压电高压能源变换器工作频率特性

Operating Frequency Characteristics of Piezoelectric High-Voltage Power Supply Converter

为研究压电变压器在高压能源变换器中充电过程的工作频率特性,利用基波分析法得出变换器输出电路的等效模型.分析变换器在充电过程中的频率特性,得出输出的等效电容随工作周期的增加而增加,等效电阻随工作周期迅速增加并达到最大,然后开始缓慢减小并趋于稳定值.整个变换器充电过程中,变换器的工作频率随着工作周期的增加而减小,但变化较小,9万个工作周期(约合1.1s)内,工作频率变化约为0.8kHz.

The operating frequency characteristics of high-voltage power supply converter based on piezoelectric transformer（PT） is researched.The analysis of fundamental wave was used to get the equivalent model of converter output circuit and then the frequency characteristics of converter were investigated in the process of charging.It is found that the output equivalent capacitance increases with the increase of the operating periods.The equivalent resistance prompts rapidly with the increase of operating periods and achieves the maximum,then descends slowly and tends to a steady-state.In the whole process of the converter charging,the converter operating frequency descends with the increment of operating period,but the change is small,the operating frequency is only changed about 0.8 kHz in 90 000 operating periods（about 1.1 socend）.