I hosted a webinar on April 14, 2023 on

"How to use an Arduino to measure phase between voltage and current in an ultrasonic transducer"

You can watch the recording on my YouTube Channel here: 

https://youtu.be/2_-4a16gJz4

Here is a link to the presentation notes.

Topics

In this webinar recording, I used a simple circuit to measure the phase angle between voltage and current by converting it to a DC signal. This signal can be read by an Arduino or other microcontroller.

This was accomplished by feeding the voltage and current signals to comparators, and then creating an averaging circuit with a RC filter.

I integrated all of this with an Arduino and I was able to minimize the phase and drive a piezoelectric/ultrasonic mesh atomizer at it's resonance frequency

Video detailed outline:

• 0:00 - Introduction to webinar topic
• 1:00 - Outline - (Part 1 Theory, Part 2 Practice)
• 2:00 - Demonstration of phase tracking of an ultrasonic mesh atomizer
• 2:45 - Introduction to Ultrasonic Advisors
• 4:19 - Why measure phase?
• 11:51 - Circuit to measure phase (convert phase to DC voltage)
• 17:10 - LT spice simulation demonstration of circuit function
• 20:26 - Block diagram of ultrasonic driver with phase feedback
• 21:26 - Generating sine wave using AD9833/AD9837
• 23:00 - Driving amplifier
• 25:15 - Transformer
• 25:40 - How to probe voltage and current and measure phase angle
• 28:37 - Impedance response of ultrasonic mesh atomizer
• 29:50 - Oscilloscope view of voltage and current with frequency sweep
• 31:38 - DC voltage measurement of phase during frequency sweep
• 33:12 - Arduino measurement of DC phase voltage during frequency sweep
• 34:12 - Intro to Arduino code for frequency tracking
• 34:58 - Arduino phase tracking in action
• 36:50 - Detailed Arduino code explanation
• 38:17 - Pictures of Arduino and circuit
• 39:51 - Schematic of actual circuit

***Announcement***

My next webinar will be 11AM ET - May 19, 2023  "Implementing dual feedback loops for constant current and constant phase for ultrasonic transducer drive"

Here is the link to sign up for the upcoming webinar: https://www.ultrasonicadvisors.com/monthly-ultrasonic-webinar