Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [power-electronics]

Refers to the conversion of electric power by using solid state components such as semiconductors. Can also generally apply to the field of electrical engineering which works with power electronics.

Power Electronics deals with the transformation of power to suit a needed purpose. Applications include switch-mode power supply design and motor drives.

Some assorted books on the subject:

  • Power Electronics: Converters, Applications, and Design, Mohan et al. (Considered a standard undergrad power electronics textbook in the US.)
  • Transformer and Inductor Design Handbook, McLyman
  • Switching Power Supply Design, Pressman
  • Switchmode Power Supply Handbook, Billings
  • Switching Power Supply Design and Optimization, Maniktala
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Where does electricity go after being used?

For a very long time I have been wondering, where does electricity go after being used? When I use my tablet it runs from a battery. Where does the power go?
Ethan T.
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Weird resistor with dots around it on the schematic

I was looking through the LTC4041 datasheet and saw this: The 10mOhm resistor with the two nodes really close to it - is that a "special" resistor or something? Why have they drawn it like that?
AlfroJang80
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Why do devices stop operating properly in extreme cold?

I have noticed that a lot of smart phones say that they won't operate under -4 degrees F (-20 degrees C). Can anyone explain to me what happens when the phones get cold that stops them from operating?
Sean Moriarty
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Why does the USA use 110V and UK use 230-240V?

Why does the USA use 110V and UK use 230-240V? What are the advantages? Explain me with calculation. Why do they use different frequencies like 50Hz, 60Hz? What is the reason?
user43153
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Why does power dip during a lightning storm?

If lightning were to strike power lines, wouldn't you expect it to increase the power, and hence your room lights get brighter? Why do they go dim for 1 second at a time?
PJazz
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Spacecraft Power Supply Frequency

I know that aircraft sometimes employ a 400Hz AC system to save weight on transformers, so I'd imagine that spacecraft might employ a similar technique. I'm wondering if anyone in the aerospace field can confirm 400Hz or higher frequency operation…
RYS
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Are all electrical sockets of my house in the same phase?

Most countries use AC power that is supplied to each house. This AC power is in the form of a sine wave. Suppose I have 2 electrical power sockets in two rooms that are at the opposite ends of my house. Will both the electrical sockets provide the…
Rishi Sharma
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How do I find the voltage range for an unknown DC motor?

I have a small unmarked motor with a burned out speed controller board. I'm able to figure out that the motor is a DC motor because it has two wires coming out of it and there's a rectifier on the speed controller. I want to find out what is the…
user148298
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What is Overmodulation?

The Wikipedia article is very short and doesn't explain the concept very well, and there aren't any other sites that I can find that give a simple explanation. What does it mean by 100% modulation? I understand the basic concepts behind amplitude…
Blue7
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IGBT vs. Power MOSFET for switching applications. Where to draw the line?

For lower breakdown voltages, a power MOSFET is clearly the device to go for, in view of its higher efficiency, higher commutation speed and lower price. Where should the line be drawn, upwards of which IGBTs take over as the preferable solution?…
user1975053
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Why is flyback air gap needed for energy storage?

Why do so many sources say something along the lines "since a flyback transformer stores energy, an air gap is needed"? I have seen this reasoning in textbooks and app notes. I thought air gaps cannot store energy and I thought also a flyback…
EwokNightmares
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PC ATX12VO (12V only) standard - Why does everybody say it has higher efficiency?

To my understandings, the new 12-volt only standard moves the 5V and 3.3V supplies off from the ATX power supply "box" to the motherboard. According to PC World (which is cited by Wikipedia), Gamers Nexus, and Linus Tech Tips, the new standard…
Yvon
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Voltage regulator from first principles - why is power dumped in the transistor?

I'm trying to further my understanding of electronics, so I decided to try to design a fixed voltage regulator capable of supplying an amp or so. I put this together from first principles without referring to any kind of reference on how voltage…
Polynomial
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Why an electrician wiring error could make a PC's USB shield be at 120V when it should be grounded

I almost had a serious electrical accident last week when I was trying to use an oscilloscope to test out a circuit a student had built. I had the scope plugged into a floor outlet, and the circuit board powered through a USB cable plugged into a PC…
user55515
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What does a black bar across transformer symbol designate?

What does a black bar across a transformer symbol designate? This appears in a power electronics context, and in particular in this case with substituting a DC transformer as an equivalent circuit for the guts of a DC-DC converter.
scanny
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