When the current drawn by synchronous motor would be minimum?

For constant power, the current drawn by a synchronous motor will be minimum when the power factor is: Leading. Lagging. Unity.

Why does a synchronous motor have a unity power factor?

Unity power factor synchronous motors are designed to operate in this way. A full load, with excitation they require no lagging reactive kVA from the line, nor do they supply leading reactive kVA to the line; they run at unity power factor with a minimum amount of stator current, and hence at highest efficiency [15].

Can you operate a synchronous motor with unity power factor?

Synchronous motors are designed to operate at unity (1.0) power factor or 0.8 leading power factor. By varying the DC excitation of the motor, the power factor of the motor can be varied widely. Overexcited synchronous motors operate at leading power factor and provide reactive kVAR-like capacitors.

What is the power factor of a synchronous motor at no load?

unity power factor
If the field current is increased, the pf will become. leading and the current will increase.

Why are synchronous motors more efficient?

The efficiency depends on the specific motor type and size, but the lack of slip in synchronous motors means there is less energy lost in converting between electrical energy and mechanical energy.

Why a synchronous motor is named so?

Definition: The motor which runs at synchronous speed is known as the synchronous motor. The synchronous speed is the constant speed at which the motor generates the electromotive force. The synchronous motor is used for converting the electrical energy into mechanical energy.

What is the minimum value of power factor?

The minimum value of power factor is zero. It occurs in a purely inductive circuit. The maximum value of power factor is one. It occurs in a pure resistor circuit.

Why do we use synchronous motors?

In higher power industrial sizes, the synchronous motor provides two important functions. First, it is a highly efficient means of converting AC energy to work. Second, it can operate at leading or unity power factor and thereby provide power-factor correction.

Why DC supply is used in synchronous motor?

When AC supply is given to the stator winding or static armature winding of the synchronous motor it creates a rotating magnetic field. If we give DC supply to the field winding or rotor winding of the synchronous motor then the pole created in the rotor will be constant.

Why synchronous motor is doubly excited?

A synchronous machine is called a doubly excited machine because both its rotor and stator are excited. The stator of 3 phase synchronous motor is excited with a 3-phase supply while rotor is with DC Supply.

What is the maximum and minimum of power factor?

The minimum value of power factor is zero. It occurs in a purely inductive circuit. The maximum value of power factor is one.