Power Electronics Top Talks in October on EDABoard.com forums

(editor’s note: Intrigued by the problem? Have a question or another solution? Then click the “Read more” link and follow the conversation on EDAboard.com or log in to EDAboard and participate in the power electronics forum threads.)

Switch design by using solid devices – I want to know how to design a solid static switch to replace my manual switch. The switch rating is 230 V, 6 A.  I need to change the condition of the switch by pressing a single button. Can it be done by using a thyristor or MOSFET or IGBT? Read more

Tone control circuit critique – Does does this circuit look ok? I need it to control the tone of my speakers. The signal to this circuit would come from my laptop. Read more

3 level NPC inverter with UCC21521 – I have some problems with a 3-level NPC inverter topology. When I tried the same circuit with 2-level full bridge, my results were excellent but when I tried with 3-level NPC…nothing. I amPWMng spwm for driving and a UCC21521 dual high/high, low/low, half bridge driver for driving. My mosfet is a SCT3160KL. I think the main problem may be the ground level. Read more

 

Looking full H-bridge driver – I need a high current, full H-bridge driver for MOSFET in bridge. Which controller would you recommend? Read more

Solar and grid current and voltage monitoring – I want to monitor a 150VDC/4KW and current for a solar panel, 230 VAC/3KW voltage and current for a grid. I’ll use a microcontroller to display these parameters. How do I monitor the DC voltage and current? Also, how do I monitor the AC voltage and current? Read more

230 AC to 6 V, 100MA converter without transformer – I am seeking a  cheap and simple AC to AC converter for a 230 VAC  to 6 VAC with up to 1 A current with a safety cicircuit. The purpose is to make a digital voltmeter. Read more

Powering up with a large capacitor in parallel –  I have a board (Vbus is 160V) with a few amplifiers on it that sends short bursts to a load. The peak absorption is about 20A for 5ms (every 1s). Since I want to parallel some of them, I will have peaks of ~200A. I want to perform some test by paralleling 100mF, but the problem is that I need to separately power the board, charge the capacitor and then close a switch that connects the capacitor in parallel. I am pretty sure this is a common situation with large capacitor: do you know if there is some commercial chip that acts as a controller in such a situation? I would like this to be automatic. Read more

Reading schematic values – I saw a schematic diagram of a power supply and it doesn’t seem to use a unit for its capacitance. I can only see 0.01/2K. Is it right if I consider it as 10nF? Any standard on this? What does this /2K mean? I also saw resistor values 10/3, 47K/1 18K/3. What does this slash mean? Read more

Component selection of series resonant converter – How do we size the inductor and capacitor of series resonant full brigde converter? For a specific resonant frequency, there are lots of capacitor-inductor combinations with the same resonant frequency. Read more

DSP sine wave inverter error message – The board below uses a dsPIC30F2010. It has two mode inverters and UPS modes. I have made a lot of inverters with this board but now I am experiencing an error message on the LCD “No feedback loop “.  I know these problems arise from transformer sensing section but my transformer is working well. Read more