New Approach For Measuring The Temperature Of P-N Junction

Abstract

Thermal design of power electronics systems is more significant importance to know the junction temperature , there are two methods to know the junction temperature direct and indirect, the method we introduce is the indirect which depends on TESP. We have introduced the methods of measuring the junction temperature and thermal resistance concept. The project shows a test that defines the thermal characteristic of a power diode which makes junction temperature of a specific device is known through forward voltage across the diode under constant low current , sufficient to make forward bias to the diode. The first step in this method is calibration of the power diode to define the relation between the temperature of junction and the forward voltage, we present the calibration operation and the design of hardware used in the calibration. Other part of project is application of this test, using the power diode as sensor, because its accurate , low cost, may used in high temperature measurements, which don’t need an interfacing circuit like other sensors, and its practical in some application than others. the other application to determining the junction temperature itself when it operates in its normal operation, to prevent it from failure.