Vibration energy harvesting by piezoelectric sensors: neutralization of capacitance loading

[@yingqiangli6026]

The best lecture on piezo energy harvesting!

[@sambenyaakov]

Thanks

[@stephenweiss3119]

I always enjoy your lectures Sam Ben-Yaakov. We patented a very similar design in 2005 (US6947714B2) that stored a charge until a threshold voltage was achieved at which point the stored energy was released to power the RF transmitter portion of the circuit that broadcast a tone (~1kHz) modulated at 27MHz.

[@sambenyaakov]

Hi Stephen, thanks for reference to interesting patent.

[@stephenweiss3119]

@@sambenyaakov My pleasure, Sam Ben-Yaakov. Thanks for posting all your informative and enjoyable lectures!

[@UnbornWarrior123]

Thanks a lot for your lectures. I have few questions. Your patience in making this video inspires me to hope for answers. 1. Can you show proper circuit diagram at 14:46. It is confusing to see gate terminals of mosfets/switches are fed with current coming from pizo generator. If gate terminals are indeed connected to pizo electric output, how its operation will be? 2. What is the power application range for pizo circuits? Do they need power mosfets or signal level mosfets for implementation. 3. To measure currents at levels of micro amperes which kind of oscilloscope you have used? Can you suggest good reading to learn about requirements of oscilloscopes to measure various current and voltage levels and various frequencies. 4. at 21:25, why you were using bjts as opposed to converter at 14:46. Which factor determines to use BJT/MOSFET. Further. paper at 21:25 is published in 2012 a time where mosfets are highly popular and almost replaced BJTs. 5. How did you manage to design/create IC at 24:25 such a very tiny 1mmX1mm. It has created in your lab or outsourced to some industry? Thanks in advance to your answers. Regards, Venkata.

[@sambenyaakov]

Hi Venkata, would you please post the questions at the LinkedIn group www.linkedin.com/groups/13606756 so members of the group can benefit.Please add a link to video. Thanks

[@GregtheGrey6969]

So duality creates piezoelectric. We are the free energy we seek. Sports, politics, religion...all energy harvesting devices.

[@sambenyaakov]

😊

[@khouloudhamza4131]

Thank you for the lecture. At 17:46 you show the waveforms of the resonant rectifier circuit. Can you please explain more why the current ires activate just in the minimum and maximum? and how we can said that there's resonant if still thers's phase shift between input current i(in) and input voltage V(in) ? Thanks in advance for your answers.

[@sambenyaakov]

This is a rectifier with capacitive filter. The current will flow when the input reaches the capacitor's voltage.

[@khouloudhamza4131]

@@sambenyaakov Thanks for your response. And what about the resonance ???

[@jacksmith-se8lo]

thank you for the lecture ^^ I would like to ask how select the value of the inductance for a parallel sshi circuit?

[@sambenyaakov]

Is should resonate with the piezoelectric element at its mechanical resonant

[@LightningHelix101]

Very cool tech. Curious how well they can make a crystal that resonates to sounds waves with a large pizo transfer.

[@robson6285]

Haa great great great, a new real-e-videolesson!

[@plemli]

Thanks, again an interesting topic. Pardon my late evening musing here: one would usually associate piezo-electric elements with much higher frequencies - tens of kHz up to MHz . Of course mechanical vibrations at such frequencies are uncommon so there is not much to be harvested. But if these vibrations are present and undesirable, this might be a 'green' way to actively damp them.

[@emmanuelugwu6586]

How can I determine the correct value of my filter capacitor's capacitance and the voltage that can be used after voltage rectification? What equation can I use or should I just try many capacitors until I find the one that suits my project?

[@sambenyaakov]

You can find the formula in many text books and I would guess by googling it, e/g ece.iiita.ac.in/video/EMI-Manual-Practical-2.pdf

[@jacksmith-se8lo]

how can the circuit behave in the case of supercapacitor? how can we model a supercapacitor as a resistor and how to bring it to be an optimum load?

[@sambenyaakov]

I am not sure I follow your question.

[@64etto]

Di recente ho fatto domanda al istituti di ricerca perchè non utilizzare i cristalli piezoelettrici o piezomeccanici per regolare con una piccola tensione le diottrie le messa a fuoco e la struttura di prismi ottici, visto che per regolare la collimazione o messa a fuoco della lente di plastica del laser del lettore cd rom, cd audio, dvd, utilizza un solenoide "quanta energia risparmia un cristallo piezoelettrico da un solenoide"?

[@sambenyaakov]

See products of Nanomotion

[@64etto]

@@sambenyaakov I don't see it, but I encourage development and in any case they are already looking for at least the Italian CNR

[@Ap-zq7lb]

Prof may you suggest me few topics for research on converters related to high voltage given having good knowledge of microcontroller, power electronics. Suggestions will be helpful. Thank you.

[@sambenyaakov]

Is this for a graduate studies research like a thesis?Please respond to [e-mail]

[@Ap-zq7lb]

@@sambenyaakov working in the field of electronics.

[@nurnadiawasri5996]

hi sir, im very interested in this topic because I'm doing my final year project. may i know how you determine the parameters for the piezo element? may i know how to contact you?

[@sambenyaakov]

You can write to me at [e-mail]