Method for estimating power system health

A power conversion system including:

• at least one semiconductor power electronic switch, the switch having a gate driver;
• and
• a processor connected to the switch,
• wherein the processor is configured to:
• estimate a junction temperature of the switch;
• and
• count a number of temperature cycles based on the junction temperature, and
• wherein the gate driver includes one or more parameter measuring modules, and when the number of temperature cycles reaches a predetermined number of cycles, the one or more parameter measuring modules measure one or more respective parameters selected from the group consisting of:
• a rate of change of voltage across the switch;
• a rate of change of current through the switch;
• a charge present on a gate of the switch;
• a peak overshoot voltage across the switch;
• and a peak overshoot or reverse recovery current through the switch,
• wherein the processor is further configured to estimate the health of the switch based on the measured one or more parameters,
• estimating the health of the switch includes identifying changes in the measured one or more parameters as a function of temperature cycles, and
• an amount of change exceeding a threshold at higher temperature cycles indicates that the switch is unhealthy.

A gate driver for a semiconductor electronic power switch, the gate driver being suitable to be installed in a power conversion system, the gate driver comprising:

• an embedded processor configured to:
• estimate a junction temperature of the switch;
• count a number of temperature cycles based on the junction temperature;
• when the number of temperature cycles reaches a predetermined number of cycles, execute one or more parameter measuring modules for measuring one or more respective parameters selected from the group consisting of:
• a rate of change of voltage across the switch;
• a rate of change of current through the switch;
• a charge present on a gate of the switch;
• a peak overshoot voltage across the switch;
• and a peak overshoot or reverse recovery current through the switch;
• and
• estimate the health of the switch based upon the measured one or more parameters, wherein
• estimating the health of the switch includes identifying changes in the measured one or more parameters as a function of temperature cycles, and
• an amount of change exceeding a threshold at higher temperature cycles indicates that the switch is unhealthy.