Answer :
Power plant having maximum demand more than the installed rated capacity will have utilisation factor more than unity.
asked
Mar 20, 2018
by
anonymous
Answer :
For high value of diversity factor, a power station of given installed capacity will be in a position to supply more number of consumers.
asked
Mar 20, 2018
by
anonymous
Description : Define : i) Maximum Value ii) RMS Value of ac supply
Answer :
i) Maximum Value :- The maximum or peak value attained by an alternating quantity during positive or negative half cycle, is called maximum value or peak value. ii) RMS Value of ac ... as produced by the alternating current when flowing through the same resistance and for the same time.
asked
Aug 17, 2019
by
anonymous
Answer :
In a power plant if the maximum demand on the plant is equal to the plant capacity, then plant reserve capacity will be zero.
asked
Mar 20, 2018
by
anonymous
Answer :
Maximum demand on a power plant is the greatest of all "short time interval averaged" demand during a period.
asked
Mar 20, 2018
by
anonymous
Description : What is the value of capacitance required to improve power factor from 0.7 to 0.9. Given that: Real power = 50 W Vrms of the source = 120 Frequency = 50 Hz #powerfactor
asked
May 17, 2020
by
anonymous
Answer :
An induction motor has relatively high power factor at near full load.
asked
Mar 20, 2018
by
anonymous
Answer :
In a distribution system, in order to improve power factor, the synchronous capacitors are installed at the receiving end.
asked
Mar 20, 2018
by
anonymous
Answer :
For a consumer the most economical power factor is generally 0.95 lagging .
asked
Mar 20, 2018
by
anonymous
Answer :
The primary reason for low power factor is supply system is due to installation of induction motors.
asked
Mar 20, 2018
by
anonymous
Answer :
Load factor of a power station is generally less than unity.
asked
Mar 20, 2018
by
anonymous
Answer :
Load factor of a power station is defined as average load/maximum demand.
asked
Mar 20, 2018
by
anonymous
Description : Can a synchronous condenser improve power factor?
Answer :
Yes, synchronous condenser can improve power factor.
asked
Mar 19, 2018
by
anonymous
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
Answer :
Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is 122.8 GWh
asked
Apr 29, 2018
by
anonymous
Description : What is the value of Beta in power BJT?
Answer :
The beta value in power BJT is 5 to 10.
asked
Sep 20, 2017
by
anonymous
Description : Maximum Power Transfer Theorem 1
Answer :
Maximum Power Transfer Theorem 1
asked
May 22, 2019
by
anonymous
Description : State maximum power transfer theorem for DC circuit.
Answer :
Maximum power transfer theorem for DC circuit: The maximum power transfer theorem states that the source or a network transfers maximum power to load only when the load resistance is equal ... removed (disconnected) ii) All internal independent sources are replaced by their internal resistances.
asked
Sep 6, 2018
by
anonymous
Description : An independent voltage source in series with an impedance ZS=R+jXS delivers a maximum average power to a load impedance ZL when A) ZL = R B) ZL = jXS C) ZL = R-jXS D) ZL = R+jXS
Answer :
An independent voltage source in series with an impedance ZS=R+jXS delivers a maximum average power to a load impedance ZL when ZL = R-jXS
asked
Jun 18, 2018
by
anonymous
Description : A certain power MOSFET has a maximum junction temperature specification of 1500o C, a junction-to-case thermal resistance of 1.00 C/W, and a junction-to ambient thermal resistance of 600 C/W. If the ambient temperature is 300o C, then the maximum allowable power dissipation in the device will be A) 1.52 W B) 1.72 W C) 1.92W D) 2.00 W
Answer :
A certain power MOSFET has a maximum junction temperature specification of 1500o C, a junction-to-case thermal resistance of 1.00 C/W, and a junction-to ambient thermal resistance of ... 300o C, then the maximum allowable power dissipation in the device will be 2.00 W
asked
Jun 18, 2018
by
anonymous
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
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
asked
Apr 28, 2018
by
anonymous
Description : For maximum transfer of power, internal resistance of the source should be?
Answer :
For maximum transfer of power, internal resistance of the source should be equal to load resistance.
asked
Mar 25, 2018
by
anonymous
Description : "Maximum power output is obtained from a network when the load resistance is equal to the output resistance of the network as seen from the terminals of the load". The above statement is associated with?
Answer :
"Maximum power output is obtained from a network when the load resistance is equal to the output resistance of the network as seen from the terminals of the load". The above statement is associated with Maximum power transfer theorem.
asked
Mar 25, 2018
by
anonymous
asked
Mar 20, 2018
by
anonymous
Answer :
The mechanical power developed by a shunt motor will be maximum when the ratio of back e.m.f. to applied voltage is 0.5.
asked
Mar 20, 2018
by
anonymous
Answer :
In a D.C. shunt motor, under the conditions of maximum power, the current in the armature will be more than full-load current.
asked
Mar 20, 2018
by
anonymous
Description : The maximum load that a power transformer can carry is limited by its?
Answer :
The maximum load that a power transformer can carry is limited by its voltage ratio.
asked
Mar 19, 2018
by
anonymous
Description : The synchronous motor will develop maximum power when the load angle is?
Answer :
The synchronous motor will develop maximum power when the load angle is 900.
asked
Mar 18, 2018
by
anonymous
Answer :
The value of starting capacitor of a fractional horse power motor will be 300 uF .
asked
Mar 20, 2018
by
anonymous
Description : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these
Answer :
What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these
asked
Apr 29, 2018
by
anonymous
Description : What is the power factor of purely resistive circuit.
