Hi,
I think your conclusion
Have a look at Bensen's spreadsheet and you will find that the peak current into a resistive load = peak current into a reactive load (when resistance does not change).
This is slightly misleading since total reactance probably measures the average current into the combined resistance + capacitance (or inductance).
If the combined reactance were adjusted to maintain the same current from the same driving voltage then the resistance reduces as the reactance increases.
Putting a lower resistance into Bensen will show the effect.
What does increase is the device dissipation when drivng reactive loads. At 45degree phase angle the device dissipation is up by a factor of three (with the same value of resistance) and at 60degree phase angle dissipation has gone up more than three times.
I think your conclusion
is incorrect.
Have a look at Bensen's spreadsheet and you will find that the peak current into a resistive load = peak current into a reactive load (when resistance does not change).
This is slightly misleading since total reactance probably measures the average current into the combined resistance + capacitance (or inductance).
If the combined reactance were adjusted to maintain the same current from the same driving voltage then the resistance reduces as the reactance increases.
Putting a lower resistance into Bensen will show the effect.
What does increase is the device dissipation when drivng reactive loads. At 45degree phase angle the device dissipation is up by a factor of three (with the same value of resistance) and at 60degree phase angle dissipation has gone up more than three times.
AndrewT
Yes a hasty comment from me, thanks for correcting me.
I agree that the current will not be higher in peak.
I did not say I said "higher peak" I said "higher" whitch is true if you look for an average value over time, whith I did not say
A pure ideal reactance "load" witch cannot disapate any energy just store and give back.
So a reactive load will put more stain on output stage as conducting time is longer whitch mean less marginal for SOA resting time and many amps have weak marginal for reactive loads.
I am interrested in transient behaviour with reactive loads can anyone shear som light on that?
(My math is rusty nowdays more than ten year has gone after any excercise, but I am interterested to gain some math knowledge back as it is very usful in this subject)
Yes a hasty comment from me, thanks for correcting me.
I agree that the current will not be higher in peak.
I did not say I said "higher peak" I said "higher" whitch is true if you look for an average value over time, whith I did not say
A pure ideal reactance "load" witch cannot disapate any energy just store and give back.
So a reactive load will put more stain on output stage as conducting time is longer whitch mean less marginal for SOA resting time and many amps have weak marginal for reactive loads.
I am interrested in transient behaviour with reactive loads can anyone shear som light on that?
(My math is rusty nowdays more than ten year has gone after any excercise, but I am interterested to gain some math knowledge back as it is very usful in this subject)
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