Two-reaction theory

⇉USED OF TWO REACTION THEORY This theory is used to resolve the given armature mmf in to two mutually prependicular components ,one component along the axis of rotor is known as direct axix(d-axix) components,and other prependicular to the axis of the rotor is known as quadrature axis(q-axis).The d-axis component of armature mmf Ｆa is denoted by Ｆd and the q-axis component by Ｆq. Ｆd=Ｆa sinψ Ｆq=Ｆa cosψ where ψ is the angle between the armature current  Ia and the excitation voltage Ef, and Fa is the amplitude of armature mmf. Magnetic axis of the rotor The axis of symmetryof the north magnetic  poles of  the rotor is called the direct axis(d-axis).The axis of symmetry halfway between adjacent north and south poles is called the quadrture axis(q-axis). Related links- Related links- Slip-test Basic concept of transformer Construction of three-phase synchronous machine