换能器谐振
当施加的电压与电流同相（即相位角为零）时，换能器（包括任何附带的谐振部件，即叠堆）处于谐振状态。
对于压电换能器中的任何指定模态（例如轴向模态），都存在两个相邻的谐振，它们取决于陶瓷与换能器机械部件之间的相互作用。这两个谐振称为短路谐振和开路谐振。短路谐振略低于开路谐振。这两个谐振之间的频率差会随陶瓷总电容的增大而增大，随叠堆相对储能的增大而减小。
设计人员可根据所需的谐振特性和电源特性，选择在串联谐振或并联谐振处或其附近工作。
Transducer resonance
A transducer (including any attached resonant components -- i.e., the stack) is resonant when the applied voltage and current are in phase (i.e., zero phase angle).
For any specified mode (e.g., the axial mode) in a piezoelectric transducer, there are two adjacent resonances that depend on the interaction of the ceramics with the mechanical components of the transducer. These resonances are called short circuit resonance and open circuit resonance. Short circuit resonance falls somewhat below open circuit resonance. The frequency difference between these two resonances will increase as the total ceramic capacitance increases and will decrease as the relative energy storage of the stack increases.
The designer may choose to operate at or near either series or parallel resonance, depending on the resonance characteristics and power supply characteristics that he desires.