Hi all, Mechanical engineer needing some electrical help. So electrically piezo actuators are modeled as capacitors. Power(P) = C*U*dU/dt, where U equals voltage. I'm seeing several sites like here: http://www.piezo.ws/piezoelectric_actuator_tutorial/Piezo_Design_part3.php They say for sinusoidal operation Pavg ≈ C*U^2*f and Pmax ≈ ∏*C*U^2*f (assuming you start from 0 Volts). So my questions are: 1. How can you substitute U*f for dU/dt to get average power from the main power equation? 2. How is Pmax ≈ ∏*Pavg? 3. What does average power mean for a cycling device? Wouldn't RMS make more sense? Hopefully someone with some familiarity and/or better math skills can help me out. Thanks!