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## What is meant by synchronising power?

Synchronizing Power is defined as the **varying of the synchronous power P on varying in the load angle δ**. It is also called stiffness of coupling, stability or rigidity factor. P s y n = V E f X s c o s δ P ∝ 1 X s. ∴ Synchronizing power of a synchronous machine is inversely proportional to the synchronous reactance.

## What is meant by synchronizing power coefficient?

The synchronizing power coefficient (𝑃syn) is **the measure of the stiffness of the electromagnetic coupling between the stator and the rotor**. A large value of the synchronizing coefficient (𝑃syn) shows that the electromagnetic coupling is rigid.

## What is meant by two reaction theory?

Two Reaction Theory was proposed by Andre Blondel. The theory **proposes to resolve the given armature MMFs into two mutually perpendicular components, with one located along the axis of the rotor of the salient pole**. It is known as the direct axis or d axis component.

## What is V and inverted V curves?

What is V Curve and inverted v curve? The **graphical representation of armature current Ia vs** field current If is called V-curve since the final view looks like English letter V. At the same time the power factor vs field current is called inverted V-curve of a synchronous motor.

## What is Q and D axis?

The axis along the axis of the rotor is called the direct or the d axis. The **axis perpendicular to the d axis is** known as the quadrature or q axis. The direct axis flux path involves two small air gaps and is the path of the minimum reluctance.

## What is the EMF equation of DC generator?

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.