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What else can I help you with?
Why does the open-circuit test essentially show only excitation losses and not in copper losses?
Oh, dude, the open-circuit test is like when you're checking out a car but not actually driving it - you're just seeing how it revs up without any load. So, it's all about measuring the excitation losses because there's no current flowing through the windings to cause copper losses. It's like checking out a car's engine without actually taking it for a spin - you're just seeing how it purrs without any real work.
Why the rotor of an alternator at rated power dissipates more heat at a low power factor load?
In an alternator, the load current is supplied by the stator and the excitation is applied to the rotor. When the power factor is low (lagging), more excitation is required to maintain rated output voltage at rated current. More excitation is also required to maintain rated output voltage with increased output current. Increased excitation current means increased rotor losses that must be dissipated as heat. (akash)
What components comprise the excitation current of a transformer?
A transformer's excitation current can be resolved into two components. The first is in phase with the primary voltage, and is responsible for the losses. The second lags the supply voltage by 90 degrees, and is responsible for magnetising the core.
What are the three main power losses that contribute to transistors junction temperature?
Switching losses Conduction losses
What is the condition for maximum efficiency of a DC machine?
The condition for maximum efficiency of a d.c. machine is that VARIABLE LOSSES must be equal to CONSTANT LOSSES i.e., variable losses = constant losses..
What are the different types of magnetic losses occurring in ferromagnetic materials under AC excitation?
types of magnetic losses
Why does the short-circuit test essentially show only i2R losses and not excitation losses in a transformer?
The short-circuit test on a transformer primarily assesses the copper losses, represented by i²R losses, because it is performed at a reduced voltage that allows full-load current to flow while keeping the output voltage low. In this condition, the magnetic circuit is already magnetized from prior tests, so the core does not require significant additional magnetizing current, thus minimizing excitation losses. Consequently, the test focuses on the resistive losses in the windings rather than losses due to hysteresis or eddy currents in the core.
What is the significant relationship of the no load loss in excitation current test in transformer?
The no load losses are the losses caused by energizing the transformer. These are constant losses, regardless of loading. This in effect tells you the efficiency of the transformer. (Power in) - (no load losses) = (Power out)
Why does the open-circuit test essentially show only excitation losses and not in copper losses?
Oh, dude, the open-circuit test is like when you're checking out a car but not actually driving it - you're just seeing how it revs up without any load. So, it's all about measuring the excitation losses because there's no current flowing through the windings to cause copper losses. It's like checking out a car's engine without actually taking it for a spin - you're just seeing how it purrs without any real work.
Why the rotor of an alternator at rated power dissipates more heat at a low power factor load?
In an alternator, the load current is supplied by the stator and the excitation is applied to the rotor. When the power factor is low (lagging), more excitation is required to maintain rated output voltage at rated current. More excitation is also required to maintain rated output voltage with increased output current. Increased excitation current means increased rotor losses that must be dissipated as heat. (akash)
What components comprise the excitation current of a transformer?
A transformer's excitation current can be resolved into two components. The first is in phase with the primary voltage, and is responsible for the losses. The second lags the supply voltage by 90 degrees, and is responsible for magnetising the core.
What are the reasons for for the decrease in terminal voltage of a seperately excited generator?
The decrease in terminal voltage of a separately excited generator can be attributed to several factors, including increased load demand, which causes a drop in output voltage due to the internal resistance of the generator. Additionally, losses such as copper losses (I²R losses) in the armature and excitation system, as well as core losses, can contribute to a reduction in voltage. Another factor could be a decrease in the excitation current, which reduces the magnetic field strength and subsequently lowers the generated voltage. Lastly, any faults or issues in the electrical connections or components can also lead to decreased terminal voltage.
Can a motor works as a dynamo I'mean produce electricity?
Yes, but if you are asking if that configuration can be sustained, i.e. as a perpetual motion machine, the answer is no. There will always be losses associated with power conversion, and these losses make a perpetual motion machine an impossibility.
What did means by the stray losses in induction motors or transformer or generator?
Stray losses refer to secondary voltage to be inappropriately distributed to transformers, induction motors and generators. Stray losses essentially mean that there is leakage that causes a weakening of the voltage being delivered to the motor.
What is windage loss of motor?
Windage loss is essentially frictional losses acting on rotating members due to air resistance.
What is iron loss?
Iron losses (Pi) are independent of of load which occur due to pulsation of flux in the core. Iron losses include both Hysteresis loss and eddy current loss and is same at all the loads.
What does turtle mean by the expression paper losses...doesn't mean anything?
In the context of investing, "paper losses" refer to losses on investments that have not yet been realized through a sale; essentially, they are hypothetical losses on paper rather than actual cash losses. When Turtle says "paper losses... doesn't mean anything," he suggests that such losses shouldn't be a cause for concern unless the investor decides to sell the asset. It emphasizes the idea that market fluctuations are normal, and the true measure of an investment's success is realized gains or losses, not unrealized ones.
