Questions tagged [efficiency]
A measure of the overall effectiveness of a system. For example, in power conversion, it would be the ratio of output power to input power.
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Does a processor consume more power to achieve the same performance when it's is hot than when it's cold?
I just had a random thought while observing the wattage of my laptop's CPU/GPU during a benchmark:
The processor's always being utilized at 100% during the benchmark. However, it was initially ...
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Energy consumption of a DC motor with or without reducer for a given workload
context
I'm electrifying a DH scooter for the the "uphill" part of the downhill fun. I obviously need a lot of torque in this regard. So I will likely use a reducer and/or chain drive ratio ...
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What prevents motors from creating mechanical energy with no energy loss?
I'm looking through dozens of direct-drive motors for a robotics project. I want to find the motor most efficient at converting electrical energy (to magnetic energy) to mechanical energy. The ...
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Confusion when Deriving Class A Amplifier Efficiency
I am currently taking an RF amplifier course at a university and I am having trouble understanding the derivation of efficiency for a class A amplifier. I understand the derivation pretty well for the ...
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Efficient rectifier for bike dynamo, LM74670
The question is relative to bike dynamo (actually an alternator) rectifying, the main goal being to minimize power loss. The system being mounted on a bicycle, space and weight are also a concern (so ...
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Regarding power consumption of electricity
I wonder - assuming I have a heater that consume x amount of electricity within 24 hour time frame. If I make a circuit that switch his power on and off every 5 minutes, will I consume 50% of ...
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Struggling with Buck Converter Efficiency at Light Loads
I’ve been testing a couple of Buck ICs using a power supply and an electronic load. While I can match the efficiency at higher loads, I’m facing issues at light loads (0.01A or lower). Specifically:
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Any additional advantage to keeping mosfets cool?
I know there is nothing to worry about if the operating temperature of a mosfet is under 100 degree C and manufacturers usually don't bother to install a heatsink if the mosfet is operating under this ...
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Does it ever make sense to build a shift register with DRAM cells?
Let's say you have a circuit with a shift register.
You know for a fact this shift register will get a clock signal every tick no matter what happens. There is no clock gate anywhere between the clock ...
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Boost Converter Efficiency Input Current
I'm trying to learn about DC-DC Boost converters and with the help of WEBENCH I've made this circuit:
Parameters are:
Vin: (4.95 - 5.05) V
Vout: 17 V
Iout: 300mA
Efficiency: 95.2%
My main questions ...
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Will the efficiency of PMSM motor increase if it is rewound for high voltage keeping everything else the same?
The background is:
I have to redesign a 10.8 volt DC-battery supply, PMSM 3-phase motor to work with 24VDC. I can only rewind the current motor and adjust it to 24VDC.
The motor is rated for 550 watts ...
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Theoretically, how low voltage can we go to reduce power consumption in CPUs?
My understanding is that power consumption of a CPU is approximately given by \$C\cdot V^2\cdot f\$ (capacitance, voltage, frequency).
Suppose we wanted to design a CPU so as to reduce CPU energy-...
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What Causes Hand- Wound and Machine-Wound Motors to Have Different kV? Expected Efficiency and Power Differences?
I am trying to understand the motor power and efficiency of two identical motors with the only difference being the winding technique (hand-wound and machine-wound).
Both are essentially the same hub ...
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Estimating an induction motor slip
i need to extract a fans' RPM using the AC current frequency. I don't have the means to actually measure RPM but i have some nameplate values for the motor.
given that i have the slip rating at full ...
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Darlington NPN preregulator for LDO step down 42v to 12v ~ transistors keep blowing up
this is a follow-up from the original post about this circuit which can be found here. the purpose of this circuit is to reduce the voltage to a lower level that is more palatable for the LDO. and it ...
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