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.
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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?
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what the best way to calculate Rg gate driver for Mosfet
I need to drive a MOSFET IPW90R120C3 from Infineon
here the Specification of MOSFET
VDS @ TJ=25°C 900 V
Rdson @ TJ=25°C : 0.12ohm
Qg = 270nC
Specification of ...
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Torque-Speed Equation for Induction Motor
I am looking for the Torque-speed equation on an Induction Motor that is used to draw the curve.
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Regarding Ferrite Bead
What is a ferrite bead? How is it different from an inductor? How is it rated? What are its important parameters? What allows me to chose between an inductor or ferrite bead to filter out frequencies ...
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Burning a Power MOSFET
We are doing battery heat testing and want to be able to vary the current in the circuit to different test points up to 100A. Our circuit schematic is attached. The MOSFET is IXFN360N10T. We attached ...
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Full Bridge VSI problem
The above problem was asked in GATE(Graduate Aptitude Test in Engg) 2015 in India.
I have no idea where to start so I can't show my attempt. But through google, I got solution by 2 different coaching ...
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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 ...
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What are the adavantages of neutral vs. isolated grounding?
While studying "Neutral grounding" I've come to know that advantage of neutral grounding is
Voltage to ground are limited to phase voltage.
The high Voltages due to arching faults or transient line ...
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How to define working voltage class net to calculte the creepage?
I work of a project of single phase PFC converter and I need to define the working voltage to each each NET of Schematic to calculate creepage distance.
I have a question about the low voltage of NET ...
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Why is my PWM efficiency about 50%?
I'm using a BTS7960 module with an Arduino to adjust the voltage for my DC motor.
When I check efficiency there is a problem. PWM efficiency is supposedly about 90% but mine is only about 50%.
I ...
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Capacitor Voltage Rating
How to find the voltage rating of a capacitor after knowing the capacitance value.
Example,
For a power supply, If the input voltage is 60V and output is 5V. The input capacitor(C1) value is 100uf ...
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How can I test a TLP582 optocoupler?
Have few of these components (TLP582) and I need to design a test circuit to test its functionality.
Datasheet of TLP582
I have no idea how to make a circuit for this.
What should I be testing in an ...
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SPWM vs 6-step PWM vs SVMPWM
While learning 3-Phase scalar control of ACIM using STM32F407 MCU I could not clearly understand the diffrence between the following terms:
1. SPWM
2. 6-step PWM
3. SVMPWM
How do they differ from ...
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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 ...
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What does it mean that a resistor has value of 56E?
I found on one schematic that has resistor with value 56E.
I don't know what does that mean.
Can you give me some information, please.
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Why do we want higher power factor in ac motors?
Here is a simplified 3P electric motor below:
This motor is simply combined of three coils facing toward to the rotator (in the center) 120 degree apart to each other.
The user wants his rotator to ...
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How is the gate trigger resistor value calculated for a triac
As per the application notes of bta08-600cw, to control a three phase induction motor, for triggering the triac gate, the value of resistor is shown as 510 ohm. How is this value arrived at? What ...
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Can this push pull oscillator improved for experimental realization?
I am using the following push pull oscillator circuit is extracted from this Application Note for implementation of a wireless charging system. In simulations, it's efficiency is above above 85% when ...
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How could the Gate-Source potential difference be neglected?
I’ve been reading the book
Electronic Principles by Malvino
In the Voltage-Divider bias section of JFET, if gate current is negligible then how did Gate Voltage attain a negative value, given Vdd ...
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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?
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What kind of hardware implements Fourier transform?
I looked around online but I found nothing relevant. It is very difficult for an electronic device to decompose a signal in different frequencies.
How this is done at the bare metal level?
Any ...
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Which method or component is best to regulate 42 to 3.3 V?
I am using a 36 V battey pack (10s 2.5 A each cell 3.6V.) Its maximum voltage is 42 V. I am using a STM32 microcontroller whose input is 3.3 V.
I am designing a PCB in which the power supply is drawn ...
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Will a battery short out when the terminals are directly connected together or will internal resistance save it?
I intended to make a simple electromagnet, then I saw this video where the user is connecting wires together with no resistance at all. I was wondering why it doesn't short out and make the battery ...
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AC MOSFET switching without any diodes? (Low-cost AC solid-state relay with MOSFETs)
Is it possible to switch an AC load using two MOSFETs in anti-series as in the picture below?
In this mode, each MOSFET is on during one half of the wave and the other's body diode conducts to ...
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SMPS: What is current mode instability (aka “sub-harmonic oscillation”)?
In peak current controlled switching power supplies, there is a phenomenon called “current mode instability” aka “sub-harmonic oscillation”. What is that? Can't seem to get a good explanation of this.....
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How to control power to a water heater
My water heater element is rated at 3.6kW at 240V. To use solar power efficiently, I would like to use excess solar power (in a grid-tied arrangement) to heat our domestic hot water. Our electricity ...
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What is reactive Power and how it is generated and what is its source?
Many people, including me are good with dealing with real and reactive power in power flow systems, but still has question at the end of the day: What is reactive power and how it is generated or what ...
