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In a DC machine, z, p, Ia and a are respectively the number of conductors, number of poles, armature current and number of parallel paths. The peak value of fundamental component of armature MMF wave is ____________ b) 8/Π2 c) 4/Π d) 8/Π2

In a DC machine, z, p, Ia and a are respectively the number of conductors, number of poles, armature current and number of parallel paths. The peak value of fundamental component of armature MMF wave is ____________ b) 8/Π2 c) 4/Π d) 8/Π2 Correct Answer (z/2p)(Ia/a)

The peak value of the fundamental sine component Fa for a DC machine is Fa=8/Π2 AT/pole.

Related Questions

Lightening conductors are used to protect building from lightning strikes. Which of the following statements is/are true about lightening conductors? 1) Lightening conductors create an electric field at its top that lightning strikes it preferentially 2) Lightning conductors reduce the effect of the strike by uniformly distributing the charge (current) over the surface of the building 3) Lightning conductors take all the charge (current) to deep down in the earth 4) Lightning conductors must be installed at a place taller than the building Select the correct answer using the code given below
The number of compensating conductors/pole faces is _______ (where Z is the number of active armature conductors/pole; A is number of parallel paths; Ia is the armature current).
Consider the following statements with respect to synchronous machines. State whether these statements are true or false. (a) Armature reaction is demagnetising when a generating machine supplies zero power factor lagging current. (b) Armature reaction is magnetising when a generating machine supplies zero power factor leading current. (c) Armature reaction is mostly cross-magnetising, though it has a small demagnetising component, when a generating machine supplies unity power factor current.
A 100KW, 250 V, 400 A, a long shunt compound generator has an armature resistance of 0.025 ohms. There are 1000 shunt fields turns per pole and 3 series field turns per pole. The series field is connected in a such a fashion that positive armature current produces direct-axis MMF which adds to that of the shunt field. Compute the gross MMF at the rated terminal current when shunt field current is 4.7A and speed is 1150 rpm.
Consider the following statements: In the above figure, the curves pertain to the DC motor A. Speed vs Armature current characteristic of a DC shunt motor B. Torque vs Armature current characteristic of a DC shunt motor C. Speed vs Armature current characteristic of a DC series motor D. Torque vs Armature current characteristic of a DC series motor
If F1 is the constant amplitude of fundamental rotating MMF wave, the space harmonics of order 6K+1 (where K=1,2,3….), the harmonic MMF wave is of _____________
If F1 is the constant amplitude of fundamental rotating MMF wave, the for the space harmonics of order 6K-1 (where K=1,2,3….), the harmonic MMF wave is of _____________
Suppose we want to design a synchronous circuit that processes a string of 0’s and 1’s. Given a string, it produces another string by replacing the first 1 in any subsequence of consecutive 1’s by a 0. Consider the following example. Input sequence: 00100011000011100 Output sequence: 00000001000001100 A Mealy Machine is a state machine where both the next state and the output are functions of the present state and the current input. The above mentioned circuit can be designed as a two-state Mealy machine. The states in the Mealy machine can be represented using Boolean values 0 and 1. We denote the current state, the next state, the next incoming bit, and the output bit of the Mealy machine by the variables s, t, b and y respectively. Assume the initial state of the Mealy machine is 0. What are the Boolean expressions corresponding to t and y in terms of s and b ?
A 400-V, 1000-A, lap wound dc machine has 10 poles, 860 armature conductors. The number of conductors in the pole face to give full compensation if pole face covers 70% of pole span is?
Peak value of fundamental component of MMF produced by one N-turn coil carrying a current ‘i’ is ____________