| 摘要 |
PROBLEM TO BE SOLVED: To provide a piezoelectric drive circuit of a zero voltage switching system, which is suitable for use in a power converter of a switching system.SOLUTION: Input direct-current voltage is received by a half-bridge drive circuit, and an upper arm switch set and a lower arm switch set are switched by half-bridge driving to convert the input direct-current voltage into alternating-current voltage and provide that to a piezoelectric element. The alternating-current voltage drives and actuates a load through the piezoelectric element. The half-bridge drive circuit and the piezoelectric element are electrically connected to a shunt circuit, and used for zero voltage switching. Namely, when both of the upper arm switch set and the lower arm switch set are turned off, by resonating with a parasitic capacitor, the upper arm switch set and the lower arm switch set are made to perform zero voltage switching. Therefore, an effect of zero voltage switching can be materialized, within a very wide frequency range and under load fluctuations of a wide range. |
