Electronic temperature sensor for measuring the junction temperature of an electronic power switch during operation, and method for measuring the temperature of the junction by this electronic sensor

An electronic temperature sensor for measuring the junction temperature of a controlled electronic power switch of an electronic switching cell of a static converter:

• comprising:
• an injection source of a calibrated measurement current and a differential voltage measurement amplifier,
• the injection source of a calibrated measurement current having at least one injection and output terminal and being configured to deliver a first calibrated measurement output current at a first injection and output terminal from among the at least one output terminal, the first output terminal being designed to be connected to an upstream power terminal of the junction of the electronic switch whose temperature is being measured,
• the differential voltage amplifier having a first differential amplifier input terminal and a second differential amplifier input terminal for a differential voltage signal,
• a first series connection element for protecting against a high voltage having a first element terminal connected to the first differential input terminal of the differential voltage amplifier and a second first element terminal connected to the upstream power terminal of the semiconductor junction of the electronic switch whose temperature is measured,
• a second series connection element protecting against a high voltage, having a third second element terminal connected to the second differential input terminal of the differential voltage amplifier, and a fourth second element terminal connected to the downstream power terminal of the semiconductor junction of the electronic switch whose temperature is being measured,
• the first and second series connection elements having essentially identical electrical characteristics and being comprised in the set formed by resistances and high-voltage rapid diodes.