Abstract The resonant frequency difference of piezoelectric transformers (PTs) with a classical parallel connection could worsen system performance, then the mechanical coupling of PTs was proposed to avoid the disadvantage. Experimental results showed that when the difference was relatively small, the performance of the classical parallel system and proposed mechanical coupling system was similar. However, when the difference increased, the maximum output power of a classical parallel system at a temperature rise of 20 °C reduced by 32.6% and that of mechanical coupling system reduced by 7.7%. This indicated mechanical coupling was better than classical parallel connection in improving the output power of PTs.

中文翻译：

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机械耦合减小压电变压器并联系统谐振频率差

摘要 经典并联压电变压器(PTs)的谐振频率差会导致系统性能变差，为此提出了PTs的机械耦合来避免这种缺点。实验结果表明，当差异较小时，经典并联系统和提出的机械耦合系统的性能相似。然而，当差异增大时，经典并联系统在温升 20°C 时的最大输出功率降低了 32.6%，机械耦合系统的最大输出功率降低了 7.7%。这表明机械耦合在提高 PT 的输出功率方面优于经典的并联连接。