Frequency and duty cyle ?

[crazyjohn]

If i was switching a load on and off which uses less power 50 % duty at 10khz or 50 %at 1khz ?

How is power dissipation calculated when pwm is involved ?

 

[Syncopator]

If i was switching a load on and off which uses less power 50 % duty at 10khz or 50 %at 1khz ?

Both use the same amount of power.

How is power dissipation calculated when pwm is involved?

That depends on the pulse width/s. You would have to calculate the mean duty cycle.

 

[klystron]

Draw the time domain signal and integrate of at least 20 cycles to find the area under signal that is equal to the power

 

[crazyjohn]

Okay so if i find out that a device is on for 50ms and off for 50ms thats 10hz 50% duty i think and then calculated the power when it is on 100% duty by VxI to be 1 watt is the power dissipated simply 500mw and how does this change if the frequency is changed from 10hz to 100hz,1khz,10khz etc ?

 

[FvM]

find the area under signal that is equal to the power.

Strictly spoken, P = 1/T ∫VI dt respectively ∫V²/R dt in case of a resistive load.

Both use the same amount of power

If we can assume a pure resistive load and an ideal switch.

 

[jeevan.life]

In practice 10khz switching draws more power than the 1khz one...More switching..more leakage..more power

 

[biff44]

I was out for pizza yesterday. The owner says to me "you look hungry, I will cut it into 16 pieces for you". I replied "no, I could never eat 16 pieces...better cut it into only 8 pieces"

 

[InQuired]

From my point of view, it depends of the application. If you have an inductive load for instance, like a motor, the frequency will affect the response of your motor. The smaller is your motor, the higher your frequency will need to be to have the same response. You should provide us with your exact application for us to better help you.