Analysis of temperature rise for piezoelectric transformer using finite-element method
Hyun-Woo Joo1, Chang-Hwan Lee, Jong-Seok Rho
1Electromechanics Laboratory, School of Electrical Engineering and Computer Science, Seoul National University, San 56-1. Shillim-Dong, Kwanak-Gu, Seoul, Korea hwjoo74@snu.ac.kr
Summary
This study analyzes the heat and temperature field of piezoelectric transformers. An iterative method refines calculations of resonance frequency and temperature distribution, validated by experimental results.
Area of Science:
- Electrical Engineering
- Materials Science
- Thermodynamics
Background:
- Piezoelectric transformers (PTs) are crucial for power electronics.
- Understanding their thermal behavior is essential for reliable operation.
- Accurate modeling of temperature fields is needed to predict performance limitations.
Purpose of the Study:
- To analyze the heat and temperature field of a piezoelectric transformer under steady-state conditions.
- To develop an iterative method for refining thermal and resonance characteristics.
- To validate the computational model with experimental data.
Main Methods:
- Finite-element method (FEM) for resonance frequency calculation via impedance and electrical gain analysis.
- Calculation of loss distribution based on mechanical displacement and electric potential.
- Discretized heat transfer equation for temperature distribution computation.
- Iterative recalculation of losses and resonance frequency considering temperature-dependent material properties.
Main Results:
- The study determined the loss distribution and temperature distribution of the piezoelectric transformer.
- An iterative approach was employed to account for temperature-dependent material property changes.
- Recalculated resonance characteristics and steady-state temperature distributions were obtained.
Conclusions:
- The developed iterative method accurately predicts the steady-state temperature distribution and resonance characteristics of piezoelectric transformers.
- Experimental validation confirms the efficacy of the computational approach for thermal analysis.
- This research provides a foundation for optimizing the thermal management and performance of piezoelectric transformers.
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