Three Phase Bidirectional Delta Connected Controller:
Explain three phase half wave controller or three phase unidirectional controller.
Last Answer : Three phase half wave controller or unidirectional controller:
Explain three phase full wave controller.
Last Answer : Three phase full wave controller: Three phase full wave controller is also called as the three-phase bidirectional controller. Let the load is star connected so at each phase there are antiparallel connected SCRs. ... conduct at the same time and the third phase will be open.
A balanced Delta connected load supplied with 440 V 50 Hz three phase AC supply has R=10 Ohm and L=0.6 mH in is each arm. Calculate line and phase current, active power.
Draw the Delta connected three phase system showing all the voltages and currents. Write the power equation.
Explain the principle of ON-OFF control and phase control of AC voltage controller with suitable circuit and waveforms.
Last Answer : The integral cycle control (on-off control) and phase angle control are the two types of AC voltage controller. The principle of ON-OFF control: The on-off control is also called an integral cycle ... control. In phase control, the switch is on for some period of each cycle.
Explain three phase bridge inverter.
Last Answer : Three phase bridge inverter: Three phase bridge inverter converts DC voltage input to three-phase variable frequency variable voltage output. DC voltage source can be a DC source or output of the rectifier. ... in proper sequence. The switch may be thyristor or IGBT etc.
Consider a circuit with three parallel branches connected across a DC supply. What is the ratio of the branch currents I1 : I2 : I3 if the branch resistances are in the ratio of 2 : 3 : 4 respectively? A) 2 : 3 : 4 B) 6 : 4 : 3 C) 4 : 3 : 2 D) None of these
Last Answer : Consider a circuit with three parallel branches connected across a DC supply. What is the ratio of the branch currents I1 : I2 : I3 if the branch resistances are in the ratio of 2 : 3 : 4 respectively? A) 2 : 3 : 4 B) 6 : 4 : 3 C) 4 : 3 : 2 D) None of these
When three resistors with unequal values are connected in parallel, _______ A) The current across the resistors is the same B) The voltage drop across the resistors is the same C) The voltage drops across the resistors is proportional to the resistance of each resistor D) None of these
Last Answer : When three resistors with unequal values are connected in parallel, The voltage drop across the resistors is the same
three phase to single phase cycloconverter
Last Answer : three phase to single phase cycloconverter
In an R-C phase shift oscillator, the minimum no. of R-C networks to be connected in cascade will be -
Last Answer : In an R-C phase shift oscillator, the minimum no. of R-C networks to be connected in cascade will be 3
List different starting methods of three phase synchronous motor. Explain any one of them.
Last Answer : Different Starting Methods of Three Phase Synchronous Motor: As synchronous motor is not self starting, different methods of starting are as follows: 1) By using an Induction (Pony) motor 2) ... . The rotor gets pulled into synchronism and starts running at constant speed as a synchronous motor.
Explain with neat circuit diagrams the procedures to perform no load and blocked rotor tests on three phase induction motor.
Explain the need and steps to conduct the reduced voltage running up test on the three phase induction motor.
Explain power relations in three phase circuit.
What is line voltage and phase voltage? Draw balanced three phase star connected system. Show all the voltages and currents.
Is it possible for a soil to consist only of one phase?
What is the operation of three phase induction motor
THREE PHASE INDUCTION MOTORS MCQ
Last Answer : 101. Insertion of resistance in the stator of an induction motor (a) increases the load torque (b) decreases the starting torque (c) increases the starting torque (d) none of the above Ans: b
Why is a capacitor used in a single phase motor and not in three phase motor ?
Last Answer : In 1-phase induction motor capacitor work is generate the auxiliary winding current than excite the main winding to rotor starts rotate. After rotor start rotating about 75% of their speed than auxiliary ... emf to start the motor.so,in 3-phase induction motor is self start induction motor.
Why is a three phase denoted by R, Y, B ?
Last Answer : phase 1 ,R =Red colour cable terminal, phase 2 Y=Yellow colour terminal cable,Phase 3 B=Blue colour cable terminal, N =Neutral. For identification.
State any four advantages of three phase induction motor.
Last Answer : Advantages of three phase induction motor https://youtu.be/27OIOCKN05U
Define balanced and unbalanced load in three phase circuit.
Last Answer : Balanced Load: When all the imedances of 3 phases are equal in magnitude and of same nature then load is said to be balanced. Unbalanced Load: When all the imedances of 3 phases are not equal in magnitude and of different nature then load is said to be unbalanced.
State any four applications of three phase circuits.
