A measurement-based method for extracting the parasitic parameters of active power electronics modules (IPEMs) is proposed. Parasitic inductances and capacitances inside the IPEM can all be extracted using this method without destroying the structure. The linearized model is derived from impedance measurement and it is valid from low frequency to frequencies as high as 100 MHz. Extracted parameters are compared to those from commercial software and the results are in good agreement. A parallel resonance method is proposed for the characterization of common-mode capacitances

Measurement-Based Method to Characterize Parasitic Parameters of the Integrated Power Electronics Modules

For analyzing reliability or short-term overload conditions of power electronic systems, it is necessary to know transient temperatures of the power semiconductors. Directly coupling thermal and circuit simulators increases the simulation time by orders of magnitude, therefore making such an approach impractical. A well-known solution to this problem is to extract thermal equivalent circuits from 3D-field simulations and to insert them directly into the circuit simulator. In this paper we discuss the poor scaling performance of this state-of-the-art approach. There is an enormous increase in simulation time if there are more than just a few chips thermally modeled. We propose a general procedure at the circuit simulator solver level to increase the calculation speed of such a coupled simulation significantly.

Computationally Efficient Integration of Complex Thernal Multi-Chip Power Module Models into Circuit Simulators

Integrated power electronics modules (IPEMs) represent an innovative typology of power electronics assemblies able to guarantee several advantages such as increasing of power density, better management of the thermal flows, and a significant reduction of the package sizes. Their characteristics make them suitable for applications like motor drives or power conditioning. IPEM usage in emerging fields like hybrid automotive traction and electric generation from renewable energy sources is continuously increasing. In this paper, we describe the implementation of a devised flow to generate the layer-based electrothermal PSpice model of an IPEM and the simulation flow of the model. The proposed modeling methodology allows reducing an electrothermal multidomain problem to an electrical single one. The general PSpice-like nature of the proposed model makes it suitable for a wide range of simulation frameworks where the integration of heterogeneous multiphysics models could be a difficult task. The outlining of both electrical and thermal PSpice layers is discussed, and the implementation into the final model, by the assistance of custom electronic-design-automation flow, is presented. Moreover, we describe the validation procedure of the proposed approach, and the results are compared with the ones obtained by a commercial finite-element-based package used as a benchmark. Two simulation approaches related to specific conversion systems, and related issues, are presented and discussed.

Electrothermal PSpice Modeling and Simulation of Power Modules

∗Power semiconductors can be modeled as a thermal network of resistors and capacitors. The thermal boundary condition of such a model is typically defined as the heat sink surface temperature, which is assumed to be constant. In reality, the heat sink surface temperature underneath the power module is not exactly known. In this paper we show how to set up a thermal model of the heat sink in form of a RC thermal equivalent network that can be directly embedded in any circuit simulator. The proposed thermal heat sink model takes into account convection cooling, thermal hotspots on the heat sink base plate, thermal time constants of the heat sink, and thermal coupling between different power modules mounted onto the heat sink. Experimental results are given and show high accuracy of the heat sink model with temperature errors below 10%.

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A Thermal Model of a Forced-Cooled Heat Sink for Transient Temperature Calculations Employing a Circuit Simulator

Investigation of High-density Integrated Solution for AC/DC Conversion of a Distributed Power System

The need for integrated analysis and design tools is becoming more evident, especially when integrated power electronics module (IPEM) is concerned. The whole procedure of developing IPEM needs the support from integrated tools. In this paper, a set of IPEM models has been developed. This includes a 3D solid model by I-DEAS, parasitic model by Maxwell, thermal model by FLOTHERM and electrical model by Saber. The exchange of geometry information among these models has been achieved. Furthermore, based on these models, this paper explores the tradeoff between minimizing parasitics and improving thermal performance.

Yingxiang Wu

Papers

Integrated electrical and thermal modeling and analysis of IPEMs