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3 Two series motors are coupled One motor runs as generator and other as motor The friction losses of the two machines will be equal when?
Wiki User
∙ 11y ago
when both runs at same speed
Wiki User
∙ 11y ago
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Are the friction losses of the machine linear in induction motor electrical machines?
yes
What are the possible losses for a dc generator?
Friction in the bearings and in the commutator, and windage loss. Electrical resistance of the armature and field windings and the brushes.
What are the constant losses in a DC machine?
Constant losses Those losses in a d.c. generator which remain constant at all loads are known as constant losses. The constant losses in a d.c. generator are: (a) iron losses (b) mechanical losses (c) shunt field losses
Can a motor drive a generator which can produce power more than the power used by the motor to drive the generator?
Claims about perpetual motion machines are always false because they ignore the inevitable losses of energy which must be overcome to make any machine operate so that it can do its intended work. Such losses mean that any machine, whether electrical or mechanical, must be supplied with more input power than it can convert into output power. In the case of electrical machines there are many reasons for energy losses: Bearing friction losses; "windage" losses caused by air having to be moved out of the way by spinning parts such as rotating armatures and cooling fans; magnetic hysteresis losses absorbed by eddy currents flowing in rotor armature and stator laminations; commutation losses in dc machines and slip ring losses in ac machines; excitation losses caused by the need to supply energy to the coils in the stator of a machine in order to magnetize it; general electrical resistance losses caused by the need to use energy to force electric currents to flow through the windings of any electrical machine. Whilst engineers have found ways to reduce each one of those types of loss to a minimum, it is still a fact of life that no electrical machine can be 100% efficient. In the case of a motor, it will always require more energy to be supplied to it than it can convert to mechanical power. In the case of a generator, it will always require more mechanical power to be supplied to it than it can generate as electricity. Some electrical machines have a power-conversion efficiency of up to 80% but most have efficiencies much less than that. If a motor and a generator were linked together to form a motor-generator set (the motor driving the generator driving the same motor) then, if both machines were as good as 80% efficient, that would mean the combined efficiency of the system of would only be .8 x .8 = .64 i.e. 64%. In other words, to keep the motor-generator set running, additional power equal to at least 36% of the motor-generator set system's own power would need to be supplied from an external source. Those facts make the set-up described in the answer to this question shown below pure nonsense. Period.
Can you use a dc generator as a dc motor?
Yes you can turn a motor into a generator, if it is a permanent magnet motor.
Are the friction losses of the machine linear in induction motor electrical machines?
yes
What are the different kinds of losses in machines?
stray losses,armature copper losses,iron losses(Hysteresis and eddy current losses),mechanical losses(friction and windage losses)
What are the possible losses for a dc generator?
Friction in the bearings and in the commutator, and windage loss. Electrical resistance of the armature and field windings and the brushes.
The disadvantages of friction?
Losses due to friction mean that in a closed system there is never 100% transfer of energy and therefore no such thing as Perpetual Motion machines (although some get close).
How input work and output work computed on each type of simple machines?
(Output work) + (friction losses) = (input work) on any type of machine.
What are the constant losses in a DC machine?
Constant losses Those losses in a d.c. generator which remain constant at all loads are known as constant losses. The constant losses in a d.c. generator are: (a) iron losses (b) mechanical losses (c) shunt field losses
Can a motor drive a generator which can produce power more than the power used by the motor to drive the generator?
Claims about perpetual motion machines are always false because they ignore the inevitable losses of energy which must be overcome to make any machine operate so that it can do its intended work. Such losses mean that any machine, whether electrical or mechanical, must be supplied with more input power than it can convert into output power. In the case of electrical machines there are many reasons for energy losses: Bearing friction losses; "windage" losses caused by air having to be moved out of the way by spinning parts such as rotating armatures and cooling fans; magnetic hysteresis losses absorbed by eddy currents flowing in rotor armature and stator laminations; commutation losses in dc machines and slip ring losses in ac machines; excitation losses caused by the need to supply energy to the coils in the stator of a machine in order to magnetize it; general electrical resistance losses caused by the need to use energy to force electric currents to flow through the windings of any electrical machine. Whilst engineers have found ways to reduce each one of those types of loss to a minimum, it is still a fact of life that no electrical machine can be 100% efficient. In the case of a motor, it will always require more energy to be supplied to it than it can convert to mechanical power. In the case of a generator, it will always require more mechanical power to be supplied to it than it can generate as electricity. Some electrical machines have a power-conversion efficiency of up to 80% but most have efficiencies much less than that. If a motor and a generator were linked together to form a motor-generator set (the motor driving the generator driving the same motor) then, if both machines were as good as 80% efficient, that would mean the combined efficiency of the system of would only be .8 x .8 = .64 i.e. 64%. In other words, to keep the motor-generator set running, additional power equal to at least 36% of the motor-generator set system's own power would need to be supplied from an external source. Those facts make the set-up described in the answer to this question shown below pure nonsense. Period.
Can you use a dc generator as a dc motor?
Yes you can turn a motor into a generator, if it is a permanent magnet motor.
Does transformer has high or low efficiency?
Since, transfformer is a Static device (ie. no moving parts in it) hence it is the most efficient machines ever made by man. However, in rotating machines there are various losses like friction and windage, losses in commutator etc. So, yes, Transformers are highly efficient devices.
Which loss is not common between a transformer and rotating machines?
Frictional , rotating losses are not common to transformers and rotating machines. these are specific to rotating machines.
What are the losses have an induction machines?
A three phase induction machine have the Following losses:- 1. Stator core loss 2.Stator Ohmic loss 3.Rotor core loss 4.Rotor ohmic loss 5.Friction losses 6.windage losses 7.Stray losses 8.Also it'll depends upon the types of motor as if it is a slip ring type IM then it will have sparking losses at slip contact etc etc which are very small in comparison to above losses. Regards,,
How do we calculate Power generator losses?
I also have the same question. After some research, I understand that you cant just jump in and calculate this. You have to have alot of information about that spesific generator. I have found out that you can use some formulas from losses in transfomers.