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What to plug in first to usb charger when charging: wall outlet or cell phone and why? [closed]
I asked this question on Physics StackExchange but was advised to ask it here.
When I charge me cell phone or notebook or whatever device what should I plug in first? Should I at first plug in usb ...
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Equation 20.16 Proof
In studying the Fundamentals of power electronics by Robert Erickson I do not understand how they arrived at the equations for current and voltage
Link to Book, page 772 is where I am at
https://...
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How to limit current of an AC signal
For my project, I'm trying to work with the principle of electrovibration. This principle is about simulating textures using low current electricity on an insulated conductive surface (see Wikipedia).
...
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TRIAC keeps failing
IMPORTANT UPDATE (Update 6), scroll down to see.
I have been trying to make an AC (air conditioner) soft starter for my home AC unit.
I have built the following circuit and connected it to my AC unit ...
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How Long Will This Battery Keep My Fridge Powered For?
I have an interesting mathematical/electrical dilemma and I'm not sure where to start.
I am considering buying this fridge (specs on page).
I will be hopefully buying a battery pack with it to ...
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Nichrome wire connection with Arduino
I want to make a nichrome wire red-hot on command. I planned to use an Arduino along with it. The basic idea was to use an optocoupler to isolate the nichrome wire section from the microcontroller ...
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High power pulse generator
I'm designing a relatively high power pulse generator.
Basically I have a microcontroller generating a clean square wave (0-3.3 V or 0-5 V) which then goes into my amplification circuitry. I want to ...
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Capacitor voltage in buck converter and how it steps down voltage
I am having an issue understanding how the a buck converter circuit actually steps down the input voltage. Specifically, my issue is regarding the capacitor charging and discharging. Let's consider ...
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How can I make my flyback converter discharge immediately?
I'm using a flyback converter (220-100V to 19vdc) to power an electronics unit. But it doesn't discharge fast enough, this causes some relays to stay energised for a second or two after power supply ...
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Triac Switch Circuit using MOC3021 and BT136
I am tinkering with BT136 & MOC3021 optocoupler to control AC loads, and below is the schematic i have put together. I have a few doubts here.
Is the value of 100 ohm 1 watt correct on pin 6 of ...
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How to create a negative voltage supply? [closed]
I am trying to incorporate a LEM LAH 100-P current sensor into a project. It requires a dual polarity voltage supply between +/- 12 and 15 volts. What is the best way to implement it?
Digi-key has ...
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Stepping Up power (from 0.02-0.6 DC V input to 5-12 DC V output)
I want do design DC-DC converter to have a power supply that can charge an electronic device.
The issue behind in that the expected input range is 0.04-0.6 V DC. I chose both MT3608 and LTC3108.
My ...
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Where does the negative inductor current go during CCM at no load in synchronous converters?
As you all know, there are two primary mode of operation for dc-dc converters : CCM and DCM. At no load, the inductor current stops at zero at DCM. However, if CCM is enforced (such as Forced PWM), ...
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IR2110 max duty cycle
I'm using the high side of an IR2110 driver. If I set the duty cycle to 100% the circuit burns out, I haven't how can I calculate the max duty cycle for the driver in a given circuit?
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TRIAC Firing angle vs power delivered to load, how calculate?
I'm building a phase control system for simple power control to a given load (heater for example.)
I need an equation to find the relationship between angle of TRIAC firing vs power delivered to load (...
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How to use the same antenna to receive and transmit on the same frequency with an SDR [Half-Duplex]?
Considering that the SDR board has one TX/RX output/input and one RX input, I am wondering how could I use one antenna for a half duplex communications on the same frequency.
The idea is to use the ...
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Dynamic Braking MOSFET Control Circuit [duplicate]
I am dealing with a regenerative power situation with BLDC motor and servo drive controller.The power supply is 48V regulated DC but during deceleration due to regeneration, the voltage at drive ...
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Different type of capacitors
How can I distinguish between filter capacitors, decoupling capacitors, and bypass capacitors? What is the most basic and important difference in their functionality?
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How can I calculate the dead time to prevent shoot-through?
From Figure 1 is evident that to get the dead time I must define the values for RC. E.g my resistor is 220 ohms and capacitor is 0.1uF this gives me 22us at 1-time constant, however, when I measure ...
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can you explain me the working of this circuit in detail? [closed]
this circuit is a occupancy light circuit i want to know the working of the transistor regarding base,collector and emitter in the transitor
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Hacking DSLR battery to power camera from power supply [closed]
I would like to power my DSLR for long captures with a power supply. I know the voltage and inner structure of the official batteries. The battery has 2x 3,7V cells inside with a circuit. People ...
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How to select an LDO voltage regulator?
I have some doubts about how to select a voltage regulator. I am planning to use a Texas Instruments TPS7A05 LDO regulator to regulate my 5V (250 mA) to 3.3V (200mA) to power my STM32 microcontroller....
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How does EVSE gets the SoC of a vehicle in Level 1 and Level 2 chargers, Type2 Gun(IEC62196-2)?
Type2 gun does not allow full-fledged communication between the EV and EVSE, Electric vehicle can only tell the EVSE what state it is in through the control pilot. is it possible for EVSE to share SoC ...
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