基于SiC功率器件的单相APF开关损耗分析及应用技术研究

Switching Loss Analysis and Application of Single-Phase APF Based on SiC Power Device

提出一种应用于单相有源滤波器(active power filter,APF)的SiC功率器件的开关损耗模型。该模型考虑了封装和印制电路板(printed circuit board,PCB)的寄生参数与器件结电容的非线性。详细阐述四种单相APF工作状态下的建模原理,并给出了各工作状态下各时间段的开关过程分析与损耗计算方程。基于影响APF谐波补偿性能的关键因素的分析,结合APF的工作特点,提出SiC器件高开关频率兼容驱动方式与封装及电路布局优化方案。搭建基于单相APF的SiC功率器件测试实验样机,在不同电压点和电流点下进行测试,并将测试结果与估算结果进行比较。比较结果高度吻合,功率损耗误差在10%以内,验证了提出的开关损耗模型的准确性和有效性。

A switching loss model for SiC power devices applied in single-phase APF is proposed.In this model,package,PCB parasitic parameters in the circuits,and nonlinearity of device junction capacitance are considered.In this paper,modeling principles,switching process and loss calculation equations in each time period under four APF working conditions are presented.With operation characteristics of APF,this paper analyzes factors influencing harmonic compensation performance of APF and provides compatible drive pattern of SiC power devices under high switching frequency,PCB layout and packaging optimization method of main circuits.The proposed model was verified with tests on a APF prototype based on SiC power devices at different voltages and currents.Test results match well with estimation results based on the proposed model in waveforms and switching losses with maximum error less than 10%.Accuracy and effectiveness of the proposed loss model are also validated by the results.