Junction temperature

About: Junction temperature is a research topic. Over the lifetime, 5058 publications have been published within this topic receiving 58643 citations.

Power Loss Analysis of Medium-Voltage Three-Phase Converters Using 15-kV/40-A SiC N-IGBT

Abstract: Medium-voltage (MV) silicon carbide (SiC) devices such as the 15-kV SiC N-insulated gate bipolar transistor (IGBT) have better thermal withstanding capability compared with silicon (Si)-based devices. These devices also have lower switching and conduction losses at high switching frequencies and high power levels, respectively. The maximum safe operating junction temperature for the 15-kV SiC IGBT is 175 °C. This enables high power density design of the MV converters using this device. Heat sink with forced air cooling is considered for dissipating the heat generated during converter operation. In this paper, the power loss analysis of three-phase MV converters based on 15-kV/40-A SiC N-IGBT is discussed. The converter thermal analysis is carried out based on the experimental loss data and the continuous heat-run test of the device. It is supported by analytical calculations, PLECS thermal simulations, and FEM simulations in COMSOL Multiphysics software. Hardware prototypes of the converters are developed and the experimental results support the analysis. Experimental results are given for both hard-switched grid-connected converter and soft-switched dual active bridge converter. The paper mainly focuses on the semiconductor losses in the converter.

An Improved Thermal Network Model of the IGBT Module for Wind Power Converters Considering the Effects of Base-Plate Solder Fatigue

Abstract: This paper presents an improved thermal network model of insulated-gate bipolar transistor (IGBT) module, which considers the effects of base-plate solder fatigue on the junction temperature of the said module used in wind power converters. First, the coupling thermal structure 3-D finite-element model of the IGBT module is established based on the structure and material parameters of the module used in the wind power converters of a doubly fed induction generator. The junction temperature of the module is investigated at different thermal desquamating degrees of the base-plate solder. Second, the thermal resistance parameters are determined at different desquamating degrees, and the improved thermal network model that considers the effects of the base-plate solder fatigue is established. Finally, the IGBT junction temperature results through the improved thermal network, and the 3-D FEM models are compared.

Current sharing of IGBT modules in parallel with thermal imbalance

Abstract: For large current, switching devices such as MOSFET and IGBT, often have to be connected in parallel. Due to this reason, derating and preselection of the switching devices become necessary to develop high-power converters. The current imbalance can be produced by stray inductances, device characteristic difference or asymmetric circuit. Moreover, thermal imbalance is anther important reason for current balancing. The static and transient characteristics of an IGBT vary sensitively with its junction temperature. This paper focuses on the current sharing of IGBTs in parallel with thermal imbalance. In this paper, an active gate control method which can achieve current balancing of the IGBTs in parallel with thermal imbalance, is explained and verified by experiments. This method can be applied to an actual 160kW/380V power electronics converter prototype for improving the utilization of the switching devices and enhancing system reliability.

Quasi-infinite heat source/sink

Abstract: An apparatus and method for controlling the temperature of an object, in particular a semiconductor wafer support structure in a wafer processing chamber. A gas gap is created between the two adjacent objects of different temperatures. The pressure in the gap is adjusted to control the thermal conductivity of the gas between the two structures. To have a large heat flow between the two objects so that their temperatures can be closely matched, the pressure is increased. To maintain the temperature of the object sought to be controlled regardless of the temperature of the adjacent item (heat source/sink) the pressure is reduced to a strong vacuum (acting as insulation) so that very little heat flow occurs through the gas gap. Localized control acts together with a local heat sink to precisely control the temperature of a semiconductor support structure pedestal/cathode to maintain the uniformity of the temperature of the wafer during processing to prevent wafer surface process anomalies due to variations and gradients in temperature. Heating and cooling in one structure can be controlled by using alternating gas gaps. A heating heat source/sink is placed adjacent to a cooling heat sink/source both of which face the object whose temperature is to be controlled.

Temperature monitoring of semiconductors

Abstract: A current sensor provides a voltage signal which is proportional to the average current flowing through a semiconductor device junction. This voltage signal is applied to a first analogue circuit which produces an output voltage indicative of the average power dissipated at the junction. The output of the first analogue circuit is applied to a second analogue circuit which outputs a voltage signal indicative of the temperature difference between the junction and a heat sink associated with the semiconductor device and to a third analogue circuit which outputs a voltage signal indicative of the temperature difference between the heat sink and ambient. The ambient temperature is sensed by an ambient temperature sensor which outputs a voltage signal indicative of the ambient temperature. A voltage summing circuit sums the output voltages from the second and third analogue circuits and from the ambient temperature sensor, and produces an output voltage indicative of the junction temperature.