state. The total error in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$T_{j}$</tex-math></inline-formula> estimate obtained from the proposed TSEP is verified within ±2 °C by comparing with the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$T_{j}$</tex-math></inline-formula> obtained from the traditional gate voltage <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$V_{GK}$</tex-math></inline-formula> based TSEP during ON state.