Method and system for estimating junction temperature of power semiconductor device of power module

A system for estimating a junction temperature of a power semiconductor device of a power module and controlling the power module, the power module including a first power semiconductor device disposed adjacent to a heat sink for cooling and having a temperature sensor, and a second power semiconductor device disposed adjacent to the first power semiconductor device and having no temperature sensor, and the system comprising:

• a memory configured to store a predetermined power loss computational formula of each of the first and second power semiconductor devices using a plurality of parameters as variables and a thermal resistance of each of the first and second power semiconductor devices;
• and
• a processor configured to determine a junction temperature of the second power semiconductor device based on information stored in the memory and a sensing temperature of the temperature sensor,
• wherein the processor is configured to:
• receive the plurality of parameters related to an operation of the power module to calculate the power loss of the first power semiconductor device, and compute a junction temperature prediction value of the first power semiconductor device based on the power loss and the thermal resistance of the first power semiconductor device,
• receive the plurality of parameters related to the operation of the power module to calculate the power loss of the second power semiconductor device, and compute a junction temperature prediction value of the second power semiconductor device based on the power loss and the thermal resistance of the first power semiconductor device,
• compute a temperature prediction value of the heat sink by subtracting the junction temperature prediction value of the first power semiconductor device from the sensing temperature sensed by the temperature sensor provided in the first power semiconductor device,
• determine the junction temperature of the second power semiconductor device by adding the temperature prediction value of the heat sink to the junction temperature prediction value of the second power semiconductor device;
• and
• stop an operation of the power module in response to determining that the determined junction temperature of the second power semiconductor device is greater than a preset reference value.