Last Answer : The application of three phase circuits are 1. Three phase circuit is used for power transmission over long distances. 2. Three phase circuit can produce rotating magnetic field 3. Three phase ... three phase Motors and Transformers. 4. Three phase circuit is used for power converters circuits.
Draw the waveform of three phase AC supply voltage.
State advantages of three phase over single phase.
Last Answer : Advantages of 3-phase system over 1-phase system: - 1. More output: For the same size, output of poly-phase machines is always higher than single phase machines. 2. Smaller size: For ... are self- starting: The three phase ac motors are self starting, while single phase induction motor are not.
The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is
Last Answer : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is 4 percent
When a V-V three phase transformer system is converted into a Δ-Δ system, increase in capacity of the system is (A) 86.6% (B) 50% (C) 57.7% (D) 73.2%
Last Answer : When a V-V three phase transformer system is converted into a Δ-Δ system, increase in capacity of the system is 73.2%
In a three-phase supply floating neutral is undesirable because it way give rise to?
Last Answer : In a three-phase supply floating neutral is undesirable because it way give rise to unequal line voltages across the load.
Three phase synchronous motor will have how many sliprings?
Last Answer : Three phase synchronous motor will have two sliprings.
How is a three phase cage induction motor self starting?
Last Answer : Any type of induction motor is self starting. Because the reason for torqe production require two flux displaced by some angle theta.If theta is constant with time then torqe will be constant;if ... torqe also pulsating. In induction motor this angle theta is not pulsating.so it is self starting
What is mean by plugging in three phase induction motor?
Last Answer : Plugging in three-phase induction motor means interchanging of any two phases of a stator for quick stopping.
What is a three phase connection?
Last Answer : RYB, 440 volt/phase
how can we reverse the direction of rotation of three phase induction motor ?
Last Answer : The direction of rotation of three phase induction motor can be reversed by plugging i.e by changing any two out of three phases of the supply to the stator of the Induction motor terminal.
Write short notes on 3 phase AC system.
Temperature controller using SCR
Last Answer : Temperature controller using SCR The temperature control circuit is used to regulate the temperature. Figure shows the temperature control circuit using thermostat as temperature detector and SCR as ... half-cycle and heater gets connected to source to produce heat and raise the temperature.
A four -quadrant operation requires two full converters connected in (1) Series (3) Back to back (2) Parallel (4) Series Cascade
Last Answer : A four-quadrant operation requires two full converters connected in Parallel
Draw and explain pneumatic proportional controller.
Last Answer : Explanation : Basic : Proportional control is one in which the process input is change in direct proportion to the error(t) controls the output so that the manipulated variable and the error has proportional relation. ... the MV and SP reference value called as error Given as : Error = SP - MV
Explain Keypad controller.
Last Answer : Keypad Controller: It's a device which interfaces between the computer and keyboard. That is a input device and used for transfer the data to connected device.
What is the purpose of auxiliary controller in substation?
Last Answer : The systems of substation auxiliaries ensure operation of substations providing internal consumers of substations with operating direct and alternating currents. Any breakdown (loss) of auxiliary systems ... whole substation, as well as serious problems during its subsequent putting into operation.
Define Integral controller. State their advantages
Last Answer : Advantages of integral control action: 1) Improves steady state response 2) Removes offset error in the process variable. 3) Eliminates steady state error
When to select P-I controller? Give any two application of P-I controller.
Last Answer : Selection of P-I controller: The PI mode of controller is commonly selected for slow-to- moderate speed processes. Fast response of the system is not required. Large disturbances and ... an issue. As a adaptive controller for flow process. Real time pressure control process.
A Unified Power Flow Controller (FACTS controller) is a voltage source converter based (A) Inter-phase power controller (B) Static Compensator (C) Combination of series and shunt compensators (D) Solid-state series compensator
Last Answer : A Unified Power Flow Controller (FACTS controller) is a voltage source converter based Combination of series and shunt compensators
What is an electronic controller?
Explain the open delta (delta-delta) test on transformer.
Does Delta have something that I can plug my computer in to for power?
Last Answer : Older planes have to be retrofitted to have a power source by every seat. It is pretty standard on newer planes. Without knowing the the type of plane it would be impossible to know. And even with that it might be hard to say for certain. Your best bet is to call and ask.
Delta to Star Conversion Example
Last Answer : Delta to Star Conversion Example
Wye (Star) to Delta Conversion
Last Answer : Wye (Star) to Delta Conversion
Delta to Wye Conversion
Last Answer : Delta to Wye Conversion
Star to delta conversion examples
Last Answer : Star to delta conversion example 1
Wye and delta conversion formula
Last Answer : Wye and delta conversion formula