Eph = Average value x form factor Equation (1) shown above is the EMF equation of the Synchronous Generator. The Coil Span Factor is defined as the ratio of the induced emf in a coil when the winding is short-pitched to the induced emf in the same coil when the winding is full pitched.

As the armature rotates, a voltage is generated in its coils. In the case of a generator, the emf of rotation is called the Generated emf or Armature emf and is denoted as Er = Eg. In the case of a motor, the emf of rotation is known as Back emf or Counter emf and represented as Er = Eb.

The synchronous speed of an AC motor is determined by the frequency of the source and the number of poles. The RPM is calculated by multiplying the frequency times 60 and dividing by the number of pairs of poles.

EMF equation of alternator

1. By faraday’s law of electromagnetic induction, the emf induced is proportional to rate of change of flux.
2. RMS value of emf per phase = Form factor x Average value of induced emf = 1.11 x 4 Φ f T.

The emf of a generator is sent to a light bulb with the system of rings and brushes shown. The graph gives the emf of the generator as a function of time. emf0 is the peak emf. The period is T = 1/f = 2π/ω, where f is the frequency.

If we know the resulting energy and the amount of charge passing through the cell. It is the simplest way to calculate the EMF. The electromotive force of cell….The Formula for Calculating the EMF.

The synchronous motor is used for converting the electrical energy into mechanical energy. The stator and the rotor are the two main parts of the synchronous motor. The armature winding is the main winding because of which the EMF induces in the motor. The rotator carry the field windings.

The RMS value of a sinusoidal AC voltage is 1.11 times its average value. Hence effective RMS value of EMF induced per phase can be found by multiplying Equation [3] by 1.11. Where, α is the slot angle and m is the number of slots per pole per phase.

If the machine DC Machine is working as a Motor, the induced emf is given by the equation shown below. In a motor, the induced emf is called Back Emf (Eb) because it acts opposite to the supply voltage.

EMF Equation of a DC Motor The basic DC motor’s E.M.F equation is given below. Eb = PΦNZ / 60A

In the case of a motor, the emf of rotation is known as Back emf or Counter emf and represented as Er = Eb. The expression for emf is same for both the operations, i.e., for Generator as well as for Motor. Derivation of EMF Equation of a DC Machine – Generator and Motor

In synchronous machines, EMF is induced due to the relative motion between the rotor flux and the stator conductors. In the case of transformers, EMF is induced in the winding due to the linkage of the time-varying flux with stationary coils.