# Piezo-electric actuator’s resonance frequency

1. Dec 22, 2008

### Mestik

Hi all,

Sorry for any mistakes but this is my first time I write a post in English.

I would like someone to explain me exactly what is the resonance frequency in a piezo-electric actuator. Also give me any link for more information.

Does the frequency of the controller play any role because I would like to keep it and change only the piezo-electric actuators?

Thanks for any help.

2. Dec 22, 2008

### ank_gl

resonance frequency is the nemesis frequency for all the systems. lets suppose that you are operating the actuator 100 times a second, & its resonant frequency also happens to be so, the amplitude ll go berserk.

For your second question, make sure you dont end up with an actuator with its resonant frequency close to the controller frequency

3. Dec 23, 2008

### Mestik

So the actuator has the maximum displacement when operates with its resonant frequency.

What determines that the actuator operates with this frequency? Is the maximum drive voltage?

4. Dec 23, 2008

### ank_gl

not maximum, it is infinite, well thats the theory part. In actual practice, damping isn't negligible, so there is a maximum. I would recommend you read a book about vibrations.

The input controller determines the frequency you want to operate on. eg, you can have the actuator operate 100 times a second(100Hz) or 1000 times a second(1000Hz) etc. Input voltage would vary the amplitude, not the frequency. More voltage, more the energy, but still the time to dissipate it is same(time depends on the frequency), so higher is the amplitude of vibration.

Still, reading a book would be most beneficial to you.

5. Dec 24, 2008

### Redbelly98

Staff Emeritus
The piezo will operate at the same frequency as the driver. It is desired (in most applications) that this is less than the resonance frequency, to avoid the large amplitude vibrations that ank_gl mentioned.