Thyristor breakover voltage drop measurement system and method

Abstract

The invention discloses a thyristor breakover voltage drop measurement system and method. The thyristor breakover voltage drop measurement system comprises a constant current source auxiliary branch circuit, a main discharge circuit, a signal control unit and a measurement result displaying unit, wherein the constant current source auxiliary branch circuit is connected to the two ends of a thyristor to be measured in parallel, and the thyristor to be measured is both in a direct-current constant-current breakover state before or after pulse large current of the main discharge circuit flows across the thyristor to be measured. The measurement method is based on the measurement system, in order to solve the problem that the voltage of the thyristor can not be accurately measured when junction temperature is measured through a thermal sensitive parameter method, the direct-current constant current source auxiliary branch circuit is connected to the two ends of the thyristor to be measured in parallel, the thyristor to be measured is both in the direct-current constant-current breakover state before or after pulse large current of the main discharge circuit flows across the thyristor to be measured, the situation that breakover voltage drop of the thyristor to be measured is covered by blocking voltage of the two ends of the thyristor is avoided, and therefore accuracy of the breakover voltage drop measurement result of the thyristor is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of voltage measurement, and more specifically relates to a thyristor conduction voltage drop measurement system and measurement method. Background technique [0002] The thermal parameter method is a junction temperature measurement method recommended by the International Electrotechnical Commission standard IEC60747, and the thyristor voltage is generally used as the thermal parameter. [0003] In the prior art, there is a problem of inaccurate measurement of the conduction voltage drop of the thyristor in the measurement of the junction temperature by the thermal parameter method. The current of the thyristor at the turn-on moment is close to zero, and the turn-on voltage drop is a small voltage value close to the threshold voltage; since the thyristor is in the blocking state before the current starts to rise, the blocking voltage is very high, and the blocking voltage drops There is a process, the decli...

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Problems solved by technology

[0003] In the prior art, there is a problem of inaccurate measurement of the conduction voltage drop of the thyristor in the measurement of the junction temperature by the thermal parameter method

The current of the thyristor at the turn-on moment is close to zero, and the turn-on voltage drop is a small voltage value close to the threshold voltage; since the thyristor is in the blocking state before the current starts to rise, the blocking voltage is very high, and the blocking voltage drops There is a process, the decline process of the blocking voltage across the thyristor will cover up the actual small conduction voltage drop of the thyristor, so it is impossible to accurately measure the conduction voltage drop of the thyristor when the current starts to rise

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