A Novel Method of Stabilizing the Vibration Velocity at the End of Piezoelectric Transducers - Advanced Research on Computer Education, Simulation and Modeling - page 45

− 4 − 6

τ = 5 × 10 s τ = 5 × 10 s

(a) Frequency tracking (b) ,

A B

− 4 − 6 − 3 − 6

(c)

τ = 5 × 10 s

,

τ = 1 × 10 s

(d)

τ = 2 . 5 × 10 s

,

τ = 5 × 10 s

A B A B

Fig. 7. Overshoot of the voltage and current when the transducer being unload

voltage increase is faster (or A τ is smaller). However, speed of voltage decrease( )

τ

B

doesn't affect the regulation process at all.
As shown in Figure 7, when load decreases, the slower the voltage increases, the
smaller the overshoot of incentive voltage will be. The overshoot v and the voltage
current both depend on the speed of voltage decrease (or τ ). The faster the voltage

B

decreases (or τ is smaller), the smaller overshoot of the current will be.

B

6 Conclusions

The asymmetric automatic steady speed control method proposed in this paper offer a
solution to protect devices by reasonably setting up/down speed of driven voltage and
frequency tracking speed. The faster the speed of the voltage decreases, the smaller
overshoot is. By comparison with the traditional method, the transducer controlled
using the proposed method will be subjected to a smaller overshoot of voltage and
current, no matter how the load changes in the process.

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