Peer-to-peer, engineer-to-engineer questions and answers from the EDABoard.com engineering community around power electronics. Click the “Read more” link and follow the entire conversation and maybe add your two cents by logging in to EDAboard.com

Driving induction motor using TRIAC – The induction motor is 230VAC. I have to drive a  230VAC  induction motor in both directions for mixing purpose. When I connected an induction bulb to check the operation of the TRIAC it works fine. But When I connect the motor means after a few revolutions, the TRIAC is burned out. Read more

MCPCB which is double sided and with plated through vias – We wish to make a 6W buck boost switchmode lighting PCB (15cm by 1.8cm) with LEDs one side and the driver electronics the other side. (everything SMD) There will also be a microcontroller to give dimming control. Read more

Suspect a TRIAC failure at neutral rail – I have a coffee grinder, works on 220V, stopped working. I opened the case and started inspecting any possible problem. The HOT line is going through couple limit switches: one at bean hopper lid and one at coffee container for safety that the machine has the hopper and container in place. So the 220V is there all the way to the motor 1st brush. The neutral line, on the other hand, is controlled by a triac which receives the pulse from pic12f508. There are two problems I encountered… Read more

Voltage control using PWM – I have a test panel in that their is an step up transformer which produces 270VAC from 230VAC. I have to use variable voltage from 170VAC TO 270VAC for my operation in a specified time. So I tried to build an automatic voltage converter to change the voltage from 170VAC TO 270VAC, based on time of operation. I tried it by using PWM output from the PIC controller with BT136, IRF540 and MOC3021 but I can’t get any output from it. Read more

Core losses in the inductor – We use Steinmetz equation to find the core losses. I have four coils from different suppliers and I want to know the core losses in each coil. Problem is that there is no information in the data sheet about the core materials and no flux density, frequency and power graphs. Read more

How to replace a relay with TRIAC? –  I want to use a TRIAC instead of relay in my circuit “just in order to occupy less space”. Relay is intended to switch 220VAC up to 8A. What is the minimum configuration for using TRIAC in my circuit? Read more

PV panel orientation vs horizon shading in winter – 99 percent of installations I see around here my panels are mounted on the roof in portrait (longest side vertical). Now in the UK winter is upon us and the sun is low in the sky. Fortunately, my roof is quite steep (52deg) so I still get reasonable output.  I now realize that if the panels were orientated in landscape (longest side horizontal) the shading diodes would work as intended as the horizon shading would blank out entire rows at once forcing the shading diodes to conduct across unproductive rows maintaining the strings output current to that of the unshaded cells. Am I missing something here or are most installations not good with horizontal horizon shading? Read more

IR2130 shut down function – I am planning to use IR2130 for driving 1/2 hp motor with g4bc20kd IGBT.  Please suggest a low-cost 3-phase bridge driver with soft turn off function. Read more

Half bridge output inductor – I made this half bridge converter. I don’t know which core material should I use MPP core or Ferrite?  Read more

How to find proximity loss – I have been given a task to calculate skin loss and proximity loss in an inductor. I have already calculated the skin loss by finding ac resistance and using it into I^2*R formula then I am able to calculate skin loss. For proximity loss, calculation work has been done for ac resistance but how to find the proximity loss using ac resistance. I think for proximity loss, simple (I^2)R formula is not valid. Read more