If the load of the normally excited synchronous motor is increased the power factor will?

1 Answer

Answer :

If the load of the normally excited synchronous motor is increased the power factor will become lagging.

Related questions

Description : If the field of synchronous motor is under excited, power factor will be?

Last Answer : If the field of synchronous motor is under excited, power factor will be lagging.

Description : The synchronous motor which works on leading power factor and does not drive any mechanical load is called?

Last Answer : The synchronous motor which works on leading power factor and does not drive any mechanical load is called synchronous condenser.

Description : The synchronous motor will develop maximum power when the load angle is?

Last Answer : The synchronous motor will develop maximum power when the load angle is 900.

Description : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because?

Last Answer : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because stator supply is not required to produce magnetic field.

Description : In a synchronous generator delivering lagging power factor load  (1) the excitation emf leads terminal voltage by the power angle (2) the excitation emf lags terminal voltage by the power angle (3) ... by the power factor angle (4) excitation emf lags the terminal voltage by the power factor angle

Last Answer : In a synchronous generator delivering lagging power factor load the excitation emf leads terminal voltage by the power angle

Last Answer : Yes, we can make the power factor of synchronous motor leading by adjusting its excitation.

Last Answer : An over excited synchronous motor on noload is known as synchronous condenser.

Last Answer : A synchronous motor running with normal excitation adjusts to load increases essentially by increase in armature current.

Description : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as?

Last Answer : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as pull-in torque.

Last Answer : The coupling angle or load angle of synchronous motor is defined as the angle between the rotor and the stator poles of opposite polarity.

Last Answer : If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then the stator current will be zero.

Description : In a synchronous motor which losses varies with load?

Last Answer : In a synchronous motor, copper losses varies with load.

Last Answer : The standard full-load power factor ratings for synchronous motors are unity or 0.8 leading.

Last Answer : As the load is increased the speed of D.C. shunt motor will reduce slightly.

Last Answer : For power factor correction, synchronous motors operate at no-load and greatly over-excited fields.

Description : If we change the excitation of synchronous machine will it affect on power factor?

Last Answer : Yes, If we change the excitation of synchronous machine it will affect on power factor. If the synchronous motor is overexcited then it will have leading power factor and if the motor is underexcited then it will have lagging power factor.

Description : Why synchronous machine is called doubly excited machine?

Last Answer : Armature windings of synchronous machines either deliver 3 phase AC or absorb 3 phase AC source,  whereas field windings are energized from DC source. Thus due to presence of AC on armature and DC on field windings, synchronous machines are often referred as doubly excited machines.

Description : The effect of increasing load on a synchronous motor running with normal excitation is (A) Increase both its Ia and power factor. (B) Decrease Ia, but increase power factor. (C) Increase Ia, but decrease power factor (D) Decrease both Ia and power factor.

Last Answer : The effect of increasing load on a synchronous motor running with normal excitation is Increase Ia, but decrease power factor

Description : In synchronous motor, does the winding losses vary with load?

Last Answer : No, in the synchronous motor the winding losses do not vary with load.

Description : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are (A) 0.5 pu ... pu, 0.5 pu (C) 0.707 pu, 0.707 pu (D) 0.5 pu, 0.5 pu

Last Answer : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are 0.866 pu, 0.5 pu

Last Answer : In a distribution system, in order to improve power factor, the synchronous capacitors are installed at the receiving end.

Description : Can a synchronous condenser improve power factor?

Last Answer : Yes, synchronous condenser can improve power factor.

Description : A transformer has negative voltage regulation when its load power factor is   (1) Zero (2) Unity (3) Leading (4) Lagging

Last Answer : 0

Description : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is  (1) 122.8 GWh (2) 198.55 GWh (3) 128.2 GWh (4) 188.82 GWh

Last Answer : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is 122.8 GWh

Last Answer : The power factor of a single phase load can be calculated if the instruments available are three ammeters or three voltmeters.

Last Answer : Load factor of a power station is generally less than unity.

Last Answer : Load factor of a power station is defined as average load/maximum demand.

Description : Minimum voltage regulation occurs when the power factor of the load is?

Last Answer : Minimum voltage regulation occurs when the power factor of the load is leading.

Description : The maximum reluctance power of a salient-pole synchronous motor having direct-axis reactance, 1.0 pu and quadrature-axis reactance, 0.5 pu, and input voltage, 1.0 pu is (A) 0.25 pu (B) 0.5 pu (C) 1.0 pu (D) 1.5 pu

Last Answer : The maximum reluctance power of a salient-pole synchronous motor having direct-axis reactance, 1.0 pu and quadrature-axis reactance, 0.5 pu, and input voltage, 1.0 pu is 0.5 pu

Description : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ (A) directly proportional to α and Φ (B) ... proportional to α and inversely proportional to Φ (D) directly proportional to Φ and inversely proportional to α

Last Answer : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ directly proportional to α and inversely proportional to Φ

Last Answer : The increased load during summer months is due to increased use of fans and air conditioners.

Last Answer : When a D.C. series motor is connected to A.C. supply, the power factor will be low because of high inductance of field and armature circuits.

Last Answer : The power factor of a single-phase induction motor is usually lagging.

Last Answer : An induction motor has relatively high power factor at near full load.

Description : At which time power factor of the induction motor is low?

Last Answer : The power factor of the inducction motor is low at the time of starting as compare to while the induction motor is running.

Description : A separately excited dc motor operating in first quadrant is fed from 3-phase semi -converter free -wheeling diode is open circuited, then the motor :  (A) can be operated in first quadrant (B) ... in first & second quadrants (C) can be operated in first & fourth quadrants (D) cannot be operated

Last Answer : A separately excited dc motor operating in first quadrant is fed from 3-phase semi -converter free -wheeling diode is open circuited, then the motor : can be operated in first & fourth quadrants

Description : Separately Excited DC motor

Last Answer : Separately Excited DC motor

Last Answer : Slip-rings in a synchronous motor carry direct current.

Last Answer : The efficiency of a properly designed synchronous motor will usually fall in range 85 to 95%.

Last Answer : The operating speed of a synchronous motor can be changed to new fixed value by changing frequency.

Last Answer : A synchronous motor can develop synchronous torque at synchronous speed.

Last Answer : In case one phase of a three-phase synchronous motor is short-circuited the motor will not start.

Last Answer : In a synchronous motor, the armature current has large values for high and low excitation.

Last Answer :  The size of a synchronous motor decreases with the increase in flux density.

Last Answer : The duration of sudden short-circuit test on a synchronous motor is usually about one second.

Last Answer : The construction of a synchronous motor resembles an alternator.

Last Answer : If the field winding of an unloaded salient pole synchronous motor is open circuited, the motor will stop.

Last Answer : The armature current of the synchronous motor has large values for low and high excitation.

Description : Which motor have more efficiency, synchronous motor or induction motor?

Last Answer : Synchronous motor has more efficiency.

Description : If we change the excitation of synchronous machine will it affect on motor speed?

Last Answer : No, If we change the excitation of synchronous machine it will not affect on motor speed.