Answer :
Unity that is 1
asked
Mar 16, 2018
by
anonymous
Description : What is the use of power factor correction?
asked
Mar 10, 2018
by
anonymous
Description : What is the best power factor?
Answer :
It is unity power factor but difficult to achieve in dynamic loads
asked
Mar 10, 2018
by
anonymous
Description : What is power factor angle?
asked
Mar 10, 2018
by
anonymous
Description : What is the advantage of high power factor?
Answer :
Reduced copper losses Smaller conductor size Improve voltage regulation Increase system capability Less energy bill
asked
Mar 10, 2018
by
anonymous
Description : State the effects of low power factor on efficiency and voltage regulation of short transmission lines.
Answer :
i) Effect of Low power factor on efficiency:- When power factor of load reduces current drawn by transmission line increases so copper losses in transmission line increases, hence transmission ... increases, so voltage drop in transmission line increases so regulation increases. (Become Poor)
asked
May 22, 2020
by
anonymous
Description : Briefly explain how the power factor of an inductive circuit can be improved.
Answer :
As we know that power factor should be corrected to ensure that the current supplied is cost friendly. Meaning the power factor should be around one but not greater than one(0.8-0.9) in a ... an inductive circuit due to the inductive reactance which oppose the change of current in the ac circuit.
asked
May 17, 2020
by
anonymous
Description : Why capacitors are used to improve power factor?
Answer :
Capacitors generate reactive power instead of that drawn from source which is required by inductive loads.so it reduce the reactive current which is drawn from source to be drawn from capacitor.This control in Electric bills cost.
asked
Aug 18, 2019
by
anonymous
Description : Discuss how power factor tariff results into energy conservation.
Answer :
Power factor tariff results into energy conservation: i) Applying incentives and penalties according to power factor is an effective way, which enables consumer to improve power factor so that he can ... finally leads to reduction in the current drawn by the load and helps for energy conservation.
asked
Sep 29, 2018
by
anonymous
Description : Draw and explain bulk correction method for power factor & control.
Answer :
Bulk correction method for power factor & control: i) Here individual starter controls the capacitors located at distribution panel. ii) Centralized compensation is employed in large industrial plants where many ... capacitor units in steps to maintain P.F. more than preset limit (0.95).
asked
Sep 29, 2018
by
anonymous
Description : State the incentives and penalties related with power factor tariff.
Answer :
Incentives and penalties related with power factor tariff: In addition to basic tariff (Maximum Demand Tariff / KVA Maximum Demand Tariff / Load factor tariff) the tariff in which P.F. of ... industrial consumer/H.T/ commercial consumers with contract demand above 80 kw/ 100Kva/107 hp consumer.
asked
Sep 22, 2018
by
anonymous
Description : With a neat sketch explain working of 1 phase dynamometer type power factor meter.
Answer :
Working of 1 phase dynamometer type power factor meter : The current coil is connected in series with load. Two pressure coils marked as A and B are connected across the supply terminals ... becomes stationary and the pointer shows steady deflection corresponding to the power factor of the load.
asked
Sep 6, 2018
by
anonymous
Description : State the significance of power factor.
Answer :
Significance of power factor:- 1. Cosine of angle between voltage & current in a circuit is called power factor. 2. It is a measure of the real power in a circuit. 3. Inductive & ... KVA rating equipment 5. Greater conductor size 6. CosØ = R/Z CosØ= Active Power/ Apparent Power
asked
Sep 6, 2018
by
anonymous
Description : A transformer has negative voltage regulation when its load power factor is (1) Zero (2) Unity (3) Leading (4) Lagging
Answer :
Leading
asked
Apr 30, 2018
by
anonymous
Description : The power factor of dielectric : (A) is a function of temperature of the dielectric only (B) depends only on voltage stress to which the dielectric is stressed (C) always constant (D) both (A) and (B)
Answer :
The power factor of dielectric : (A) is a function of temperature of the dielectric only (B) depends only on voltage stress to which the dielectric is stressed (C) always constant (D) both (A) and (B)
asked
Apr 30, 2018
by
anonymous
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) excitation emf leads the terminal voltage by the power factor angle (4) excitation emf lags the terminal voltage by the power factor angle
Answer :
In a synchronous generator delivering lagging power factor load the excitation emf leads terminal voltage by the power angle
asked
Apr 29, 2018
by
anonymous
Description : The benefit of power factor correction in a power system is (A) lower power consumption (B) increased demand charge (C) reduced load carrying capabilities in existing lines (D) reduced voltage profile
Answer :
The benefit of power factor correction in a power system is lower power consumption
asked
Apr 28, 2018
by
anonymous
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, 0.866 pu (B) 0.866 pu, 0.5 pu (C) 0.707 pu, 0.707 pu (D) 0.5 pu, 0.5 pu
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
asked
Apr 28, 2018
by
anonymous
Description : The power factor of a D.C. circuit is always?
Answer :
The power factor of a D.C. circuit is always unity.
asked
Mar 25, 2018
by
anonymous
Description : The ratio of active power to apparent power is known as____ factor.
Answer :
The ratio of active power to apparent power is known as power factor.
asked
Mar 25, 2018
by
anonymous
Description : The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is?
Answer :
The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is 32 kW.
asked
Mar 25, 2018
by
anonymous