engineer1000
Advanced Member level 4
I have an impedance plot of a ceramic ultrasonic transducer, I am trying to run it at the third harmonic, the impedance plot says it should be 135khz.
I am using a half bridge switching through a transformer and then using a choke and the static capacitance of the transducer as the resonant circuit.
Calculating L is L= 1/((2��f)2) C
I am using an adjustable choke butno matter what value the choke is I can’t get the transducer to resonate at 135khz. It resonates at 131.7kHz.
I can tell this by hooking a scope across the transducer looking at the sine wave fed in to the transdcuer and finding the highest amplitude wave form .
This is at 131.7KHz.
What I want to know is why is n’t it at 135khz?
I am using a half bridge switching through a transformer and then using a choke and the static capacitance of the transducer as the resonant circuit.
Calculating L is L= 1/((2��f)2) C
I am using an adjustable choke butno matter what value the choke is I can’t get the transducer to resonate at 135khz. It resonates at 131.7kHz.
I can tell this by hooking a scope across the transducer looking at the sine wave fed in to the transdcuer and finding the highest amplitude wave form .
This is at 131.7KHz.
What I want to know is why is n’t it at 135khz?